Downregulation of hPer1 expression in mouse mammary carcinoma cells or human oral squamous cell carcinoma can alter cell cycle distribution, promote cell cycling, and reduce apoptosis (Borgs et al., 2009; Yang et al., 2009; Soták et al., 2014; Zhao et al., 2016). The gene discussed is PER1; the disease is oral cavity squamous cell carcinoma.