Undetectable HBV DNA at month 12 of entecavir treatment predicts maintained viral suppression and HBeAg-seroconversion in chronic hepatitis B patients at 3 years.

BACKGROUND: On-treatment monitoring of serum hepatitis B virus (HBV) DNA to guide treatment strategy for patients on entecavir has received little attention. AIM: To investigate the predictive value of on-treatment HBV DNA levels for responses to entecavir. METHODS: This was a retrospective cohort study among nucleos(t)ide analogue-naïve HBV-infected patients on entecavir with a minimum follow-up of 2 years. Maintained virological suppression was defined as undetectable HBV DNA (<20 IU/mL) until the last visit. Genotypic drug resistance was screened by using the INNO-LiPA DR assay. RESULTS: A total of 440 chronic hepatitis B patients (160 HBeAg-positive) followed for 34 ± 9 months were included. The cumulative probability of maintained virological suppression at year 1, 2 and 3 were 76.5%, 83.0% and 88.3% respectively. On multivariate analysis, lower baseline HBV DNA, undetectable HBV DNA at month 12 and negative HBeAg were the independent predictors of maintained virological suppression. M12 responders (who had undetectable HBV DNA at month 12) had higher probability of maintained virological suppression at 3 years (99.1%) as compared to non responders (57.5%; P < 0.001). The cumulative probability of HBeAg-seroconversion at year 1, 2 and 3 were 19.0%, 27.2% and 33.5% respectively. M12 responders had higher probability of HBeAg-seroconversion at 3 years (43.2%) than the non responders (19.0%; P = 0.003). M12 responders had lower probability of drug resistance at 3 years (0%) than the non responders (2.6%; P = 0.004). CONCLUSION: Month 12 HBV DNA responses could predict the probability of maintained virological suppression, HBeAg-seroconversion and risk of drug resistance among patients on entecavir treatment at 3 years.

Absence of cyclin D2 expression is associated with promoter hypermethylation in gastric cancer.

Expression of cyclin D2 is absent in 30-70% of gastric cancers. We investigated the role of promoter hypermethylation in the transcriptional silencing of cyclin D2 in five gastric cell lines and 47 primary gastric carcinomas. CpG island methylation status of the cyclin D2 gene was studied by methylation-specific polymerase chain reaction and bisulphite sequencing. RNA and protein expression was analysed by reverse transcription-PCR and Western blot, respectively. Dense methylation of cyclin D2 was detected in three cell lines (KATOIII, AGS and NCI-N87), which also lacked cyclin D2 mRNA and protein expression. Bisulphite DNA sequencing revealed that loss of cyclin D2 expression was closely associated with the density of methylation in the promoter region. Treatment with DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine, restored the cyclin D2 expression level in methylated gastric cells. Among the 47 primary gastric cancers, cyclin D2 hypermethylation was detected in 23 (48.9%) cases. None of the 23 normal gastric biopsies from noncancer patients showed hypermethylation. Hypermethylation was associated with loss of mRNA (P&<0.001) and protein (P=0.006) expressions. Our study showed that cyclin D2 hypermethylation is associated with loss of cyclin D2 expression in a subset of gastric cancers, which may suggest an alternative gastric carcinogenesis pathway in the absence of cyclin D2 expression.