Zinc finger protein 296 promotes hepatocellular carcinoma progression via intervening interaction between macrophages and B cells.

Objective: Hepatocellular carcinoma (HCC) is a prevalent malignancy with poor survival. Different cell types in the tumor microenvironment participate in the tumorigenesis and progression of HCC. This study aimed to analyze the immune microenvironment of HCC and its relationship with clinical outcomes.

Methods: We analyzed HCC RNA-seq for cell type identification and prognosis by estimating relative subsets of RNA transcripts using CIBERSORTx. The interaction between B cells and macrophages in HCC was analyzed using a Hepa1-6 orthotopic transplantation mouse model and flow cytometry. The effect of Zinc finger protein 296 (ZNF296) on the interaction of B cells and macrophages was verified using human HCC tissues analyzed through western blot, quantitative real-time polymerase chain reaction (qPCR), and multiplex immunofluorescence. A comparative analysis of immune cells associated with HCC prognosis was performed using RNA-seq data from The Cancer Genome Atlas (TCGA), bulk multimodal data, and single-cell transcriptomic data from existing HCC single-cell transcriptomic data employing the Single Cell Inferred Site Specific Omics Resource for Tumor Microenvironments (SCISSOR).

Results: Liver hepatocellular carcinoma (LIHC) RNA-seq analysis of TCGA showed that high eosinophil infiltration promoted HCC progression. The proportion of B cells correlated with that of macrophages (r=-0.24) and affected the infiltration and programmed death ligand 1 (PD-L1) expression of macrophages in HCC. ZNF296 may participate in the interaction between B cells and macrophages to accelerate the HCC progression by regulating PAFAH1B3 and H2AFX. Moreover, ZNF296 expression positively correlated with LAG3 (r=0.27) and CTLA4 (r=0.31) expression levels. Among the immune cell phenotypes related to survival and death identified by SCISSOR analysis, T cells correlated with an excellent prognosis of HCC. The normal function of liver and dendritic cells was also associated with a good prognosis in HCC.

Conclusions: This study analyzed the interaction of the immune microenvironment with HCC prognosis, identifying ZNF296 as a promising diagnostic and therapeutic target for HCC.