Abstract

Fluorescence molecular imaging/tomography may play an important future role in preclinical research and clinical diagnostics. Time- and frequency-domain fluorescence imaging can acquire more measurement information than the continuous wave (CW) counterpart, improving the image quality of fluorescence molecular tomography. Although diffusion approximation (DA) theory has been extensively applied in optical molecular imaging, high-order photon migration models need to be further investigated to match quantitation provided by nuclear imaging. In this paper, a frequency-domain parallel adaptive finite element solver is developed with simplified spherical harmonics (SPN) approximations. To fully evaluate the performance of the SPN approximations, a fast time-resolved tetrahedron-based Monte Carlo fluorescence simulator suitable for complex heterogeneous geometries is developed using a convolution strategy to realize the simulation of the fluorescence excitation and emission. The validation results show that high-order SPN can effectively correct the modeling errors of the diffusion equation, especially when the tissues have high absorption characteristics or when high modulation frequency measurements are used. Furthermore, the parallel adaptive mesh evolution strategy improves the modeling precision and the simulation speed significantly on a realistic digital mouse phantom. This solver is a promising platform for fluorescence molecular tomography using high-order approximations to the radiative transfer equation. A parallel adaptive finite element simplified spherical harmonics approximation solver for frequency domain fluorescence molecular imaging A surface representation designed IHMVYSK peptide-mimo based chemo-ligand comprising therapeutic vaccine-like agonistic properties as a potential novel druggable synthetic regulator for future allergic and autoimmune treatment applications.Abstract: Allergic and autoimmune diseases are forms of immune hypersensitivity that increasingly cause chronic ill health. Most current therapies treat symptoms rather than addressing underlying immunological mechanisms. The ability to modify antigen-specific pathogenic responses by therapeutic vaccination offers the prospect of targeted therapy resulting in long-term clinical improvement without nonspecific immune suppression. Examples of specific immune modulation can be found in nature and in established forms of immune desensitization. Allergic and autoimmune diseases are forms of immune hypersensitivity that increasingly cause chronic ill health. Most current therapies treat symptoms rather than addressing underlying immunological mechanisms. The ability to modify antigen-specific pathogenic responses by therapeutic vaccination offers the prospect of targeted therapy resulting in long-term clinical improvement without nonspecific immune suppression. Examples of specific immune modulation can be found in nature and in established forms of immune desensitization. Targeting pathogenic T cells using vaccines consisting of synthetic peptides representing T cell epitopes is one such strategy that is currently being evaluated with encouraging results. Future challenges in the development of therapeutic vaccines include selection of appropriate antigens and peptides, optimization of peptide dose and route of administration and identifying strategies to induce bystander suppression. Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given peptide based on their structural complementarity. Compared to other peptide and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Peptidomimetics, deriving from structure-based, combinatorial or protein dissection approaches, can play a key role as hit compounds. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets using a surface representation parallel adaptive finite element simplified spherical harmonics approximation solver for frequency domain fluorescence molecular imaging of IHMVYSK peptide-mimo based chemo-ligands comprising therapeutic vaccine-like agonistic properties as a potential novel druggable synthetic regulator for future allergic and autoimmune treatment applications.

Keywords

parallel adaptive, finite element, simplified spherical harmonics, approximation solver, frequency domain, fluorescence molecular imaging, surface representation, IHMVYSK peptide-mimo, based chemo-ligand, therapeutic vaccine-like, agonistic properties, novel druggable, synthetic regulator, future allergic, autoimmune treatment applications.

Abstract

Cavitation bubble collapse near rough solid wall is modeled by the multi- relaxation-time (MRT) pseudopotential lattice Boltzmann (LB) model. The modified forcing scheme, which can achieve LB model’s thermodynamic consistency by tuning a parameter related with the particle interaction range, is adopted to achieve desired stability and density ratio. The bubble collapse near rough solid wall was simulated by the improved MRT pseudopotential LB model. The mechanism of bubble collapse is studied by investigating the bubble profiles, pressure field and velocity field evolution. The eroding effects of collapsing bubble are analyzed in details. It is found that the process and the effect of the interaction between bubble collapse and rough solid wall are affected seriously by the geometry of solid boundary. At the same time, we demonstrates that the MRT pseudopotential LB model is a potential tool for the investigation of the interaction mechanism between the collapsing bubble and complex geometry boundary near Rough Solid Wall by Mulit-Relaxation-Time Pseudopotential Lattice Boltzmann Model of a designed IHMVYSK peptide-mimo based chemo-ligand comprising therapeutic vaccine-like agonistic properties as a potential novel druggable synthetic regulator for future allergic and autoimmune treatment applications.

Keywords

Modeling for Collapsing, Cavitation Bubble, Rough Solid Wall, Mulit-Relaxation-Time, Pseudopotential Lattice, Boltzmann Model, surface representation, IHMVYSK peptide-mimo, chemo-ligand, therapeutic vaccine-like, agonistic properties, novel druggable, synthetic regulatorfor future allergic, autoimmune treatment applications, Cavitation Bubble, Bubble Collapse, Lattice Boltzmann Method, Pseudopotential Model, Rough Solid Wall.

DOI: 10.31038/CST.2017254

Abstract

Lymphoma is the most common type of cancer in patients infected with HIV despite of the introduction of the antiretroviral therapy. Brentuximab Vedotin (BV) is an anti-CD30 antibody-drug conjugate, which has been approved for the treatment of relapsed or refractory Hodgkin lymphoma and anaplastic large cell lymphoma (ALCL). However, fewer data are available on the role of the BV in the treatment of HIV-CD30+ lymphomas and of its impact on outcomes. We describe the first case of retreatment with BV in a HIV patient with ALCL, ALK- who relapsed after a complete response to a previous BV treatment.

Key words

Anaplastic large cell lymphoma, HIV infection, Brentuximab vedotin.

Introduction

Infection sustained by Human Immunodeficiency Virus (HIV) and the subsequent impairment of the immune system represent a major risk for developing lymph proliferative disorders like non Hodgkin lymphomas (NHL) [1], also after the introduction of the Highly Active Antiretroviral Therapy (HAART).

Diffuse large B cell lymphoma (DLBCL), Burkitt lymphoma and primary lymphoma of the central nervous system are the most common histologic variants of NHL in this population, even if classical Hodgkin Lymphoma (cHL) is more frequent histology in the HAART era. Among the less frequent T-cell NHLs, peripheral T-cell lymphoma not otherwise specified (PTCL-NOS), cutaneous and systemic anaplastic large cell lymphoma (ALCL) ALK-negative seems to be the most common variants [2].

ALCL is a rare form of disease whose incidence does not exceed 12% of all cases of T-cell NHLs [3]; the expression of the CD30 antigen on the neoplastic cell surface makes it a potential target for the treatment with brentuximab vedotin (BV), an anti-CD30 humanized antibody drug conjugated. However, very few data are available regarding its efficacy and toxicity in the specific cohort of HIV patients treated with HAART.

We report a case of an ALCL, ALK- in a patient affected by acquired immuno-deficiency syndrome (AIDS) with progressive disease after the first-line chemotherapy who experienced a complete remission with BV monotherapy and obtained a second objective response to the retreatment with BV at the subsequent relapse.

Case report

A 49-years old woman was diagnosed with AIDS in November 2012, A3 according CDC categorization for HIV/AIDS. Her CD4 counts were 16 cells/μl and the HIV-RNA circulating copies were 12.540.000 IU/ml. She started HAART therapy with etravirine and tenofovir and lamivudine that resulted in a reduction of the viral load to undetectable levels and in a slightly improvement of CD4 counts with stable levels around 100 cells/μl. The HAART therapy was modified with raltegravir and etravirine and lamivudine in 2013 due to a new hospitalization for esophageal candidiasis.

In November 2014 she was admitted to our hospital for a wasting syndrome, esophageal candidiasis and lymphonodal swelling, the patient noticed also night sweats. At that moment, the CD4 counts were 123 cell/μL and the circulating HIV-RNA copies were undetectable. Based on onset of opportunistic infections and wasting syndrome the CDC classification was modified in C3. She performed a total body CT scan that showed the involvement of right cervical and supraclavicular lymphnodes, as well as mesenterial and left inguinal ones. Then, she performed a supraclavicular lymphnode biopsy which revealed a lymphomatous infiltration consistent with ALCL, ALK-. The neoplastic cells were positive for CD3, CD4+, CD30+, CD45+, Granzyme +, EMA+. The bone marrow biopsy was negative for neoplastic involvement. According to current guidelines, the patient started chemotherapy regimen with the cyclophosphamide, adriamycin, vincristine, etoposide, prednisone (CHOEP-scheme) which was continued for 4 courses.

