Submitted to: Journal of Supportive Oncology
Publication Type: Review Article
Publication Acceptance Date: 4/1/2007
Publication Date: 4/1/2007
Citation: Fu, L. 2007. Understanding the mechanism of circadian modulation to improve the quality of life for cancer patients. Journal of Supportive Oncology. 5(4):176-177. Interpretive Summary:
Technical Abstract: The strategy of anticancer treatment varies for different types of cancers, but most of them are aimed at inducing cell-cycle arrest or apoptosis in proliferating tumor cells by generating genomic DNA-damage or blocking intracellular mitogenic signaling. Although these treatments could reduce the rate of tumor growth or result in tumor remission, they are universally limited by their toxicity in vivo, which often causes unpleasant side effects that not only reduce the quality of life for patents but also impair treatment. These treatments can also damage normal host tissues that need cell proliferation for their function, leading to further unwanted side effects. Thus, it is suggested that anticancer treatments could be improved if they are applied at a time when host tissues are less sensitive to the treatment. However, recent developments in our knowledge of circadian rhythms indicate that changes in the time of anticancer administration alone may not significantly improve the therapeutic index. Therefore, to develop new tools and methods for improving current cancer therapy, the mechanism governing the response of cancer patients to treatments needs to be studied further. The article by Dr. Rich discusses the common symptom cluster (fatigue, appetite loss, sleep disruption, and depression) that is often observed among cancer patients and is frequently associated with poor therapeutic response and cancer prognosis. The hypothesis that the modulation of the circadian axis by the inflammatory cytokines produced by cancer or anticancer treatment could be one of the processes leading to these symptoms.