Abstract
Hepatocellular carcinoma (HCC) has a poor prognosis, owing to its high potential for growth and metastasis. In this study, we aimed to investigate the roles of Phospholysine Phosphohistidine Inorganic Pyrophosphate Phosphatase (LHPP)in human HCCcell growth and metastasis. We analyzed the LHPP expression level in human HCC tissues paired normal tissues in the Oncomine database, and assessed the relationship between the LHPP expression levels with HCC patient's overall survival and the prognostic value of LHPP in human HCC by Kaplan-Meier survival analysis. Real-time PCR and Western Blot were used to examine the expression levels of LHPP in normal liver cell line (LO2) and human HCC cell lines (SMCC-7721, HepG2, Huh7, MHCC-97 H, and LM3). Through lentivirus infection, we established human HCC stable cell lines (Huh7 and LM3) overexpressing LHPP. Then, we detected these cell viability, colony , and invasion. Subsequently, we performed the gene set enrichment analysis (GSEA) for the RNA-seq data of HCC patients from TCGA. Finally, we examined the expression level of several oncogenes, including CCNB1, PKM2, MMP7, and MMP9, in these cells via real-time PCR assay. Here, we found thatLHPPis significantly downregulated in the human HCC tissues paired normal tissues. Furthermore, the high expression level of LHPP is associated with better clinical outcomes in human HCC. Overexpression of LHPPinhibitscell growth and metastasis in human HCC cells, and LHPP expression levels negatively correlate with cell cycle and metastasis in HCC tissues. Moreover, the level of LHPP is negatively correlated with CCNB1, PKM2, MMP7, and MMP9 in human HCC cells and HCC tissues. These findings highlight a novel tumor suppressor in human HCC growth and metastasis, and provide a promising diagnostic and prognostic factor for humanHCC.