Circadian rhythm governs our sleeping schedule and now a new study demonstrates how it can also impact cancer development, diagnosis, and treatment. Researchers from ETH Zurich in Switzerland uncovered how circadian rhythms in tumor progression spread and described how we could better time when patients are tested for cancer and when they receive therapies to improve treatment success.
The findings are published in Trends in Cell Biology in a paper titled, “A new time dimension in the fight against metastasis.”
“Despite advances in uncovering vulnerabilities, identifying biomarkers, and developing more efficient treatments, cancer remains a threat because of its ability to progress while acquiring resistance to therapy,” wrote the researchers. “The circadian rhythm governs most of the cellular functions implicated in cancer progression, and its exploitation, therefore, opens new promising directions in the fight against metastasis. In this review, we summarize the role of the circadian rhythm in tumor development and progression, with emphasis on the circadian rhythm-regulated elements that control the generation of circulating tumor cells (CTCs) and metastasis.”
“The circadian rhythm governs most of the cellular functions implicated in cancer progression, and therefore its exploitation opens new promising directions in the fight against metastasis,” wrote the authors, molecular oncologists Zoi Diamantopoulou, PhD, Ana Gvozdenovic, PhD, and Nicola Aceto, PhD, from the ETH Zurich in Switzerland.
More recent studies have shown that circadian rhythms are not only involved in tumor onset, but also govern cancer progression and metastasis, the colonization of secondary sites within the body.
The authors argue that we could leverage this information when administering chemo- and immunotherapies to target tumor cells at the optimal time. The practice of delivering medication and immune therapies at specific times of day is known as chronotherapy.
“Circadian rhythm-based metastasis formation should be seen as an opportunity to intervene in the most timely and effective way,” the authors wrote. “Chronotherapy holds promise to be a valuable alternative treatment option in the fight against cancer.”
Clinical studies have shown that chronotherapy can reduce the severity of side effects experienced by patients and can also impact treatment effectiveness. For example, the authors described a recent study in which melanoma patients who received immunotherapeutic drugs before 4:30 pm were nearly twice as likely to survive as patients who received the treatment later in the day.
“More mechanistic understanding of these processes will be required to fully unleash its potential on the clinical side,” the authors wrote. “Defining the circadian-rhythm-controlled timing of proliferation and release of circulating tumor cells into the bloodstream in additional cancer types may help to identify the optimal time window for therapy administration.”