Bone marrow (BM) and subcutaneous adipose tissue (Ad) are both considered being prospective sources of MSC for therapeutic applications. However, functional properties and therapeutic efficacy of MSC derived from different tissues of the same patient are still poorly investigated. In our study, BM-MSC and F-MSC cultures from 43 adult donors were evaluated in successive passages for immunophenotype, secretion of VEGF, SDF1, MCP1, IL6 and TGFβ1, frequency of colony-forming units (CFU-F), frequency of adipo- and osteo-progenitors (CFU-Ad, CFU-Ost), and for onset of in vitro replicative senescence. We have demonstrated that at early passages (P2-P4 or up to 14-15 in vitro population doublings) BM- and Ad- derived MSC cultures are comparable in such important characteristics as proliferation rate (population doubling time: 3,4±0,2% in BM-MSC, 3±0,3 % in F-MSC), clonogenity (CFU-F frequency: 32±5% in BM-MSC, 31±5% in F-MSC), differentiation potential (CFU-Ad frequency: 10,4±2% in BM-MSC, 13±3% in F-MSC; CFU-Ost frequency: 18,5±5,5% in BM-MSC, 18±5% in F-MSC), but differ significantly in abundance of CD146+ fraction within the sample (25±5% in BM-MSC, 7±3 % in F-MSC) and in a level of VEGF, SDF-1, MCP1 and TGFβ1 secretion. We have also demonstrated that BM-MSC enter senescence after P3-4 while most of F-MSC did not show senescence features up to P6-8. Together, these data demonstrate that specific properties of MSC from different sources should be always taken into account, when developing and optimizing the specific protocols for MSC expansion and evaluation for each particular clinical application.

In children with cancer, the issues related to the quality of life are becoming increasingly important together with the improvement of survival rates. This creates an entirely new challenge – minimizing the toxicity of the antitumor therapy without reducing its effectiveness. One of the specific side effects of the antitumor therapy is gonadotoxicity, which negatively affects both the somatic and mental state of the survivors. Since ovarian stimulation is ineffective in prepubertal patients, ovarian tissue cryopreservation (OTC) remains the most promising option to preserve fertility. The primary goal of this publication is to emphasize the importance of the reproductive health problem in girls with oncological diseases, with a description of the current data of international literature on the prospects of OTC in order to preserve fertility. Another goal is to present a multidisciplinary strategy for the management of prepubertal age patients with the oncological disease within the framework of the Oncological Fertility Project at Almazov National Medical Research Center. Based on the data of Russian and international literature, as well as existing guidelines and recommendations on reproductive health, a single algorithm for selecting patients has been developed, considering the expected gonadal toxicity for the use of the OTC in prepubertal girls. The developed algorithm allows identifying patients of prepubertal age, requiring the use of new possibilities of reproductive technologies. In a long-term date, we are planning to evaluate the effectiveness of the orthotopic reimplantation technique of the cryopreserved ovarian tissue in restoring the reproductive function. A multidisciplinary team of specialists and the possibilities of the Federal Center facilitate implementing the Oncofertility Program in routine practice for girls and young women, receiving gonadotoxic treatment.

Background: Myeloid sarcoma (MS) is a very rare condition, develops both in patients with other hematological neoplasms, and as isolated tumor. MS of the gynecologic tract is extremely rare. An available literature data about diagnosis and management of MS is summarized in the article. The role of chemotherapy, radiation therapy, surgery and bone marrow transplantation in the treatment is discussed. Polychemotherapy and allogeneic bone marrow transplantation were suggested to be the optimal treatment strategy of MS of the gynecological tract. The use of new targeted agents results in promising clinical data. Case presentation: We are presenting a rare clinical case of a MS of the uterine cervix with concomitant bone marrow involvement and describe all the peculiarities of the clinical course, diagnosis, and treatment. The patient received chemotherapy followed by allogeneic bone marrow transplantation. The pre-transplant therapy allowed us to perform allogeneic bone marrow transplantation with the deepest response possible: complete PET-negative and MRD-negative remission of the disease. Conclusions: MS remains a subject of discussion regarding its diagnostic and therapeutic aspects. The use of novel targeting agents can be perspective option for patient with extramedullary disease.

