The Circadian Clock Regulates Metabolic Phenotype Rewiring Via HKDC1 and Modulates Tumor Progression and Drug Response in Colorectal Cancer

An endogenous molecular clockwork drives various cellular pathways including metabolism and the cell cycle. Its dysregulation is able to prompt pathological phenotypes including cancer. Besides dramatic metabolic alterations, cancer cells display severe changes in the clock phenotype with likely consequences in tumor progression and treatment response. In this study, we use a comprehensive systems-driven approach to investigate the effect of clock disruption on metabolic pathways and its impact on drug response in a cellular model of colon cancer progression. We identified distinctive time-related transcriptomic and metabolic features of a primary tumor and its metastatic counterpart. A mapping of the expression data to a comprehensive genome-scale reconstruction of human metabolism allowed for the in-depth functional characterization of 24 h-oscillating transcripts and pointed to a clock-driven metabolic reprogramming in tumorigenesis. In particular, we identified a set of five clock–regulated glycolysis genes, ALDH3A2, ALDOC, HKDC1, PCK2, and PDHB with differential temporal expression patterns. These findings were validated in organoids and in primary fibroblasts isolated from normal colon and colon adenocarcinoma from the same patient. We further identified a reciprocal connection of HKDC1 to the clock in the primary tumor, which is lost in the metastatic cells. Interestingly, a disruption of the core-clock gene BMAL1 impacts on HKDC1 and leads to a time-dependent rewiring of metabolism, namely an increase in glycolytic activity, as well as changes in treatment response. This work provides novel evidence regarding the complex interplay between the circadian clock and metabolic alterations in carcinogenesis and identifies new connections between both systems with pivotal roles in cancer progression and response to therapy.
Highlights • Primary and metastatic colon cancer cells from the same patient show differential time-dependent metabolic profiles. • Perturbations of the circadian clock induce differential alterations at the transcriptome level including metabolic pathways. • Core-clock gene (BMAL1) knockdown affects metabolic activity of cancer cells and impinges on treatment response. An evolutionary conserved molecular clockwork allows organisms to adapt physiology and biological processes to the geophysical time by driving various cellular pathways including metabolism and the cell cycle. In addition to dramatic metabolic alterations, cancer cells show severe changes in the biological clock likely to affect tumor progression and treatment response. Increasing efforts have been made to elucidate the connection between the circadian clock circuitry, tumor progression and cancer-associated metabolic alterations, yet a more detailed knowledge of this interplay is still missing. In this study, we investigated distinctive time-related transcriptomic and metabolic features in a cellular model of colon cancer progression and patient samples. We show that a disrupted biological clock leads to altered temporal profiles of gene expression, metabolic reprogramming and changes in drug response, and identify the hexokinase HKDC1 as a crucial element in this connection. Our results provide novel evidence regarding the complex interplay between the circadian clock and metabolic alterations in carcinogenesis and pave the way to a possible optimization of cancer treatment.