CDK6 and esophageal squamous cell carcinoma: As shown in Figure 4D, depletion of RECQL4 led to decreased expression of c-myc, cyclin D, CDK6, and cyclin E. Overall, these results showed that the inhibitory effects of RECQL4 depletion on the proliferation of ESCC cells might be mediated by p21 upregulation and the downregulation of mitogenic genes.