Development of a Protocol for Obtaining a Homologous Cell Product of Animal Origin Intended for Preclinical Studies of Antitumor Vaccine CaTeVac.

When developing a program of preclinical studies of human cell-based drugs intended for adoptive immunotherapy of cancer patients, the biological effect should be substantiated by data describing their immunological action. Administration and study of human autologous dendritic cell vaccine to immunocompetent animals are not adequate in terms of immunological compatibility. It is possible to use immunocompromised, knockout, or transgenic animals or to obtain a homologous cellular product, namely, a preparation based on animal cells using a technology similar to obtaining the original preparation for clinical practice in humans. Within the framework of this study, we have developed a protocol for obtaining a homologous cell product based on animal dendritic cells (mice, rats) according to a similar technology for obtaining human vaccine dendritic cells, and demonstrated the comparability of morphological characteristics and expression of differentiation antigens of dendritic cells (CD11c, CD80, CD86, and CD83) of animals (mice) and humans.

Significant difference in response of malignant tumor cells of individual patients to photodynamic treatment as revealed by digital holographic microscopy.

The investigation of in-vitro response of cell cultures derived from tumor material of individual patients with similar tumor localizations to photodynamic treatment is presented. Tumor types included in the research were renal cell carcinoma, melanoma and alveolar, synovial, lypo- and osteo- sarcomas. Long-term observations of treatment-induced morphological changes in cells were performed by means of digital holographic microscopy. A substantial variance in response of cells of individual patients with similar tumor types and localizations to photodynamic treatment with the same dose has been observed. These peculiarities are indicative of the demand to personalized protocols of photodynamic treatment. The elevated resistance of cells of some patients to treatment at high doses highlights potential limitations of photodynamic therapy for some patients. Digital holographic microscopy is shown to be an informative label-free noninvasive tool allowing for long-term monitoring of cell samples in vitro and providing quantitative information on necrosis rate and loss of cellular dry mass. The developed methodology can be generalized for analysis of cellular response to various therapies.

Clinical and immunological characteristics of sarcomas patients with clonogenic tumors.

Tumorigenesis is related to the generation of heterogeneous tumor cell population, which is the result of genetic and epigenetic alterations followed by clonal selections and subsequent expansion. In basic studies genetic, histological and morphological diversity of different clones within a patient's neoplasm and specifics of their interrelation with patient's immune system are investigated mostly on the models of tumors of epithelial origin. Mesenchymal tumors such as soft tissue and bone-derived sarcomas (STBS) have been poorly studied in this regard. The molecular genetic methods used to examine intratumoral heterogeneity do not currently provide insight into which portion of the identified subclones are able to grow autonomously. Limiting dilution cloning demonstrates the existence of self-regulating tumor cells in the population and can serve as an independent prognostic predictor of poor prognosis. Intratumoral heterogeneity results not only in differences in growth dynamics, gene expression, and phenotypic markers, but also in the resistance to treatment, especially immunotherapy, thus causing tumor eluding immune escape. The changes that accompany this process can be affected by the cellular immune system, resulting in an imbalance between populations. The variations in the population composition of immune system cells are now widely debated as a predictor of response to immunotherapy, which is of obvious interest for sarcomas, where the effectiveness of chemotherapy is low and the prognosis is unfavorable, especially in case of metastatic disease development. The search for new predictive markers of disease prognosis and treatment efficacy is an important task, to which this study is focused. Our results demonstrate that clonogenic tumor characteristics such as clonogenic potential is independent predictor of unfavorable prognosis in cases of cancer and correlate with the clinical characteristics of the tumor such as overall survival (OS) and progression free survival (PFS). It was found that patients with clonogenic sarcomas had a lower content of activated cytotoxic T-lymphocytes (CTL) with the CD3+CD8+HLA-DR+ phenotype and an increased number of natural NK killers (p < 0.05) compared to nonclonogenic tumors. In addition, according to our data, a high neutrophil to lymphocyte ratio (NLR), a low value of major T-lymphocyte populations, and a higher number of natural killer cells (NK) in the blood can be negative prognostic factors for the immunotherapy of this disease.

