MicroRNA-155-5p promotes tumor progression and contributes paclitaxel resistance to chemotherapy via TP53INP1 in human Breast Cancer

Abstract Background MicroRNAs (miRNAs) are a class of small, non-coding RNAs that functioned by targeting specific mRNA. Many studies have reported that, miRNAs play a vital role in cancer progression, they can exert their functions as oncogenes or cancer suppressors. As suggested in previous report, miR-155-5p is up-regulated in breast cancer. Results Here, we found that miR-155-5p promoted cell proliferation and inhibited cell apoptosis in MCF-7. In addition, these effects were reversed when high levels of miR-155-5p were suppressed in MCF7/PR. We determined that TP53INP1 served as a direct target of miR-155-5p through bioinformatic and luciferase assay. These findings confirmed that miR-155-5p was a tumorigenic factor that acted by targeting TP53INP1 and promoted tumor progression and contributed paclitaxel resistance to chemotherapy. Conclusions These results contribute to our understanding of the molecular mechanism underlying breast cancer progression and resistance to chemotherapy.