Comparison of CYP3A4 immunohistochemical expression in proliferative endometrium, endometrial hyperplasia, and endometrioid endometrial carcinoma

Aim: Unopposed chronic estrogen exposure is responsible for the development of endometrial cancer. Cytochrome P450 3A4 (CYP3A4) converts estradiol into metabolites with weaker estrogenic effects in tissues. This effect may protect tissues against the harmful effects of estrogen. In this study, the relationship between the CYP3A4 enzyme and endometrial cancer was investigated.Material and Methods: A total of 60 women diagnosed with proliferative endometrium, endometrial hyperplasia, and endometrioid adenocarcinoma were included in the study. The endometrial gland and stroma expression were evaluated by immunohistochemical staining for the CYP3A4 enzyme.Results: Glandular staining with CYP3A4 was most intense in the endometrial cancer group, consistent with the course of the disease. Moreover, the stromal staining percentage was lower in the endometrial cancer group than in the proliferative endometrium group. The glandular staining percentage and stromal intensity were similar in all groups.Conclusion: CYP3A4 expression is increased in endometrial glands during malignant transformation. This may reflect a compensatory response to chronic estrogen exposure, although its exact role remains unclear.