Compared to those in normal colon tissues, the transcriptional levels of CLOCK, CRY1, and NR1D1 in COAD tissues were significantly higher, while the mRNA levels of ARNTL, CRY2, PER1, PER3, and RORA in COAD tissues were downregulated in the current study. This evidence concerns the gene CRY2 and colon adenocarcinoma.