Overexpression of interleukin-35 in intrahepatic cholangiocarcinoma is a prognostic indicator after curative resection

Interleukin-35 (IL-35) is implicated in tumorigenesis, but its exact impact on intrahepatic cholangiocarcinoma (ICC) is not clear. The aim of the present study was to explore the specific effect of IL-35 on patient prognosis. Additionally, we formulated an effective prognostic nomogram for ICC patients after curative resection. Immunohistochemistry was applied to explore IL-35 expression as well as IL-35 receptor (IL-35R) in 102 ICC patients. Results showed that IL-35 was highly expressed in ICC tumor tissues and was positively associated with lymph node metastasis (LNM), TNM stage and vascular invasion and was an independent prognostic factor for patients' overall survival (OS) and recurrence-free survival (RFS). High expression of IL-35R (gp130 and IL-12R2) was also observed in ICC cancer tissues, but only gp130 was an independent prognostic factor for OS and RFS and was indispensable in IL-35-mediated ICC clinical prognosis. The nomogram comprising carcinoembryonic antigen, LNM, IL-35 and gp130 expression achieved better predictive accuracy compared with TNM stage for OS. Our data support that high IL-35 expression correlates with ICC aggressiveness and emerges as a valuable biomarker for evaluating ICC progression and prognosis in clinical work.