Exosomal IGFALS as a prognostic biomarker in hepatocellular Carcinoma: Associations with immune infiltration and clinical outcomes.

[PURPOSE] This investigation seeks to examine the relationship between exosomal Insulin-like Growth Factor Binding Protein Acid Labile Subunit (IGFALS) gene expression, immune infiltration, and clinical outcomes in individuals with hepatocellular carcinoma (HCC).

[METHOD] Clinical data and IGFALS expression levels were obtained from the TCGA and GEO databases. Immunohistochemistry was performed to confirm IGFALS expression in both HCC and adjacent non-tumor tissues. To validate survival analyses, restricted cubic spline models were used to explore associations between overall survival (OS) and the expression of IGFALS in liver hepatocellular carcinoma (LIHC). Gene set enrichment analysis (GSEA) identified IGFALS-associated pathways, while Gene set enrichment analysis (ssGSEA) evaluated IGFALS-immune cell infiltration correlations. Functional characterization included proliferation, migration/invasion, molecular profiling, and apoptosis assays.

[RESULT] Compared to normal tissues, IGFALS expression levels were notably decreased in tumor tissues. A notable link was detected between IGFALS expression and multiple clinical factors, including gender, weight, residual tumor, adjacent hepatic tissue inflammation, vascular invasion, AFP, BCLC, tumor size, multinodular, TACE, and satellite lesion in HCC. Reduced IGFALS expression in HCC was correlated with decreased OS. Moreover, the IGFALS level in malignant tumor cells post-immunotherapy was observed to be markedly higher than that in the pre-treatment phase. A strong association between IGFALS and immune infiltration levels was also established. At the same time, in vitro experiments also verified the function of the IGFALS gene.

[CONCLUSION] The exosomal IGFALS gene holds potential as a prospective indicator for assessing the outcome of individuals with HCC.