Overexpression of AGR2vH, an oncogenic AGR2 spliced transcript, potentiates tumorigenicity and proteomic alterations in cholangiocarcinoma cell.

The upregulation of anterior gradient 2 (AGR2) has been observed in cholangiocarcinoma (CCA) cells, nras-mutant zebrafish, and specimens derived from CCA patients. Our previous study reported AGR2 splicing into AGR2vH to facilitate CCA cell aggressiveness, while this work aims to investigate the molecular mechanisms underlying AGR2vH. First, AGR2vH upregulation was demonstrated in CCA tissues derived from patients. For in vitro studies, established AGR2vH-overexpressing KKU-213A cells were found to exhibit increased proliferation and clonogenicity. In vivo tumorigenicity assessed in a mouse model represented higher tumorigenic potential in AGR2vH-overexpressing cell xenograft mice. Next, LC-MS/MS was analyzed, indicating that AGR2vH may be associated with CCA cell proliferation via Wnt/β-catenin signaling pathway activation, which was verified by β-catenin expression and nuclear translocation. The current results provide evidence that AGR2vH upregulation promotes tumorigenicity in CCA cells linked with an alteration of CCA cell proteome.