Anti-hepatitis C virus seropositivity is not associated with metabolic syndrome irrespective of age, gender and fibrosis.

Although many studies have tried to clarify the association between hepatitis C virus (HCV) infection and metabolic syndrome, few studies have comprehensively assessed their relationship stratified by different demographic characteristics. We aimed to investigate the correlation between metabolic syndrome and anti-HCV seropositivity in Taiwan. This study enrolled consecutive subjects who had received health check-up services at Taipei Veterans General Hospital from 2002 to 2009. Metabolic syndrome was diagnosed according to the criteria defined by the International Diabetes Federation Task Force on Epidemiology and Prevention. Among the 30616 subjects enrolled in this study, the prevalence of positive anti-HCV serology was 2.7%, and 28.8% were diagnosed with metabolic syndrome. By multivariate analysis, metabolic syndrome was associated with higher body mass index, older age, male sex, a higher level of alanine aminotransferase, gamma-glutamyltransferase, platelet count and the presence of fatty liver whereas anti-HCV seropositivity was not an independent variable for metabolic syndrome. Further stratifying the subjects by age and sex, and there was still no significant difference in HCV status between those with and without metabolic syndrome. Moreover, the stage of liver fibrosis represented by aspartate aminotransferase to platelet ratio index was also not correlated with metabolic syndrome in the subjects with anti-HCV seropositivity. In conclusion, although subjects with anti-HCV seropositivity had higher fasting glucose levels and lower cholesterol and triglyceride levels compared to those with negative anti-HCV test, anti-HCV seropositivity was not associated with metabolic syndrome based on the current diagnostic criteria irrespective of age, gender and the stage of hepatic fibrosis.

RNAi-mediated silencing of the Bmi-1 gene causes growth inhibition and enhances doxorubicin-induced apoptosis in MCF-7 cells.

The oncogene Bmi-1 is a member of the Polycomb group gene family. Its expression is found to be greatly increased in a number of malignant tumors including breast cancer. This could suggest Bmi-1 as a potent therapeutic target. In this study, RNAi was introduced to down-regulate the expression of Bmi-1 in a highly malignant breast adenocarcinoma cell line, MCF-7. A thorough study of the biological behavior and chemosensitivity changes of the MCF-7 cells was carried out in context to the therapeutic potential of Bmi-1. The results obtained indicated that siRNA targeting of Bmi-1 could lead to an efficient and specific inhibition of endogenous Bmi-1 activity. The mRNA and protein expression of Bmi-1 were determined by RT-PCR and Western blot, respectively. Furthermore, silencing of Bmi-1 resulted in a drastic inhibition of the growth of MCF-7 cells as well as G(1) /S phase transition. The number of target cells was found to increase in phase G (0) /G (1) and decrease in the S phase, but no increase in the basal level of apoptosis was noticed. On the other hand, a reduction in the expression of cyclin D1 and an increase in the expression of p21 were also noticed. Silencing of Bmi-1 made the MCF-7 cells more sensitive to the chemotherapeutic agent doxorubicin and induced a significantly higher percentage of apoptotic cells. Here, we report on a study regarding the RNAi-mediated silencing of the Bmi-1 gene in breast cancer.

RNAi-mediated silencing of the Bmi-1 gene causes growth inhibition and enhances doxorubicin-induced apoptosis in MCF-7 cells

The oncogene Bmi-1 is a member of the Polycomb group gene family. Its expression is found to be greatly increased in a number of malignant tumors including breast cancer. This could suggest Bmi-1 as a potent therapeutic target. In this study, RNAi was introduced to down-regulate the expression of Bmi-1 in a highly malignant breast adenocarcinoma cell line, MCF-7. A thorough study of the biological behavior and chemosensitivity changes of the MCF-7 cells was carried out in context to the therapeutic potential of Bmi-1. The results obtained indicated that siRNA targeting of Bmi-1 could lead to an efficient and specific inhibition of endogenous Bmi-1 activity. The mRNA and protein expression of Bmi-1 were determined by RT-PCR and Western blot, respectively. Furthermore, silencing of Bmi-1 resulted in a drastic inhibition of the growth of MCF-7 cells as well as G1/S phase transition. The number of target cells was found to increase in phase G0/G1 and decrease in the S phase, but no increase in the basal level of apoptosis was noticed. On the other hand, a reduction in the expression of cyclin D1 and an increase in the expression of p21 were also noticed. Silencing of Bmi-1 made the MCF-7 cells more sensitive to the chemotherapeutic agent doxorubicin and induced a significantly higher percentage of apoptotic cells. Here, we report on a study regarding the RNAi-mediated silencing of the Bmi-1 gene in breast cancer.