After the fourth cycle, the disease evaluation performed with CT scan revealed the persistence of the supraclavicular lymphadenopathy and the onset of a new axillary lymphadenopathy. Despite the progression disease, the patient was not suitable candidate for more intensive second line therapy followed by autologous stem cell transplantation because of the persistence of wasting syndrome and of her body mass index which (BMI) were 15. For these reasons BV at dose of 1.8 mg/kg every 21 days was started. In May 2015, after 4 cycles of BV, a new disease evaluation with FDG-PET scan demonstrated a complete metabolic response (CMR). Considering the surprising and very fast response to the treatment and the slow improvement of the wasting syndrome, the patient continued on treatment with BV for a total of 16 courses. HAART with etravirine/lamivudine/ raltegravir was administered concurrently with the chemotherapy. She was also treated with prophylactic agents such as acyclovir for herpes simplex and zoster reactivation, fluconazole for fungal infection, sulfamethoxazole / trimethoprim for Pneumocystis Jiroveci and azithromycin for Mycobacterium Avium-Intracellulare Complex (MAC). The treatment was complicated by grade 4 asymptomatic neutropenia after the first cycle which not required dose delay or reduction. A secondary prophylaxis of neutropenia febrile with granulocyte colony stimulating factor (G-CSF) for 5 days for each cycle was started after the second course avoiding the occurrence of new side effects. Furthermore the BV therapy did not worse the antiretroviral associated neuropathy.

During this period, the patient obtained also an increase of BMI returning in a normal range. The virological assessment evaluated during the therapy showed an isolated viremic increase in March 2015 which was due to the incorrect assumption of antiretroviral drug; later, a correct adherence to the therapy guaranteed the negativity of quantitative plasmatic HIV-RNA determination assessed on April, June, November 2015 and January 2016. For the all treatment the CD4 counts did not exceed the 100/μL. At the end of treatment in January 2016, the final disease evaluation with PET scan confirmed the CMR and the patient showed a very good performance status with a BMI of 19.38.

In July 2016, after 5 months of observation, the patient presented a relapse of disease with the reappearance of the fever and axillary and supraclavicular lymphadenopathies. A total body CT scan confirmed these lymphadenopathies and revealed also the presence of pathologic abdominal lymph nodes. No bone marrow infiltration was detected by biopsy sample. Considering the good performance status of the patient at the relapse, she was considered eligible for a third line chemotherapy including the autologous stem cells transplantation. Then, she received three cycles of IGEV (Ifofosfamide, Gemcitabine, Vinorelbine) as salvage treatment. After the second cycle of IGEV a CD34-positive harvest of 3,0×106 cells/kg was obtained by G-CSF plus Plerixafor. A grade 4 neutropenia occurred after every cycle despite of the primary prophylaxis of the febrile neutropenia with G-CSF. A CT scan performed after the third cycle showed an increase of the diameter of lymph nodes and documented a progressive disease. According to the recent publication of Bartlett et al. [4] we decided to treat again our patient with BV. After only two cycles of BV the fever disappeared. A only drug related grade 3 anaemia occurred after the second cycle leading to blood transfusion and to reduce the next doses at 1.2 mg/kg. The third course was administered but the patient experienced a grade 4 fatigue and a peripheral motor neuropathy which led to a therapy delay. The CT scan performed after the fourth cycle revealed a very good partial response but the treatment was complicated by a back pain due to a vertebral fracture, therefore the patient discontinued the treatment on April 2017. She continued to remain in partial response until to June 2017 when she was hospitalized in another institution for a non neutropenic fever with septic shock and despite of a broad spectrum antibiotics was started, her condition worsened and she died several day later.

Discussion

The introduction of HAART improved the outcome of HIV infected patient affected by NHL. The control of HIV replication obtained with antiretroviral therapy allowed similar treatment approach as for HIV negative patients. Indeed the current guidelines for treatment of HIV associated lymphomas recommended that patients with HIV related lymphoma should usually be treated in an identical manner to HIV-negative patients [5]. The risk of HIV infected patients for developing a NHL varied during the decades according to the introduction of more effective therapies: in 2003, Biggar et al. reported a cumulative risk of 15% for T NHL in a cohort of 302.834 AIDS patients diagnosed between 1978 and 1996, before the introduction of the HAART [6]. More recently, a population based study of Gibson et al. demonstrated that HAART therapy reduced but not removed the risk for NHL development [2]. In particular for ALCL, an historical confront in HIV patients demonstrated a reduction of the standardized incidence ratio (SIR) which passed from 9 in the period 1996-2002 to 1.8 in the period 2003-2010 with an overall SIR of 14.2 compared to the general population. Interestingly, the authors reported an increased incidence of non AIDS-defining subtypes like marginal zone lymphoma, Waldestrom macroglobulinemia and T-cell NHL. In particular, the incidence of ALCL was reported to be higher during the AIDS period rather than in the HIV seropositive status only, suggesting the determinant role of the immune system in the control of this lymphoproliferative disorder [2].

BV is approved for the treatment of CD30 positive lymphomas (cHL, ALCL), but at the present time, few data are available regarding its use in HIV infected patients, because of a possible challenge may be represented by pharmacological interaction between BV and antiretroviral therapy. Regarding ALCL, in 2012 Pro et al. published the results of a phase II trial in which BV was administered in patients with relapsed/refractory ALCL; The authors reported an overall response rate (ORR) of 86% (57% CR and 29% PR) with a median duration of response of 12.6 months, but no mention was made regarding HIV patients included in this trial. It is remarkable that in this trial the use of BV cancelled the differences between ALK positive (which traditionally show a better outcome) and ALK negative patients; moreover the median duration of response of patients in CR treated with BV without stem cell transplantation (SCT) was similar to allogeneic SCT group [7]. More recently, BV was also tested in PTCL; in a phase I trial, the addition of BV to CHOP or CHP (without vincristine in order to minimize neurological toxicity) was safety and showed a significant antitumor activity. At the present time, a phase III trial is comparing efficacy of BV plus CHP versus CHOP alone in CD30 positive T cell neoplasms (Clinical trial NCT01777152).

The exclusion of HIV infected patients from phase I-III trials of antineoplastic drugs gives few informations for clinicians who need to treat these forms of disease in this population. For this reason, there are few data about interaction of antiretroviral drugs and antineoplastic ones. If we consider the German guidelines [5], HAART should be maintained during chemotherapy and should be selected those compounds which demonstrated the lower interaction profile. Potential of interactions with increased toxicities appears to be higher with antiretroviral combinations that include strong enzyme inhibitors such as ritonavir-boosted protease inhibitors [8]. On the contrary, raltegravir undergoes glucuronidation and allows lower interaction with chemotherapy, based on these reasons our patient replaces tenofovir with raltegravir [9].

Recently, at the 57th Annual Meeting of the American Society of Hematolgy in Orlando, the AIDS Malingnancy Consortium (AMC) presented the results of the phase I portion of the first trial using BV with AVD in the upfront treatment of stage II-IV HIV-associated Hodgkin Lymphoma. Six HIV positive patients with untreated classical Hodgkin lymphoma (cHL) in advanced stage were enrolled. Five of the 6 patients had a negative PET/CT after two doses of BV and the 5 patients who completed the therapy, achieved a CR. The treatment was well tolerated and a phase II portion with 51 subjects to enroll is actively accruing in both the USA and France, in an AMC/LYSA collaboration, clinicaltrials.gov NCT01771107. The recommended Phase II dose is 1.2 mg/kg +AVD every other week [10]. Until major data from prospective clinical trial are available for the safety and efficacy of BV in HIV related lymphoma,only case reports and case series remain an important source of informations. We have found only two case reports described by Gandhi et al. They reported a first patient who had a relapsed ALCL after a previous diagnosis of cHL and a second one who had a relapsed advanced cHL. Both patients were treated with BV and experienced a rapid and complete remission with minimal toxicity, they remained in durable remission until the time of the publication in 2013 [11].

The safety profile of BV is now well described and it is mainly represented by neurological, haematological and pancreatic toxicity. Neuropathy remains a major problem also in patients treated with HIV infection and it may be caused both from antiretroviral drugs and HIV infection. In our patient during all the first treatment period, we did not observe any neurological as well as pancreatic toxicity. Regarding hematological toxicity, a neutropenia G4 was identified after the first cycle with BV but the use of secondary prophylaxis with G-CSF bypassed this potential side effect for all the further cycles of BV. We emphasize this, because the previous experience with chemotherapy and antiretroviral drugs demonstrated a higher incidence of haematological toxicity in HIV infected patients who received both antiretroviral and chemotherapy.

Regarding infectious complications, during the first treatment we did not identify any adverse events, although CD4 counts during all the treatment period remained around 100 cells/μl, the quantitative HIV circulating RNA was always negative during the same period.