Mutations in the FLT3 gene not only lead to abnormalities in its structure and function, but also affect the expression of other genes involved in leukemogenesis. This study evaluated the expression of genes that are more characteristic of neuroblastoma but less studied in leukemia. N-MYC oncogene expression was found to be more than 3-fold higher in primary AML patients carrying the FLT3-ITD mutation compared to carriers of other mutations as well as patients with normal karyotype (p = 0.03946). In contrast to the expression of several genes (C-MYC, SPT16, AURKA, AURKB) directly correlated to the allelic load of FLT3-ITD, the expression of the N-MYC oncogene is extremely weakly related or independent of it (p = 0.0405). Monitoring of N-MYC expression in some patients with high FLT3-ITD allelic load receiving therapy showed that a decrease in FLT3-ITD allelic load is not always accompanied by a decrease in N-MYC expression. On the contrary, N-MYC expression may remain elevated during the first three months after therapy, which is additional evidence of the emergence of resistance to therapy and progression of AML.

Background. The most promising variant of adoptive immunotherapy of the B-line oncohematological diseases includes the use of cells with the chimeric antigen receptor (CAR T-cells), that showed extraordinary results in clinical studies. Aim. To manufacture CAR T-cells for the clinical use and to study their cytotoxicity in vitro. Methods. Human T-lymphocytes were transduced by the lentiviral vector containing anti-CD19-CAR, RIAD, and GFP genes. The T-cell transduction efficacy was assessed on the basis of GFP protein signal by flow cytometry. Propidium iodide was used to analyse the cell viability. Cytotoxic activity of the manufactured CAR T-cells was studied in the presence of the target cells being directly co-cultivated. Analysis of the number and viability of CAR T-cells and cytokine expression was performed by flow cytometry. Results. The viability of the transduced T-cells and GFP expression reached 91.87 % and 50.87 % respectively. When cultured in the presence of IL-2 and recombinant CD19 (the target antigen), the amount of CAR-T after 120 h of the process was 1.4 times larger compared with the period of 48 h. In the cytotoxic test of co-cultivation CAR-T with the K562-CD19+ cells the percentage of CAR-T increased to 57 % and 84.5 % after 48 h and 120 h of exposure respectively. When cultured with the K562 cells (test line not expressing CD19) the number of CAR T-cells decreased to 36.2 % within 48 h while the number of K562 cells increased to 58.3 %. The viability of target cells in the experimental and control groups was 3.5 % and 36.74 % respectively. Comparison of IL-6 level in the control and experimental groups revealed that the differences are insignificant, as opposed to the level of other cytokines (IFN-γ, IL-2, TNF) which proved to be different in both groups. Conclusion. The present work resulted in the production of anti-CD19 CAR T-cells with adequate viability. The in vitro model demonstrated their cytotoxicity. Manufacturing of CAR T-cells for clinical use is the first step of the development of adoptive immunotherapy in the Russian Federation.

Objectives: To the best of our knowledge, data from Gemtuzumab ozogamicin in Acute Myeloid Leukemia (AML) patients with failure of organ functions and poor performance status are extremely lacking. Moreover, the fast recovery from organ failure, after Gemtuzumab ozogamicin administration, has never been reported. This study aimed to demonstrate the efficacy and rapid response of Gemtuzumab ozogamicin in refractory acute myeloid leukemia (AML) patients with pulmonary and kidney failure and poor performance status. Three refractory AML patients, with organ dysfunction, are described. One patient was pre-treated with intensive chemotherapy, and two other patients progressed during Azacitidine treatment. Two patients had respiratory failure grade 2 and one patient suffered from acute kidney insufficiency. Two patients were highly febrile with an elevated С-Reactive Protein (CRP) level. The WHO performance status of three was measured in all patients. Gemtuzumab ozogamicin administration was performed in three patients, followed by a further switch to Gemtuzumab ozogamicin + Azacitidine or “7+3” treatment. Results: Gemtuzumab ozogamicin administration resulted in abrupt fever cessation in two febrile patients simultaneously with a rapid decrease in CRP level and fast resolution of respiratory failure. Recovery of kidney function was noticed rapidly in patients with renal insufficiency. The WHO performance status was elevated in all three patients. No adverse grade II–III effects were noticed. Further treatment made two patients eligible for intensive chemotherapy, one patient underwent allogeneic stem cell transplantation, and the patient with kidney failure obtained complete remission. Conclusions: Gemtuzumab ozogamicin therapy appeared to be safe and highly efficacious in relapsed/refractory AML patients with organ dysfunction, like pulmonary or renal failure and poor performance status, and may contribute to rapid recovery from organ failures.