Pachymaran regulates pyroptosis of liver cancer cells via SQLE/NLRP3/GSDMD signaling pathway / 中国病理生理杂志

ABSTRACT

AIM:Using bioinformatics analysis and experiment validation to explore the differential expres-sion genes related to abnormal lipid metabolism in hepatocellular carcinoma(HCC)and the molecular mechanism of pachymaran affecting pyroptosis through squalene epoxidase(SQLE)/nucleotide-binding oligomerization domain-like re-ceptor protein 3(NLRP3)/gasdermin D(GSDMD)signaling pathway.METHODS:(1)The GEO,GSEA,DAVID,STRING and GEPIA databases were employed to screen abnormal lipid metabolism-related differentially expressed genes in HCC.(2)The tumor tissues from HCC patients(n=9)were collected to verify the differential expression of SQLE.(3)The inhibitory effect of pachymaran on the viability of human HCC cell line HepG2 was measured by CCK-8 assay.(4)The HepG2 cells were divided into control group and pachymaran(800 mg/L)group.The cell migration was analyzed by wound-healing assay,and RT-qPCR was used to measure SQLE mRNA expression.(5)The HepG2 cells with overexpres-sion of SQLE(OE-SQLE)were divided into 5 groups as follows:control group,overexpression negative control(OE-NC)group,OE-SQLE group,OE-NC+pachymaran group,and OE-SQLE+pachymaran group.The mRNA and protein expres-sion levels of SQLE and pyroptosis-related factors were determined by RT-qPCR and Western blot.Colorimetric method and ELISA were used to measure lactate dehydrogenase(LDH),interleukin-1β(IL-1β)and IL-18 levels.The necrosis of HepG2 cells was analyzed by flow cytometry.RESULTS:The SQLE gene was screened through bioinformatics analysis,and its mRNA expression was significantly increased in tumor tissues from HCC patients(P＜0.01).In cell experiments,treatment with 800 mg/L pachymaran for 48 h had a significant inhibitory effect on HepG2 cell viability,and the expres-sion of SQLE mRNA was reduced(P＜0.01).After overexpression of SQLE,the mRNA and protein levels of pyroptosis-re-lated factors,necrotic rate,and LDH,IL-1β and IL-18 levels were significantly decreased(P＜0.05).After treatment with pachymaran,the above indicators were significantly increased(P＜0.05).CONCLUSION:The SQLE is abnormal-ly highly expressed in HCC,and pachymaran can affect the growth of HCC cells by activating the NLRP3/GSDMD pyropto-sis pathway through SQLE.