MTT cell proliferation assays revealed that specific silencing of TLK2 by esiRNA or siRNA potently inhibited the growth of TLK2-high breast cancer cells (MCF7, MDAMB361 and CAMA1), but not that of the TLK2-low luminal ZR75-1 breast cancer cells or MCF12A and MCF10A benign breast epithelial cells (Fig. 4a). This evidence concerns the gene TLK2 and breast cancer.