CLOCK and cancer: Moreover, in a xenograft model, EGCG suppressed the cancer stem-cell-like features (CD133, CD44, Sox2, Nanog and Oct4 protein) of A549 and H1299 cells by targeting CLOCK, suggesting EGCG is a compound with chronotherapeutic potential to inhibit the self-renewal capacity of lung cancer stem-like cells by modulating CLOCK [101].