PRC1 promotes GLI1-dependent osteopontin expression in association with the Wnt/β-catenin signaling pathway and aggravates liver fibrosis

Background: PRC1 (Protein regulator of cytokinesis 1) regulates microtubules organization and functions as a novel regulator in Wnt/beta-catenin signaling pathway. Wnt/beta-catenin is involved in development of liver fibrosis (LF). We aim to investigate effect and mechanism of PRC1 on liver fibrosis. Methods: Carbon tetrachloride (CCl4)-induced mice LF model was established and in vitro cell model for LF was induced by mice primary hepatic stellate cell (HSC) under glucose treatment. The expression of PRC1 in mice and cell LF models was examined by qRT-PCR (quantitative real-time polymerase chain reaction), western blot and immunohistochemistry. MTT assay was used to detect cell viability, and western blot to determine the underlying mechanism. The effect of PRC1 on liver pathology was examined via measurement of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and hydroxyproline, as well as histopathological analysis. Results: PRC1 was up-regulated in CCl4-induced mice LF model and activated HSC. Knockdown of PRC1 inhibited cell viability and promoted cell apoptosis of activated HSC. PRC1 expression was regulated by Wnt3a signaling, and PRC1 could regulate downstream beta-catenin activation. Moreover, PRC1 could activate glioma-associated oncogene homolog 1 (GLI1)-dependent osteopontin expression to participate in LF. Adenovirus-mediated knockdown of PRC1 in liver attenuated LF and reduced collagen deposition. Conclusions: PRC1 aggravated LF through regulating Wnt/beta-catenin mediated GLI1-dependent osteopontin expression, providing a new potential therapeutic target for LF treatment.