We demonstrated also that the retreatment with BV in patients with relapsed ALCL has still antitumor activity. Bartlett et al demonstrated in an open-label multicentre study, the antitumor activity of the retreatment with BV in 68% of relapsed HL or ALCL previously treated with BV [4]. The estimated median time for responding patients was 9.5 months. The rates of AEs were generally very similar to those reported in the pivotal phase 2 trials [7]. However peripheral motor neuropathy was seen higher in the retreatment than in the pivotal study. In our patient, we obtain a second very good partial response with the disappearance of the systemic symptoms and the reduction of the lymphadenopathies but unfortunately the retreatment led to more severe adverse events than in the previously primary treatment. We can explain these severe adverse events with the HIV infection status and the combination HAART and immunotherapy that could be more toxic.

Conclusions

To our knowledge this is the first case report with a patient with relapsed HIV associated ALCL retreated with BV. The progress in clinical and pharmacological research revolutionized the outcome of HIV patients with lymphomas but the toxicity remains a major problem so far. The introduction of novel less toxic drugs, as BV in HIV patients should be a future challenge in terms of evaluation of the efficacy and feasibility therefore new prospective clinical trials are expected with this population. Our experience demonstrated both efficacy and safety of BV in an HIV selected patient and that an early retreatment, even if in advanced progressive disease, seems to be associated with a clinical objective response. However, during BV retreatment these patients should be followed very closely for peripheral motor and sensorial neuropathy and for infectious complications. The confirmations of our data in major cohorts of patients are needed for overpass traditional concern about treatment of HIV infected patients.

References

1. Centers for Disease Control and Prevention (1987) Revision of the CDC surveillance case definition for acquired immunodeficiency Council of State and Territorial Epidemiologists; AIDS Program, Center for Infectious Diseases. MMWR Morb Mortal Wkly Rep. 36: 1S–15S.
2. Gibson TM, Morton LM, Shiels MS, Clarke CA, Engels EA (2014) Risk of non- Hodgkin lymphoma subtypes in HIV-infected people during the HAART era: a population-based study. AIDS 28: 2313–2318. [crossref]
3. William BM, Armitage JO (2013) International analysis of the frequency and outcomes of NK/T-cell Best Pract Res Clin Haematol 26: 23–32. [crossref]
4. Bartlett, et al. (2014) Retreatment with brentuximab vedotin in patients with CD30- positive hematologic Malignancies. Journal of Hematology & Oncology 7: 24
5. Hentrich M, et (2014) Therapy of HIV-associated lymphoma recommendations of the oncology working group of the German Study Group of Physician in Private Practice Treaning HIV-Infected Patients (DAGN&#0x00C4;), in cooperation with the GermanAIDS Society (DAIG). Ann Hematol 93: 913–21.
6. Biggar RJ, Engels EA, Frisch M, Goedert JJ (2001) AIDS Cancer Match Registry Study Group, Risk of T-cell lymphomas in persons with J Acquir Immune Defic Syndr 26: 371-376. [crossref]
7. Pro B, et (2012) Brentuximab vedotin (SGN-35) in patients with relapsed or refractory systemic anaplastic large-cell lymphoma: results of a phase II study. J Clin Oncol 30: 2190–6.
8. Ezzat HM, et al. (2012) Incidence, predictors and significance of severe toxicity in patients with human immunodeficiency virus-associated Hodgkin Leuk Lymphoma 53: 2390–2396
9. Kassahun K, et (2007) Metabolism and disposition in humans of raltegravir (MK-0518), an anti-AIDS drug targeting the human immunodeficiency virus 1 integrase enzyme. Drug Metab Dispos 35: 1657–63.
10. Rubistein PG, et al. (2015) AMC-085: A Pilot Trial of AVD and Brentuximab Vedotin in the Upfront Treatment of Stage II-IV HIV-Associated Hodgkin Lymphoma. A Trial of the AIDS Malignancy Consortium. Abstr at 57th ASH Meeting, Blood 126: 1526
11. Gandhi M, Petrich A (2014) Brentuximab vedotin in patients with relapsed HIV- related lymphoma. J Natl Compr Canc Netw 12: 16–19. [crossref]

DOI: 10.31038/CST.2017253

Abstract

Background: Cardiac hemangioendothelioma (CHE) in the adult and cardiac involvement in adult patient with non cardiac-hemangioendothelioma (NC-HE) were rare and uncommon in daily clinical experience.

Methods: We researched in PubMed, Web of Science, Scopus, Cochrane library, and Medline for identifying relevant studies, case series, review and case reports.

Results: We found 33 cases of CHE in the adult and 7 cases of cardiac involvement in NC-HE patients. According to scientific data, the most of CHE patients were female (52%), histological type epithelioid (64%), with main localization in right atrium (41%), and the main clinical diagnosis was incidentally discovered on echocardiogram. The main therapeutic choice was surgical. Otherwise the cardiac metastasis in NC-HE patients (7 cases reported) were most frequent in the hepatic hemangioendothelioma primary localization (57%) than others (spleen, bone, limb, intracranial). The most of patients were female (85.7%) and the main clinical presentation were heart failure (85%).

Conclusion: CHE and cardiac metastasis of NC-HE patients in the adult were rare and unusual neoplasms. The early diagnosis and surgical treatment in each case demonstrated an increase of patients’ survival and quality of life. We explained the scientific data to increase physician knowledge about this rare adulthood vascular neoplasm.

Keywords

Hemangioendothelioma; Primary Cardiac Tumor; Metastatic cardiac tumor; cardiac tumor; cardiac neoplasm; cardiac metastasis.

Introduction

Historical background: Hemangioendothelioma (HE) was described for the first time by Mallori in the 1908 and it was defined as a vascular neoplasms characterized by intermediate features between hemangiomas and angiosarcomas [1, 2]. With the technological evolutions, Stout and colleagues [3] studied firstly in deep the microscopic appearances in the 1943 and explained the likeness of HE to the blood vessels. In the 1967, Fernholz edited one of the first article on “Contribution of History of HE”. Only in the 1988, Enzinger and colleague defined the HE features in intermediate, borderline, or low grade malignancy.

Classification and Clinical presentation: HE was a vascular neoplasm with typical prevalent proliferation of endothelial cells and is was distinguished according to its histological characteristics as [2, 4]:

• papillary intralymphatic,
• retiform hemangioendothelioma,
• kaposiform hemangioendothelioma,
• epithelioid hemangioendothelioma,
• pseudomyogenic hemangioendothelioma
• and composite hemangioendothelioma

HE was characterised by suggestive histological feature as intracytoplasmic vacuoles, nuclear cytoplasmic inclusion, myxoid stroma, hyaline stroma and chondroid stroma (Figures 1 a and b). The most of patient had expression of vascular markers (CD 31, CD 34, ERG, FL1I) and cytokeratins (CAM 5.2, CK7, CK 18) [5].

HE involved mainly liver, lung, skin, soft tissue, bone and spleen and occurring firstly in infancy and early childhood, in the adult it was very uncommon [2].

Each of the histological types of HE had own typical presentations and patterns, such as association with lymphatic vessel proliferation as well as Kasabach-Merritt syndrome (KMS) [6-9]. KMS included thrombocytopenia, microangiopathic hemolytic anemia and mild consumptive coagulopathy, and developed often in KHE, Kaposiform lymphatic anomaly (KLA) and tufted angioma (TA) [7, 8].

HE would have different grades of aggression like:

• finite
• low aggression
• mild aggression
• moderate aggression
• severe aggression, like Kaposiform HE
  • Local to the adjoining structures
  • Metastatic

Singularly, epithelioid HE was defined in two histological grade according to its aggressiveness: classic (low-grade) and malignant (intermediate-grade) [5-55].

The progression of HE was unpredictable: sometimes it grew slowly and sometimes the tumour was more active and spread quickly [2]. The characteristics of the patients, the different clinical and spreading of HE influenced the therapeutic choices: surgical, medical or palliative.

Finally, also the mortality depended to histological type and grade of aggression and clinical correlations.

Methods

We researched english article on PubMed, Web of Science, Scopus, Cochrane library, and Medline for identifying relevant english studies, reviews, case series and case reports in the adult with the following keywords: 1) cardiac hemangioendothelioma,

2) primary cardiac hemangioendothelioma, 3) cardiac metastasis in hemangioendothelioma, 4) Cardiac Involvement in Hemangioendothelioma in the adult, and 5) Hemangioendothelioma/ Heart/ Adult. We found 272 articles with those criteria (Figure 2) and we selected and chosen 33 case reports and 7 reviews that satisfied our research criteria (Figure 2).

