Background . Most patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors achieve durable optimal responses. Loss of the achieved molecular response is observed in 15–30 % of patients. Mutations in the BCR::ABL kinase domain are one of the most common mechanisms for the development of resistance to tyrosine kinase inhibitors. Aim . To conduct a retrospective analysis of the BCR::ABL kinase domain mutational profile in patients with CML observed at the Russian Research Institute of Hematology and Transfusiology from 2012 to 2023. To assess the impact of mutations type and number on the rate of achieving a major molecular response (MMR). To study the risk of MMR loss depending on the therapy line and existing mutational status. Materials and methods . 1831 patients with CML were examined at different times. The mutational status of the BCR::ABL kinase domain was analyzed by direct Sanger sequencing. A standard cytogenetic study was carried out using GTG banding technology with the analysis of at least 20 metaphase plates. Results . Mutations in the BCR::ABL kinase domain were identified in 27.6 % of the total studied patients. The most common mutation, 6.3 % in the overall group or 22.7 % among patients with mutations, was the T315I mutation. Additional chromosomal aberrations (ACAs) were detected in Ph-positive cells in 20.5 % of patients, in Ph-negative clones in 3.9 % of cases (p = 0.0001). The frequency of ACAs detection did not statistically significantly differ (p = 0.25) between patients with BCR::ABL mutations (23.5 %) and with a negative mutation status (17.7 %), and the presence of mutations in the kinase domain did not correlate with ACAs in Ph-positive clones (p = 0.73). However, the frequency of T315I mutation detection in Ph-positive cells had significant differences: 40.9 % in combination with ACAs and 21 % without ACAs (p = 0.032). Patients with the T315I mutation had significantly worse MMR than patients with mutations in other BCR::ABL regions (p = 0.04) and patients without mutations (p = 0.02). The probability of MMR achieving did not differ significantly between patients with different numbers of BCR::ABL mutations (p = 0.14). Loss of MMR occurred more often in patients with mutations (p = 0.04) and not depend on the line of therapy (p = 0.03). Conclusion . For complete monitoring and optimal choice of therapy, CML patients require not only monitoring of BCR::ABL relative expression level, but also standard cytogenetic and analysis of the mutational status.

Множественная миелома остается сложным гематологическим заболеванием, требующим постоянного изучения его биологии и поиска новых терапевтических подходов. Несмотря на внедрение в клиническую практику различных классов лекарственных средств, таких как иммуномодулирующие препараты, ингибиторы протеасом и моноклональные антитела, множественная миелома по-прежнему включена в группу хронических неизлечимых заболеваний. Цель настоящей работы – предоставить всесторонний обзор патогенетических механизмов, лежащих в основе лекарственной резистентности, и рассмотреть возможные опции персонализированной терапии. Путем подробного анализа данных клинических исследований последних лет оценить эффективность и возможность применения в клинической практике развивающихся методов лечения. Multiple myeloma (MM) remains a complex hematological disease that requires constant study of its biology and the search for new therapeutic approaches. Despite the introduction into clinical practice of various classes of drugs, such as immunomodulatory drugs, proteasome inhibitors and monoclonal antibodies, MM is still included in the group of chronic incurable diseases. The purpose of this work is to provide a comprehensive overview of the pathogenetic mechanisms underlying drug resistance and to consider possible options for personalized therapy. Through a detailed analysis of data from clinical trials in recent years, to evaluate the effectiveness and feasibility of developing treatment methods in clinical practice.

Background. Most patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors achieve durable optimal responses. Loss of the achieved molecular response is observed in 15–30 % of patients. Mutations in the BCR::ABL kinase domain are one of the most common mechanisms for the development of resistance to tyrosine kinase inhibitors.Aim. To conduct a retrospective analysis of the BCR::ABL kinase domain mutational profile in patients with CML observed at the Russian Research Institute of Hematology and Transfusiology from 2012 to 2023. To assess the impact of mutations type and number on the rate of achieving a major molecular response (MMR). To study the risk of MMR loss depending on the therapy line and existing mutational status.Materials and methods. 1831 patients with CML were examined at different times. The mutational status of the BCR::ABL kinase domain was analyzed by direct Sanger sequencing. A standard cytogenetic study was carried out using GTG banding technology with the analysis of at least 20 metaphase plates.Results. Mutations in the BCR::ABL kinase domain were identified in 27.6 % of the total studied patients. The most common mutation, 6.3 % in the overall group or 22.7 % among patients with mutations, was the T315I mutation. Additional chromosomal aberrations (ACAs) were detected in Ph-positive cells in 20.5 % of patients, in Ph-negative clones in 3.9 % of cases (p = 0.0001). The frequency of ACAs detection did not statistically significantly differ (p = 0.25) between patients with BCR::ABL mutations (23.5 %) and with a negative mutation status (17.7 %), and the presence of mutations in the kinase domain did not correlate with ACAs in Ph-positive clones (p = 0.73). However, the frequency of T315I mutation detection in Ph-positive cells had significant differences: 40.9 % in combination with ACAs and 21 % without ACAs (p = 0.032). Patients with the T315I mutation had significantly worse MMR than patients with mutations in other BCR::ABL regions (p = 0.04) and patients without mutations (p = 0.02). The probability of MMR achieving did not differ significantly between patients with different numbers of BCR::ABL mutations (p = 0.14). Loss of MMR occurred more often in patients with mutations (p = 0.04) and not depend on the line of therapy (p = 0.03).Conclusion. For complete monitoring and optimal choice of therapy, CML patients require not only monitoring of BCR::ABL relative expression level, but also standard cytogenetic and analysis of the mutational status.