Biological features of tissue and bone sarcomas investigated using an in vitro model of clonal selection.

The malignancy progression is an evolutionary process in which tumor clones are selected and competed for the duration of the disease. Intratumor heterogeneity is one of the key problems in the development of treatment methods for cancer patients. In this study we obtained metastatic soft tissue and bone sarcomas (STBSs) cultures from 54 patients, performed in vitro cloning and randomly selected 83 clones. Cloning was successful in 22 cases (40.7%). STBSs cultures with a high clonogenic potential (CP) were characterized by greater proliferative activity and increased Aldehyde dehydrogenase (ALDH) expression. We studied the transcription activity of the following cancer-testis genes (CTG): MAGE, NY-ESO-1, PRAME, GAGE, SSX1, HAGE1, PASD1, SCP1, SEMG1, SLLP1 and SPANXA1. The SEMG1 expression wasn't registered in any studied case. CTG activity wasn't observed in 10 cases out of 52 (19,2%) STBS cultures. We observed CTG activation and increased transcription activity in 82 STBSs clones. Clustering by the gene profile has revealed three different patterns: 1 st - with low expression CTG, 2nd - with co-expression GAGE1, PASD1 and PRAME, 3d - with co-expression SLLP1 and GAGE1. The last two clusters included most cloned cell lines and their clones. CP of STBSs cell lines was associated with the parameters of patients overall survival (OS) at comparable progression-free survival (PFS). Among patients with STBSs with the high CP, median OS was 7.6 months (min 0.7 - max 11.0 months). In the group with the low CP, OS did not reach the median value by the end of the five-year observation period. PFS was 5.6 months (min 0.2 - max 19.2 months) in the first group and 3.2 months (min 0.3- max 71.3 months) in the second group. Resistance to therapeutic doses of chemotherapy drugs was correlated with CP cultures STBSs. We suggest that chemotherapy-resistant clones are pre-existing in the tumor rather than being formed under the influence of chemotherapy. Highly aggressive metastatic sarcomas may be a promising candidate for immunotherapy against cancer-testis antigens (CTAs).

Exploring bioactivity potential of polyphenolic water-soluble lignin derivative.

Many natural substances exhibit anti-inflammatory activity and considerable potential in prophylaxis and treatment of allergies. Knowing exact molecular targets, which is required for developing these as medicinal products, is often challenging for multicomponent compositions. In the present study we examined novel polyphenolic substance, a water-soluble fraction of wood lignin (laboratory code BP-Cx-1). In our previous study, a number of polyphenolic components of BP-Cx-1 (flavonoids, sapogenins, phenanthrenes etc.) were identified as the major carriers of biological activity of BP-Cx drug family, and several molecular targets involved in cancer and/or inflammation signaling pathways were proposed based on the results of the in vitro and in silico screening studies. In the present study, half maximal inhibitory concentration (IC50) of BP-Cx-1 was established with a radioligand method and a range of IC50 values between 22.8 and 40.3 µg/ml were obtained for adenosine receptors A1, A2A and prostaglandin receptors EP2, IP (PGI2). IC50 for serotonin 5-HT1 and for glucocorticoid GR receptors were 3.0 µg/ml and 12.6 µg/ml, respectively, both being within the range of BP-Cx-1 concentrations achievable in in vivo models. Further, distribution of [3H] labelled BP-Cx-1 in NIH3T3 murine fibroblasts and MCF7/R carcinoma cells was studied with autoradiography. [3H]-BP-Cx-1 (visualized as silver grains produced by tritium beta particles) was mainly localized along the cell membrane, in the perinuclear region and in the nucleus, suggesting ability of BP-Cx-1 to enter cells and bind to membrane or cytosol receptors. In our experiment, we observed the effect of BP-Cx-1 on maturation of dendritic cells (DCs): downregulation of expression of the lipid-presentation molecule CD1a, co-stimulatory molecules CD80, CD83 and CD 40, decreased production of pro-inflammatory cytokines IL-4 and TNF-α and increased production of anti-inflammatory cytokine IL-10. It is hypothesized that [3H]-BP-Cx-1 detectable in the nucleus is part of the activated GR complex, known to be involved in regulation of transcription of genes responsible for the anti-inflammatory response. Based on IC50, cell distribution data and results of the experiment with DCs it is suggested that the in vivo effects of BP-Cx-1 are mediated via GR and 5-HT1 receptors thus promoting development of tolerogenic effector function in dendritic cells.

