RNA-seq shows Angiopoietin-like 4 promotes hepatocellular carcinoma progression by inducing M2 polarization of tumor-associated macrophages.

Abstract

Hepatocellular carcinoma (HCC) represents a particularly aggressive form of cancer, characterized by its rapid progression and a complex interplay with the surrounding immune cellular environment. The primary objective of this study was to comprehensively investigate the role of ANGPTL4 in the context of HCC, utilizing RNA sequencing (RNA-seq) techniques to explore its impact on the M2 polarization of tumor-associated macrophages (TAM) and to uncover potential mechanisms driving HCC progression. To achieve this, we performed a transcriptome analysis of HCC cell lines, alongside cells obtained after co-culturing these lines with macrophages. By comparing gene expression profiles between the experimental groups exposed to ANGPTL4 and control groups, we aimed to identify specific molecular pathways associated with ANGPTL4's function. In addition to gene expression analysis, we employed flow cytometry to assess the polarization status of TAM. Furthermore, we utilized immunohistochemistry to evaluate the distribution of macrophages within HCC tissues and to quantify the expression levels of M2 macrophage markers. The results derived from RNA-seq analysis were particularly revealing; treatment with ANGPTL4 led to a significant upregulation of genes linked to M2 polarization, notably including CD206 and Arg1. In subsequent experimental observations, it became evident that ANGPTL4 not only facilitated the M2 polarization of macrophages but also enhanced the proliferation and migratory capacity of HCC cells through the upregulation of these same cytokines.