Adropin promotes glycolytic reprogramming and EMT in pancreatic cancer through β₂-adrenergic receptor/β-arrestin 2/ERK signaling

Adropin, an endogenous metabolic peptide, has been implicated in pancreatic cancer (PC) progression, but the underlying mechanisms remain poorly understood. Here, we investigated the role of Adropin in PC and evaluated a β₂-adrenergic receptor (β₂-AR)-dependent β-arrestin 2/ERK signaling mechanism linking Adropin to glycolytic reprogramming and epithelial–mesenchymal transition (EMT). The expression and correlation of ENHO (encoding Adropin) and ADRB2 (encoding β₂-AR) were analyzed using public transcriptomic datasets and protein databases. In vitro experiments were performed to characterize Adropin-induced β₂-AR-associated signaling and to determine the roles of ADRB2 , ARRB2 , and glycolytic activity in Adropin-induced glycolytic reprogramming and EMT-associated phenotypes. ADRB2 and ARRB2 were depleted using shRNA, and glycolysis was inhibited using 2-deoxy-D-glucose (2-DG). The antitumor effects of Adropin knockdown combined with Barbadin treatment were further evaluated in a xenograft mouse model. Transcriptomic analyses revealed coordinated ENHO and ADRB2 expression in PC, with heterogeneous but partially concordant ENHO and ADRB2 expression patterns across pancreatic cancer datasets. Adropin induced β₂-AR phosphorylation, β-arrestin 2 recruitment, and ERK activation. These signaling events were accompanied by increased HK3 and LDHA expression, glucose uptake, lactate production, and basal extracellular acidification rate, as well as decreased E-cadherin and increased Vimentin and Snail expression, together with enhanced cell migration and invasion. ADRB2 knockdown attenuated Adropin-induced ERK activation and EMT-associated marker changes, whereas ARRB2 knockdown reduced ERK activation and the induction of HK3 and LDHA. Adropin-induced ERK activation and glycolytic responses were largely insensitive to adenylyl cyclase inhibition by SQ22536 under the tested conditions but were attenuated by Barbadin treatment. Moreover, 2-DG suppressed Adropin-induced glycolytic activation and partially reversed EMT-associated molecular changes. In xenograft models, combined Adropin knockdown and Barbadin treatment produced greater inhibition of tumor growth, glycolysis-associated alterations, and EMT-associated marker expression than either intervention alone. Our findings support a model in which Adropin promotes pancreatic cancer progression through β₂-AR-dependent β-arrestin 2/ERK signaling, with glycolytic reprogramming functionally contributing to EMT-associated molecular changes. Targeting components of this signaling axis may provide a potential therapeutic strategy for pancreatic cancer.