Studies of immunotherapy: the experience of using dendritic vaccines in the treatment of patients with cancer

Introduction. Personalized medicine is a revolutionary approach to treatment based on the fact that genetic characteristics, physiological processes, environmental influences and lifestyle form an individual profile that must be taken into account when developing a treatment strategy. This is especially true in diseases with a complex pathogenesis and low effectiveness of standard treatment methods, for example, in gliomas with a high degree of malignancy. Gliomas, which occupy up to 46 % of all tumors of the CNS, pose a serious problem for oncology. Even with the use of combination therapy, including surgery, radiation and chemotherapy, the five-year survival rate of patients remains extremely low, and does not exceed 10 %. This tragic statistic pushes researchers to search for new, more effective treatments. Aim. To substantiate the expediency of using cellular immunotherapy, as well as allogeneic (donor) immunocompetent cells injected directly into the cerebrospinal fluid in patients with recurrent gliomas. Materials and methods. A group of five patients aged 2 to 16 years was formed: three were diagnosed with anaplastic astrocytoma (AA), one of the most common forms of gliomas. One patient suffered from glioblastoma multiforme (MG), the most aggressive and fastest-growing form of glioma, and he had a third recurrence of the disease, indicating a high degree of tumor resistance to previous treatments. The fifth patient was diagnosed with diffuse glioma (DG) of the brain stem, the localization of which excluded surgical intervention. The average time to the first relapse in patients was 12 months (4–16 months), to the second — 5 months (1–8 months). This illustrates the rapid progression of the disease and the critical need for new treatment strategies. The immunotherapy protocol used in the study consisted of two main components. First, patients were given an autologous vaccine based on dendritic cells (DV), specialized cells of the immune system capable of “presenting” tumor antigens to T lymphocytes, activating the immune response against malignant cells. The use of autologous dendritic cells minimizes the risk of rejection and side effects. Secondly, intrathecal/intraventricular injections of allogeneic immunocompetent cells were an important component of therapy. This is a key point of the study, since the introduction of donor cells directly into the central nervous system allows for a high concentration of immune cells in the tumor area, enhancing the antitumor effect. Results. Two out of three AA patients achieved a significant interval without disease progression — 67 and 71 months, respectively. These data indicate a potentially high efficacy of the combined immunotherapy used. Moreover, a patient with a third MG relapse who has exhausted standard treatment options is alive without additional therapy after 15 years. Conclusion. Since the data are based on a small number of patients, further studies are needed to confirm the efficacy and safety of this method. Further research should focus on optimizing the treatment protocol, identifying the most effective cell combinations, and increasing the patient sample to obtain more reliable statistical data.