Postoperative autovaccinotherapy for patients with gastric cancer and expression of some proteins in tumor tissue

Aim: To study the efficacy of autovaccine in the treatment of gastric cancer and significance of molecular factors having prognostic values for disease outcome to evaluate its efficacy in clinical setting. Patients and Methods: 150 patients with histologically proven adenocarcinoma of the stomach of stages II, III or IV were enrolled into study. 86 patients have been treated with autovaccine (AV) after operation. Expression of p53, Bcl-2, receptors of tyrosine kinase, vascular endothelial growth factor (VEGF), Е-cadherin, α-catenin and β-catenin was determined in paraffin embedded tumor samples by means of immunohistochemical method with the use of respective monoclonal antibodies. Results: It was shown that application of AV has resulted in the increase of 3-year overall survival of patients having stage III of disease by more than 30%, but those having stage IV — only around 14%. The increase of 3-year overall survival of patients with metastases in lymph nodes (N1–2) was observed also in more than 30%. It has been suggested the optimal phenotype for vaccine application: р53(+), EGFR(+), HER-2 neu (+), β-catenin (+), VEGF(+) and Bcl-2(+) with no dependence on E-cadherin and α-catenin presence. Conclusion: It was determined that the best effect of AV application is observed in patients with category Т3–4, poorly-differentiated tumors, metastases in lymph nodes (N1–2), but without distant metastases (М0). Gastric cancer patients with p53, EGFR, HER-2/neu, β-catenin, VEGF and Bcl-2-positive tumors are the favorable group for the treatment with AV in the adjuvant regime

Elevation of efficacy of cancer vaccine combined with interferon and inducer of endogeneous interferon synthesis amixin

Aim: To study in vivo efficacy of combined administration of cancer vaccine (CV), interferon (IFN) and inducer of endogenous IFN — amixin. Materials and Methods: Sarcoma-37 cells were transplanted to female Balb/c mice. For the treatment, CV prepared from sarcoma-37 cells with the use of cytotoxic lectines from B. subtilis B-7025, murine IFN and amixin or their combinations were used. IFN production, content of circulating immune complexes and level of specific IgG antibodies in blood serum were determined by standard immunologic methods. Results: Using solid form of sarcoma-37 it has been shown that introduction of IFN and amixin significantly elevated efficacy of vaccine therapy, in particular index of tumor growth inhibition reach 89.2% and 81.7%. Upon combined use of CV and IFN or CV and amixin (25 mg/kg) respectively. Significant prolongation of average life span of the animals treated with CV and IFN or CV and amixin (25 mg/kg) has been registered (up to 92.7 ± 10.4 and 95.0 ± 6.2 days respectively, vs 46.8 ± 1.5 days for control animals). Conclusion: Obtained results have shown expediency of the development of schemes for combined introduction of CV with exogenous IFN, and with inducer of endogenous IFN (amixin) for elevation of efficacy of vaccine therapy.Цель: изучить в эксперименте эффективность комбинированной схемы введения противоопухолевой вакцины (CV) с интерфероном (ИФН) и индуктором эндогенного ИФН — амиксином. Материалы и методы: саркому-37 трансплантировали мышам-самкам Balb/c. Для лечения использовали CV, приготовленную из клеток саркомы-37 с помощью цитотоксических лектинов B. subtilis B-7025, мышиный ИФН (1000 ед.) и амиксин (10 и 25 мг/кг). Иммунологические исследования включали определение в сыворотке крови титров ИФН, количества циркулирующих иммунных комплексов и уровня специфических противоопухолевых IgG-антител. Результаты: на модели солидной формы саркомы-37 показано, что применение ИФН и амиксина достоверно способствует повышению результатов вакцинотерапии, а именно, при комбинированном использовании CV и ИФН индекс торможения опухолевого роста (ИТО) достигал 89,2%; при сочетании CV и амиксина (25 мг/кг) ИТО составил 81,7%. Зарегистрировано существенное увеличение средней продолжительности жизни животных, получивших CV с ИФН или амиксином (25 мг/кг), до 92,7 ± 10,4 и 95,0 ± 6,2 сут соответственно, по сравнению с такой контрольных мышей (46,8 ± 1,5 сут, p < 0,05). Выводы: полученные результаты свидетельствуют о перспективности разработки комбинированных схем введения CV как с препаратом экзогенного ИФН, так и с индуктором эндогенного ИФН (амиксин), что позволяет повысить эффективность вакцинотерапии

Antitumor and antimetastatic activities of vaccine prepared from cisplatin-resistant lewis lung carcinoma

