Association of transforming growth factor-b1 gene polymorphisms with a hepatocellular carcinoma risk in patients with chronic hepatitis B virus infection

Transforming growth factor-b1 (TGF-beta 1) can act as both a tumor suppressor and a stimulator of tumor progression. We have examined the relationship between polymorphisms of the TGF-beta 1 gene and the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV) infection. A total of 1,237 Korean subjects were prospectively enrolled; 1,046 patients with chronic HBV infection and 191 healthy controls with no evidence of recent or remote HBV infection. The patients were divided into two groups: those without (n=809) and those with HCC (n=237). Single nucleotide polymorphisms (SNPs) of TGF-beta 1 were searched for and genotyped using the single base extension method. In Korean subjects, only two SNPs were found among the seven known polymorphisms of TGF-beta 1, at position -509 and in codon 10. The risk of HCC was significantly lower in patients with the T/T or C/T genotypes than in those with the C/C genotypes at position -509 (PT; L10P] conferred a decreased likelihood of HCC (OR=0.74; 95% CI, 0.59-0.93; P=0.008). In conclusion, the presence of the TGF-beta 1 -509C>T promoter or of the L10P polymorphism, and the combination of both [-509C>T; L10P] as a haplotype were strongly associated with a reduced risk of HCC in patients with chronic HBV infection.

The Effect of Dehydroepiandrosterone on Inhibition of Carcinogenesis and Induction of Apoptosis in Murine Hepatoma Model

Tumor suppressive effect of dehydroepiandrosterone (DHEA) on the experimentally induced hepatocellular carcinoma was investigated, especially focusing on glutatione transferase and transglutaminase with aptosis in the carcinogenesis. The chemical hepatocarcinogenic procedure of Solt-Farber method was used on Sprague-Dawley rats. Experimental groups were divided into AA group treated by the standard Solt-Farber regimen of diethylnitrosamine (DEN) and 2-acetamidofluorene (AAF) and AD group treated with DHEA simultaneously with AAF and the AAD group treated by DHEA after treatment with AAF. Each group was divided by time sequence further into four subgroups, GI (8wk), G2 (16wk), G3 (28wk), and G4 (36wk). For neoplastic lesion, the immuno histochemical study with anti GSTP antibody was carried out, while the activity and expression of TGase was compared at the same time. The results were summarized as follows; GST-P positive foci detected in AD groups were significantly more suppressed by DHEA treatment than AA groups (P<0.05). AD groups. AD group showed higher activities of TGase than AA groups (P<0.05), which was confirmed by Western and Northern blot analysis. But the number of apoptotic bodies was not correlated with activity and expression of TGase in the nodule. These results suggest that the suppressive effect of DHEA on the murine hepatocellular carcinogenesis might be operating on the promotion process of carcinogenesis rather than regression process of transformed hyperplastic nodules.