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Dysfunction of genes that control mitosis and are responsible for the correct segregation of sister chromatids in anaphase is often accompanied by aneuploidy, which is frequently detected in leukemia. One of the components of the kinetochore complex, namely, the AF15q14/KNL1/CASC5 protein, is an important factor ensuring the correct binding of the pericentromeric region of chromosomes with the spindle microtubules. As shown recently, in some leukemias, the gene of this protein can be involved in the generation of the chromosomal translocation t(11;15)(q23;q14) or a variant of the chimeric MLL-AF15Q14 oncogene, which serves as a biomarker of poor prognosis. Despite the implication of mRNA of the CASC5 gene in oncogenesis of solid tumors, expression of this gene in hematopoietic neoplasms has not been studied. We analyzed expression levels of the CASC5 gene and the nearest regulatory genes, including WT1, APOBEC3A (A3A), and N-MYC. A pronounced decrease in CASC5 expression in bone marrow cells of primary leukemia patients compared with healthy donors was found. It was also shown that reduced expression of the CASC5 gene correlates with the detection of targeted mutations in patients composed two prognostic subgroups (favorable, unfavorable) with a significance level (p

At present, cytogenetic and PCR-based techniques are generally used in the diagnosis of leukemia. Due to high accuracy, specificity, and sensitivity of PCR assays, they have the advantage over traditional cytogenetic tools. As a rule, the classical real time PCR is carried out in a 25-μL reaction mixture. It requires a large volume of each reagent and takes a long time to finish the test. The molecular genetic assay presented here is microchip-based real-time PCR that is optimized for simultaneous analysis of 15 oncogene mutations and one housekeeping gene abl. Moreover, this diagnostic tool requires a minimal amount of cDNA and PCR reagents (10-fold less) and a short time (2-fold less) for quantitative estimation of more than five copies of gene-target. Thus, microchip-based PCR analysis can improve the detection of oncogene mutations in leukemia patients and may be used for both early diagnostics and long-term monitoring of leukemia.

Genetic diagnostics is widely used for detection of risk factors of hereditary thrombophilias caused by molecular defects in the coagulation system. The hereditary thrombophilias are frequently associated with higher incidences of point mutations in hemostasis (F2 20210G>A, F5 1691G>A) and folate metabolism (MTHFR 677C>T, MTHFR 1298A>C) genes. Combinations of gene abnormalities in F2 and/or MTHFR with Leiden mutation (F5 1691G>A) significantly increase risk of thrombosis. Thus, simultaneous analysis of allele polymorphism of these genes is of clinical importance. This study has demonstrated high efficiency of microchip-based multiplex real time PCR for analysis of allele specific polymorphism in hemostasis and folate metabolism genes. Using this test it is possible to analyze polymorphism of the three genes (four point mutations) in a short time; it requires a minimal quantity of DNA template and PCR reagents including DNA polymerase, and thus can be recommended for clinical laboratory diagnostics.

In present research the comparative analysis of donor chimerism (DC) using different tests was performed to improve the diagnostic tool in patients with malignant hematological disorders after allo-HSCT. The RBC antigen typing, identification of ABO blood type and quantitative analysis of InDel-, STR-, Y-polymorphisms were carried out for detection of DC. In addition, the expression of well-known oncogenes and CD-markers for monitoring MRD was evaluated to predict relapse and clinical outcome. According to our research, the analysis of InDel polymorphism using AlleleSEQR-PCR is more sensitive test for estimation of DC as compared with other assays. Moreover, the sensitivity of AlleleSEQR-PCR may be increased after isolation of the CD34 cell population in bone marrow. Nevertheless, observation of high levels in DC (³95%) in some leukemia patients (ALL, Ph+, bcr-abl/p190+) during first 6 months after HSCT cannot exclude the possibility of relapse. Thus, the combined monitoring of both DC (InDel) and MRD (oncogenes, WT1 and CD-markers) is a more advisable and useful test in managing hematologic malignancies and predicting relapse risk after allo-HSCT.S tsel'iu uluchsheniia diagnostiki u onkogematologicheskikh patsientov v posttransplantatsionnyĭ period provodili kompleksnoe issledovanie biomarkerov-misheneĭ donorskogo khimerizma (DKh) s ispol'zovaniem neskol'kikh testov. Vyiavlenie biomarkerov DKh vkliuchalo fenotipirovanie antigenov éritrotsitov s identifikatsiĭ gruppy krovi, a takzhe opredelenie polimorfizma InDel-, STR-, Y-lokusov DNK. Krome togo, dopolnitel'no vypolniali analiz biomarkerov minimal'noĭ ostatochnoĭ bolezni (MOB), sostoiashchiĭ iz obnaruzheniia khromosomnykh aberratsiĭ, ékspressii onkogenov i CD-markerov. Pokazano, chto naibolee chuvstvitel'nym metodom otsenki DKh iavliaetsia analiz polimorfizma InDel-lokusov DNK s ispol'zovaniem kolichestvennoĭ PTsR (AlleleSEQR-PCR). Pri étom tochnost' testirovaniia mozhet byt' povyshena posle selektirovaniia kletok-predshestvennits CD34 iz kostnogo mozga s ispol'zovaniem protochnoĭ tsitometrii. Tem ne menee, obnaruzhenie povyshennykh urovneĭ DKh (³95%) u nekotorykh bol'nykh leĭkozom, v chastnosti, pri OLL (Ph+, bcr-abl/190+), v techenie pervykh 6 mesiatsev posle allo-TGSK, ne iskliuchaet razvitiia retsidivov. Poétomu, vypolnenie kombinirovannogo analiza biomarkerov-misheneĭ DKh (InDel) i MOB (onkogeny, WT1, CD-markery) u bol'nykh onkogematologicheskimi zabolevaniiami posle allo-TGSK iavliaetsia bolee tselesoobraznym. Éto pozvoliaet éffektivnee kontrolirovat' techenie zabolevaniia i prognozirovat' razvitie retsidivov v posttransplantatsionnyĭ period.

Leukemia is a clonal proliferative disorder of a multipotent hematopoietic stem cell that leads to abnormal cell growth and/or differentiation. The hallmark of the disease is the presence of oncogene expression in bone marrow or peripheral blood resulting from chromosome translocations. The development of leukemia and the progression of the disease are multistage processes implicated in a series of molecular changes preceeded chromosomal instability and aneuploidy. The most likely of the above-mentioned changes include the following: the appearance of additional chromosome translocations, the activation of other oncogenes not expressed previously, the loss of tumor suppressor genes, abnormal centrosome duplication, and the dysfunction of genes that coordinate accurate chromosome alignment and chromosome segregation during mitosis. The last two molecular events controlled by mitotic spindle checkpoint genes play a role in leukemogenesis and are probably involved in apoptosis.

A neural expert network system for diagnosis and prognosis of cardiovascular diseases was developed. Computer experiments using the system revealed that the current medical practice of recommending hypocholesteric diet, avoidance of pernicious habits, limitation in consumption of coffee and alcohol, sliming, and reduced physical and mental load to all cardiologic patients is not universally correct. It is demonstrated that some of these recommendations can even prove harmful to some patients. The diagnostic system suggested in this work allows such atypical patients to be recognized and personal recommendations for such patients to be compiled.