ASSESSMENT OF DNA STATUS AND PECULIARITIES OF EXPRESSION OF CYCLINS D1, E AND TRANSCRIPTION FACTOR E2F1 IN CELLS OF EPITHELIAL ENDOMETRIAL TUMORS

Iurchenko N.P., Glushchenko N.M., Buchynska L.G.

• R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Kyiv, Ukraine

Predicting the course of the tumor process is one of the urgent tasks of clinical oncology. This fully applies to endometrial cancer (EC), the incidence of which remains high. An important feature of EC is its clinical polymorphism within the same histological type and stage of the disease, which justifies the search for biomarkers, the expression of which will identify endometrial carcinomas associated with a more aggressive course of the disease. Objective: to evaluate ploidy, expression of D1 and E cyclins, and E2F1 trans­cription factor, depending on clinicopathologic features of EC. Object and methods: surgical material of 68 patients with Ec of stages stages I–II, 36 to 72 years old (mean age 59.3 ± 3.2 years), was investigated using morphological, immunohistochemical, cytofluorimetric and statistical methods. Results: it was revealed that among the tested EC samples, the aneuploid cell population was determined in 15.8% of the EC cases, the vast majority (88.9%) of which were characterized by DNA index (DNAi) > 1.0, low differentiation grade and deep invasion in myometrium (77.8%), in contrast to diploid neoplasms (54.2% and 35.4% respectively). It has been found that in endometrial neoplasms with aneuploidy there is an increase in the expression of cyclin D1 (23.4 ± 8.3%), significantly larger number of cells with expression of cyclin E and transcription factor E2F1 (25.8 ± 7.6% and 14.1 ± 1.8%, respectively) and a higher (31.1 ± 3.2%) proliferation index (PI), compared to those in diploid tumors (respectively 11.8 ± 1.6, 12.2 ± 6.9, 5.2 ± 1.7, 22.7 ± 1.4%; p < 0.05). Conclusion: It is established that among endometrioid carcinomas of the endometrium, tumors with aneuploidy are observed, characterized by mainly deep invasion of the myometrium, significantly higher PI and expression of cyclins D1, E and transcription factor E2F1 in comparison with the corresponding indices in diploid tumors. Detected phenotypic features of EC, along with DNA status, may be the basis for identifying more aggressive forms of this pathology.