Extracellular glycoproteins of the laminin family are essential components of basement mem branes involved in a number of biological processes, including tissue differentiation, wound healing, and tum origenesis. We present the first comprehensive study of promoter methylation status of the genes encoding laminin chains in normal tissues (peripheral blood leucocytes, buccal epithelial cells, autopsy breast tissue samples) and in breast carcinoma samples. Based on the results of this study, we divide laminin genes into three categories. Genes, constitutively methylated in breast tissues include LAMA3A, LAMB2, LAMB3, and LAMC2. Genes prone to abnormal methylation in breast carcinoma include LAMA1, LAMA2, LAMA3B, LAMA4, LAMB1, and LAMC3. Genes that are rarely if ever methylated in breast carcinoma include LAMA5 and LAMC1. The constitutively methylated group includes all of the genes that encode subunits of laminin 5 (the historical name of laminin 332), the promoters of which were previously considered unmethylated in normal tissues and prone to abnormal methylation in breast cancer.

26М а м м о л о г и я / M a m m o l o g y 1 ' 2 0 1 6 Том 12 / Vol. 12 ОПУХОЛИ ЖЕНСКОЙ РЕПРОДУКТИВНОЙ СИСТЕМЫ TUMORS OF FEMALE REPRODUCTIVE SYSTEMДиагностика Введение Исследование молочных желез -одна из актуаль-ных проблем современной лучевой диагностики. В боль-шинстве стран мира рак молочной железы занимает 1-е место среди онкологических заболеваний у женщин. Единственным путем успешного снижения смертности от рака молочной железы в настоящее время является улучшение ранней диагностики, которая включает в се-бя дифференциальную диагностику добро качественных и злокачественных опухолей молочных желез. Точная ранняя дифференциальная диагностика позволяет свое-временно начать адекватное лечение.Общепринятое стандартное обследование пациен-ток с заболеваниями молочных желез включает: кли-нический осмотр, рентгеновскую маммографию в со-четании со специальными методиками, ультразвуковое исследование (УЗИ) молочных желез, особенно в воз-растной группе до 35 лет, в случае необходимости -диаг ностическую пункцию. В последние годы широкое применение высокотехнологических диагностических методов привело к резкому увеличению случайно вы-явленных образований, требующих дальнейшей ква-лифицированной дифференциальной диагностики. Так, при маммографии до 25 % опухолей отнесены к разряду «сверхдиагностики», которая увеличивает стоимость диагностических исследований, но не при-носит пользу пациентке, так как выявленное заболе-вание не угрожает ее здоровью

Extracellular glycoproteins of the laminin family are essential components of basement membranes involved in a number of biological processes, including tissue differentiation, wound healing, and tumorigenesis. We present the first comprehensive study of promoter methylation status of the genes encoding laminin chains in normal tissues (peripheral blood leucocytes, buccal epithelial cells, autopsy breast tissue samples) and in breast carcinoma samples. Based on the results of this study, we divide laminin genes into three categories. Genes, constitutively methylated in breast tissues include LAMA3A, LAMB2, LAMB3, and LAMC2. Genes prone to abnormal methylation in breast carcinoma include LAMA1, LAMA2, LAMA3B, LAMA4, LAMB1, and LAMC3. Genes that are rarely if ever methylated in breast carcinoma include LAMA5 and LAMC1. The constitutively methylated group includes all of the genes that encode subunits of laminin-5 (the historical name of laminin 332), the promoters of which were previously considered unmethylated in normal tissues and prone to abnormal methylation in breast cancer.

Background: AB0 blood type antigens are unequally expressed in different portions of the colon resulting in so-called proximal-distal gradient. In most research studies considering the link between blood types and colorectal cancer, this gradient has not been taken into account. In the present context the findings of such studies are not convincing, no evidence-based results are reflected in literature. Valid studies of this association require antigenic distribution of the colon and malignant tumor location to be taken into account.Aim: To assess the possible relation between AB0 blood type antigens and malignant tumors located in different parts of the large intestine.Materials and methods: We performed a case-control study with retrospective analysis of medical records on patients with the presented disease (cases) and patients who did not suffer from it (controls). Required data was obtained from regional oncological centers of South Kazakhstan, Karaganda, East Kazakhstan, and Mangystau regions. Every third case of colorectal cancer registered in 2011−2016 years was included in the survey. The studied association was estimated by means of a chi-square test. A multinomial logistic regression was used to calculate the odds ratio (OR) with confounding risk factors to be taken into account. Shares of the samples were compared by means of Student’s t-test. A critical level of statistical significance (p-value) was considered to be 0.05.Results: Each group included 1570 patients. Gender, age, and ethnic distribution did not differ statistically in cases and controls (p0.4 for all comparisons). When blood type distributions were compared between groups regardless of tumor locations, any significant difference was not revealed (p=0.141). When similar calculations were applied to specific parts of the large intestine, the association between 0 blood type and malignancies of distal portions of the colon was demonstrated (p=0.0002). When we calculate the odds ratio for the disease development in the colon parts (using a multinomial logistic regression), the following results were obtained: 1.518 (p=0.004) for 0, 0.781 (p=0.099) for A, 0.785 (p=0.143) for B, and 0.965 (p=0.884) for AB blood types.Conclusions: The results of the present study revealed a statistical correlation between the 0 blood type and malignant tumors located in the distal portions of the colon.

ОПУХОЛИ ЖЕНСКОЙ РЕПРОДУКТИВНОЙ СИСТЕМЫ TUMORS OF FEMALE REPRODUCTIVE SYSTEM Г и н е к о л о г и я / G y n e c o l o g y игина н стат и Г и н е к о л о г и я / G y n e c o l o g y