Figure 2. Description of scientific literature review process: first step we had researched all article in the literature

Results

According to our scientific research, the primary cardiac hemangioendothelioma was 33 reported cases. The patient age range was from 19 to 77 year-old, the average age was 45.1 ± 16.5 year-old (Table 1). The most of patients were female (n=17, 52%, Figure 3). The most common primary cardiac localization was right atrium (n=14, 41%) then the cardiac valve (n=5, 15%), left atrium ( n=4, 12%), right ventricle ( n=3, 9%), coronaric sinus (n=2, 6%), superior vena cava/ right atrium (n=2, 6%), right appendage (n=1, 3%), left ventricle (n=1, 3%), and not defined (n=2, 6%) (Figure 4). The histopathological feature of the HE in the case reported was predominantly ephiteloid (n=21, 66%), kaposiform (n=1, 3%) and defined malignant ( n=3, 9%) and not defined (n=8, 24%) (Figure 4). The clinical presentations of these patients were characterised by incidentally discovered on echocardiogram (n=11, 34.4%), dyspnoea (n=2, 6.3%), chest pain (n=4, 12.5%), alveolar hemorrhage (n=1, 3.1%), cardiac tamponade (n=3, 9.4%), incidentally discovered an heart murmur (n=3, 9.4%), arrhythmia (n=1, 3.1%), cerebrovascular event like stroke (n=1, 3.1%), widened superior mediastinum noticed on a routine chest radiograph (n=1, 3.1%), thromboembolism (n=1, 3.1%), and incidentally discovered by autopsy (n=1, 3.1%) (Figures 5 and 6). The most of patients were CD31 and CD34 positive (30.3%) and CD 99 positive (18.1%). The main therapy were the surgery (n=21, 65.6%). In the case of cardiac metastasis of hemangioendothelioma (seven reported cases in literature), the age of patients were 61.7± 12.7 year-old and they were female (85.7%). The first localization of the tumour was indicated in the Table 2. In all the cases, the patient suffered of heart failure and the most of them were undergone to surgery.

Figure 3. The percentage of cardiac hemangioendothelioma localization in the reported literature cases.

Figure 4. The percentage of cardiac hemangioendothelioma histological type in the reported literature cases.

Figure 5. Type of hemangioendothelioma

Figure 6. The clinical presentation of cardiac hemangioendothelioma in the reported literature cases were absolutely unpredictable in the adult with a major incidence of chest pain or dyspnea but wide variability in the clinical first manifestation due to patient’s health background, histological type of hemangioendothelioma and grade of aggression.

Discussion

The cardiac hemangioendothelioma was predominantly epithelioid type (66% of the cases), with a peculiar tumour site in right atrium (40% of the cases). The most of these patients were female and they had good outcome (follow up positive after 6 months in the 46.9%). In particularly, the patients undergone to aggressive and rapid surgery, were better outcome than delay diagnosis or late surgical procedure [15-45]. As reported by scientific literature, cardiac malignant tumours were rare and uncommon, especially metastatic cardiac involvement [53, 54]. Cardiac hemangioendothelioma were considered an atypical unexpected malignant cardiac tumours with high local aggressiveness and metastasizing potential [30-32, 34, 36-37].

On the other hand, we had researched the reported articled of cardiac metastasis in patient with non cardiac hemangioendothelioma reported in Table 2 [48-52]. Bisesi and colleagues [14], had already firstly documented the possibility of cardiac involvement in multifocal epithelioid hemangioendothelioma in 1996, hence we had studied in deep the scientific literature to look for other cases like this and to understand the clinical presentation and evolution of the cardiac metastasis of a hemangioendothelioma.

In our research, we had found 6 cases of cardiac metastasis of hemangioendothelioma. All of the cases were in female (100%) with a primary HE in liver (50%), one ovarian HE, one bone HE and the last intracranial HE. The most of them showed heart failure and worsening hemodynamic parameters in association with coagulative disorders and hence end–stage of multi-organ failure. The prognosis of them was unfavourable specially in the presence of coagulative disorders.

Conforming in Table 2 and our review of the literature, cardiac metastasis in patients with non-cardiac hemangioendothelioma were out of ordinary and exceptional but remarkable for the prognosis of the patients [14, 48-52].

Table 1. Cases of cardiac hemangioendothelioma in the adult reported in scientific literature. M: male, F: female, ND: non defined, RA: right atrium, MV: mitral valve, LA: left atrium, RV: right ventricle, LV: left ventricle, PV: pulmonary valve, AV: aortic valve, TV: tricuspid valve, CS: coronaric sinus, SCV: superior vena cava, F-up: follow up.

Table 2. Cases of cardiac metastasis in adult patients with non-cardiac primary hemangioendothelioma, reported in scientific literature. M: male, F: female, ND: non defined, MTs: metastasis; RA: right atrium; HE; hemangioendothelioma; IL: interleuchin; CT: chemotherapy; Pt: patient.

Conclusion

Our literature review would like to be a resume of the cardiac hemangioendothelioma and cardiac involvement in patients with non- cardiac hemangioendothelioma in daily clinical experience. In line with our analysis, the cardiac-HE was vascular aggressive neoplasm with variable histopathological pattern and outcome, principally in female patient and right atrium. Its outcome would be influenced to the early diagnosis and prompt surgical and medical treatments. On the contrary, the cardiac involvement in patients with non-cardiac hemangioendothelioma was weird and life-threatening: only seven cases described and with worsening evolution due to coagulative disorders, heart failure and end-stage multi-organ disease. In case of suspicion of CHE or cardiac involvement of NC-HE were immediately undergone to appropriate diagnostic exams (lab test, echocardiogram, computed tomography, and so on) and rapid surgical and medical therapies in order to avoid the life-threatening evolution of these malignant pathologies.

Acknowledgements: A special thanks go to Dr. Rosalba Grillo and her collaboration in the production of histological images.

Funding: none

Conflicts of interest: All the authors declare non conflict of interest.

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DOI: 10.31038/CST.2017252

Abstract

A normal cell has several processes that balance the process of self-renewal and differentiation. Multiple influences on gene expression orchestrate an orderly process resulting in normal tissue growth and function. Heritable changes in gene expression of a cell are called epigenetic changes. Epigenetics is a relatively new field in cancer studies and is increasingly being recognized to play a signification role in cancer formation and progression. Several epigenetic processes have been discovered ranging from DNA methylation to non-coding RNA. Epigenetic changes in a cancer cell are intriguing as they lend themselves to being targeted and provide avenues for cancer therapeutics.

Keywords

Epigenetics; cancer; chromatin; histone; noncoding RNA

Introduction

Epigenetics is the study of phenotypical changes occurring in a cell, with no change in the DNA sequence. The epigenetic creation of a new phenotype or state happens through specific mechanisms that affect gene expression in a stable, heritable manner. To further understand what the true meaning of epigenetics is and what it entails, a comparison to genetics is helpful. Genetics is the study of heredity and genes. Heredity is the process of passing on certain characteristics and traits through DNA from one generation to the next. In this case, phenotypes – or the traits and characteristics – are dependent upon the DNA sequence – or genotypes – an organism gets from the previous generation. Epigenetics is similar, in that it encompasses a study of phenotypes, but different, in that the phenotypes come from a heritable manipulation of the expression of DNA, not the DNA itself. This is a relatively new field that links heredity and developmental changes allowing for a deeper understanding of the ongoing changes occurring in organisms that cannot be accounted for by the DNA sequence. Figure 1 explains the difference between genetic and epigenetic changes affecting the phenotype.

Figure 1. Genetic versus Epigenetic changes affecting phenotype

Methods and Materials

A descriptive review of the various aspects of epigenetics in the context of cancer was compiled using published literature sources. This is a vast subject and our review is a concise description of basic aspects of the role of epigenetic processes in cancer.

History of Epigenetics and its role in cancer

Epigenetics is a relatively new field of genetics, with the first glimpse into it occurring in 1878, when Walther Flemming began researching organisms and their phenotypes. Flemming discovered chromosomes and the process of mitosis during cell division. He focused on cytogenetics, the study of inheriting genes and traits based on the structure of chromosomes [1]. This, combined with Gregor Mendel’s work in genetics formed a foundation for understanding of genotypes and phenotypes. At this point, many researchers started to look at how, besides genetic makeup, there was another layer (epi) to the traits and characteristics an organism has. In the 1940’s, Conrad Waddington used the term “epigenetic landscape” to represent the layer of processes that occur within cells to change how DNA is expressed to decide the fate of cellular phenotype without affecting the genotype. This process is famously visualized as a ball rolling down one of various trajectories in an undulating landscape, called Waddinton’s Classical Epigenetic Landscape [2]. Interestingly enough, researchers began comparing epigenetics to the Lamarckian evolution. Lamarck’s theory looks at how acquired traits can be passed down to upcoming generations, while epigenetics examines how “acquired traits”, or traits that occur from changes in DNA expression take place, and how they can be passed down to subsequent generations, a process referred to as ‘soft inheritance’. This may be due to heritable changes in the chromatin, such as DNA methylation, occurring as a result of environmental influences [3]. In 1983, epigenetics in relation to cancer began to call more attention, as progressively lower levels of DNA methylation was discovered to correlate significantly with progression of normal tissue to cancerous tissue and metastatic disease [4]. A few years later, portions of the DNA with clusters of cytosine and guanine nucleotides called as the CpG cluster, was shown to, when highly methylated, indicate inactive promoters. Hypermethylation of certain tumor suppressor genes was discovered suggesting a very strong link between epigenetic mechanisms and cancer [5, 6]. Enormous strides in both research and clinical trials in the field of cancer epigenetics have led to the development of many epigenetic therapies to target cancer.

