The activity of interferon (IFN) is not elucidated from the viewpoint of cancer prevention in chronic hepatitis C patients en masse. The hepatocellular carcinogenesis rate was analyzed statistically in 1,643 patients with chronic hepatitis C: 1,191 patients with IFN therapy and 452 without IFN therapy. Hepatocellular carcinogenesis rates in the treated and untreated groups were 2.1% and 4.8% at the end of the 5th year, and 7.6% and 12.4% at the 10th year, respectively (P ‫؍‬ .0036). Multivariate analysis showed that IFN slightly decreased the risk of carcinogenesis by 33%, compared with that of untreated patients (P ‫؍‬ .14), adjusting for the confounding effects of age, fibrotic stage, gender, and ␥-glutamyl transpeptidase (GGTP) value. Until recently, hepatitis C virus (HCV) has been reported to be a causative agent of hepatocellular carcinoma (HCC) aside from hepatitis B virus. [1][2][3][4] In two cohort studies from Tokyo 5 and Osaka 6 of Japanese patients with cirrhosis, the cumulative appearance rates of HCC at 3, 5, 10, and 15 years were respectively, 12.5%, 19.4%, 44.3%, and 58.2%. HCC occurred more frequently (75.2% at 15 years) in those patients with only HCV antibodies at enrollment than in those with only hepatitis B surface antigen (27.2%). According to our estimation of the carcinogenesis rates in untreated patients with chronic hepatitis C, 7 5-year, 10-year, and 15-year rates were 4.8%, 13.6%, and 26.0%, respectively. Because life expectancy of patients with HCV-related cirrhosis is largely influenced by development of HCC in the clinical course, and because an effective and truly curative therapy for HCC still remains limited at best, primary prevention of HCC in patients with chronic liver disease is of great importance.Interferon (IFN) is effective in eliminating HCV and in reducing serum alanine transaminase (ALT) in some patients with chronic hepatitis C. [8][9][10][11] The response to IFN therapy is related to factors including HCV subtype, serum concentration of HCV, IFN treatment schedule, and liver histology. 11-14 A Japanese trial of IFN for patients with HCV-related cirrhosis showed that IFN therapy decreased the HCC appearance rate through the disappearance of HCV RNA. 15 However, there has been no report about the anticarcinogenic activity of IFN in patients with chronic hepatitis type C, comparing a large number of untreated patients. To elucidate whether IFN suppresses the carcinogenesis rate in patients with chronic hepatitis C, we studied a total of 1,191 patients with IFN therapy compared with 452 patients without treatment, adjusting background features using multivariate analysis. One of the principal aims of our study was therefore to show a role of IFN in cancer prevention in chronic hepatitis type C en masse: To what extent could IFN decrease the carcinogenesis rate from chronic hepatitis C in society? The other aim was to assess a possible mechanism, if any, of cancer prevention by IFN. PATIENTS AND METHODSStudy Population. A total of 1,643 patients with chronic hepatitis ...

Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However, the emergence of lamivudine-resistant mutant virus, with amino acid substitution in the YMDD motif of DNA polymerase, has been reported. We report the emergence and takeover of YMDD mutant and re-takeover by wild type during and after long-term lamivudine therapy. YMDD mutants were detected in five patients who showed DNA breakthrough (HBV DNA becoming detectable after a period of DNA negativity), which occurred after 9 to 14 months of lamivudine therapy. Four of five mutants had amino acid sequence YIDD, and the remaining mutant had YVDD. Patients with high HBV-DNA titer and/or hepatitis B e antigen tended to develop breakthrough (P ‫؍‬ .038). Using a sensitive and specific polymerase chain reaction (PCR)-based method developed in this study, the emergence of YMDD mutants was detected 1 to 4 months before DNA breakthrough, but not detected in any of the pretreatment sera. The mutants were predominant at breakthrough, but were replaced by wild-type virus 3 to 4 months after cessation of therapy in the two patients who discontinued therapy. One of these patients had a relapse of hepatitis. Mutant continued to replicate in the remaining three patients who continued to receive treatment, and relapse occurred in only one of these patients. Our results suggest that the replication of YMDD mutant viruses is less than wild type and is re-overtaken by wild type after cessation of therapy. Re-administration of lamivudine, possibly combined with other antiviral therapy, might be useful in some patients experiencing hepatitis with lamivudine-resistant variants. (HEPATOLOGY 1998;27: 1711-1716.)is a potent inhibitor of RNA-dependent DNA polymerase of hepatitis B virus (HBV), as well as human immunodeficiency virus (HIV) reverse transcriptase. [1][2][3][4][5][6][7][8][9][10] The in vivo antiviral activity of lamivudine has been reported in animal studies as well as in humans. [11][12][13][14][15][16][17][18][19][20][21][22] However, the emergence of lamivudineresistant HBV strains was initially noticed in patients who received orthotopic liver transplantation and immunosuppressive therapy. [23][24][25][26][27][28] Such resistant viruses show a characteristic mutation of the 550th amino acid methionine in the YMDD motif of DNA polymerase to isoleucine (YIDD mutant) or valine (YVDD mutant). Honkoop et al. 29 recently showed the emergence of such mutant viruses in 5 of 14 (36%) immunocompetent patients who were treated with lamivudine over 26 weeks. However, in a larger placebo-controlled study in 358 Asian patients with HBV infection treated for 52 weeks, the rate of detection of lamivudine-resistant variants by polymerase chain reaction (PCR) was 19 of 134 (14%) in patients treated with 100 mg daily. 30 To our knowledge, there is no report that describes the presence of mutant viruses in the serum before administration of lamivudine. The low incidence and late emergence of YM...

The AT1 receptor antagonist telmisartan ameliorated renal fibrosis after UUO by inhibition of oxidative stress, even under acatalasemic conditions.

These findings indicate that acatalasemia exacerbates renal oxidant tissue injury and sensitizes remnant kidneys to EMT and progressive renal fibrosis. This study suggests a central role for catalase in the defense against oxidant-mediated renal fibrosis.

Tissue homeostasis is determined by the balance between oxidants and antioxidants. Catalase is an important antioxidant enzyme regulating the level of intracellular hydrogen peroxide and hydroxyl radicals. The effect of catalase deficiency on renal tubulointerstitial injury induced by unilateral ureteral obstruction (UUO) has been studied in homozygous acatalasemic mutant mice (C3H/AnLCs(b)Cs(b)) compared with wild-type mice (C3H/AnLCs(a)Cs(a)). Complete UUO caused interstitial cell infiltration, tubular dilation and atrophy, and interstitial fibrosis with accumulation of type IV collagen in obstructed kidneys (OBK) of both mouse groups. However, the degree of injury showed a significant increase in OBK of acatalasemic mice compared with that of wild-type mice until day 7. The deposition of lipid peroxidation products including 4-hydroxy-2-hexenal, malondialdehyde, and 4-hydroxy-2-nonenal was severer in dilated tubules of acatalasemic OBK. Apoptosis in tubular epithelial cells significantly increased in acatalasemic OBK at day 4. Expression of caspase-9, a marker of mitochondrial pathway-derived apoptosis, increased in dilated tubules of acatalasemic mice. The level of catalase activity remained low in acatalasemic OBK until day 7 without compensatory upregulation of glutathione peroxidase activity. The data indicate that acatalasemia exacerbated oxidation of renal tissue and sensitized tubular epithelial cells to apoptosis in OBK of UUO. This study demonstrates that catalase deficiency enhanced tubulointerstitial injury and fibrosis in a murine model of UUO and thus supports the protective role of catalase in this model.