Abstract
Triple-negative breast cancer (TNBC), lacking estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor (HER2) expression, is resistant to conventional therapies. Recent studies have focused on microRNAs (miRNAs) as novel molecular targets for treating TNBC because they modulate gene expression and tumor progression. In the current study, we analyzed the expression of selected miRNAs (miR-145 and miR-182) and tumor promoting factors such as Fascin and poly (ADP-ribose) polymerase (PARP) in human TNBC tissues and “Luminal A” breast cancer tissues, which express ER and PgR, but not HER2, as well as breast cancer cell lines including the triple-negative MDA-MB-231 and Luminal A MCF-7. The results showed that miR-145 and miR-182 were expressed in Luminal A breast cancer tissues and MCF-7 cells, but not in TNBC tissues and MDA-MB-231 cells. In contrast, Fascin and PARP proteins were highly expressed in TNBC and MDA-MB-231, but poorly expressed in Luminal A tissues and MCF-7 cells, indicating a negative correlation between expression of these miRNAs and that of the tumor promoting factors Fascin and PARP. The current study therefore suggests that miR-145 and miR-182 could be potential novel therapeutic targets for TNBC therapy.
