Exosomes are small vesicles which are produced by the cells and released into the surrounding space. They can transfer biomolecules into recipient cells. The main goal of the work was to study the exosome involvement in the cell transfer of hormonal resistance. The experiments were performed on in vitro cultured estrogen-dependent MCF-7 breast cancer cells and MCF-7 sublines resistant to SERM tamoxifen and/or biguanide metformin, which exerts its anti-proliferative effect, at least in a part, via the suppression of estrogen machinery. The exosomes were purified by differential ultracentrifugation, cell response to tamoxifen was determined by MTT test, and the level and activity of signaling proteins were determined by Western blot and reporter analysis. We found that the treatment of the parent MCF-7 cells with exosomes from the resistant cells within 14 days lead to the partial resistance of the MCF-7 cells to antiestrogen drugs. The primary resistant cells and the cells with the exosome-induced resistance were characterized with these common features: decrease in ERα activity and parallel activation of Akt and AP-1, NF-κB, and SNAIL1 transcriptional factors. In general, we evaluate the established results as the evidence of the possible exosome involvement in the transferring of the hormone/metformin resistance in breast cancer cells.

Одним из потенциальных биомаркеров для больных метастатическим гормоночувствительным раком предстательной железы (РПЖ) может быть определение экспрессии лиганда белка программируемой клеточной гибели (PD-L1) в опухоли, ассоциированной с неблагоприятными результатами лечения и снижением выживаемости больных раком поджелудочной железы, легкого и другими злокачественными новообразованиями. Цель исследования -оценка прогностической значимости положительного статуса PD-L1(+) опухоли на время до развития кастрационной резистентности (КРРПЖ) у больных метастатическим РПЖ, получающих гормональную андрогендепривационную терапию в 1-й линии системного противоопухолевого лечения.

No abstract

Malignant pleural mesothelioma is associated with poor prognosis and resistance to chemotherapy. This gives reason to search for as well new effective methods of treatment as predictive factors. Programmed cell death receptor PD-1 and its ligands PD-L1 and PD-L2 are the representatives of the system of the «immunologic checkpoint» whose main function is the regulation and modulation of immune response, the decrease of the immune cell damage in organs and tissues and also prevention running of an autoimmune process. Tumor cells are able to use a PD-1/PD-L1-signaling pathway to evade the immune system. The assessment of the level of expression of PD-L1 is regarded as a prognostic marker of the life expectancy, but also as a predictor of response to anti-PD-1/PD-L1 immunotherapy.

Bronchopulmonary neuroendocrine tumors (NETs) refer to malignant epithelial neoplasms of neuroendocrine origin, which form highly heterogeneous group with respect to biological behavior and clinical manifestations. Three main categories of different grades of malignancy are distinguished in the diagnosis of lung NETs: typical carcinoids (TK), atypical carcinoids (AK) and the most aggressive low-differentiated tumors including small-cell and large-cell neuroendocrine lung carcinomas. These groups differ in terms of disease prognosis and therapeutic approaches, but the criteria currently used do not always allow clear boundaries between different histological variants. The search for additional diagnostic parameters and individual prognosis markers is currently actual for the grading and optimal classification of NETs. For the first time we studied the expression of Retinoic Acid Binding Protein-1 (CRABP1) in different variants of lung NETs. IHC analysis of 43 samples of lung NETs with various degrees of differentiation and grades revealed the statistically significant correlation between nuclear localization of CRABP1 and proliferation index «Ki-67» and tumor grade. The results pointed on the involvement of CRABP1 in the pathogenesis of lung NETs and indicated the need for further investigation of the relationship of the nuclear CRABP1 with clinical parameters and patient survival to determine whether this protein can be used as a marker for differential diagnosis and/or disease prognosis.