System biology analysis reveals circadian rhythm disorder associated with development and progression in colorectal cancer

Abstract Circadian rhythm disorders represent an abstract concept lacking standardized quantitative metrics. Existing circadian indicators, including traditional rhythm parameters and a limited set of clock gene or physiological biomarkers, are insufficient to robustly capture steady-state endogenous circadian homeostasis in complex disease contexts, thereby constraining quantitative assessment of circadian disruption and limiting its translational applicability. Chronic circadian rhythm disruption is associated with various diseases, including metabolic disorders and malignancies. However, the mechanisms by which circadian disruption influences tumor microenvironment formation and colorectal cancer progression remain incompletely understood. This study employs systems biology analysis to decipher the molecular characteristics of circadian rhythm disruption in colorectal cancer progression. We analyzed single-cell RNA sequencing data from 13 CRC tissue samples and 12 normal mucosal samples, combined with 3733 samples from 34 public batch RNA, microarray, and single-cell RNA sequencing cohorts. We developed and validated the ClockProCRC system, which detects and quantifies intrinsic circadian misalignment in CRC. The ClockProCRC score elucidates how circadian misalignment drives CRC progression trajectories, shapes clinical phenotypes, regulates disease manifestations, and reshapes the tumor microenvironment. SYNE1 gene was identified as a key mediator of circadian misalignment, promoting tumorigenesis by driving epithelial-like phenotypic conversion and demonstrating therapeutic potential in colorectal cancer management. This study establishes a foundation for integrating rhythmic information into clinical practice and advances circadian biology research in the field of CRC.