Specifically, miR-27a directly bind to UTR of cystine/glutamate transporter (xCT) and cystathionine gamma-lyase (CTH), whereby cystine uptake and production, respectively, are compromised, leading to a decrease in mammosphere formation and cancer stem cell markers as well as an increase in sensitivity to doxorubicin and paclitaxel [36]. This evidence concerns the gene SLC7A11 and cancer.