Circadian clock and cancer

Circadian rhythms play a critical role in regulating physiological and behavioral processes, such as the sleep-wake cycle, hormone secretion, and metabolism. These rhythms are controlled by endogenous biological clocks, which are synchronized with environmental cues, primarily the light-dark cycle. Notably, disruption or reprogramming of circadian rhythms is closely associated with cancer initiation, progression, and treatment response. At the molecular level, the dysregulation of core clock genes can disturb normal cellular rhythms, leading to aberrant cell proliferation, impaired DNA repair, altered metabolism, and disrupted immune responses. This review systematically summarizes the pivotal roles and molecular mechanisms of circadian rhythms in tumor development, with a particular focus on strategies to modulate clock genes through behavioral interventions, pharmacological approaches, and gene-editing techniques, highlighting their potential as novel therapeutic strategies and clinical applications in cancer management.