To study antitumor and antimetastatic activities of antitumor vaccine (ATV) prepared from cisplatin (CP) sensitive and resistant strains of Lewis lung carcinoma (LLC). Methods: The inhibition of tumor growth, and the mean survival time of the tumor-bearing animals, the number and the volume of metastases were measured as the indices of ATV efficacy. The activity of cytotoxic T-lymphocytes and natural killer cells, peritoneal macrophages (Mph), the level of tumor necrosis factor and the total proteolytic activity of blood plasma (PA) were assessed. Results: ATV from CP resistant LLC prepared using cytolectin (CL) of В. subtilis В-7025 significantly inhibited growth of CP resistant tumors (by 52%) and increased mean survival time (MST) of animals (by 44.6%). The index of metastasis inhibition for ATV prepared from CP sensitive or resistant LLC was 154.5% and 227.0%, respectively. In all vaccine-treated animals, Mph activity was shown to be significantly increased. In spite of high antitumor and antimetastatic effects of ATV prepared from CP resistant LLC, PA in plasma of animals inoculated with CP resistant LLC was increased significantly upon vaccine administration

Experimental study of the efficacy of combined use of cancer vaccine and interferon

Aim: To study in in vivo model the efficacy of combined scheme of administration of cancer vaccine (CV) and interferon (IFN). Materials and Methods: Lewis lung carcinoma (LLC) was transplanted to male C57Bl mice. For treatment, CV prepared from LLC cells with the use of cytotoxic lectins of B. subtilis B-7025, and preparation of murine IFN-alpha were used. Therapeutic effect was evaluated by measurement of tumor volume and analysis of average life span (ALS) of treated animals. Immunologic study included determination of antitumor cytotoxicity of T-lymphocytes (CTL) and natural killer (NK) cells by radiometric method, functional activity of peritoneal macrophages (MP) — by colorimetric test with nitroazole blue, and evaluation of titers of tumor necrosis factor (TNF) and interleukins-1 and -2 (IL-1, 2). Results: It has been shown that the use of IFN preparation significantly elevated efficacy of vaccine therapy of solid form of LLC: duration of latent period of tumor growth elevated by 25%, ALS — by 28%, index of tumor growth inhibition — by 35–40%. Upon combined use of CV and IFN, significant activation of the cells — effectors of nonspecific immune defense (MP), and specific one (CTL) was observed. Conclusion: The obtained results evidence on perspectiveness of the development of combined schemes of administration of CV and IFN for elevation of the efficacy of vaccine therapy.Цель: исследовать в эксперименте эффективность комбинированной схемы введения противоопухолевой вакцины (ПВ) и интерферона (ИФН). Материалы и методы: карциному легкого Льюис (КЛЛ) трансплантировали мышам-самцам C57Bl. Для лечения использовали ПВ, приготовленную из клеток КЛЛ с помощью цитотоксических лектинов B. subtilis B-7025, и препарат мышиного ИФН. Терапевтический эффект оценивали путем измерения объема солидной опухоли и анализа средней продолжительности жизни опытных животных. Иммунологическое исследование включало определение противоопухолевой цитотоксичности Т-лимфоцитов (ЦТЛ) и природных киллерных клеток (ПКК) радиометрическим методом; функциональной активности перитонеальных макрофагов (Мф) в колориметрическом НСТ-тесте; определение титров фактора некроза опухоли (ФНО), интерлейкинов-1 и -2. Результаты: показано, что использование препарата ИФН существенно повышает эффективность вакцинотерапии солидной формы модельной КЛЛ: на 25% повышается продолжительность латентного периода, на 28% — средняя продолжительность жизни мышей, на 35–40% — индекс торможения опухолевого роста. При комбинированном применении ПВ и ИФН отмечают существенную активацию клеток-эффекторов как неспецифической (Мф), так и специфической (ЦТЛ) иммунной защиты. Выводы: полученные результаты свидетельствуют о перспективности разработки комбинированных схем введения ПВ с ИФН, позволяющих повысить эффективность вакцинотерапии

Use of xenogeneic vaccine modified with embryonal nervous tissue antigens in the treatment of B16‑melanoma-bearing mice

