Abstract
The crosstalk between cancer cells and tumor microenvironment plays critical roles in hepatocellular carcinoma (HCC). The identification of long non-coding RNAs (lncRNAs) mediating the crosstalk might promote the development of new therapeutic strategies against HCC. Here, we identified a lncRNA, HOMER3-AS1, which is over-expressed in HCC and correlated with poor survival of HCC patients. HOMER3-AS1 promoted HCC cellular proliferation, migration, and invasion, and reduced HCC cellular apoptosis. Furthermore, HOMER3-AS1 promoted macrophages recruitment and M2-like polarization. In vivo, HOMER3-AS1 significantly facilitated HCC progression. Mechanism investigations revealed that HOMER3-AS1 activated Wnt/β-catenin signaling via upregulating HOMER3. Functional rescue experiments revealed that HOMER3/Wnt/β-catenin axis mediated the roles of HOMER3-AS1 in promoting HCC cellular malignant phenotypes. Furthermore, colony stimulating factor-1 (CSF-1) was also identified as a critical downstream target of HOMER3-AS1. HOMER3-AS1 increased CSF-1 expression and secretion. Blocking CSF-1 reversed the roles of HOMER3-AS1 in inducing macrophages recruitment and M2 polarization. Furthermore, positive correlations between HOMER3-AS1 and HOMER3 expression, HOMER3-AS1 and CSF-1 expression, and HOMER3-AS1 expression and M2-like macrophages infiltration were found in human HCC tissues. In summary, our findings demonstrated that HOMER3-AS1 drives HCC progression via modulating the behaviors of both tumor cells and macrophages, which are dependent on the activation of HOMER3/Wnt/β-catenin axis and CSF-1, respectively. HOMER3-AS1 might be a promising prognostic and therapeutic target for HCC.