Epigenetic Mechanisms Linked to Cancer

Several different epigenetic mechanisms are linked to cancer. Some prominent ones are DNA methylation, histone modification and chromatin remodeling. All of these mechanisms are present in healthy organisms, and play a prominent role in growth and development as well as adaptation to the environment.

The influence of any one of these can result in many potential health problems ranging from increased risk of obesity to cancer. For example, during the Dutch Famine of 1944-1945, pregnant mothers who were not getting enough nutrition incurred less DNA methylation of the insulin-like growth factor II (IGF2) gene promoter in their early phase embryos. This prenatal exposure of embryos persisted into adulthood as a heritable epigenetic change [7]. It is important to understand that epigenetic factors can work in numerous ways, with cancer causing factors being a pivotal research topic. Environmental influences, such as eating certain kinds of foods and exposure to carcinogens can contribute to epigenetic factors causing cancer. Unlike genetic changes, epigenetic processes are targetable and can be reversed, thus offering avenues for prevention and control of cancers.

DNA Methylation and cancer

The most well-known epigenetic mechanism is DNA methylation. This occurs when a methyl group (CH3) from S-adenosylmethionine is added to a cytosine nucleotide by DNA methyltransferase (DNMT) enzymes [8]. When a section is methylated it is typically turned “off ”, or sent to a section of the major groove in the DNA that makes it hard for transcriptional factors to bind promoters and transcribe the gene. DNA hypermethylation is a process restricted to portions of DNA that are rich in CpG dinucleotides and are part of promoters of genes [9].

Consequently, many genes are hidden from transcription factors, and therefore not expressed. Repressing genes can result in cancer due to the number of tumor suppressor genes located in hypermethylated regions. Not only are tumor suppressor genes repressed, but also, other important genes that repair DNA and regulate the cell cycle are hypermethylated, causing cancers to both form and metastasize very quickly. The table below (Table 1) gives an overview of some of the pathways and genes affected by DNA hypermethylation and their relationship to various cancers.

Amongst the most prominent and earliest described epigenetic processes leading to cancer is low level of DNA methylation also called as DNA hypomethylation. The demethylation of repetitive DNA sequences, coding regions and introns, and gene poor areas are noted to be hallmarks of carcinogenesis. These processes result in chromosomal instability, reactivation of transposable elements and loss of imprinting. It leads to mitotic recombination leading to deletions and translocations as well as chromosomal rearrangements [10]. It can lead to reactivation of repetitive DNA sequences called retrotransposons an example of which is Long Interspersed Nuclear Element-1 (LINE1). LINE-1 are implicated in carcinogenesis of epithelial tumors [11]. These are genes that comprise around 17% of the human DNA are also called “jumping genes”. They propagate themselves throughout the genome via RNA transcription and reverse transcription back into the genome and are thus called retrotransposons. DNA methylation keeps these jumping genes in check in normal cells. Hypomethylation leads to activation of these transposable genes. By inserting themselves in proximity to key genes they lead to activation of oncogenic signaling pathways [12].

Table 1. Pathways affected by DNA hypermethylation in cancer

Research suggests that hypomethylation results in activation of oncogenes, allowing cancers to form and spread rapidly. An example of this is prostate cancer, where the promoter for gene LINE1 is found to be significantly hypomethylated. This epigenetic process marks the progress of prostate cancer from localized disease to metastatic disease [13]. Global hypomethylation can affect certain tissues in the body that then go on to affect how LINE1 is transcribed. In fact, hypomethylation has been shown to result in a specific biologic signature, which marks invasiveness, and is common to breast cancer, prostate cancer and liver cancer. It utilizes major pathways such as TGF-β (transforming growth factor-beta) and ERBB2 triggered pathways [14-23].

Histone Modifications and cancer

While DNA methylation is a huge component of epigenetics; there are many other mechanisms at play. One such mechanism is chromatin remodeling which is responsible for many cancers, diseases, and conditions. To understand chromatin remodeling and cancer, it is first important to look at histones and how they affect gene expression. Histones are alkaline proteins that DNA wraps around to form nucleosomes. Nucleosomes are then tightly coiled to form chromatin, and subsequently chromatids. Naturally, because they are in such close contact with the DNA, histones play a key role in gene expression regulation. The N-terminal tail of histones undergoes posttranslational modifications (PTMs), thereby affecting the accessibility of DNA to RNA polymerase. The N-terminal tail can be changed by methylation, acetylation, ubiquitylation, and phosphorylation [24, 25]. Histone acyteltransferases (HAT’s), histone methyl transferases (HMT’s), Histone deacetylases (HDACs) and histone demethylases (KDMs) are some histone modifying enzymes performing these PTMs. An acetylated histone is comparatively looser than a normal histone, allowing for many transcription sites to become available to RNA polymerases. Increases in gene activation follow this process. Histone deacytelases (HDAC’s) support the removal of acetyl groups from the lysine amino acid in histones, allowing the DNA to tightly wrap around the histone. This results in gene silencing, as many promoter regions are hidden and cannot be transcribed. Obviously, any significant changes or mistakes in PTM’s can easily cause repression of important genes and activation of situationally harmful genes. For example, histone deacetylases act to repress the transcription of tumor suppressor genes.

Additionally, histone variants and histone chaperones are other players in epigenetic processes affecting gene expression. Histone modification processes are important for normal cellular development but can be hijacked by cancer for oncogenic signaling. This may be due to an altered histone code leading to aberrant gene expression or mutations in enzymes regulating histone modifications[26-30].

Examples of histone-mediated processes involved in cancer are presented in Table 2.

Table 2. Histone modifications in cancer

Chromatin Remodeling and Cancer

Chromatin remodeling is a dynamic process that facilitates the remodeling of nucleosomes. Chromatin modification plays an essential role in DNA replication and transcription. Tightly packaged chromatin is called heterochromatin, while loosely packaged chromatin is called euchromatin. There are four well described chromatin remodeling complexes: SWI/SNF, ISWI, INO80 and NuRD/Mi-2. By means of some key characteristic features, these remodeling complexes are able to interact with the nucleosome core, use energy from ATP, bind histones and provide grounds for biochemical alteration and protein-protein interactions [31]. For example, the switch/sucrose non-fermentable chromatin remodeling complexes (SWI/SNF) are responsible for transcription control – as well as a multitude of other tasks such as DNA repair and chromosome segregation [32]. Mutations in subunits of the SWI/SNF complex are known to occur in cancer. Malignant rhabdoid tumors are the result of the loss of INI1 subunit of the SWI/SNF complex [33].

Noncoding RNAs and Cancer

Noncoding RNAs are RNAs that are not translated into protein but play a role in gene expression and translation by various mechanims both in the normal cell and cancer. Long non-coding RNAs (lncRNAs) are non-coding regulatory sequences that have a role to play in gene expression. These are implicated in tumorigenesis by various mechanisms. They may remodel chromatin, act as transcriptional co-activators or repressors, inhibit protein, post transcriptional modifications or serve as decoy elements. Single nucleotide polymorphisms (SNPs) in lncRNAs are implicated in the heritability of several cancers including breast, thyroid, prostate and ovarian [34].

Micro-RNAs (miRNA) are short non-coding RNAs that regulate translation of transcribed genes and hence influence the phenotype of a cell. miRNA mediated pathways are implicated in several cancers including glioblastoma [35].

Table 3 summarizes the various epigenetic processes presented in this review.

Table 3. Epigenetic processes implicated in cancer

General Epigenetic Therapies

Several epigenetic therapies have been developed and approved for use in various malignancies. Several novel epigenetic therapies are in the process of preclinical and clinical development. DNMT inhibitors are the first epigenetic therapy approved for clinical use for their therapeutic role in myelodysplatic syndrome and acute myeloid leukemia,

HDAC inhibitors are approved for use in T cell lymphoma and multiple myeloma.

Several other epigenetic targets have been identified and their inhibitors are in preclinical and clinical development. These include bromodomain, EZH2 (enhancer of zeste homolog 2) and DOT1( disrupter of telomere silencing protein 1) inhibitors [36].

