| BackgroundHepatocellular carcinoma(HCC)is the fourth leading cause of cancer-related death and is on the increase worldwide.Studies have found that galactose-3-O-sulfonyltransferase-1(GAL3ST1)is associated with the occurrence of primary clear cell renal cell carcinoma.However,the functions and mechanism of GAL3ST1 in the progression of HCC are still unclear.GAL3ST1 may be a therapeutic and research target for HCC.ObjectiveThe study was aimed to investigate the function and mechanism of GAL3ST1 in the progression of HCC.Methods(1)The GAL3ST1 expression in human normal tissues was analyzed using the online databases of BioGPS,GTEx,Consensus,HPA,and FANtom5.CCLE,Firebrowse,GEPIA,TCGA,and gene radar maps were used to retrieve the GAL3ST1 expression in different liver cancer tissues.(2)The GAL3ST1 expression differences in human normal tissues and HCC tissues were analyzed using the online databases of TCGA,GSE14520,and Wurmbach databases.GSE14520 and GEPIA databases were used to detect the relationship between GAL3ST1 and the prognosis of HCC.The pathological correlation between GAL3ST1 and HCC was determined in the GSE 14520 database.The relationship between GAL3ST1 and the pathological grade of HCC was analyzed in GEPIA.(3)String,IID,and gene radar databases were used to search the protein interaction relationship of GAL3ST1.String and Reactome databases were used to search the enrichment pathway of GAL3ST1.The correlation between GAL3ST1 and UGT8/GALC/SPHK1 was detected in GEPIA and CCLE databases.(4)To study the function of GAL3ST1 in the progression of HCC,the CCLE and HPA databases were used to identify high GAL3ST1 expression in liver cancer cell lines.The overexpression and knock-down of GAL3ST1 in MHCC97H were constructed by lentivirus,then,the expression of GAL3ST1 was detected by Western blot and qRT-PCR.The proliferation of MHCC97H in the GAL3ST1 overexpression and knockdown groups was detected by MTT.Flow cytometry and western blot assay were used to detect the cell cycle,proliferation-related protein,and apoptosis protein expression.Western blot was used to detect the expression of UGT8,GALC,and SPHK1.(5)A patient-derived tumor xenograft(PDX)model was designed to verify the effect of GAL3ST1 on the progression of HCC.qRT-PCR was used to detect the levels of UGT8,GALC,and SPHK1 mRNA.Results(1)The combined database found that GAL3ST1 mRNA is highly expressed in the spinal cord and kidney.CCLE,Firebrowse,GEPIA,TCGA,and gene radar maps found that GAL3ST1 mRNA is highly expressed in kidney renal clear cell carcinoma(KIRC).(2)TCGA,GSE14520,and Wurmbach database found that GAL3ST1 is highly expressed in human liver cancer tissues.The HCC patients with high GAL3ST1 expression have a poorer 5-year prognosis,and patients with low expression have a better 5-year prognosis.The TNM severity level and serum AFP levels were increased in HCC patients with highly GAL3ST1 expression.GAL3ST1 levels gradually increased in stages Ⅰ to Ⅳ(cancer stages).(3)Protein-protein interaction proved that GAL3ST1 has a potential interaction with UGT8/GALC/SPHK1.GAL3ST1 is mainly involved in the sphingomyelin metabolism signaling pathway.GEPIA and CCLE databases found that GAL3ST1 is positively correlated with UGT8/GALC/SPHK1 expression.(4)CCLE and HPA databases found that GAL3ST1 is the highest expression in MHCC97H cells.MTT results showed that GAL3ST1 overexpression promotes the proliferation of MHCC97H.GAL3ST1 acts on cell cycle at the S phase and promotes the Ki-67 and PCNA proliferation-related proteins expression.GAL3ST1 overexpression inhibits MHCC97H apoptosis,promotes Bcl-2 expression,and reduces Bax expression.In addition,GAL3ST1 overexpression promotes the UGT8,GALC,and SPHK1 protein expression.(5)GAL3ST1 promotes the progression of liver cancer in the PDX model.qRT-PCR results found that GAL3ST1 increases the mRNA levels of UGT8,GALC,and SPHK1.ConclusionGAL3ST1 regulates the progression of HCC by participating in the sphingomyelin metabolic pathway.This study provides theoretical guidance for exploring new treatment methods for HCC patients. |
