Evaluation of changes in miR-4673 and its target gene Xrcc-3 expression in tumor samples and healthy margin around the tumor in breast cancer patients

Abstract

Breast cancer is the second most common cancer and the fifth leading cause of cancer death in Iran. Cancer is usually caused by abnormal cell cycle progression and incomplete apoptosis due to the activation of potentiogens and the inactivation of tumor suppressor genes. One of the target genes, P53, has received a great deal of attention due to its participation in a very large area of tumors (about 55%). The study of autophagy-related miRNAs in cancer provides insights into cancer biology and leads to the development of new anti-cancer strategies. Direct targeting of the Xrcc-3 by the miR-4673 completes the indirect inhibition of P53. Considering the important role of autophagy in cancer and the pathogenesis of this disease, the aim of this study was to investigate the changes and Xrcc-3 gene in cancerous and healthy samples in breast cancer patients to help better understand this process. Methods: In this study, the expression of miR-4673 and its target gene Xrcc-3 were investigated. In this study, RNAs of 50 samples from tumor tissue and 50 samples from tumor margins of cancer patients were extracted using trisol and used for cDNA synthesis. Then, the expression of the desired gene was examined by Real Time PCR. Results: Using qRT-PCR, the expression of miR-4673 expression and its target gene XRCC-3 were examined in internal breast cancer tissue samples and healthy tissue samples. The sample size was 50. The mean age was 56.7 years, with 21 samples under 55 years and 29 samples over 55 years. 7 patients had stage 4, 19 samples had stage 2 and 24 patients had stage 3. 21 samples were lymphatic negative and 29 samples were positive. 10 patients had no history of chemotherapy and 40 samples mentioned this history. In the study of miR-4673 expression and its target gene XRCC-3, no statistically significant relationship was found between their incidence in cancerous tissue and healthy tissue.