CHEK2-GENE POLYMORPHISM IN BREAST CANCER PATIENTS IN KABARDINO-BALKARIA.
Breast cancer (BC) is the most common cancer in women. The chance of getting breast cancer in a lifetime is about 12%. Approximately 5-10% of breast cancer cases in women are familial cancer, when tumors occur at a relatively young age, affect the mammary glands and ovaries, and the risk of developing cancer in close relatives is also high. The frequency of hereditary cancer associated with mutations in the genes BRCA1, BRCA2, TP53, PTEN, CHEK2, etc., is 5-10% of all cases, including sporadic and hereditary forms. The study of the relationship between the presence of mutations and the risk of breast cancer is a topical and actively studied area in oncology and oncogenetics. To date, it has become possible to investigate the carriage of more than 2000 mutations in the coding sequences of genes associated with the likelihood of breast cancer, including mutations in the CHEK2 (checkpoint kinase) gene. The main role of this gene is participation in the control of the cell cycle and the repair of DNA damage. For the first time, mutations in the CHEK2 gene were found in the work of Bell et al., which indicated 3 mutation points in individuals with hereditary Li-Fraumeni syndrome - these are 2 variants 1100delC and a variant 470T>C (Ile157Thr). These studies began a broad study of polymorphism in this gene and its relationship with predisposition to breast cancer. In this regard, the purpose of this work is to study the frequency of occurrence of highly penetrant CHEK2 mutations (1100delC, Ile157Thr) in breast cancer patients and healthy residents of Kabardino-Balkaria, as well as to analyze the clinical and morphological characteristics of the studied patients with breast cancer (study of family history, age composition , peak disease manifestation and tumor size).