Characterization of m6A RNA methylation mediated immune heterogeneity and functional validation in hepatocellular carcinoma

Abstract

AbstractBackgroundN6‐methyladenosine (m6A) mediates RNA modification in various biological processes. It plays a key role in hepatocellular carcinoma (HCC) through regulating methyltransferase. The present study aims to analyze the correlation between the m6A and the immune status of HCC, and to construct an m6A‐related prognostic signature for HCC.MethodsHCC subtypes with different m6A modification activities were identified based on the m6A‐related genes. Lasso Cox regression was applied to construct an m6A‐related prognostic model for HCC. Then, the prognostic potential of the constructed signature was evaluated and validated in the external validation dataset. Small interfering RNAs were designed to knockdown FBXO5. CCK‐8 assay, Edu staining, wound healing assay, and Transwell cell invasion assay were used to detect cell proliferation, migration, and invasion ability.ResultsTwo m6A‐related HCC subtypes were identified. The m6A modification active group showed an immune suppressive microenvironment compared to the m6A modification inactive group. The differentially expressed genes (DEGs) between the HCC subtypes were screened. Enrichment analysis was performed using the DEGs. Subsequently, an m6A‐related prognostic model was established. The prognostic model performed well in both training and validation datasets. Moreover, knockdown of FBXO5, one of the genes in the prognostic model, inhibited the proliferation, migration, and invasion of HepG2 cells.ConclusionsThe heterogeneity of m6A RNA methylation is associated with immune status in HCC. The constructed m6A‐related gene‐based signature can predict the prognosis of HCC patients. The genes in the prognostic model also have therapeutic potential for HCC.