The aim of the work was experimental study of anticancer efficacy of xenogeneic cancer vaccine (XCV) developed on the basis of rat embryonic nervous tissue and protein-containing metabolite of Bacillus subtilis В-7015 (70 kDa), in В-16 melanoma-bearing С57Bl/6 mice. Methods: Immunological methods and methods of experimental oncology were used. Effects of XCV on primary and secondary organs of immune system of experimental animals, its anticancer and antimetastatic efficacy were evaluated. Results: It has been shown that XCV did not induced toxic effects on organism, and did not caused inflammatory reactions. The relation between the degree of XCV anticancer efficacy with the regimen of its use and the presence of primary tumor has been analyzed. It has been demonstrated that the developed XCV possesses significant antimetastatic activity if it is used after surgical removal of the primary tumor: in this case lung metastasis inhibition index reached 97.4%. Conclusion: High immunogenecity of new XCV creates perspectives for detailed study of its mechanisms of action. Key Words: oncofetal antigens, xenogeneic cancer vaccine, В-16 melanoma, immunotoxicity, effectors of anticancer defence

Cytotoxic activity of immune cells following administration of xenogeneic cancer vaccine in mice with melanoma B-16

Aim: To study the effects of xenogeneic cancer vaccine (XCV) developed on the basis of nervous tissue antigen from rat embryo of late gestation period and protein-containing metabolite of Bacillus subtilis with molecular weight of 70 kDa, on specific and unspecific antitumor reactions of cellular and humoral chains of immune system, and to analyze possible mechanisms of its antimetastatic action. Materials and Methods: XCV was administered triply with 3-day intervals after surgical removal of experimental melanoma В-16 in C57Bl/6 mice. Cytotoxic activity (CTA) of splenocytes against target cells К-562 as well as CTA of splenocytes, peritoneal macrophages (PM) and blood serum against melanoma В-16 target cells were determined using МТТ test. The content of circulating immune complexes (CIC) in blood serum was evaluated by precipitation reaction. Results: Immunologic effects of XCV vaccination in experimental animals with surgically removed melanoma B-16 in comparison with similarly treated unvaccinated mice were as follows: prevention of medium molecular weight CIC accumulation in blood serum during all observation period, significant increase (р < 0.05) of CTA of effectors of unspecific antitumor immunity (natural killer cells — NK — by 25.5 ± 1.7 vs 12.5 ± 5.4%, and PM — by 37.3 ± 0.6 vs 32.0 ± 0.9%, respectively) at 37th day after the surgery, and also preservation of functional activity of specific cytotoxic lymphocytes at the level of intact control. Conclusion: The results of the study allow propose that antimetastatic effect of XCV vaccination could be based on increased CTA of NK and PM, and preservation of CTL functional activity at late terms after surgical removal of B-16 primary tumors. Key Words: xenogeneic cancer vaccine, melanoma В-16, natural killer cells, macrophages, cytotoxic lymphocytes, cytotoxic activity, antimetastatic activity

CYTOTOXIC ACTIVITY OF IMMUNE CELLS FOLLOWING ADMINISTRATION OF XENOGENEIC CANCER VACCINE IN MICE WITH MELANOMA B-16

Aim: To study the effects of xenogeneic cancer vaccine (XCV) developed on the basis of nervous tissue antigen from rat embryo of late gestation period and protein-containing metabolite of Bacillus subtilis with molecular weight of 70 kDa, on specific and unspecific antitumor reactions of cellular and humoral chains of immune system, and to analyze possible mechanisms of its antimetastatic action. Materials and Methods: XCV was administered triply with 3-day intervals after surgical removal of experimental melanoma В-16 in C57Bl/6 mice. Cytotoxic activity (CTA) of splenocytes against target cells К-562 as well as CTA of splenocytes, peritoneal macrophages (PM) and blood serum against melanoma В-16 target cells were determined using МТТ test. The content of circulating immune complexes (CIC) in blood serum was evaluated by precipitation reaction. Results: Immunologic effects of XCV vaccination in experimental animals with surgically removed melanoma B-16 in comparison with similarly treated unvaccinated mice were as follows: prevention of medium molecular weight CIC accumulation in blood serum during all observation period, significant increase (р < 0.05) of CTA of effectors of unspecific antitumor immunity (natural killer cells — NK — by 25.5 ± 1.7 vs 12.5 ± 5.4%, and PM — by 37.3 ± 0.6 vs 32.0 ± 0.9%, respectively) at 37th day after the surgery, and also preservation of functional activity of specific cytotoxic lymphocytes at the level of intact control. Conclusion: The results of the study allow propose that antimetastatic effect of XCV vaccination could be based on increased CTA of NK and PM, and preservation of CTL functional activity at late terms after surgical removal of B-16 primary tumors. Key Words: xenogeneic cancer vaccine, melanoma В-16, natural killer cells, macrophages, cytotoxic lymphocytes, cytotoxic activity, antimetastatic activity