[Neutrophils as tumor microenviroment member].

Conception of the neutrophils role in the immune system has been changed significantly in the recent time. Many studies prove important and diversified role of this cells in the cancer biology in the last few years. It was shown that their presence in tumor microenvironment has mixed role on cancer growth. This review summaries evidence of neutrophils heterogeneity, plasticity and ability to differentiate into other myeloid types of cells despite formed proinflammatory potential. Prognostic value of tumor-associated neutrophils and high neutrophil level in peripheral blood in patients with different type of malignancies (i.e. renal cell cancer, melanoma, colorectal cancer, hepatocellular cancer, cholangiocarcinoma, glioblastoma, gastrointestinal stromal tumors, gastric cancer, lung cancer, ovarian cancer, head and neck cancer) is discussed. More sophisticated study of existence and functional activity of pro- and antitumor abilities of neutrophils is needed for finding new diagnostic and therapeutic approaches in oncology.

[Modeling of the impact of chemotherapeutic agents on primary cultures of metastatic soft tissue sarcomas in the automated analytical system CELL-IQ].

This work presents results of long-term phase-contrast microscopy research of proliferative potential of soft tissue sarcomas utilizing live-cell imaging technology Cell-IQ (Chip-Man Technologies Ltd, Finland). It was found that the machine vision technology allowed to obtained sufficient body of evidence about high-quality and quantitative changes of proliferative activity of the cells soft tissue sarcoma cultivated in static conditions. The present study demonstrates that modeling in time interval of maximum proliferative activity of soft tissue sarcoma cells increases information efficacy and reliability of the analysis of dividing cells patterns using Cell-IQ technology. The models of exponential growth of tumor cells soft sarcomas, describing their quantitative and dynamic changes of expansion potential to chemotherapeutic agents have been received. Modeling of maximum tumor cells proliferative activity in vitro can be applied for development of test-system of individual cell sensitivity to chemotherapy in vivo.

[Modern methods of immunotherapy for metastatic melanoma].

Over the past five years drug therapy of disseminated melanoma took a giant step forward. In clinical practice there are several fundamentally new classes of drugs: inhibitors of the individual components of MAPK-signaling pathway and modulators of a work of immunological synapse (inhibitor of CTLA4 ipilimumab, inhibitors of PD1 nivolyumab and pem- brolizumab).Here are presented features of the mechanism of action of new immunotherapeutic agents, the review of results of their clinical use, the description of the main treatment- related adverse events. The interaction of new approaches with other methods of systemic treatment and an algorithm for per- sonalized use of these methods is regarded. Modern means of therapy allow achieving expressed and long effects giving pos- sibility in some cases to cure a patient. Rational sequential and combined use of different variants of systemic treatment for disseminated melanoma, appropriate diagnosis and treatment of treatment-related adverse events can significantly increase the length and quality of life of patients.

[Minimally invasive surgery with therapeutic effect in cancer patients].

During recent years ablative technologies have become very popular in tumor treatment. They are used in treatment for inoperable primary and metastatic tumors of the liver and the lung and also localized renal tumors of small sizes. The most studies on thermoablation in oncology are focused on the evaluation of tissue destruction and optimization of physical mechanisms, while potential mechanisms of immune response in thermoablation are still far from understanding. This study shows that with thermoablation of tumor within one month after the procedure the formation of a protective immune response is observed by increasing the content of activated T-helpers and cytotoxic T-lymphocytes.

[Assessment of the proliferative activity of tumor cells based on long-term phase-contrast microscopy CELL-IQ].