Background. Most patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors achieve durable optimal responses. Loss of the achieved molecular response is observed in 15–30 % of patients. Mutations in the BCR::ABL kinase domain are one of the most common mechanisms for the development of resistance to tyrosine kinase inhibitors.Aim. To conduct a retrospective analysis of the BCR::ABL kinase domain mutational profile in patients with CML observed at the Russian Research Institute of Hematology and Transfusiology from 2012 to 2023. To assess the impact of mutations type and number on the rate of achieving a major molecular response (MMR). To study the risk of MMR loss depending on the therapy line and existing mutational status.Materials and methods. 1831 patients with CML were examined at different times. The mutational status of the BCR::ABL kinase domain was analyzed by direct Sanger sequencing. A standard cytogenetic study was carried out using GTG banding technology with the analysis of at least 20 metaphase plates.Results. Mutations in the BCR::ABL kinase domain were identified in 27.6 % of the total studied patients. The most common mutation, 6.3 % in the overall group or 22.7 % among patients with mutations, was the T315I mutation. Additional chromosomal aberrations (ACAs) were detected in Ph-positive cells in 20.5 % of patients, in Ph-negative clones in 3.9 % of cases (p = 0.0001). The frequency of ACAs detection did not statistically significantly differ (p = 0.25) between patients with BCR::ABL mutations (23.5 %) and with a negative mutation status (17.7 %), and the presence of mutations in the kinase domain did not correlate with ACAs in Ph-positive clones (p = 0.73). However, the frequency of T315I mutation detection in Ph-positive cells had significant differences: 40.9 % in combination with ACAs and 21 % without ACAs (p = 0.032). Patients with the T315I mutation had significantly worse MMR than patients with mutations in other BCR::ABL regions (p = 0.04) and patients without mutations (p = 0.02). The probability of MMR achieving did not differ significantly between patients with different numbers of BCR::ABL mutations (p = 0.14). Loss of MMR occurred more often in patients with mutations (p = 0.04) and not depend on the line of therapy (p = 0.03).Conclusion. For complete monitoring and optimal choice of therapy, CML patients require not only monitoring of BCR::ABL relative expression level, but also standard cytogenetic and analysis of the mutational status.

Mantle cell lymphoma (MCL) is a type of peripheral B-cell non-Hodgkin’s lymphoma characterized by constitutive cyclin D1 overexpression leading to cell-cycle dysregulation and disruption of DNA damage repair. Apart from the typical translocation t(11;14)(q13;q32) and more rare variants, such as t(2;11)(p11;q13) and t(11;22)(q13;q11), a considerable number of patients quite often show secondary molecular and chromosomal aberrations underlying heterogeneity of the clinical course of MCL. Among a wide range of molecular genetic abnormalities, particular attention during the last years has been concentrated on studying the so-called double-hit MCL within a subgroup of patients with translocations involving CCND1 and MYC genes. Double-hit MCL is distinguished with rapid progression and tumor generalization at the time of diagnosis. Poor prognosis and low survival rates in most MCL patients call for the fastest possible diagnosis. Morphological and immunohistochemical as well as genetic methods (standard cytogenetic technique and fluorescence in situ hybridization) contribute to improving the quality of evidence-based diagnosis. The results of comprehensive diagnostic studies optimize prognosis assessment and treatment decision making in clinic.

Annexins as Ca 2+ /phospholipid-binding proteins are involved in the control of many biological processes essential for plant growth and development. In a previous study, we had shown, using a proteomic approach, that the synthesis of two annexins is induced in pea roots in response to rhizobial inoculation. In this study, phylogenetic analysis identified these annexins as PsAnn4 and PsAnn8 based on their homology with annexins from other legumes. The modeling approach allowed us to estimate the structural features of these annexins that might influence their functional activity. To verify the functions of these annexins, we performed comparative proteomic analysis, experiments with calcium influx inhibitors, and localization of labeled proteins. Essential down-regulation of PsAnn4 synthesis in a non-nodulating pea mutant P56 ( sym10 ) suggests an involvement of this annexin in the rhizobial symbiosis. Quantitative RT-PCR analysis showed that PsAnn4 was upregulated at the early stages of symbiosis development, starting from 1–3 days after inoculation to up to 5 days after inoculation, while experiments with the Ca 2+ channel blocker LaCl 3 revealed its negative influence on this expression. To follow the PsAnn4 protein localization in plant cells, it was fused to the fluorophores such as red fluorescent protein (RFP) and yellow fluorescent protein (YFP) and expressed under the transcriptional regulation of the 35S promoter in Nicotiana benthamiana leaves by infiltration with Agrobacterium tumefaciens . The localization of PsAnn4 in the cell wall or plasma membrane of plant cells may indicate its participation in membrane modification or ion transport. Our results suggest that PsAnn4 may play an important role during the early stages of pea-rhizobial symbiosis development.

In this work, we analyzed the localization and effect of suppression of gene expression of β-subunits of G-proteins on nodule formation. The possible interaction of α- and β-subunits with a set of signal regulators in vitro was revealed.