Increased PAFAH1B3 was associated with poor prognosis and T-cell exhaustion microenvironment in hepatocellular carcinoma.

The link between T-cell exhaustion (TEX) and PAFAH1B3 in hepatocellular carcinoma (HCC) remains unknown, even though both of them are related to overall survival. PAFAH1B3 expression was investigated in TCGA and ICGC data, and 50 paired clinical tissue section samples were used for qRT-PCR and immunohistochemistry (IHC) confirmation. The Immunocell Abundance Identifier (ImmuCellAI) was used to precisely calculate the abundance of TEX, and its accuracy was verified by single-cell RNA-seq and labeling of CD8 + T cells in clinical tissue sections. The IMVigor 210 cohort was used to demonstrate the predictive value of PAFAH1B3 for immunotherapy efficacy. Increased PAFAH1B3 is a standalone effector of poor prognosis in HCC patients. Patients who had greater PAFAH1B3 levels had more TEX infiltration. PAFAH1B3 expression was increased in TEX in the single-cell RNA-seq data. Patients with high PAFAH1B3 expression were more likely to respond favorably to PD1/PD-L1 treatment. In conclusion, PAFAH1B3 is closely related to TEX in the tumor microenvironment (TME) and can be a useful indicator for PD1/PD-L1 therapy.