1. Hypoxia Stimulates PYGB Enzymatic Activity to Promote Glycogen Metabolism and Cholangiocarcinoma Progression.
- Author
-
Pan Y, Zhou Y, Shen Y, Xu L, Liu H, Zhang N, Huang T, Meng K, Liu Y, Wang L, Bai G, Chen Q, Zhu Y, Zou X, Wang S, Wang Z, and Wang L
- Subjects
- Humans, Animals, Mice, Cell Line, Tumor, Prognosis, Mice, Nude, Male, Female, Xenograft Model Antitumor Assays, Phosphoglycerate Kinase metabolism, Phosphoglycerate Kinase genetics, Mice, Inbred BALB C, Cholangiocarcinoma pathology, Cholangiocarcinoma metabolism, Cholangiocarcinoma drug therapy, Bile Duct Neoplasms pathology, Bile Duct Neoplasms metabolism, Bile Duct Neoplasms drug therapy, Glycogen metabolism, Disease Progression, Glycolysis, Cell Proliferation, Glycogen Phosphorylase, Brain Form metabolism, Glycogen Phosphorylase, Brain Form genetics
- Abstract
Cholangiocarcinoma (CCA) displays enhanced glycolysis, pivotal for fulfilling the heightened energy demands intrinsic to its malignant progression. Recent research has indicated that endogenous glycogen rather than exogenous glucose acts as the major carbon source for glycolysis, highlighting the need to better understand the regulation of glycogen homeostasis in CCA. Here, through comprehensive integrative analysis, we identified that glycogen phosphorylase brain form (PYGB), the main enzyme involved in glycogen homeostasis, was markedly upregulated in CCA tissues, serving as an independent prognostic indicator for human patients with CCA. Moreover, elevated PYGB expression potentiated cholangiocarcinogenesis and augmented CCA cell proliferation in both organoid and xenograft models. Hypoxia stimulated PYGB activity in a phosphoglycerate kinase 1-dependent manner, leading to glycogenolysis and the subsequent release of glucose-6-phosphate (G6P) and thereby facilitating aerobic glycolysis. Notably, a virtual screening pinpointed the β-blocker carvedilol as a potent pharmacologic inhibitor of PYGB that could attenuate CCA progression. Collectively, these findings position PYGB as a promising prognostic biomarker and therapeutic target for CCA. Significance: Cholangiocarcinoma cells exhibit high glycogen phosphorylase activity under hypoxic conditions that mediates metabolic reprograming to promote glycolysis and support tumor development., (©2024 American Association for Cancer Research.)
- Published
- 2024
- Full Text
- View/download PDF