Circadian gene polymorphisms and cancer: Insights into development and risk.

The modern lifestyle imposes new stressors on our physiology, disrupting the natural adaptability and timekeeping abilities regulated by light exposure during dark hours. These chronodisruptors affect the timing of metabolic and hormonal processes, potentially interfering with homeostasis and cellular functions such as the cell cycle. Increasing evidence links such circadian disruption to an increased risk of diseases, notably cancer. Genetic variations can also influence this disturbance in circadian clock genes, which form the core components of the circadian rhythm regulatory system, including BMAL-1, CLOCK, PER 1-3, CRY 1-2, RORA, NPAS2, and TIMELESS. This review explores the potential of these polymorphisms in contributing to the timing disruptions in circadian rhythms, impacting cell cycle checkpoints like WEE1, Cyclins, and C-MYC. Further investigations into the genetic components and their relationship with cancer risk are critical for understanding their intricate connections with the circadian system and identifying novel molecular pathways that could be utilized for cancer diagnosis and prevention.