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Farnesyl transferase inhibitors (FTIs) are novel antitumor drugs with clinical activity. FTIs inhibit cell growth not only by preventing direct Ras farnesylation but also through a Ras-independent pathway. Proteomics has been shown to be a powerful tool to monitor and analyze molecular networks and fluxes within the living cells and to identify the proteins that participate in these networks upon perturbation of the cellular environment. To observe early and dynamic protein changes in the cellular response to FTI in ovarian cancer cells, total proteins were extracted from 2774 cells treated or not with 10 microM manumycin, an FTI, for 3, 6 and 16 h. The proteins in the cells that were differentially expressed following treatment with manumycin for 3, 6 and 16 h were noted by two-dimensional electrophoresis and further identified by peptide mass fingerprinting as stress proteins. Both heat shock protein 70 (HSP70) and altered HSP70 were significantly up-regulated as early as 16 h in 2774 cells after exposure to manumycin. Since HSP70 plays an important role in protecting cells under stress, we treated the 2774 cells with the HSP inhibitor quercetin in combination with FTI. Quercetin dramatically enhanced the manumycin-mediated apoptosis in 2774 cells. Inducible HSP70 by manumycin in surviving ovarian cancer cells was also inhibited by quercetin as demonstrated by enzyme-linked immunosorbent assay. The inhibition of HSP70 by quercetin was correlated with enhancement of manumycin-induced mediated apoptosis in 2774 cells. The inhibition of HSP70 by 50 microM quercetin was also correlated with a decreased expression of procaspase-3 and enhancement of specific cleavage of poly (ADP-ribose) polymerase into apoptotic fragment in 2774 cells treated with manumycin. The interaction between the HSP70 inhibitor and FTI confirms the functional significance of the up-regulation of HSP70 as a protective mechanism against FTI-induced apoptosis and provides the framework for combination treatment of ovarian cancer.

Abstract. Alterations of the epidermal growth factor receptor (EGFR), including overexpression or gene mutations, contribute to the malignant transformation of human epithelial cells. The aim of this study was to assess EGFR overexpression or gene amplification in esophageal squamous cell carcinoma (ESCC) tissue samples and investigate their correlations with biological behaviors. Tissue specimens from 56 patients with surgically resected ESCC were obtained for immunohistochemical analysis of EGFR expression and fluorescence in situ hybridization analysis of EGFR amplification. The data were statistically analyzed to determine the associations with patient clinicopathological and survival data. EGFR was overexpressed in 30 of the 56 (53.6%) ESCC samples and was associated with poor tumor differentiation (P=0.047). EGFR amplification was detected in 13 cases (23.2%) and was associated with advanced pathological stage (P=0.042) and tumor lymph node metastasis (P=0.002). The univariate analysis identified no association between EGFR overexpression and the overall survival (OS) of the patients. By contrast, EGFR amplification predicted ESCC prognosis (P= 0.031), while the multivariate analysis revealed a marginal statistical significance for the association between EGFR amplification and OS (P=0.056). EGFR overexpression and increased EGFR copy number were common events in ESCC and contributed to malignant biological behaviors, including tumor dedifferentiation and lymph node metastasis. EGFR amplification may therefore be useful in predicting OS in patients with ESCC. IntroductionEsophageal cancer represents the sixth most frequent cause of cancer-related mortality worldwide (1). Histologically, esophageal cancer is classified primarily as either squamous cell carcinoma (SCC) or adenocarcinoma. Esophageal SCC (ESCC) accounts for approximately one-third of esophageal cancer cases in the United States and >90% of esophageal cancer cases worldwide (2,3). The risk factors for ESCC include tobacco smoking, heavy alcohol consumption and a diet lacking fresh fruits and vegetables (2,3). To date, the prognosis of esophageal SCC remains poor, despite improvements in surgical techniques, perioperative management, chemotherapy and/or radiotherapy (4-6). Thus, studies on early detection, novel treatment options, prevention and predictive tumor markers for ESCC treatment and prognosis are urgently required.Epidermal growth factor receptor (EGFR) is a part of an important transmembrane signal transduction pathway in human epithelial cells and altered EGFR protein expression or gene amplification occurs in a number of solid tumors, including esophageal cancer (7-13). EGFR-mediated signaling is crucial for cell proliferation, as well as for cancer progression, including tumor angiogenesis, metastasis and cancer cell resistance to apoptosis. EGFR overexpression is mostly due to EGFR gene amplification or mutations, with the latter occurring frequently in EGFR exons 18-21, which encode the tyrosine kinase section of the EGFR protein...

BackgroundHepatitis B virus (HBV) infection has remained a significant public health problem. Generating a large-scale, community-based profile of HBV infection in China is essential to prevention of the disease.ObjectivesThe current study was designed to investigate HBV-infected individuals at the community level and determine the age distribution, hepatitis B e antigen (HBeAg) positivity and its related risk factors, relationship among serological markers.Patients and MethodsA cross-sectional, community-based survey was carried out without age restriction, in 12 communities of two counties. The study population was selected by random multistage cluster sampling. Serological samples and demographic information were collected from 8439 HB surface antigen (HBsAg)-positive individuals.ResultsThe constituent ratio of individuals with HBsAg-positive infections was lowest among persons aged < 20 years (0.4%) and the highest among persons aged 40-49 years (33.2%). The HBeAg-positive rate among infected individuals was 18.5%, and the constituent ratio decreased with increasing of age. The HBeAg-positive rate in males (21.9%) was significantly higher than in females (14.7%), and was higher among coastland inhabitants (22.9%) than among plains inhabitants (12.9%). Among the 1561 HBeAg-positive individuals, 91.0% were HBV DNA-positive. However, of the 6878 HBeAg-negative individuals, only 45.4% were HBV DNA-positive, and the HBeAg-positive rate was significantly different at different levels of HBV DNA expression. The proportion of detectable HBV DNA levels was significantly higher in individuals with elevated ALT, compared to those with normal ALT, regardless of HBeAg-positivity.ConclusionsThe HBV prevalence remained high in the > 20 age group. The positivity of HBeAg was related to age, region, and sex. Testing HBeAg and serum ALT levels were effective ways to assess HBV infectiousness in community-level hospitals in China.