This work presents results of long-term phase-contrast microscopy research of proliferative potential of tumor cell lines utilizing live-cell imaging technology Cell-IQ (Chip-Man Technologies Ltd, Finland). It was found that the machine vision technology allowed to obtain sufficient body of evidence about high-quality and quantitative changes of proliferative activity of the tumor cells cultivated in static conditions. The present study demonstrates that modeling of time interval of maximum proliferative activity of tumors cells increases information efficacy and reliability of the analysis of dividing cell patterns using Cell-IQ technology. The models of exponential growth of various tumor cell lines, describing their quantitative and dynamic changes of expansion potential have been received. Modeling of maximum tumor cells proliferative activity can be applied for development of test-system of individual cell sensitivity to anticancer drugs in vitro.

[Heterogeneity of chromosomal abnormalities in cultured melanoma cells of human skin].

Karyotypes of 9 malignant melanoma patients has been described. It is ascertained that most often the damage is observed in chromosomes 1, 6, 7, 9 and 17, which is consistent with the data in the literature. Besides chromosomes 5 and 13 are also often involved in different rearrangements. Recurring aberrations are not discovered. Any correlation between survival and non-recurrent chromosomal aberrations is not discovered.

[Phase II clinical trial of autologous dendritic cell vaccine with immunologic adjuvant in cutaneous melanoma patients].

This paper describes the clinical results and immunologic changes in cutaneous melanoma patients receiving active specific immunotherapy with autologous dendritic cell vaccine (DCV) in combination with cyclophosphamide used as immunologic adjuvant. Twenty eight patients with morphologically verified stage III-IV cutaneous melanoma receiving therapy in N. N. Petrov Research Institute of Oncology between 2008 and 2011 were included in the study. All patients signed an informed consent form. Nineteen patients (67,9%) received DCV in therapeutic setting, 9 (32,1%) received it in adjuvant setting. DCV therapy was well tolerated. No serious adverse events were registered. Frequent adverse events included Grade 1-2 unspecific symptoms (fever, fatigue, flu-like symptoms) observed in 22% patients after 3,5% of vaccinations. In therapeutic settings the use DCV lead to clinical effect (PR+SD) in 36,6% of patients. PR was observed in 5% of (95% CI 0-15%) patients, SD in 31,6% (95% CI 13-56%). Duration of the objective responses was 168-965+days. Addition of immunologic adjuvant (cyclophosphamide 300 mg/m2 IV 2 hours) 3 days before vaccination increased its efficacy. In this patients group (n=12) the therapy lead to clinical benefit in 42% (95% CI 17-69%) of cases, median time to progression was 91 (95% CI 55-126) days. This regimen was selected for adjuvant therapy. In the adjuvant therapy group (n=9) the median time to progression was 112 (95% CI 58-166) days. Immunologic monitoring showed correlation ofT- and B-cell immune response with DCV clinical efficacy (p<0,05), no correlation with delayed hypersensivity reaction was observed (p>0,1). DCV is well tolerated and shows immunological and clinical response in stage III-IV skin melanoma patients.

[Laboratory evaluation of TGFbeta1, IL-10, VEGF levels in vivo and in vitro in patients with solid tumors].

Tumor cells can acquire the mechanisms of immune response evasion. One of these mechanisms is synthesis and secretion in the microenvironment of immunosuppressive factors able to block immune cells maturation and function. We investigated plasma levels of TGFbeta1 and IL0 in 10 healthy volunteers and 114 patients with solid tumors (breast cancer--24, gastrointestinal tumors--27, renal cell carcinoma--15, lung cancer--9, ovarian cancer--13, cutaneous melanoma--18, primary multiple tumors--2, prostate cancer--6). TGFbeta and IL10 concentration in supernatants of 37 primary cultures (cutaneous melanoma, renal cell carcinoma and prostate cancer) and 10 cultures of melanoma during cultivation were also studied. VEGF was determined by immunocytochemistry staining in 15 melanoma culture specimens. The lowest level of TGFbeta1 was documented in rectal cancer patients, 30.05 +/- 12.30 ng/ml (p < 0.05), the highest in renal cell cancer and pancreatic cancer patients, 145.61 +/- 11.32 and 146.15 +/- 30.56 ng/ml (p < 0.001), respectively. Primary cultures of tumor cells can synthesize traceable amounts of TGFbeta1 and IL10. Cultures of cutaneous melanoma, renal cell carcinoma and prostate cancer cells did not change expression level of IL-10 after several passages. VEGF was expressed in 20% of cutaneous melanoma cultures. We suppose that tests for TGFbeta1, IL10 and VEGF in culture supernatants from tumor cell lines, on the surface of the cells purposed for cancer vaccines and in serum of patients to be vaccinated are potentially useful.

