3.RNA interference as a novel treatment strategy for chronic hepatitis B infection
Rex Wan-Hin HUI ; Lung-Yi MAK ; Wai-Kay SETO ; Man-Fung YUEN
Clinical and Molecular Hepatology 2022;28(3):408-424
Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality. Functional cure of CHB, defined as sustainable hepatitis B surface antigen (HBsAg) seroclearance, is associated with improved clinical outcomes. However, functional cure is rarely attainable by current treatment modalities. RNA interference (RNAi) by small-interfering RNA (siRNA) and anti-sense oligonucleotide (ASO) has been studied as a novel treatment strategy for CHB. RNAi targets post-transcriptional messenger RNAs and pregenomic RNAs to reduce hepatitis B virus (HBV) antigen production and viral replication. By reducing viral antigens, host immune reconstitution against HBV may also be attained. Phase I/II trials on siRNAs have demonstrated them to be safe and well-tolerated. siRNA is effective when given in monthly doses with different total number of doses according to different trial design, and can lead to sustainable dose-dependent mean HBsAg reduction by 2–2.5 log. Incidences of HBsAg seroclearance after siRNA therapy have also been reported. ASOs have also been studied in early phase trials, and a phase Ib study using frequent dosing regimen within 4 weeks could achieve similar HBsAg reduction of 2 log from baseline. Given the established efficacy and safety of nucleos(t) ide analogues (NAs), future RNAi regimens will likely include NA backbone. While the current evidence on RNAi appears promising, it remains undetermined whether the potent HBsAg reduction by RNAi can result in a high rate of HBsAg seroclearance with durability. Data on RNAi from phase IIb/III trials are keenly anticipated.
5.Epidemiology of Hepatocellular Carcinoma in the Asia-Pacific Region.
Ran Xu ZHU ; Wai Kay SETO ; Ching Lung LAI ; Man Fung YUEN
Gut and Liver 2016;10(3):332-339
Hepatocellular carcinoma (HCC) is the predominant primary liver cancer in many countries and is the third most common cause of cancer-related death in the Asia-Pacific region. The incidence of HCC is higher in men and in those over 40 years old. In the Asia-Pacific region, chronic hepatitis B virus and hepatitis C virus infections are the main etiological agents; in particular, chronic hepatitis B infection (CHB) is still the major cause in all Asia-Pacific countries except for Japan. Over the past two decades, the incidence of HCC has remained stable in countries in the region except for Singapore and Hong Kong, where the incidence for both sexes is currently decreasing. Chronic hepatitis C infection (CHC) is an important cause of HCC in Japan, representing 70% of HCCs. Over the past several decades, the prevalence of CHC has been increasing in many Asia-Pacific countries, including Australia, New Zealand, and India. Despite advancements in treatment, HCC is still an important health problem because of the associated substantial mortality. An effective surveillance program could offer early diagnosis and hence better treatment options. Antiviral treatment for both CHB and CHC is effective in reducing the incidence of HCC.
Australia
;
Carcinoma, Hepatocellular*
;
Early Diagnosis
;
Epidemiology*
;
Hepacivirus
;
Hepatitis B, Chronic
;
Hepatitis C, Chronic
;
Hong Kong
;
Humans
;
Incidence
;
India
;
Japan
;
Liver Neoplasms
;
Male
;
Mortality
;
New Zealand
;
Prevalence
;
Singapore
6.New Biomarkers of Chronic Hepatitis B
Lung Yi MAK ; Wai Kay SETO ; James FUNG ; Man Fung YUEN
Gut and Liver 2019;13(6):589-595
Chronic hepatitis B (CHB) infection leads to clinically heterogeneous disease outcomes. Different viral markers are utilized to monitor treatment effects and predict risk of complications in patients with CHB. Hepatitis B core-related antigen (HBcrAg) is a novel serum composite viral protein whose performance has been proven to be superior to that of existing viral markers. It showed good correlation with intrahepatic covalently closed-circular DNA. Its profile differs drastically in patients in different disease phases, and the level declines with antiviral therapies. HBcrAg may be helpful for predicting hepatocellular carcinoma development and hepatitis B virus (HBV) reactivation in immunosuppressed patients. Another emerging measurable serum marker, HBV RNA, exists in the form of pregenomic RNA-containing virions. Its profile differs between patients in different disease phases in a similar manner to that of HBcrAg. HBV RNA is present in serum at lower levels than HBV DNA in treatment-naive patients by 1–2 logs. In contrast, its level is higher than HBV DNA in patients receiving nucleos(t)ide analogues (NAs). A significant decline in serum RNA was observed in patients receiving novel antiviral therapies, including core protein allosteric modulators and RIG-1/NOD2 agonists. Both HBcrAg and HBV RNA may be helpful for predicting off-therapy sustained virological control in patients who stop long-term NA treatment.
