Iascone Daniel Maxim, Zhang Xue, Bafford Patricia, Mesaros Clementina, Sela Yogev, Hofbauer Samuel, Zhang Shirley L, Cook Kieona, Pivarshev Pavel, Stanger Ben Z, Anderson Stewart, Dang Chi V, Sehgal Amita
Howard Hughes Medical Institute, Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA 19104.
bioRxiv. 2023 Nov 13:2023.11.08.566310. doi: 10.1101/2023.11.08.566310.
Crosstalk between cellular metabolism and circadian rhythms is a fundamental building block of multicellular life, and disruption of this reciprocal communication could be relevant to degenerative disease, including cancer. Here, we investigated whether maintenance of circadian rhythms depends upon specific metabolic pathways, particularly in the context of cancer. We found that in adult mouse fibroblasts, ATP levels were a major contributor to overall levels of a clock gene luciferase reporter, although not necessarily to the strength of circadian cycling. In contrast, we identified significant metabolic control of circadian function in an mouse model of pancreatic adenocarcinoma. Metabolic profiling of a library of congenic tumor cell clones revealed significant differences in levels of lactate, pyruvate, ATP, and other crucial metabolites that we used to identify candidate clones with which to generate circadian reporter lines. Despite the shared genetic background of the clones, we observed diverse circadian profiles among these lines that varied with their metabolic phenotype: the most hypometabolic line had the strongest circadian rhythms while the most hypermetabolic line had the weakest rhythms. Treatment of these tumor cell lines with bezafibrate, a peroxisome proliferator-activated receptor (PPAR) agonist shown to increase OxPhos, decreased the amplitude of circadian oscillation in a subset of tumor cell lines. Strikingly, treatment with the Complex I antagonist rotenone enhanced circadian rhythms only in the tumor cell line in which glycolysis was also low, thereby establishing a hypometabolic state. We further analyzed metabolic and circadian phenotypes across a panel of human patient-derived melanoma cell lines and observed a significant negative association between metabolic activity and circadian cycling strength. Together, these findings suggest that metabolic heterogeneity in cancer directly contributes to circadian function, and that high levels of glycolysis or OxPhos independently disrupt circadian rhythms in these cells.
细胞代谢与昼夜节律之间的相互作用是多细胞生命的基本组成部分，这种相互交流的破坏可能与包括癌症在内的退行性疾病有关。在这里，我们研究了昼夜节律的维持是否依赖于特定的代谢途径，特别是在癌症背景下。我们发现，在成年小鼠成纤维细胞中，ATP水平是时钟基因荧光素酶报告基因总体水平的主要贡献者，尽管不一定是昼夜节律循环强度的主要贡献者。相比之下，我们在胰腺腺癌小鼠模型中确定了对昼夜节律功能的显著代谢控制。对一组同源肿瘤细胞克隆文库的代谢谱分析显示，乳酸、丙酮酸、ATP和其他关键代谢物水平存在显著差异，我们利用这些差异来鉴定用于生成昼夜节律报告系的候选克隆。尽管这些克隆具有共同的遗传背景，但我们观察到这些细胞系之间存在不同的昼夜节律谱，且随其代谢表型而变化：代谢最低的细胞系具有最强的昼夜节律，而代谢最高的细胞系具有最弱的节律。用苯扎贝特（一种过氧化物酶体增殖物激活受体（PPAR）激动剂，已证明可增加氧化磷酸化）处理这些肿瘤细胞系，可降低一部分肿瘤细胞系中昼夜节律振荡的幅度。令人惊讶的是，用复合物I拮抗剂鱼藤酮处理仅在糖酵解水平也较低的肿瘤细胞系中增强了昼夜节律，从而建立了一种低代谢状态。我们进一步分析了一组人类患者来源的黑色素瘤细胞系的代谢和昼夜节律表型，观察到代谢活性与昼夜节律循环强度之间存在显著的负相关。总之，这些发现表明癌症中的代谢异质性直接影响昼夜节律功能，并且高水平的糖酵解或氧化磷酸化独立地破坏这些细胞中的昼夜节律。
