For instance, it is known that the CLOCK gene product activity can affect both estrogen [21] and androgen pathways [22], which is concordant with the relationship between circadian pathway perturbation and the risk of hormone-driven malignancies such as breast and prostate cancer, respectively; however, the association with lung carcinoma remains less intuitive and warrants further investigation on the cascade of molecular events underlying the link between the biological clock and this type of tumour. This evidence concerns the gene CLOCK and prostate cancer.