[Immunochemical assay of MIC A production by tumor cells in vitro and in vivo as a component of antitumor vaccine development].

Due to immunological monitoring, most of aggressive tumor cells are selected capable of producing soluble factors of immunosuppression in their microenvironment. A ligand for NK- and T-cells receptor (MICA/B) activation is one of them. We investigated MICA concentrations in serum of 10 healthy volunteers and 114 patients with solid tumors (breast cancer - 24, gastrointestinal tumors - 27, renal cell carcinoma - 15, lung cancer - 9, ovarian carcinoma - 13, cutaneous melanoma - 18, primary multiple tumors - 2, prostate cancer - 6). The lowest level of MICA was reported in ovarian carcinoma (91.19 +/- 29.42 pg/ml), the highest - in rectal cancer (311.13 +/- 50.11 pg/ml) while mean concentration in healthy volunteers was (19.38 +/- 5.91 pg/ml). Cells of melanoma, renal cell carcinoma and prostate cancer became capable of producing MICA during cultivation and antitumor vaccine preparation. It is suggested that culture supernatants be tested for MICA contents as well as patients screened for vaccination. Selection of patients should be carried out on the basis of MICA molecules detection in blood flow.

[HLA-E molecule induction on the surface of tumor cells protects them from cytotoxic lymphocytes].

Modern immunotherapy has developed powerful tools for mounting antitumor response which nevertheless have had only limited success in clinic. Tumor cells use different mechanisms to escape from immune system. Thus, one of the reasons of unsuccessful immunotherapy might be induction of tolerance of tumor-specific cytotoxic lymphocytes by tumor cells. Previously we have demonstrated expression of HLA-E molecule by the cells of melanoma cell lines. In this paper we have studied HLA-E-dependent mechanism of melanoma cell escape from immune response.

[Expression of cytokeratins in tumors with perineural differentiation].

Twenty tumors with perineural differentiation (1 intraneural perineurioma, 10 conventional soft tissue perineuriomas, 3 reticular, 3 sclerosing, 1, atypical, and 2 malignant ones) were studied using a panel of antibodies directed against epithelial antigens. Seven (35%) cases were stained for CK14, 3 (15%) for AE1/AE3, and 2 (10%) for CAMS.2. These tumors showed focal expression of cytokeratins with labeling only a portion of cytoplasm. All tumors were negative for CEA, CK5/6, CK7, CK8, CK10, CK13, CK18, CK19, and CK20. The results of this investigation may be useful in the differential diagnosis of perineural tumors.

[An immunocytochemical investigation of antigen expression by skin melanoma cells cultured for vaccine production].

