5-FU and ixabepilone modify the microRNA expression profiles in MDA-MB-453 triple-negative breast cancer cells

This study aimed to discover new potential mechanisms of chemotherapy with drugs used in the treatment of luminal androgen receptor (LAR)-type triple-negative breast cancer (TNBC). We examined the microRNA (miRNA) expression profiles of LAR-type TNBC in vitro, and explored the variation in miRNA expression profiles in cells when treated with the chemotherapy drugs capecitabine and ixabepilone. The present study revealed that the expression levels of the three antitumor miRNAs, miR-122a, miR-145 and miR-205, were significantly elevated in MDA-MB-453 LAR-type TNBC tumor cells treated with 5-fluorouracil together with ixabepilone. By contrast, carcinogenic miR-296 miRNA expression significantly declined, and levels of several other miRNAs such as miR-221, miR-210, miR-21 and miR-10b were also altered. The drugs may exert their effects through the regulation of miRNA expression levels, thereby providing a theoretical basis for clinical implementation of miRNA expression profiles as a diagnostic method for the early diagnosis, classification and prognosis of breast cancer.