Genetically Instrumented Circulating Metabolites and Hepatobiliary Cancer Risk: A Multi-tiered Mendelian Randomization and Functional Interrogation

Lin Tuo^1,2,3*Li Ting Yan³Ying Liu³Shu Qiang Wang³Xiang An^4*

• ¹Chongqing Medical University, Chongqing, China
• ²Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chinese Academy of Sciences, Sichuan Translational Medicine Research Hospital,, Chengdu, China
• ³Department of Infectious Disease, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
• ⁴Sichuan Academy of Medical Sciences and Sichuan People's Hospital, Chengdu, China

Hepatobiliary malignancies — including hepatocellular carcinoma and cholangiocarcinoma — are major causes of cancer-related mortality worldwide, yet their regulatory pathways remain incompletely defined. This study employed a two-sample Mendelian randomization (MR) approach to systematically investigate causal relationships between 1,400 serum metabolites and hepatobiliary cancer risk. Through stringent quality control (all SNPs with F-statistics >10) and sensitivity analyses (MR-Egger regression, weighted median method, and MR-PRESSO), we identified 10 candidate metabolites, among which meta-analysis confirmed three metabolites with robust associations: risk-increasing dimethylarginine (SDMA+ADMA) and 4-hydroxyhippurate, along with protective 3-hydroxyisobutyrate. Multivariable MR analysis validated the independent effects of 4-hydroxyhippurate and 3-hydroxyisobutyrate. In vitro functional experiments demonstrated that 4-hydroxyhippurate promoted whereas 3-hydroxyisobutyrate inhibited hepatocellular carcinoma cell proliferation. These findings advance understanding of metabolic dysregulation in hepatobiliary malignancies and nominate candidate diagnostic biomarkers and therapeutic targets, providing translationally relevant hypotheses for precision medicine.