Higher content of microcystin‐leucine‐arginine promotes the survival of intrahepatic cholangiocarcinoma cells via regulating SET resulting in the poorer prognosis of patients

Background & aims Intrahepatic cholangiocarcinoma (ICC) has over the last 10 years become the focus of increasing concern largely due to its rising incidence and high mortality rates worldwide. Microcystin-leucine-arginine (MC-LR) has been reported to be carcinogenic, but there are no data on the linkage between MC-LR and ICC. This study aimed to explore whether the content levels of MC-LR in the tumour tissues of ICC patients be associated with the prognosis and if so, to characterize the mechanism in ICC cells. Methods We conducted a retrospective study to evaluate the prognostic value of MC-LR in ICC after resection. All patients were divided into two groups according to the content of MC-LR in tumour via immunohistochemistry: low-MC-LR group (n = 28) and high-MC-LR group (n = 30). Results Multivariate analysis showed high-MC-LR level was the prognostic factor for OS and RFS after hepatectomy (P = .011 and .044). We demonstrated that MC-LR could promote the survival of human ICC cell lines and SET was identified as an important mRNA in the progression via RNA array. Conclusions We provide evidence that MC-LR was an independent prognostic factor for ICC in humans by modulating the expression of SET in human ICC cells.