Mechanism Research Of SQLE Inhibitors For Hepatocellular Carcinoma Treatment

Hepatocellular carcinoma(HCC)is one of most common malignant tumors,more than 500000 new cases occur every year.85% cases are in developing countries where high incidence of hepatocellular carcinoma in hepatitis B virus infection epidemic area,and our country is hepatitis B virus infection superpower.Surgical treatment is considered to be the best treatment,but only about 10-20% of patients have a chance to received a liver transplant and radical surgery.In patients underwent liver resection in 5 years of survival rate is about 50%,the recurrence rate as high as 70%.Even early stage of liver cancer TNM and BCLC stage still prognostic is difference.Therefore,looking for early prognostic indicators and potential targets for drug treatment can guide individualized treatment intervention with poor prognosis better,to improve the patients survival rate and reduce the recurrence rate of liver cancer with great significance.Previous research found that the gene chip confirmed squalene epoxidase(SQLE)expression in the cancer tissue is about 6.2 times than adjacent tissue.Tissue microarray analysis was found that the expression level of SQLE had relation to capsular integrity(P = 0.021),number of tumors(P = 0.010),MVI(P < 0.001).Multiple factors analysis shows that SQLE was independent risk factor of postoperative recurrence and survival.Cell experiment on SQLE reduction and overexpression effect hepatic carcinoma cell proliferation and invasive ability.Lung squamous carcinoma,breast cancer,colon cancer,hepatic carcinoma,prostate cancer have SQLE in expression differences are closely related to the prognosis.In pancreatic cancer,radiation resistance was caused by SQLE high expression.Comprehensive these studies,we choose SQLE as an observation index to study the possible role in the tumor proliferation and metastasis.SQLE is considered beyond 3-hydroxy-3-methyl glutaric acyl coenzyme A reductase(HMG CoA reductase)another key enzyme in sterol metabolic pathway.Considering the abnormal cholesterol metabolism pathway is closely related to tumorigenesis,we speculate SQLE maybe have certain biological significance in the occurrence and development of hepatic carcinoma.This topic discuss NB–598 one of the most efficient SQLE inhibitors can effect tumor cytology and its possible mechanism in hepatocellular carcinoma cell experiment and animal experiment.This topic from the following two aspects: 1.SQLE in hepatocellular carcinoma(HCC)expression and tumor suppress effect of NB-598.2.Through TCGA public database for breast cancer,colon cancer,bile duct cancer,hepatocellular carcinoma,adenocarcinoma,squamous carcinoma of sterol genes enrichment degree of bioinformatics analysis.Part 1 Expression of SQLE in patients with HCC and tumor suppress effect of NB-598Purpose: To investigate SQLE in patients with hepatic carcinoma tissues expression level and tumor suppress effect of NB-598.Methods: 20 cases of liver cancer tissue and adjacent tissue samples were analysised by RT-PCR,Western blotting and immunohistochemical,to study SQLE differences between liver cancer tissues and adjacent tissues in expression level.Cell experiment: CCK8 resistance experiment,growth experiment,cell cycle experiment.Animal experiment: drug efficacy and safety experiment in rats,effect of drug in tumor nude mice.Results: 20 cases of liver cancer tissue and adjacent tissue samples analysised by RT-PCR,Western blotting and immunohistochemical show that SQLE in part of the liver cancer samples increased,SQLE in hepatocellular carcinoma cell lines are higher expression than normal liver cell lines.SQLE in normal mice liver is low expression,high expression in mice with liver tumor near blood vessel area.Drug resistance and growth curve found that SQLE inhibitor NB-598 in LPDS medium have good killing and inhibiting effects in 7404,HepG2,7919 cell lines.Cell cycle experiments suggest LPDS medium after addition NB-598 in 7404,G1 and G2 cells are more,G2 cells rise in HepG2 cell line.animal experiment preliminary embodies the NB-598 as the efficacy of lipid-lowering drugs,also has certain ablity inhibit tumorigenesis.Part 2 Concentration degree analysis of cholesterol genes in tumorsPurpose: Explore the cholesterol metabolism pathway significances in breast cancer,colon cancer,bile duct cancer,hepatocellular carcinoma,adenocarcinoma,and squamous carcinoma.Methods: Look through TCGA public database for bioinformatic analysis sterol genes enrichment degre in breast cancer,colon cancer,bile duct cancer,hepatocellular carcinoma,lung adenocarcinoma,lung squamous carcinoma.Results: 1.In squamous carcinoma sterol genetic connection degree declines,core and sterols genes tend to repel.Cholesterol metabolism pathway maybe play lesser important in the tumor,but it is likely to affect the tumor cell DNA replication and the ribosome's translation action,in turn,affects the prognosis of patients.2.Bile duct carcinoma,breast cancer,sterol genetic connection degree rise,core and sterol genes have a fusion tendency,prompt importance in cholesterol metabolism pathways in cancer,sterol genes group may play a more central role in tumorigenesis.In breast cancer,it may affect the tumor angiogenesis through sticky spot.In bile duct cancer,cholesterol genes group may affect tumor metabolic pathways by producing small molecule metabolites.3.Cholesterol genes without connection degree change tendency in hepatic carcinoma,cholesterol metabolism pathway importance is not clear;4.Colon and lung adenocarcinoma have tend to change of sterol genetic connection degree,but the important of cholesterol metabolism pathway in these tumors are unclear.Sterol genes in lung adenocarcinoma may paly a role in immune response,in turn,affects the prognosis of patients.All conclusion:1.There are differences SQLE expression between the carcinoma than adjacent tissues in hepatocellular carcinoma(HCC)patients.2.LPDS medium with NB-598 inhibit SQLE enzyme activity,by reducing the intracellular cholesterol levels make the cell cycle G2 block to damage and inhibit the growth of hepatocellular carcinoma cells.3.The preliminary animal experiments confirmed that the NB-598 as the efficacy of lipid-lowering drugs,also has certain anti-tumor effect.4.Bioinformatics analysis sterol genes group SQLE represented in the occurrence and development of hepatocellular carcinoma have non-core functions.Imply abnormal cholesterol metabolism may plays an important role in the development of hepatocellular carcinoma with background of hepatitis B infection.Above all: SQLE not only can be used as the prognosis of liver index,we have reason to believe that limit tumor cells intracellular cholesterol levels may affect the tumorigenic,and SQLE as the key enzyme in cholesterol synthesis,is expected to become the new target for the treatment of hepatocellular carcinoma.SQLE inhibitors antitumor function is thought to regulate cholesterol levels or affecting the signal transduction of tumor cells,its specific mechanism still need further research.