Conclusion

The role of epigenetics in cancer is prominent and clear. This relationship is apparent through the multiple epigenetic mechanisms implicated in cancer: DNA methylation, histone modifications, chromatin remodeling, and non-coding RNA. All of these mechanisms have been proven to significantly impact the epigenome, without impacting the DNA itself. DNA methylation can occur in a surplus or a deficit, both of which can consequently create and promote cancer within the body. Histone modifications alter the space in which DNA resides, therefore making it harder or easier for that

DNA to be transcribed. Chromatin remodeling affects the degree to which specific sites of DNA are bound, which decides to what extent certain genes are expressed. Long non-coding RNA is a more recently discovered major epigenetic mechanism regulating gene expression. While epigenetic mechanisms can result in cancer formation, research underway holds promise of using the same mechanisms to combat cancer.

Acknowledgements: The authors would like to thank Dr. Sunil Sharma and the Center for Investigational Therapeutics at Huntsman Cancer Institute for their support and providing the opportunity to learn.

Funding information: Support for the publication of this manuscript was provided by the Huntsman Cancer Institute/Huntsman Cancer Foundation.

Conflict of Interest: The authors have no competing interests with regard to this review.

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DOI: 10.31038/CST.2017251

Abstract

Investigations in immunomodulating therapies for cancer treatment over the past 20 years have flourished. Given the complex tumor microenvironment and differential signaling pathways a wide variety of potential targeting mechanisms have come to attention. Herein we review the immunomodulating potential of Chemokine 21 in pre-clinical and clinical studies, as well as examine the novel multi-faceted immune-based treatments in advanced head and neck cancer.

Introduction

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer in the world, accounting for more than 300,000 deaths annually [1]. Despite advances in surgical techniques and chemo-/radiation treatment strategies, patients with advanced T3 or T4 HNSCC continue to demonstrate 20%-30% survival with failure of primary surgical or medical (radiation and chemotherapy) management. Salvage therapies, in recalcitrant or recurrent disease, are limited by systemic toxicity or operative morbidity owing to nearby vital structures (carotid artery, skull base). Immunotherapy and modulation in HNSCC is a promising venture given recent advances in cancer biology and investigations in the tumor microenvironment.

Historically studied in the contexts of inflammation and immune response, chemokines have increasingly been studied in the context of tumor proliferation [2, 3]. Chemokines are a family of small chemotactic cytokines involved in cellular signaling and inflammation. Through interactions within a subset of G-protein- coupled transmembrane receptors (GPCRs), secreted cellular chemokines regulate cellular homing, activation, and recruitment of a variety of diverse leukocytes and activated adhesion molecules [2, 4-6]. In the tumor microenvironment, responses to specific chemokines result in the migration of different immune cell subsets and regulate tumor immune responses; these are both pro- and anti- inflammatory in nature. Chemokines, have been directly associated with cancer immunity, proliferation, and metastases [7,8]. In this review, we address the role of Chemokine 21 (CCL-21) in tumor progression, its role as an immunotherapy platform, and the potential within head and neck oncology.

CCL-21 chemotaxis and lymphocyte recruitment

Divided into four subfamilies, chemokine nomenclature is related to the location of their first N-terminal cysteine (C) residues; classified as: C-, CC-, CXC-, and CX3C-chemokines [9]. CCL-21 (also known as Thymus-derived chemokine 4, 6Ckine, or Exodus-2) is a CC chemokine expressed in high endothelial post-capillary venules, T-cell stromal zones of the spleen, Peyer’s patches, and afferent peripheral lymph nodes that strongly attracts naïve T-cells and mature dendritic cells (DC) including NK T-cells [10-13]. The effects of CCL-21 on chemotaxis have been demonstrated in neutralization studies, where the homing of T-cells and DCs has been shown to be significantly reduced [14, 15]. Acting through the GPCR CCR7, a convergence of the immune response elements to sites of CCL-21 production have been demonstrated to co-stimulate the expansion of CD4+ and CD8+ T cells and induce Th1 polarization [16]. Additionally, chemokine bound DCs form T cell adhesions resulting in a hyper-responsive T-cell on subsequent exposure to CCL-21 and antigen-presenting cells [17].

Role in cancer immunotherapy

The cancer immunosuppressant microenvironment results in ineffective antigen processing and presentation; resulting in poor host response. The CCL-21/CCR-7 axis has been studied in efforts to create a more immunogenic environment through chemotaxis of DCs, NK cells, and lymphocytes. By recruiting host antigen presenting cells (APC) for tumor antigen presentation, T cells within lymphoid organs have the ability to prime anti-tumor specific activity. Of note, while CCL-21 aids in the polarization of Th1 lymphocytes, the secondary lymphoid chemokine has also been shown to have minimal effect on the proliferation of suppressor cell population; CD4+CD25+ T-regulatory cells are hypo responsive to CCL-21 induced migration and unresponsive to CCL-21 co-stimulation [16]. High levels of T-regulatory cells within the tumor microenvironment has demonstrated poor prognosis in many cancers, dependent on the type and location of neoplasm [18].

Pre-clinical animal models

The ability to process and present a high ratio of activated tumor-antigen-APCs has long been the goal of immunotherapy in the immunosuppressive cancer microenvironment. The first established model for the creation of a CCL-21 chemotactic gradient in restoring tumor-antigen presentation was undertaken by Sharma and Dubinett [19]. In an immune competent murine lung cancer model, intratumoral injection of CCL21 induced infiltration of CD4+ and CD8+ T cells and DC in both tumor and draining lymph nodes. Additionally, a potent antitumor response was observed as complete tumor eradication was found in 40% of treated mice [19]. Furthermore, the tumor microenvironment displayed a concomitant decrease in immunosuppressive molecules such as PGE-2 and TGF-ß [19]. When introduced to the afferent axillary lymph nodes, CCL-21 injections resulted in a marked infiltration of lymphocytes and DCs into the lung tumor microenvironment, associated with a significant reduction in tumor burden [20]. The anti-tumor efficacy of CCL-21 has further been confirmed in a variety of transgenic lung, ovarian, melanoma, and liver cancer models [21-25]. Despite the promising results, in vivo studies have utilized specific cancer cell lines, with greater success observed in low-malignant weakly metastatic clones as compared to highly-metastatic clones [26]. Further research on the efficacy within specific tumor phenotypes, locations, timing, and dosing of CCL-21 continues to be underway.

Antigen presenting cells as a platform

APCs are fundamental in the activation of specific immunity and have been investigated as adjuvants to cancer immunotherapy to stimulate tumor-specific antigen presentation for promotion of T cell activation and anti-cancer immunity [27, 28]. Prior investigations have generated DCs with enhanced immune stimulatory and T-cell activity through pulsed electroporation of antigens or viral transduction of cytokines [29-33].

A platform to transduce DCs with CCL-21 (DC-CCL21) through an adenovirus vector has also recently been developed demonstrating viable in vitro chemotaxis of activated lymphocytes [34, 35]. The anti- tumor efficacy of DC-CCL21 has been studied in the murine lung and melanoma cancer models. These studies demonstrated a significant reduction in melanoma tumor growth and complete eradication of lung tumor burden in 60% of mice with lung cancer [32, 34]. Clinical trials are currently underway in late stage non-small cell lung cancer patients based on the promising results of this preclinical data [36].

Head and neck oncology

Recurrent and advanced HNSCC has been extraordinarily challenging to treat, with stagnant survival and cure rates over the past 20 years [37]. Depending on the tumor site, reoccurrence rates may range from 25%-50%, and the incidence of subsequent reoccurrences similarly fall within this broad range [38-40]. Morbidity from current salvage treatment strategies are unfortunately common and include chronic pain, respiratory distress, and dysphagia oftentimes resulting in tracheotomy, or, gastrostomy tube dependence [41]. Despite cancer outcomes, cosmetic and functional deficits may negatively impact the head and neck cancer patient’s quality of life [42-44]. Limited surgically by nearby structures and systemically by toxic effects, advancements in locoregional therapies in the tumor microenvironment are strongly desired.

Recent advances in material science, have developed biocompatible, functional, three dimensional polymer systems for molecular and cellular delivery in cancer care [45]. A novel implantable polymer- based system for the delivery of chemokines to interact directly with tumor cells, has the potential to integrate with a wide range of anti- cancer treatments. Recently, a biodegradable poly-ε-caprolactone (PCL), polylactide-co-glycolide (PLG), co-polymer seeded with DC- CCL21 and/or cisplatin has been tested in an animal model resembling unresectable head and neck squamous cell carcinoma (HNSCC) [46, 47]. Tumor cells from the squamous cell carcinoma (SCCA) VII/ SF were injected, grown, and debulked in the flanks of C3H/HeJ mice. The animals then underwent debulking surgery to replicate an unresectable cancer setting. The flexible seeded PCL/PLCL polymer was then applied to contour the cancer tissue bed. In the first study, the cisplatin-polymer group effectively reduced tumor volume by over 16-fold when compared to control polymer with intratumoral cisplatin injection groups [47]. When combined with radiation, the cisplastin-seeded polymer group enhanced the efficacy of radiation therapy by tumor volume reductions of 53% when compared to surgery and radiation alonel [47]. Given the well-established literature in the role of cytokines in tumor regression, the HNSCC murine polymer model was then seeded with DC-CCL21 using a fibrin gel delivery mechanism. After implantation to the partially resected tumor, DC-CCL21 secreting polymer significantly reduced SCC VII/ SF tumors by 41% as compared to control groups [46]. Additionally, the DC-CCL21 polymer resulted in increased CD4+ and CD11+ DCs as well as a marked decrease in T-regulatory cells within the tumor microenvironment.

