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Molecular genetic detection of CALR gene somatic mutations is required for myeloproliferative neoplasms diagnosis and treatment according to the novel WHO clinical recommendations. CALR mutations are found in approximately 25–35 % cases of essential thrombocythemia and primary myelofibrosis and they are associated with benign clinical outcome. In this study we have compared sensitivity and selectivity of seve ral different options of CALR mutation molecular genetic detection in blood samples of 379 CMD patients and 17 healthy donors. Among methods compared in our study there have been conventional polymerase chain reaction with electrophoretic detection, real-time quantitative polymerase chain reaction, direct Sanger sequencing of polymerase chain reaction fragments and polymerase chain reaction high resolution melting curve analysis. By means of melting curve analysis CALR mutations have been found in 97 (25.5 %) patients, whereas in the cases of Sanger sequencing and polymerase chain reaction there have been 87 (23.0 %) and 84 (22.1 %) CALR mutation positive patients respectively.

Background. Kinase domain mutations of BCR-ABL gene is the most common cause of tyrosine kinase inhibitor resistance. Aim. To present the data on prognostic value of BCR-ABL mutation burden in Russian patients over the last 10 years. Materials & Methods. The study included 1885 chronic myeloid leukemia (CML) patients with tyrosine kinase inhibitor resistance who were followed up from 2006 to 2016. BCR-ABL point mutations in mRNA samples were analyzed by means of polymerase chain reaction and subsequent Sanger sequencing. Results. In 1257 CML patients with signs of tyrosine kinase inhibitor resistance BCR-ABL expression level was > 1 %. BCR-ABL mutations were detected in 31.8 % of patients. Total mutation count was 467 (70 mutation types). Total count of patients with mutation-associated tyrosine kinase inhibitor resistance decreased from 36.6 % (2006-2008) to 24.95 % (2013-2016) and to marked decrease of 23.12 % in 2014. Detection rate of imatinib-resistant mutations and F359V mutation was shown to decrease within the period from 2010-2011 to 2014-2015. F317L level, which is responsible for dasatinib resistance, considerably increased in 2015. T315I frequency was the highest in 2014, afterwards it was gradually decreasing. Mutation-associated resistance rates varied by region of the Russian Federation. Conclusion. The analysis of trends of mutation incidence in patients with CML can be of extreme significance in longterm prognosis of resistance development and in improvement of treatment planning.

Background. The V617F mutation of JAK2 is known to manifest in Ph-negative chronic myeloproliferative diseases (cMPD), such as polycythemia vera, thrombocythemia, and myelofibrosis. These diseases not infrequently advance into more aggressive forms up to acute leukemia. As the progression mechanism is still unknown, its study retains a high priority. JAK2 carrying the V617F mutation is believed to cause constant activation of V(D)J recombinase in myeloid tumor cells in cMPD patients. Aberrant activation of V(D)J recombinase in tumor cells in cMPD patients can lead to t(9;22)(q34;q11) chromosomal rearrangement. Aim. To study the expression of BCR-ABL1 resulting from translocation t(9;22)(q34;q11) in cMPD patients at the progression stage in order to test the suggested hypothesis. Materials & Methods. The BCR–ABL1 expression was assessed in peripheral blood granulocytes in cMPD patients by real-time PCR. The JAK2 V617F mutation was identified by quantitative allele-specific PCR. The JAK2 exon 12 mutations were determined using Sanger direct sequencing of PCR products. Results. The BCR-ABL1 expression was discovered in 29 % of patients with cMPD progression. The BCR-ABL1 expression in these patients correlated with hepatosplenomegaly and hyperleukocytosis. Conclusion. In a significant proportion of cMPD patients the disease progression can be associated with activation of the BCR-ABL expression.

A growing number of evidence indicates that cancer-testis antigens (CTA) can be used as specific targets for immune therapy of malignant melanoma. The aim of this study was to provide a basis for selecting the most suitable CTA by analyzing the mRNA expression profile of genes encoding CTA in melanoma cell lines. We used a real-time quantitative PCR to measure the expression level for the following genes: GAGE1, NY-ESO-1, MAGEA1, PASD, SCP1, SEMG1, SPANXA, SSX1, and PRAME. The objects of study were cell lines mel P, mel Si, mel Mtp, mel Il, mel Hn, mel Ibr, and mel Kor obtained from patients diagnosed with disseminated melanoma. We established that the highest frequency of occurrence and the highest expression level had the following genes: GAGE1, NY-ESO-1, MAGEA1, SCP1, SPANXA, SSX1, and PRAME. Their mRNA translation products can be promising candidates for immunotherapy.

Quantitative indices of feeding, food assimilation, energy metabolism and growth in Pontogammarus maeoticus (Sow.) from the Azov Sea (12‰S) were studied from the salinity levels. Juveniles and males of different age groups were sampled for experiments. The relationships between feeding rate (C) and energy metabolism (R) on an energy equivalent of w, body weight were approximated by the power equations \(C = C_1 w^{b_c }\) and R=R1wb. To express weight growth, the Bertalanffy equation and its solution were used: $$\frac{{dw}}{{dt}} = Nw^q - kw; w(t) = W_\infty (1 - e^{ - mkt} )^{1/m}$$ Under control salinity (12‰S) the following parameters were obtained: C1=0.73J(1-b)d-1; bc=0.62; R1=0.53J(1-b)d-1; b=0.67. The application of a new method suggested by the author for determining the growth parameters, N, k, m=1-q, revealed their dependence on age. For juveniles N=0.0965, k=0.0046, while for adults the respective values were 0.1540 and 0.0181. The value m=0.39 was the same for both age classes. The individuals were gradually transferred to conditions of changed salinity (∼0; 4 and 18‰S). The observations lasted up to two months. Through the entire range of salinity (∼0–18‰S), food assimilation alone was constant. In relation to dry matter, food assimilation was 65 and 80% in terms of caloric value. The other indices under study remain at the control level only under desalinization to 4‰S. When P. maeoticus was maintained in fresh water, the juveniles showed enhanced levels of nutrition, energy metabolism and increment, while in mature individuals the respective parameters decreased compared with the control. As a result, the parameters C1 and R1 in the functions C(w) and R(w) were ∼2 times higher and bc and b∼2 times lower than in 12‰S. An increase in salinity to 18‰S resulted in a decline of all the processes concerned: C1=0.61, R1=0.36, bc and b remained at the control level, while growth rate became 20% lower. A full compensation type acclimation for P. maeoticus is possible with the salinity range (12–4‰S) where the individual can maintain ionic balance.