There is a great variety of histological patterns of skin melanoma and, in particular, that of its metastatic patterns. Malignant melanocytes are capable of influencing tumor-associated antigen expression. As of now, several varieties of melanoma-associated antigens (MAA) have been identified: MART1/melan A, tyrosinase, MITF, gp100, members of MAGE family, S100, CD63 and CD146. Peptides isolated from such molecules can induce MHC-restricted response of cytotoxic T-lymphocytes. It has been shown that level and nature of specific antigen expression caused by melanocytes correlate with tumor stage and a relationship between survival and MAA expression on tumor cells identified. Morphological features, growth pattern and proliferation rate varied in melanoma cell cultures used in our study. Our experiments involved evaluation of changes in the properties of antigens HLA (class 1 and 2), tumor tissue samples and cells isolated from them, which were capable of stable proliferative activity during passages 5, 10, 15, 20, 25, 30 and 35, and assay for MAA content. Levels of the antigens were significantly lower following long-term culturing melanoma cell melanoma cells in vitro. At initial passages (1-5), antigen profile in most cultures was similar to that in tumor tissue samples. Later on each cell population showed greater antigen expression heterogeneity matched by increased number of cells going through mitotic cycle; their nuclei were stained with antibodies to Ki-67. No HLF A/B/C molecule expression took place during tumor cell culturing: stained cells--in 68.9% of cultures (passages 1-5) and 36.3% (passage 35). However, HLA DQ/DP/DR molecule identification showed an inverse relationship: 44.1% (passage 5) while virtually all the cell lines did synthesize those molecules after passage 35. Hence, MAA and MHC (class 1 and 2) antigens expression in tumor cell should be monitored when they are used for preparation of autologuos and allogenic vaccines. In case of allogenic vaccine production, cell lines capable of stable production of MAA should be selected.

Phase I/II trial of gene therapy with autologous tumor cells modified with tag7/PGRP-S gene in patients with disseminated solid tumors: miscellaneous tumors.

BACKGROUND: The use of genetically modified autologous tumor cells appears to be a promising approach for cancer therapy. A phase I/II trial was undertaken to define the feasibility, safety and antitumor effects of the autologous vaccine prepared by transferring tag7/PGRP-S gene into malignant melanoma and renal cell carcinoma cells. PATIENTS AND METHODS: Twenty-one patients (17 with disseminated malignant melanoma and four with metastatic renal cell carcinoma) were enrolled in this study. Cytoreduction was performed in all cases prior to therapy. Autologous tumor cells were transfected with the tag7/PGRP-S gene, irradiated and injected intradermally every 3 weeks. RESULTS: Vaccinations were well tolerated by all patients, without clinically significant signs of toxicity. Delayed-type hypersensitivity was observed in 48% of cases. Antitumor immune response was observed in 95% of patients. There were no complete or partial responses; however, a minor response was achieved in one patient with renal cell carcinoma. The stabilization of neoplastic disease was observed in eight patients (seven with malignant melanoma and one with renal cell carcinoma). Median time to tumor progression was 3 months. CONCLUSIONS: The approach suggested here appears to be well tolerated and produces a number of durable clinical effects. Further studies are required to determine whether promising effects on immune activation will result in an actual clinical benefit for patients with malignant melanoma and renal cell carcinoma.

[Phase I-II trial of gene therapy with tag-7 modified autologous tumor cells in patients with metastatic solid tumors]. / I-II faza klinicheskoi otsenki éffektivnosti genoterapii na osnove autologichnykh opukholevykh kletok, modifitsirovannykh genom TAG7 u bol'nykh s disseminirovannymi solidnymi opukholiami.

A prospective (phase I-II) trial was undertaken to study the efficacy and toxicity of gene therapy with tag 70-modified autologous tumor cells in 32 patients with metastatic renal cell carcinoma (RC) (5) and melanoma (MBL) (27) treated at the Institute's Clinic (2001-2003). Resected material was reduced to cell culture, which was transfected with tag 70 gene and devitalized by irradiation. Immune blotting was used for gene expression. Clinical and immunological effectiveness was evaluated in 22 patients (MBL--17 and RC--5) who received 1-6 injections (3 on the average). Full course of vaccination was given to 8 (MBL--6 and RC--2). No complete or partial response was reported while least regression (50%) was registered in a case of RC metastatic to the lung. According to CT and ultrasound evidence, stabilization was achieved in 5 (23.8%) (MBL--4 and RC--1). Relapse-free period was 6.5+/-3.5 months beginning from the start of treatment. The vaccine was well tolerated while DHT reaction was observed in 47.6% (10 out of 17) of primary immunized patients. A trend of increased content of T- and B-cells in peripheral blood and intensified functional activity was established.