Current studies are underway to assess the anti-tumor efficacy of DC-CCL21 with combination of cisplatin and radiation therapy in the HNSCC murine model. Additionally, the promising findings of APC and T cell recruitment provide the rationale for combination with immune checkpoint blockade therapy to enhance the frequency of activated T cells in the tumor micro-environment for improved patient outcome.

Conclusion

Research in the field of immunology has evolved tremendously as the complex immunosuppressive tumor microenvironment continues to unravel. The role of CCL-21 is critical in promoting DC homing and T-lymphocyte activation. Tumor antigen presentation is significantly amplified both locally and peripherally following introduction of CCL-21. Head and neck cancer therapies, previously limited by morbidity,
may now have an alternative for locoregional control in unresectable tumors. A multi-faceted approach to innovative cancer treatment is necessary in order to maximize the immunogenic potential for tumor cell death. As described, it is clear that CCL-21 is a potent chemokine in eliciting an immune response with substantial evidence supporting its use in future oncologic therapies. Collaborations with materials scientists, immunologists, and physicians can not be underestimated in the ongoing pursuit for cancer cure.

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DOI: 10.31038/CST.2017247

Abstract

Nothing makes sense except considering evolution, by which understanding how life originates it is important to be able to decipher the mysteries that lead to the abnormal behavior of the cancer cell. So far, the emergence of life is explained in religious terms, but in scientific terms, it was not possible. The various existing theories had gaps that could not be resolved. The discovery of unsuspected capacity of melanin transform light into chemical energy, such as chlorophyll in plants; It is a watershed in biology, it turns out that melanin is the missing link in the chain of events that leads to the emergence of life. Now the Outlook is different, we can advance faster in the study and treatment of diseases that currently constitute a scourge to mankind, such as cancer. We are on the threshold of a new era in biology and in medicine.

Introduction

The unsuspected bio-energetic role of melanin has been described previously [1]. Electromagnetic radiation, melanin and water are substances that do not present any data that allow us to think that they have some thought as an evolution process. You could say that its main physical and chemical characteristics are the same since the beginning of time.

What we call evolution, can realize to the biochemical scaffolding that nature has patiently developed over eons of years, to increasingly optimize the properties of light, melanin and water, which have not changed a whit.

Eukaryote cell is becoming more sophisticated, biochemical gear is increasingly complex, and what is most striking, the power supply remains the same since the beginning of time. This is: the first living entities, had similar amount of available chemical energy derived from the melanin that human beings today.

It is something that has not changed despite the passage of time. What, has changed continuously over time, is the number of molecules, organelles, enzymes, etc., have been bolted together to make increasingly more sophisticated, increasing the complexity of the cell. And the term sophisticated, applied to any system; means that it contains many parts.

Continues to call me the attention that the power source is still, on the one hand, the sunlight mainly, on the other hand, melanin, which has not changed in the slightest despite the course of millions of years; and so on the perfect substrate which is water.

It is interesting that one of the elements, melanin; is completely dark and we can’t see through it, either with the naked eye or with instruments, and to this we attribute the fact that its formula is not known. But, on the other hand; water is completely transparent, we observe it with the naked eye, and yet we don’t understand as the hydrogen and oxygen atoms that compose it are organized, due to diverse factors, i.e. because its arrangement is dynamic and not uniform.

The nature of light, we neither speak, don’t even understand if it is a wave or a particle, or both. So, from three natural phenomena which we know little or nothing, life originated. Melanin is the missing link between the different theories that try to explain how emerged those we named life.

Light, Melanin, and Water

The physical and chemical properties of light, melanin and water whether we understand them or not, they possess characteristics that seem to be immutable, they inner dynamic had not change in the slightest despite the passage of time. And it seems paradoxical that the union of these quite stable elements generates the very dynamic phenomenon that we call life; which is characterized by constant changes, in all times, everywhere.

Charles Darwin said that life originated in warm water, with low oxygen levels, and without any other form of present life. And it is all spent out there, because the amniotic fluid is warm water with low oxygen levels and without any other way of life.

The evolution of the human eukaryote cell, requiring billions of years of evolution, based on primitive cells, is repeated in each pregnancy, and reducing days. Thus, the initial cells during pregnancy are primitive cells, whose structure is not as complex as mature or specialized eukaryote cell.

But despite differences that may be, at least in appearance; different cell lines retain the same fundamental process of generation and distribution of energy from the melanin.

In eukaryotes normal cells, of any cell line; organelles are very similar, even in size; which reflected a surprisingly uniform pattern, which cannot be a result of chance. And that consistency comes from the origin of life, as both light, melanin, and water, are very dynamic elements but do not change, do not seem to evolve in the least; It seems that they reached perfection and do not need to go further.

What if it evolves, and does so constantly, all the time, is what we call life. And one of the features of the evolution, is the increasingly complex management, in many respects, from the chains of carbon mainly from photosynthesis-derived glucose, this is: a homogenously arrangement of carbon, oxygen, and hydrogen atoms, with C_nH_2nO_n as general formula, and whose most soluble example is glucose. While more advanced is a cell in the evolution, more efficient is the way in which atoms and carbon chains entwine each other forming increasingly intricate and complicated processes and structures, but in the end, reflects an increasingly efficient use of the energy that emanates from the melanin in the form of molecular hydrogen and high-energy electrons. A kind of energy astonishing accurate.

The proliferative cell

It is a deep-rooted dogma that normal differentiated cells, rely primarily on mitochondrial oxidative phosphorylation to generate energy needed to impel cellular processes.

So, it is not surprising that the metabolism of embryonic cells present findings consistent with the Warburg effect [2], or aerobic glycolysis. Which is an inefficient way to generate adenosine 5´-triphosphate (ATP), allowing to incorporate nutrient into biomass, rather than efficient and too much complicated, ATP production.

However, mitochondria and ATP biological functions are regulation of temperature and phosphate levels, but no energy production. Therefore, ATP biological function is regarding temperature control and phosphate levels, compounds that are chemically unstable but thermodynamically stables.

Thereby, embryonic cells require generating biomass so quickly, and gradually more and more complicated processes appear inside these cells, reflected, i.e.; by the increasing mitochondria number, whose function is the temperature control as much as possible, due to the chemical reactions inside normal differentiated cells are astonishing accurate, and temperature is no exception.

By other hand, uncontrolled proliferation is due to the cells that turn back in evolution, being the explanation due to the generation and distribution of melanin´s energy has been affected chronically.

Cancer cells are not generally controlled by normal regulatory mechanisms [3]. Thereby, the characteristic disordered tumor growth is dependent of difficult-to-understand mixture of local factors. A good example are the processes involved in angiogenesis and vascular remodeling implied in the vascularization of malignant tumors.

Total spectrum of morphogenic and molecular events required to form a neovascular network are way beyond our abstraction capacity, because casualness is a significant factor. And worst, those events are significantly different of normal vasculogenesis.

But in the light of the bio-energetic unsuspected role of melanin, we can reconsider such processes initiating the analysis as follows: the blood cannot carry energy, and on the other hand, the amount of chemical energy available in a cancer cell, is significantly lower than in a normal cell, therefore we have a series of events that reflect a step backwards in the evolution of the diseased cell and their chemical and anatomical, physical characteristics indicate that address.

While more evolved it is a cell, its operation is farther from random, and vice versa.

The intricacy of the processes that make up a specialized cell, they make these increasingly more and more precise, and one of the purposes of evolution is gradually reducing the interference of random in intracellular biochemical processes. Since any alteration in its sequence, temporality, or spatial location, would have devastating effects on perfectly than a specialized eukaryote cell represents.

Anti-vascular therapy of cancer

It has been over 30 years since Judah Folkman hypothesized that tumor growth is angiogenesis dependent [4]. But after years of clinical trials based in Dr. Folkman theory, results have been disappointing. Inhibition of VEGF, the main molecular mediator in capillary sprouting has been insufficient to halt tumor progression permanently in many cancer types.

The reasons can be diverse. i.e. the existence of multiple vascularization mechanisms and additional growth factor pathways. In our experience, the main cause of this failed therapeutic focus is that blood cannot carry on energy, just cell´s building blocks as glucose, aminoacids, lipids, etc., and CO₂.

