CYSTM1 is a potential diagnostic and prognostic biomarker and correlated with immune infiltrates in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) remains a lethal malignancy due to the lack of reliable biomarkers for early diagnosis and prognosis. Here, we hypothesized that cysteine rich transmembrane module containing 1 (CYSTM1) could function as a potential diagnostic and prognostic biomarker and correlated with immune infiltrates in HCC. Methods: Integrating multi-omics bioinformatics analyses with experimental validation, we identified CYSTM1 as a clinically actionable biomarker. Results: We demonstrated that CYSTM1 was significantly overexpressed in HCC tissues compared to normal liver tissues. The receiver operating characteristic (ROC) curve analysis revealed that CYSTM1 had a high diagnostic value. Kaplan-Meier survival analysis indicated that high CYSTM1 expression correlated with poorer overall survival (OS). The expression level of CYSTM1 was significantly associated with the infiltration level of CD4+ T cell, macrophage and neutrophil, and immune subtypes. Experimental evidences indicated that CYSTM1 was highly expressed in HCC tissues and promoted the proliferation of HCC cells. Mechanistically, CYSTM1 might promote HCC progression through the toll-like receptor (TLR) signaling pathway. Conclusions: Collectively, our study established CYSTM1 as a dual-purpose biomarker for HCC diagnosis and prognosis, offering a therapeutic target for TLR pathway modulation. The immune-linked mechanism uncovered here addressed a critical gap in HCC personalized therapy.