Alterations in circadian clock genes or their functions can lead to disrupted cellular activities linked with cancer hallmarks, including cell cycle disruption (Lévi et al., 2007; Qu et al., 2023), genomic instability (Zhang et al., 2023), metabolic reprogramming (Chun et al., 2022), and immune system dysregulation (Chen et al., 2020; Zhang et al., 2024). The gene discussed is CLOCK; the disease is cancer.