Expression of heat shock proteins (HSP27, HSP60, HSP70, HSP90, GRP78, GRP94) in hepatitis B virus-related hepatocellular carcinomas and dysplastic nodules

AIM: Expression of heat shock proteins (HSPs) is frequently up-regulated in hepatocellular carcinoma (HCC), which evolves from dysplastic nodule (DN) and early HCC to advanced HCC. However, little is known about the differential expression of HSPs in multistep hepatocarcinogenesis. It was the purpose of this study to monitor the expression of HSPs in multistep hepatocarcinogenesis and to evaluate their prognostic significance in hepatitis B virus (HBV)related HCC.METHODS: Thirty-eight HCC and 19 DN samples were obtained from 52 hepatitis B surface antigen-positive Korean patients. Immunohistochemical and dot immunoblot analyses of HSP27, HSP60, HSP70, HSP90, glucoseregulated protein (GRP)78, and GRP94 were performed and their expression at different stages of HCC development was statistically analyzed.RESULTS: Expression of HSP27, HSP70, HSP90, GRP78, and GRP94 increased along with the stepwise progression of hepatocarcinogenesis. Strong correlation was found only in GRP78 (Spearman's r= 0.802). There was a positive correlation between the expressions of GRP78, GRP94, HSP90, or HSP70 and prognostic factors of HCC. Specifically, the expression of GRP78, GRP94, or HSP90 was associated significantly with vascular invasion and intrahepatic metastasis.CONCLUSION: The expressions of HSPs are commonly up-regulated in HBV-related HCCs and GRP78 might play an important role in the stepwise progression of HBVrelated hepatocarcinogenesis. GRP78, GRP94, and HSP90 may be important prognostic markers of HBV-related HCC, strongly suggesting vascular invasion and intrahepatic metastasis.

Hepatic preconditioning of doxorubicin in stop-flow chemotherapy:NF-κB/IκB-α pathway and expression of HSP72

AIM: To provide hepatic protection through administration of doxorubicin before stop-flow chemotherapy (SFC) and to investigate the expression of heat shock protein 72(HSP72) and role of nuclear factor kappa B (NF-kB) in this effect.METHODS: The hepatic preconditioning of doxorubicin was established in a porcine model by injection of doxorubidn(1 mg/kg) before SFC. The experimental animals were randomized into two groups: groups receiving doxorubicin(DOX) and normal saline (NS). Serial serum and tissue samples were taken from both groups to evaluate the protection of doxorubicin. Western blot and immunoprecipitation were applied to detect the expression of HSP72, NF-kB p65 protein, inhibitor kB-α (IkB-α) and phosphorylated IkB-α as well. The expression of tumor necrosis factor α (TNF-α) was estimated by semiquantitative RT-PCR. And the extent of the hepatic injury was estimated with the level of serum aminotransferases.RESULTS: An abundance production of HSP72 in porcine liver was observed after 24 h of intravenous administration of doxorubicin, but without any change in the expression of NF-kB p65 subunit in cytoplasm. NF-kB p65 subunit accumulated in nuclei at the end of SFC and reached its highest level at 30 rain after the restoration of the abdominal circulation and decreased gradually during the 6 h after SFC in NS group, while there was little change in DOX group. There was also a slight decrease of IkB-α at 30 min after the restoration of the abdominal circulation in NS group accompanying with the appearance of phosphorylated IkB-α. The expression of TNF-α was significantly higher in NS group than that in DOX group (average 1.40±0.17 vs 0.62±0.22, P<0.01) at serial time points after SFC. Serum ALT and AST levels of NS group were higher after 24 h than those of DOX group (93.2±7.8 IU/L vs 53.34±13.9 IU/L,217.0±29.4 IU/L vs 155.0±15.6 IU/L for ALT and AST respectively, P<0.05) and alter 48 h than those of DOX group (66.6±18.1 IU/L vs 43.3±16.7 IU/L, 174.4±21.3 IU/Lvs 125.7±10.5 IU/L for ALT and AST respectively, P<0.05).CONCLUSION: Doxorubicin renders the liver to be tolerant to the hepatic influence in SFC in a porcine model through the NF-kB/IkB-α pathway with the expression of HSP72.