Disruption of circadian rhythms has been identified by the World Health Organization (WHO) as an independent risk factor for cancer. A paper by American scientists outlines the main regulatory functions of the circadian rhythm and its relevance to the development and treatment of cancer.

Research shows that disruption of circadian rhythms contributes to the development of tumours, while their proper functioning can contribute to treatment and prevention

Research has shown that disruption of circadian rhythms is a significant risk factor for cancer and the WHO has classified it as a carcinogen. Clock genes that control the circadian clock, such as CLOCK and BMAL1 (which form the core of the circadian clock), act as tumour suppressors, and mutations in these genes increase the risk of breast, prostate and pancreatic cancers. Their disruption also affects metabolism and inflammatory processes in the body, which can also promote the development of cancer. Proper function of clock genes, on the other hand, can prevent uncontrolled cell division and growth.
At the same time, circadian rhythms affect the cell cycle – the different phases of cell division are cyclical and can be disrupted if the circadian clock is not functioning properly. Dysfunction of this clock can lead to uncontrolled growth of cancer cells.

Chronotherapy, using modulation of circadian rhythms, represents a promising approach in cancer treatment

Light chronotherapy, which takes the body’s natural rhythms into account when treating diseases, including cancer, has been shown to improve the effectiveness of chemotherapy and reduce its side effects.