MiR-15b and miR-23a have been shown to increase Cisplatin-resistance in lung cancer cell line A549 [28] and in tongue squamous cell carcinoma [29], whereas miR-29a induced Adriamycin and Docetaxel resistance in breast cancer (BC) [30], miR-128 enhanced antiblastic resistance in BC cells targeting BAX [31], miR-192 promoted Cisplatin-resistance in lung cancer cells A549/DDP [32], and, finally, miR-106b and miR-494 conferred radioresistance and Sorafenib-resistance in colorectal cancer and hepatocellular carcinoma silencing PTEN and p21 [33–35]. This evidence concerns the gene PTEN and breast cancer.