Examining the expression of circadian genes in cancer has incidentally revealed that TIMELESS is frequently overexpressed in breast cancer [10–12], colon cancer [13], lung cancer [14], and cervical cancer [15].Based on the overexpression of TIMELESS in cancer and its described mechanisms of action that could support high fidelity and rapid DNA synthesis, it is likely TIMELESS plays a role in maintaining aberrant cancer cell proliferation. This evidence concerns the gene TIMELESS and breast cancer.