Influence of circadian rhythms in tumorigenesis–Role of vanillic acid on liver cancer

Rhythmicity is observed in transcriptional expression of a wide range of clock-controlled genes which regulate a variety of normal cell functions like cell division and proliferation. The human circadian timing system functions to co-ordinate humoral, physiological, and behavioral mechanism to promote sleep and waking behavior. The rhythms are generated by neural structures in the hypothalamus that function as a biological clock. Modern lifestyle is also turning to be a relevant factor promoting desynchrony, especially in individuals staying for long hours awake during the night and with disturbed sleep patterns. Chronotherapeutics is relatively new concept in medicine. The main goal of chronotherapeutics is the enhancement of the desired effects of medications and control of their adverse effects. This review addresses the role of circadian rhythms in tumorigenesis.