According to the ploidy of the cancer cells, the average tumour/benign fold change in mRNA levels were similarly expressed for the clock genes except for BMAL1, CRY2 and CSNK1A1L. The average expression of BMAL1 was slightly up-regulated in the aneuploid cells while CRY2 was slightly down-regulated for the aneuploid cells and up-regulated in the diploid cells. This evidence concerns the gene CLOCK and cancer.