Current progress in the treatment of chronic hepatitis C

Over the last decade, the standard of care for the treat- ment of chronic hepatitis C has been the combination of pegylated-interferon-alfa （PEG-IFN） and ribavirin （RBV） which results in sustained virological response （SVR） rates of 75%-85% in patients with genotypes 2 or 3 but only of 40%-50% in patients with genotype 1. Cur- rently, there are rapid and continuous developments of numerous new agents against hepatitis C virus （HCV）, which are the focus of this review. Boceprevir and tela- previr, two first-generation NS3/4A HCV protease inhibi- tors, have been recently licensed in several countries around the world to be used in combination with PEG- IFN and RBV for the treatment of genotype 1 patients. Boceprevir or telaprevir based triple regimens, com- pared with the PEG-IFN/RBV combination, improve the SVR rates by 25%-31% in treatment-naTve genotype 1 patients, by 40%-64% in prior relapsers, by 33%-45% in prior partial responders and by 24%-28% in prior null responders. At the same time, the application of response-guided treatment algorithms according to the on-treatment virological response results in shortening of the total therapy duration to only 24 wk in 45%-55% of treatment-na＇ive patients. There are, however, several challenges with the use of the new triple combinations in genotype 1 patients, such as the need for immediate results of HCV RNA testing using sensitive quantitative assays, new and more frequent adverse events （anemia and dysgeusia for boceprevir; pruritus, rash and anemia for telaprevir）, new drug interactions and increasing dif- ficulties in compliance. Moreover, the SVR rates are still poor in very difficult to treat subgroups of genotype 1 patients, such as null responders with cirrhosis, while there is no benefit for patients who cannot tolerate PEG- IFN/RBV or who are infected with non-1 HCV genotype. Many newer anti-HCV agents of different classes and numerous combinations are currently under evaluation with encouraging results. Preliminary data suggest that the treatment of chronic HCV patients with well toler- ated combinations of oral agents without PEG-IFN is feasible and may lead to a universal HCV cure over the next 5-10 years.

Interplay between hepatitis B virus and the innate immune responses:implications for new therapeutic strategies

Hepatitis B virus(HBV) infection is still a worldwide health problem;however,the current antiviral therapies for chronic hepatitis B are limited in efficacy.The outcome of HBV infection is thought to be the result of complex interactions between the HBV and the host immune system.While the role of the adaptive immune responses in the resolution of HBV infection has been well characterized,the contribution of innate immune mechanisms remains elusive until recent evidence implicates that HBV appears to activate the innate immune response and this response is important for controlling HBV infection.Here,we review our current understanding of innate immune responses to HBV infection and the multifaceted evasion by the virus and discuss the potential strategies to combat chronic HBV infection via induction and restoration of host innate antiviral responses.

Beneficial effects of fucoidan in patients with chronic hepatitis C virus infection

AIM:To evaluate the effects of fucoidan,a complex sulfated polysaccharide extract from marine seaweed,on hepatitis C virus(HCV) RNA load both in vitro and in vivo.METHODS:HCV-1b replicon-expressing cells were cultured in the presence of fucoidan obtained from Cladosiphon okamuranus Tokida cultivated in Okinawa,Japan,and quantified the level of HCV replication.In an open-label uncontrolled study,15 patients with chronic hepatitis C,and HCV-related cirrhosis and hepatocellular carcinoma were treated with fucoidan(0.83 g/d) for 12 mo.The clinical symptoms,biochemical tests,and HCV RNA levels were assessed before,during,and after treatment.RESULTS:Fucoidan dose-dependently inhibited the expression of HCV replicon.At 8-10 mo of treatment with fucoidan,HCV RNA levels were significantly lower relative to the baseline.The same treatment also tended to lower serum alanine aminotransferase levels,and the latter correlated with HCV RNA levels.However,the improved laboratory tests did not translate into significant clinical improvement.Fucoidan had no serious adverse effects.CONCLUSION:Our findings suggest that fucoidan is safe and useful in the treatment of patients with HCVrelated chronic liver diseases.Further controlled clinical trials are needed to confirm the present findings.

Inhibition of lung cancer stem cells self-renewal and tumorigenicity by lentivirus-delivered Bmi1 shRNA

Objective： The aim of the study was to observe the effect of Bmil reduction on the self-renewal and tumorigenicity ability of lung cancer stem cells （LCSCs） in human lung adenocarcinoma. Methods： Human lung adenocarcinoma cells A549 were consecutively passaged in NOD/SCID mice treated with Paclitaxel weekly. The proportions of LCSCs in A549 cells and the cells from the third passage （A549-3rd） were compared. The expression of Bmil in LCSCs was silenced by intratumoral injection with lentivirus-delivered Broil small hairpin RNA （shRNA）. RT-PCR and Western blot were used to test the mRNA and protein expressions of Broil in LCSCs. The protein level of p16INK4A was analyzed by Western blotting. The self- renewal and tumorigenicity ability of LCSCs were evaluated by counting the sphere formation rate in serum-free medium and the tumor formation rate in NOD/SCID mice. Results： In vivo passaging ofA549 cells under chemotherapy pressure enriched for LCSCs. The expression of Broil in LCSCs increased. Down-regulation of Bmil by RNA interference resulted in reduced self-renewal and tumorigenicity ability of LCSCs and paralleled the increased expression of p16INK4A, a Bmil target. Conclu- sion： Broil regulates self-renewal and tumorigenicity of LCSCs by silencing some target genes, including p16INK4A.