A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: chronic illnesses, medication and family history

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A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: physical activity reduces colorectal cancer risk

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A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: dietary determinants of colorectal cancer risk

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Genetic-guided screening programme for familial adenomatous polyposis: result of a regional registry

Conference Theme: Challenges to specialists in the 21st centurypublished_or_final_versio

Phenotype and management of patients with familial adenomatous polyposis in Hong Kong: perspective of the Hereditary Gastrointestinal Cancer Registry.

OBJECTIVES: To report on the phenotypic spectrum and clinical management of Chinese patients suffering from the rare autosomal dominant colorectal cancer syndrome of familial adenomatous polyposis. DESIGN: Analysis of prospectively collected data from the database of a regional registry. SETTING: The Hereditary Gastrointestinal Cancer Registry, Hong Kong. PARTICIPANTS: One hundred and eight patients with proven familial adenomatous polyposis from 36 local Chinese families with the condition recruited to the Registry from 1995 to 2001. INTERVENTIONS: Screening programme for at-risk family members, prophylactic surgery at presymptomatic diagnosis, and surveillance programme for extracolonic lesions in affected individuals. MAIN OUTCOME MEASURES: Rate of colorectal cancer, type of surgical treatment, spectrum of extracolonic lesions, and management of the syndrome. RESULTS: Fifty patients suffered from colorectal cancer with a mortality rate of 78.0%. The strategy of presymptomatic diagnosis by screening and appropriate prophylactic surgery reduced the incidence of colorectal cancer. Affected individuals were prone to develop potentially serious extracolonic lesions including thyroid cancer (5.7%), desmoid tumour (15.7%), gastroduodenal adenomas (7.1%), duodenal microadenoma (17.1%), and pouch polyposis (17.4%). CONCLUSIONS: Screening and prophylactic surgery are effective ways to prevent colorectal cancer for patients with familial adenomatous polyposis. Lifelong regular surveillance is necessary to detect and manage extracolonic lesions. A dedicated registry is essential to coordinate clinical management and to compile data for furthering knowledge of this rare but complex syndrome.published_or_final_versio

Colonoscopic surveillance and screening for familial colorectal cancer: experience of a regional registry

Conference Theme: Challenges to specialists in the 21st centurypublished_or_final_versio

Granulin-epithelin precursor is an oncofetal protein defining hepatic cancer stem cells

Background and Aims: Increasing evidence has suggested that hepatocellular carcinoma (HCC) might originate from a distinct subpopulation called cancer stem cells (CSCs), which are responsible for the limited efficacy of conventional therapies. We have previously demonstrated that granulin-epithelin precursor (GEP), a pluripotent growth factor, is upregulated in HCC but not in the adjacent non-tumor, and that GEP is a potential therapeutic target for HCC. Here, we characterized its expression pattern and stem cell properties in fetal and cancerous livers. Methods: Protein expression of GEP in fetal and adult livers was examined in human and mouse models by immunohistochemical staining and flow cytometry. Liver cancer cell lines, isolated based on their GEP and/or ATP-dependent binding cassette (ABC) drug transporter ABCB5 expression, were evaluated for hepatic CSC properties in terms of colony formation, chemoresistance and tumorigenicity. Results: We demonstrated that GEP was a hepatic oncofetal protein that expressed in the fetal livers, but not in the normal adult livers. Importantly, GEP+ fetal liver cells co-expressed the embryonic stem (ES) cell-related signaling molecules including β-catenin, Oct4, Nanog, Sox2 and DLK1, and also hepatic CSC-markers CD133, EpCAM and ABCB5. Phenotypic characterization in HCC clinical specimens and cell lines revealed that GEP+ cancer cells co-expressed these stem cell markers similarly as the GEP+ fetal liver cells. Furthermore, GEP was shown to regulate the expression of ES cell-related signaling molecules β-catenin, Oct4, Nanog, and Sox2. Isolated GEP high cancer cells showed enhanced colony formation ability and chemoresistance when compared with the GEP low counterparts. Co-expression of GEP and ABCB5 better defined the CSC populations with enhanced tumorigenic ability in immunocompromised mice. Conclusions: Our findings demonstrate that GEP is a hepatic oncofetal protein regulating ES cell-related signaling molecules. Co-expression of GEP and ABCB5 further enriches a subpopulation with enhanced CSC properties. The current data provide new insight into the therapeutic strategy. © 2011 Cheung et al.published_or_final_versio

Clinical significance of serum vascular cell adhesion molecule-1 levels in patients with hepatocellular carcinoma

Aim: To evaluate the correlation between serum vascular cellular adhesion molecule-1 (VCAM-1) levels and clinicopathological features in patients with hepatocellular carcinoma (HCC). Methods: Ninety-six patients who underwent HCC resection were recruited in the study. Preoperative serum levels of soluble VCAM-1 were measured by enzyme-linked immunosorbent assay. Results: Serum VCAM-1 level in HCC patients was inversely correlated with platelet count (r=-0.431, P<0.001) and serum albumin level (r=-0.279, P<0.001), and positively correlated with serum bilirubin level (r=-0.379, P<0.001). Serum VCAM-1 level was not associated with tumor characteristics such as tumor size, venous invasion, presence of microsatellite nodules, tumor grade and tumor stage. Serum VCAM-1 level was significantly higher in HCC patients with cirrhosis compared with those without cirrhosis (median 704 vs 546 ng/mL, P<0.001). Furthermore, a significantly better disease-free survival was observed in HCC patients with low VCAM-1 level (P=0.019). Conclusion: Serum VCAM-1 level appears to reflect the severity of underlying chronic liver disease rather than the tumor status in HCC patients, and low preoperative serum VCAM-1 level is predictive of better disease-free survival after surgery. Copyright © 2004 by The WJG Press.published_or_final_versio

Microsatellite instability and mismatch repair gene mutations are common in young colorectal cancer patients in Hong Kong

Conference Theme: Challenges to Specialists in the 21st centurypublished_or_final_versio

The prevalence of Helicobacter pylori carrier rates among the healthy blood donors in Hong Kong

A serological assay was employed in this study to assess the Helicobacter pylori carrier rates among the healthy blood donors (all Chinese) in Hong Kong. The commercial kit for detecting anti-H. pylori antibody titres was found to have a sensitivity of 84% and a specificity of 85% by using the histochemistry results as the gold standard. Elevated anti-H. pylori antibody titres were observed in 42.4%, 53.2% and 72.2% of the healthy blood donors of age below 20, 21 to 30 and 31 to 40 years respectively. This indicates a steady rise of H. pylori carrier rates with age. The overall H. pylori prevalence rate was 54.9%. The positivity of H. pylori in teenagers appeared to be double that reported in Western countries. Whether this is related to the younger age of peptic ulcer presentation in Hong Kong compared with Western countries is not known. However, there was no significant difference of the H. pylori rates between males and females of each age group although a male predominance has been well established for peptic ulcer in Hong Kong.published_or_final_versio