PER2 and colon adenocarcinoma: As shown in Figure 10, the expression levels of CRY2 (Figure 10(a), P value = 0.00016), NR1D1 (Figure 10(b), P value = 2.5E − 05), and PER2 (Figure 10(c), P value = 0.0089) were associated with the clinical stage of COAD patients, which demonstrated that these 3 genes might be involved in the development of COAD.