Study Of Anti-HBV Drug Focusing On The Heat Shock Protein As The Target

Hepatitis B virus(HBV) is a small DNA virus which replicates through reverse transcription, it can cause hepatitis B disease by infecting host hepatocytes. HBV infection is a worldwide public health problem, chronic infection can lead to liver fibrosis, liver cirrhosis and liver cancer. Currently, the clinical treatments of chronic hepatitis B there have two main ways: interferon alpha and nucleos(t)ide analogues such as entecavir, lamivudine and adefovir. However, the both treatments exist obvious shortages, such as high dose interferon alpha has limited response rates(ca. 33%) and severe adverse effects, nucleos(t)ide analogues have a high rate of drug resistance.Thus, novel anti-HBV reagents are needed.Heat shock proteins(HSPs) is one of the types of chaperones that expressed by cells under stress, they are necessary for the interaction of the reverse transcriptase(P protein) and the RNA packaging signal(?) interaction during the process of HBV replication. KNK437 can suppress the transcription of HSPs mRNA and translation of HSPs protein by modulating the heat shock factor(HSF) and heat shock element(HSE), it also can affect physiological function of heat shock protein in HeLa, colon cancer, squamous cell carcinoma and the cultivation of glioblastoma cells under the conditions of heating treatment. And KNK437 also inhibited the production of virus particles in the baculovirus infection cycle. But the role of KNK437 on the replication of the hepatitis B virus is still unknown.This study mainly use three kinds of liver cancer cell line model, HepG2.2.15 cell lines, Huh7 cells transiently transfected with 1.1×HBV(pCH9-3091) plasmid and Huh7 cells transiently transfected with 1.3×HBV(pGEM- 1.3×HBV) plasmid. Having given these cells appropriate stimulation of KNK437, with CCK-8 method determined the cytotoxic drugs, enzyme-linked immune method to detect the HBsAg and the HBeAg secretion, fluorescence quantitative PCR method to detect the level of HBV DNA and RNA in the cell, finally also tested the KNK437 effects on heat shock proteins. Our results showed that 20?M KNK437 had no toxicity to cells, and it inhibited the secretion of HBsAg and HBeAg, and down-regulated the level of HBV DNAs and RNAs in the cells, inhibit HBV replication and transcription, the experiments also showed that KNK437 inhibited the expression of heat shock protein. Thus, the present study clearly proves that KNK437 suppresses HBV replication and transcription, as well as the expression of antigen proteins in hepatoma cell models.While the long-term administration of nucleos(t)ide analogues attacking to the viral polymerase leads to easily the assistence of drugs in the patients, the target of KNK437 is not the virus itself. So, it may be developed into a potential anti-HBV option.