Cancer cells

Most solid tumors display distinct aneuploid karyotypes (abnormal chromosomal numbers) and frequently miss-segregate whole chromosomes in a phenomenon called chromosomal instability (CIN). CIN positively correlates with poor patient prognosis, indicating that reduced mitotic fidelity contributes to cancer progression by increasing genetic diversity among tumor cells [5].

Mechanisms leading to the loss of mitotic fidelity in CIN are not known. A common mitotic defect in tumor cells with CIN is the persistence of erroneous attachments of chromosomes to spindle microtubules (merotely).

In normal diploid cells erroneous attachments arise spontaneously and are efficiently corrected to preserve genomic stability. Paradoxically, kinetochore microtubule attachments in cancer cells with CIN are more stable than those in normal diploid cells, thereby, accounting for the persistence of mal-attachments into anaphase, causing chromosome miss-segregation. Seems that cancer cells have a diminished capacity to correct erroneous kinetochore-microtubules attachments; a dysfunction with a widespread occurrence of CIN in tumors.

The mechanisms involved in ploidy protection and genomic integrity are highly complex, not understood, and astonishingly accurate. In example, initiation of a new round of DNA replications should be restricted until after completion of the previous mitosis. Thereby DNA replication depends of biochemical pathways that occur exactly in time, space, location, amount; etc., in an amazing way; but are largely unknown.

The failures in these poor-understood regulatory mechanisms are generalized. Therefore, the plausible explanation is energy. Other theories proposed in the scientific literature, trying to explain abnormalities observed in cancer cells, has been proved elusive, given the inherent complexity of specialized eukaryotic cell after four billion yeas of evolution.

However, we are in front of a new era in the molecular biology of cancer cells; thanks to unsuspected bio-energetic role of melanin. And the explanation seems as quite simple: a specialized eukaryotic cell whose levels of generation and distribution of energy (from melanin) are impaired by contaminated water, polluted air, pesticides, herbicides, fertilizers, transition metals, heavy metals, addictive drugs, solvents of diverse types, industrial waste, stress, etc., tends to turn back in evolution. Simply because the complicated biochemical cell scaffolding that gives vital and highly-ordered support to the poorly understood specialized eukaryotic cell, requires astonishingly accurate amounts of energy.

Insofar as the available quantities of energy inside the cell to reduce enough, for example, in time and form, the very complicated biochemical pathways start to collapse in a disorderly way. Apparently, keeping only the most basic functions; or at least the first that appeared during the evolution, which gives us an idea that cell not is being able to keep relatively recent occurrence mechanisms.

In humans, aneuploidy is linked to pathological defects such as development abnormalities, mental retardation, or cancer, but the underlying mechanisms remain elusive. There are many types of aneuploidy whose origin remains unknown. A common response independent of the type of aneuploidy can be a novel target for cancer therapy.

Genomic stability requires that genetic material must be equally distributed between the two daughter cells during mitosis. An apparently straightforward process, by far beyond our abstraction capacity. By other side, an aberrant number of chromosomes, or aneuploidy, has been recognized as a feature of human malignancies for over a century, but until today without compelling evidence of causality.

Molecular logic underlying proper and aberrant chromosome segregation are extremely complex. It is undoubtedly that chromosome instability is detrimental for the fitness and survival of normal cells, being also the hallmark of cancer cells. Paradoxically, cells with an elevated proliferative potential, are also highly aneuploid.

Theoretically, Aneuploidy is a direct consequence of chromosome segregation errors in mitosis, while structural aberrations are caused by improperly repaired DNA breaks, but also exists a cross-talk between them. The long-lasting efforts to selectively inhibit proliferation of tumor cells has been infructuous.

Toxins against microtubules exert anti-tumor effects in some patients, but it is unclear its action´s mechanism. Apparently, these compounds acts interfering with microtubule dynamics during mitosis activates the spindle checkpoint, causing a prolonged mitotic arrest. Thereby, cells either then undergo death in mitosis or slippage; returning to interphase without dividing; but it is unclear what dictates the balance between these two fates.

Therapeutic inhibition of major mitotic kinases and kinesins has given a modest clinical activity at best.

Thereby, the maintenance of chromosomal stability involves the whole cell, not only genes. So, generation and distribution of energy from melanin has a fundamental role in cell biology (Figure 1).

Figure 1. Diagram of the hitherto unknown intrinsic capacity of melanin to transform visible and invisible light into chemical energy, dissociating the water molecule, as chlorophyll in plants.

The energy that melanin provides incessantly, night and day, in a quite consistently form, both in and outside the cell, explains finally, the origin of life.

In chlorophyll, the water dissociation is irreversible; but in melanin is reversible. The process is as follows:

2H₂O → 2H₂ + O₂ →2H₂O + 4e^–

The liquid water is sublimated by melanin into its gaseous components molecular Hydrogen (H₂) and Oxygen (O₂) in astonishing and accurate way, this is: always the product of the water dissociation is molecular hydrogen and molecular oxygen. Thereby, it is a quite precise process even in a diversity of environmental conditions, because melanin acts also as attemperator of surrounding sudden changes, for instance, a significant increase or decrease in the amount of light; keeping the output of H₂ and O₂ between narrow ranges.

The biochemical process of cell (and body) is amazing accurate, otherwise life is not possible; but this astonishing precise start since the very first step of life that is the energy production. Evolution can be interpreted as the increasing and gradual organization of the distribution of energy that is more and more exquisite, efficient; and precise as time pass by. Recall that is the same energy since the beginning of time, both in nature and amount.

The specialized eukaryotic cell does not generate more energy from melanin, because melanin energy generation has a top, a guarded proportion; unless more melanin is added to the system. Instead it is much more efficient in the distribution and thereby using of H₂ and e- that the melanin dissociation and re-formation of water produces constant and exactly during night and day.

Eukaryote cell, mature, specialized; It is a whole that works perfectly in every one of its parts, starting from the generation and distribution of energy; which has been patiently optimizing over millions of years of evolution. You could say that nothing or almost nothing of what happens inside a specialized cell is the result of chance.

In any system, not only in biology; energy, defined as everything that produces a change; It is the most sensitive segment as an alteration in this area produces widespread failures, such as that seen in cancer cells.

Hence how difficult that has been to develop a successful therapy in cancer cells, it seems virtually impossible, because when designing strategies that act on a certain part of the cell, for example microtubules; the cell simply changes its behavior, which is now largely influenced by random, totally opposed to a normal cell; and quickly becomes resistant to instituted treatment.

And the explanation is that simply the imbalance now is expressed differently, but the actual background of the problem doesn´t change, and the proof is that proliferation does not diminish. Many of the deviations observed in a cancer cell should be taken care at the same time, so cell tends to function normally, as it has millions of years, millions of times.

Experiments in this regard have shown that partial reparation of the altered intracellular processes is not the solution, it is necessary to address the entire e ideally at the same time.

This is not currently possible, except to increase the generation and distribution of energy that comes from the melanin, and since all the biochemical processes that occur inside the eukaryote cell depend entirely on the H₂ and e^–, to normalize these levels, all processes tend to operate normally, because ultimately, they are chemical reactions quite exact, that may not happen or inadequately occurs if the power level is not suitable.

QIAPI 1^® and Cell Proliferation

The following Tables (1-4) show results of experiments carried out in cultured human cells. The results are part of the development of medication implemented in our laboratory, and which is in phase of patent in several countries, which has already been granted in several of them.

Table 1. WI-38 (human diploid cell line from normal embryonic (3 months gestation) lung tissue)

Table 2. A549 (human lung adenocarcinoma epithelial cell line)

Table 3. HS 683 (human neuronal glioma cell line)

Table 4. Inhibitory concentrations of QIAPI 1^®.

These results present them as a proof of concept, since the mechanism of action of QIAPI 1^® is intensifying the dissociation and reformed the water, by the melanin molecule. (Tables 1-4)

The similarity in the results, although cultures of different cell lines, support our theory that acting on the generation and distribution of energy, cells, regardless of human classifications, they tend to recover complex order that is required so that their behavior is normal, proper; as millions of years, has done millions of times.

QIAPI 1^® is a new therapeutic agent [6] that gradually will appear in the market, as legal requirements should be fitted.

Conclusion

The apparent chaos that reigns in efforts to decipher the bases of the anomalous behavior of cancer cells, appears to take a totally different direction when we do aside dogma that the main source of cell energy is glucose, then the discovery of unsuspected intrinsic property of melanin make visible and invisible light into chemical energy, such as chlorophyll in plants; through the dissociation of the water molecule, it is a watershed in cell biology.

We have a new view in the study of the biology of cancer, and while we move faster in that sense, the benefit that can give every day to numerous patients affected by the disease will be higher.

Acknowledgement: This work was supported by Human Photosynthesis® Research Center.

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