Biomarkers
;
Carcinoma, Hepatocellular
;
DNA
;
Hepatitis B
;
Hepatitis B virus
;
Hepatitis B, Chronic
;
Hepatitis, Chronic
;
Humans
;
RNA
;
Virion
7.The role of different viral biomarkers on the management of chronic hepatitis B
Lung-Yi MAK ; Rex Wan-Hin HUI ; James FUNG ; Wai Kay SETO ; Man-Fung YUEN
Clinical and Molecular Hepatology 2023;29(2):263-276
Chronic hepatitis B infection is a major public health challenge. With the advancement in technology, various components of the viral cycle can now be measured in the blood to assess viral activity. In this review article, we summarize the relevant data of how antiviral therapies impact viral biomarkers, and discuss their potential implications. Viral nucleic acids including hepatitis B virus (HBV) double-stranded deoxy-ribonucleic acid (DNA) and to a lesser extent, pre-genomic RNA, are readily suppressed by nucleos(t)ide analogues (NUCs). The primary role of these markers include risk prediction for hepatocellular carcinoma (HCC) and risk stratification for partial cure, defined as off-therapy virological control, or functional cure, defined as hepatitis B surface antigen (HBsAg) seroclearance plus undetectable serum HBV DNA for ≥6 months. Viral translational products including hepatitis e antigen, quantitative HBsAg and hepatitis B core-related antigen can be reduced by NUCs and pegylated interferon a. They are important in defining disease phase, delineating treatment endpoints, and predicting clinical outcomes including HCC risk and partial/ functional cure. As the primary outcome of phase III trials in chronic hepatitis B is set as HBsAg seroclearance, appropriate viral biomarkers can potentially inform the efficacy of novel compounds. Early viral biomarker response can help with prioritization of subjects into clinical trials. However, standardization and validation studies would be crucial before viral biomarkers can be broadly implemented in clinical use.
8.Screening strategy for non-alcoholic fatty liver disease
Saisai ZHANG ; Lung-Yi MAK ; Man-Fung YUEN ; Wai-Kay SETO
Clinical and Molecular Hepatology 2023;29(Suppl):S103-S122
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, affecting approximately 25% of the general population worldwide, and is forecasted to increase global health burden in the 21st century. With the advancement of non-invasive tests for assessing and monitoring of steatosis and fibrosis, NAFLD screening is now feasible, and is increasingly highlighted in international guidelines related to hepatology, endocrinology, and pediatrics. Identifying high-risk populations (e.g., diabetes mellitus, obesity, metabolic syndrome) based on risk factors and metabolic characteristics for non-invasive screening is crucial and may aid in designing screening strategies to be more precise and effective. Many screening modalities are currently available, from serum-based methods to ultrasonography, transient elastography, and magnetic resonance imaging, although the diagnostic performance, cost, and accessibility of different methods may impact the actual implementation. A two-step assessment with serum-based fibrosis-4 index followed by imaging test vibration-controlled transient elastography can be an option to stratify the risk of liverrelated complications in NAFLD. There is a need for fibrosis surveillance, as well as investigating the cost-effectiveness of different screening algorithms and engaging primary care for first-stage triage screening.
10.Rates of metachronous adenoma after curative resection for left-sided or right-sided colon cancer.
Yuk Fai LAM ; Wai Kay SETO ; Teresa TONG ; Ka Shing CHEUNG ; Oswens LO ; Ivan FN HUNG ; Wai Lun LAW ; Wai K LEUNG
Intestinal Research 2018;16(4):619-627
BACKGROUND/AIMS: We determined the rates of metachronous colorectal neoplasm in colorectal cancer (CRC) patients after resection for right (R)-sided or left (L)-sided cancer. METHODS: Consecutive CRC patients who had undergone surgical resection for curative intent in our hospital between 2001 and 2004 were identified. R-sided colonic cancers refer to cancer proximal to splenic flexure whereas L-sided cancers include rectal cancers. Patients were included only if they had a clearing colonoscopy performed either before or within 6 months after the operation. Findings of surveillance colonoscopy performed up to 5 years after colonic resection were included in the analysis. RESULTS: Eight hundred and sixty-three CRC patients underwent curative surgical resection during the study period. Three hundred and twenty-seven patients (107 R-sided and 220 L-sided) fulfilled the inclusion criteria and had at least 1 postoperative surveillance colonoscopy performed. The proportion of patients who had polyp and adenoma on surveillance colonoscopy was significantly higher among patients with L-sided than R-sided cancers (polyps: 30.9% vs. 19.6%, P=0.03; adenomas: 25.5% vs. 13.1%, P=0.01). The mean number of adenoma per patient on surveillance colonoscopy was also higher for patients with L-sided than R-sided tumors (0.52; 95% confidence interval [CI], 0.37–0.68 vs. 0.22; 95% CI, 0.08–0.35; P < 0.01). Multivariate analysis showed that L-sided cancers, age, male gender and longer follow-up were independent predictors of adenoma detection on surveillance colonoscopy. CONCLUSIONS: Patients with Lsided cancer had a higher rate of metachronous polyps and adenoma than those with R-sided cancer on surveillance colonoscopy.
Adenoma*
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Colon*
;
Colon, Transverse
;
Colonic Neoplasms*
;
Colonoscopy
;
Colorectal Neoplasms
;
Follow-Up Studies
;
Humans
;
Male
;
Multivariate Analysis
;
Polyps
;
Rectal Neoplasms
;
Recurrence