The circadian rhythm has an impact on the development of cancers, and could thus be used to better diagnose and treat malignant tumours.
- The circadian cycle plays a role in the development of cancers.
- Better understanding the link between the circadian rhythm and cancer can help develop better treatments and diagnostic tools, researchers say.
- The impact of the circadian cycle is different for each cancer.
Your circadian cycle doesn’t just impact your sleep, it also appears to play a role in the development and treatment of cancer. This is what a review article published in the journal reveals Trends in Cell Biology on March 24, 2023.
The circadian rhythm influences cancer and its metastases
The circadian cycle helps our body synchronize different functions over the 24 hours of a day: sleep obviously, but also gene expression, immune function and cell repair. If the latter is disturbed, the risks of several diseases increase, including those of cancer.
After a review of 110 studies on the subject, researchers from ETH Zurich indicate that “the circadian rhythm governs most of the cellular functions involved in cancer progression”and thus plays a role in the appearance of metastases.
The rate at which cancer cells break away from the primary tumor and enter the bloodstream to form metastases in other parts of the body varies throughout the day depending on the circadian cycle. The rhythm differs according to the tumours: the release is greater at night for breast cancer. For prostate cancer or myeloma, it occurs at other times of the day.
Faced with these elements, the scientists assure that it would be interesting to rely on the circadian cycle to treat patients. This method, which consists of administering drugs at specific times of the day to maximize their effectiveness, is called chronotherapy.
Cancer: the circadian cycle can help manage it
“The formation of metastases based on the circadian rhythm must be considered as an opportunity to intervene in the fastest and most effective way”write molecular oncologists Zoi Diamantopoulou, Ana Gvozdenovic and Nicola Aceto of ETH Zurich. “Chronotherapy promises to be a valuable alternative treatment option in the fight against cancer.”
Scientists note, among other things, that this method seems to reduce the severity of side effects experienced by patients. In a recent study reviewed, melanoma patients who had their chemotherapy before 4:30 p.m. were almost twice as likely to survive compared to those who had it later in the day. However, the optimal timing varies by tumor type and care.
The team adds that a better understanding of the interactions between the circadian cycle and tumors could also facilitate diagnoses. Indeed, cancer cells produce proteins, some of which are diagnostic markers – at different rates throughout the day. Identifying these could help make screenings more effective and reduce misdiagnosis.
