The role of circadian and redox rhythms in cancer hypoxia

Cancer therapy faces considerable challenges due to the gaps in the understanding of the interlinked aspects of the relevant modalities. Hypoxia, altered circadian rhythms, and altered redox rhythms are some of the central and therapeutically targetable, relevant modalities. Recent studies suggest the existence of bi-directional crosstalk between hypoxia-circadian rhythm, hypoxia-redox rhythm, and redox-circadian rhythms. However, the interconnections between the three modalities are not yet established in cancer pathophysiology. This work reviews the recent investigations on the interconnected roles of circadian clock oscillations, redox oscillations, and hypoxia in cancer. Based on the available data, we highlight the gating of the hypoxic signaling pathway by the two oscillatory systems. An understanding of the molecular coupling is expected to result in better cancer therapies through drugs that modify circadian rhythm, redox rhythm, and hypoxia.