Vincent Chi Ho Cheung

UNLABELLED: Liver tumor-initiating cells (T-ICs) are capable of self-renewal and tumor initiation and are more chemoresistant to chemotherapeutic drugs. The current therapeutic strategies for targeting stem cell self-renewal pathways therefore represent rational approaches for cancer prevention and treatment. In the present study, we found that Lup-20(29)-en-3β-ol (lupeol), a triterpene found in fruits and vegetables, inhibited the self-renewal ability of liver T-ICs present in both hepatocellular carcinoma (HCC) cell lines and clinical HCC samples, as reflected by hepatosphere formation. Furthermore, lupeol inhibited in vivo tumorigenicity in nude mice and down-regulated CD133 expression, which was previously shown to be a T-IC marker for HCC. In addition, lupeol sensitized HCC cells to chemotherapeutic agents through the phosphatase and tensin homolog (PTEN)-Akt-ABCG2 pathway. PTEN plays a crucial role in the self-renewal and chemoresistance of liver T-ICs; down-regulation of PTEN by a lentiviral-based approach reversed the effect of lupeol on liver T-ICs. Using an in vivo chemoresistant HCC tumor model, lupeol dramatically decreased the tumor volumes of MHCC-LM3 HCC cell line-derived xenografts, and the effect was equivalent to that of combined cisplatin and doxorubicin treatment. Lupeol exerted a synergistic effect without any adverse effects on body weight when combined with chemotherapeutic drugs. CONCLUSION: Our results suggest that lupeol may be an effective dietary phytochemical that targets liver T-ICs.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is often associated with metastasis and recurrence leading to a poor prognosis. Therefore, development of novel treatment regimens is urgently needed to improve the survival of HCC patients. In this study, we aimed to investigate the in vitro and in vivo effects of anti-CD47 antibody alone and in combination with chemotherapy in HCC. METHODS: In this study, we examined the functional effects of anti-CD47 antibody (B6H12) on cell proliferation, sphere formation, migration and invasion, chemosensitivity, macrophage-mediated phagocytosis and tumourigenicity both in vitro and in vivo. The therapeutic efficacy of anti-CD47 antibody alone or in combination with doxorubicin was examined in patient-derived HCC xenograft. RESULTS: Blocking CD47 with anti-CD47 monoclonal antibody (B6H12) at 10 μg/ml could suppress self-renewal, tumourigenicity and migration and invasion abilities of MHCC-97L and Huh-7 cells. Interestingly, anti-CD47 antibody synergized the effect of HCC cells to chemotherapeutic drugs including doxorubicin and cisplatin. Blockade of CD47 by anti-CD47 antibody induced macrophage-mediated phagocytosis. Using a patient-derived HCC xenograft mouse model, we found that anti-CD47 antibody (400 μg/mouse) in combination with doxorubicin (2 mg/kg) exerted maximal effects on tumour suppression, as compared with doxorubicin and anti-CD47 antibody alone. CONCLUSIONS: Anti-CD47 antibody treatment could complement chemotherapy which may be a promising therapeutic strategy for the treatment of HCC patients.

BACKGROUND AND AIM: Gastrointestinal (GI) diseases account for substantial morbidity, mortality, and health care utilization. This public hospital-based study assessed the incidence and time trend of hospitalization and mortality of major GI diseases over one decade. METHODS: We conducted an observational study using population-wide database managed by the Hong Kong Hospital Authority with a principal diagnosis of GI diseases defined by International Classification of Disease, 9th Revision, Clinical Modification coding. We measured age-standardized incidence of hospitalization, emergency admissions, multiple admissions, and in-hospital mortality from 2005 to 2014 using Poisson regression. RESULTS: The annual incidence of hospitalization for GI diseases increased from 4713 to 5241 per 100 000 discharges (incidence rate ratio [IRR] = 1.004; 95% confidence interval [CI]: 1.003-1.005). GI infections and cancers showed the highest rates of hospitalization in 2014. Hospitalization for GI cancers (IRR = 1.014; 95% CI: 1.013-1.016) and non-infectious enterocolitis (IRR = 1.058; 95% CI: 1.055-1.061) increased, whereas peptic ulcer disease has decreased. Hospitalization for Crohn's disease showed the most significant rise (126%). Annual incidence of hospitalization for Clostridium difficile infections increased by fivefold (IRR = 1.221; 95% CI: 1.178-1.266), while a 66% reduction was observed for peptic ulcer bleeding (IRR = 0.894; 95% CI: 0.889-0.899). GI cancers had the highest in-hospital mortality rate in 2014, especially colorectal cancer and gastric cancer. CONCLUSIONS: This study showed an increased hospitalization burden of GI cancers and Crohn's disease, and a reduction in overall mortality for GI diseases. These data provide insight into epidemiological changes of GI diseases in the 21st century and implications for hospital burden and need of resource re-allocation.