Hsa_circ_0006232 promotes laryngeal squamous cell cancer progression through FUS-mediated EZH2 stabilization

Laryngeal squamous cell cancer (LSCC) is one of the most common malignant tumors in head and neck tumors. Our previous study has revealed that hsa_circ_0006232 is abnormally expressed in LSCC. This study attempts to verify the biological role of hsa_circ_0006232 in LSCC. We found that compared with human bronchial epithelial cells, hsa_circ_0006232 was highly expressed in human LSCC cells (AMC-HN-8 and TU686). Moreover, hsa_circ_0006232 promoted proliferation, migration and invasion of AMC-HN-8 and TU686 cells. Hsa_circ_0006232 promoted the expression of enhancer of zeste homolog 2 (EZH2) and repressed the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Fused in sarcoma (FUS) interacted with hsa_circ_0006232 and EZH2, and FUS promoted the stabilization of EZH2. Hsa_circ_0006232 inhibited PTEN by promoting FUS expression. Moreover, we constructed a tumor xenograft model by injection of AMC-HN-8 cells with hsa_circ_0006232 knockdown, and we found that hsa_circ_0006232 deficiency decreased tumor growth in mice. Hsa_circ_0006232 silencing repressed EZH2 expression and enhanced PTEN expression in tumor tissues. In conclusion, our data have demonstrated that Hsa_circ_0006232 promotes proliferation, migration and invasion of LSCC cells, and accelerates tumor growth of LSCC through FUS-mediated EZH2 stabilization. Thus, hsa_circ_0006232 may be a novel therapeutic target in LSCC treatment.