TRF2 was found to be expressed at significantly higher levels (approximately two- to eightfold) in several breast cancer (MDA-MB-453, MDA-MB-468, ZR-75-1 and MCF-7) and melanoma cell lines (LOX, WM115, WM278, WM983A and WM1158) compared with the primary cells (IMR90, BJ and WI38) (Fig. 1a, Supplementary Fig. 1a), consistent with observations reported by other groups23, 33, 34, 35. This evidence concerns the gene TERF2 and breast cancer.