STMN1 expression is associated with chemotherapy and immunotherapy efficacy in biliary tract cancer

The prognostic role of STMN1 and its regulatory effects on the tumor microenvironment (TME) in biliary tract cancer (BTC) remain poorly defined. This study aimed to investigate the prognostic value of STMN1 and its predictive capacity for chemotherapy and immunotherapy responses among patients with BTC.

Six independent cohorts encompassing tissue microarray specimens and transcriptional profiling data from BTC patients were included in our analysis. STMN1 protein expression was quantified via immunohistochemistry (IHC) on tissue microarrays.

STMN1 expression was significantly correlated with inferior overall survival (OS). Multivariate regression further identified STMN1 as an independent adverse prognostic biomarker for OS. Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) revealed that elevated STMN1 expression was tightly linked to immune response activation and T-cell infiltration, enabling the formation of an immune-inflamed TME in BTC. IHC validation confirmed positive correlations between STMN1 levels and anti-tumor CD8⁺ T-cell infiltration as well as programmed death-ligand 1 (PD-L1) expression. Patients with low STMN1 expression derived prominent survival benefits from gemcitabine-based adjuvant chemotherapy (ACT), whereas high STMN1 expression predicted superior therapeutic responses to immune checkpoint blockade (ICB) in BTC recipients.

STMN1 functions as an independent prognostic biomarker and differential predictive indicator for ACT and ICB efficacy in BTC, likely facilitating the construction of an immune-inflamed TME by promoting tumor immune cell recruitment and infiltration.