The role of autophagy in disease pathogenesis following viral infection is beginning to be elucidated. We have previously reported that hepatitis C virus (HCV) infection in hepatocytes induces autophagy. However, the biological significance of HCV-induced autophagy has not been clarified. Autophagy has recently been identified as a novel component of the innate immune system against viral infection. In this study, we found that knockdown of autophagy-related protein beclin 1 (BCN1) or autophagy-related protein 7 (ATG7) in immortalized human hepatocytes (IHHs) inhibited HCV growth. BCN1-or ATG7-knockdown IHHs, when they were infected with HCV, exhibited increased expression of interferon-b, 2 0 ,5 0 -oligoadenylate synthetase 1, interferon-a, and interferon-a-inducible protein 27 messenger RNAs of the interferon signaling pathways in comparison with infected control IHHs. A subsequent study demonstrated that HCV infection in autophagy-impaired IHHs displayed caspase activation, poly(adenosine diphosphate ribose) polymerase cleavage, and apoptotic cell death. Conclusion: The disruption of autophagy machinery in HCV-infected hepatocytes activates the interferon signaling pathway and induces apoptosis. Together, these results suggest that HCV-induced autophagy impairs the innate immune response. (HEPATOLOGY 2011;53:406-414)

Breast cancer is one of the most common cancers among women in the United States. Although there are effective drugs for treating advanced stages of breast cancers, women eventually develop resistance. One of the approaches to control breast cancer is prevention through diet, which inhibits one or more neoplastic events and reduces cancer risk. In this study, we have used human breast cancer cells, MCF-7 and MDA-MB-231, and primary human mammary epithelial cells as an in vitro model to assess the efficacy of bitter melon (Momordica charantia) extract (BME) as an anticancer agent. BME treatment of breast cancer cells resulted in a significant decrease in cell proliferation and induced apoptotic cell death. Apoptosis of breast cancer cells was accompanied by increased poly(ADP-ribose) polymerase cleavage and caspase activation. Subsequent studies showed that BME treatment of breast cancer cells inhibited survivin and claspin expression. Fluorescence-activated cell sorting analysis suggested that MCF-7 cells treated with BME accumulated during the G 2 -M phase of the cell cycle. Further studies revealed that BME treatment enhanced p53, p21, and pChk1/2 and inhibited cyclin B1 and cyclin D1 expression, suggesting an additional mechanism involving cell cycle regulation. Together, these results show that BME modulates signal transduction pathways for inhibition of breast cancer cell growth and can be used as a dietary supplement for prevention of breast cancer. Cancer Res; 70(5); 1925-31. ©2010 AACR.

The incidence of Vibrio cholerae non-O1, non-O139 strains from hospitalized patients with acute diarrhea constituted 27.4% (n ‫؍‬ 54) of the total 197 V. cholerae strains isolated from patients in Kolkata, India, in 2003. Of 197 strains, 135 were identified as O1 serotype Ogawa and 2 were identified as O139. In the same time period, six O1 background rough strains that possessed all known virulence factors were identified. Serotype analysis of the non-O1, non-O139 strains placed 42 strains into 19 serogroups, while 12 remained O nontypeable (ONT); the existing serotyping scheme involved antisera to 206 serogroups. Detection of a good number of ONT strains suggested that additional serogroups have arisen that need to be added to the current serotyping scheme. The non-O1, non-O139 strains were nontoxigenic except for an O36 strain (SC124), which regulated expression of cholera toxin as O1 classical strains did. Additionally, strain SC124 carried alleles of tcpA and toxT that were different from those of the O1 counterpart, and these were also found in five clonally related strains belonging to different serogroups. Strains carrying tcpA exhibited higher colonization in an animal model compared to those lacking tcpA. PCR-based analyses revealed remarkable variations in the distribution of other virulence factors, including hlyA, rtxA, Vibrio seventh pandemic island I (VSP-I), VSP-II, and type III secretion system (TTSS). Most strains contained hlyA (87%) and rtxA (81.5%) and secreted cytotoxic factors when grown in vitro. Approximately one-third of the strains (31.5%) contained the TTSS gene cluster, and most of these strains were more motile and hemolytic against rabbit erythrocytes. Partial nucleotide sequence analysis of the TTSS-containing strains revealed silent nucleotide mutations within vcsN2 (type III secretion cytoplasmic ATPase), indicating functional conservation of the TTSS apparatus.In the recorded history of cholera, humans have experienced seven pandemics; the seventh pandemic is still ongoing since its commencement in 1961 (29). Cholera is a waterborne disease that afflicts millions of people every year. The etiological agent of the disease is Vibrio cholerae belonging to serogroups O1 and O139 (4, 29). Members of the O1 serogroup have been further subdivided into Ogawa and Inaba serotypes and El Tor and classical biotypes. The seventh pandemic strains are of the O1 El Tor biotype, which replaced the O1 classical biotype strains that caused previous pandemics (29). The current serotyping scheme of V. cholerae includes 206 serogroups (57). Strains belonging to serogroups other than O1 and O139 are collectively known as non-O1, non-O139 V. cholerae strains and exist in abundance in the aquatic environment. However, recent studies have concluded that considerable incidence of human diarrheal episodes in many countries, including India, is due to V. cholerae non-O1, non-O139 (10,11,27,39,40,48). Studies of diarrheal cases in Thailand between 1993 and 1995 revealed that the prevalence of non-O1, non-O13...

Hepatitis C virus (HCV) is a hepatotropic Flavivirus in theHepacivirus genus. The virus genome contains a linear, positive-strand RNA molecule of ϳ9,500 nucleotides. The HCV genome encodes a polyprotein precursor of about 3,000 amino acids, which is cleaved by both viral and host proteases into structural (core, E1, E2, and p7) and nonstructural (NS2, NS3, NS4A, NS4B, NS5A, and NS5B) proteins. A number of HCV genomes have been cloned, and sequence divergences indicate several genotypes and a series of subtypes for the virus (19). An estimated 200 million people worldwide and 4 million people in the United States are infected with HCV. The majority of the chronically HCV-infected patients develop end-stage liver disease. Currently, the treatment is limited to a combination therapy of ribavirin and alpha interferon (IFN-␣). This combination therapy is expensive and effective in ϳ50% of HCV genotype 1-infected individuals (45), and the reason for this limited efficacy is not clear. Both viral and host factors may play roles that ultimately affect the level and extent of IFNstimulated gene (ISG) expression and function induced during the course of IFN therapy (11,12,27,28). Thus, there is an urgent need to identify novel antivirals or cellular molecules that can be used for therapy. Viral proteins and nucleic acids are detected by pathogen recognition receptors (PRRs) as pathogen-associated molecular patterns (PAMPs). Subsequently, the signal transduction pathways are activated and trigger type I IFN and the production of other cytokines. Type I IFN then augments the expression of several ISGs and subverts virus replication by a variety of mechanisms (29,32). IFN orchestrates a large number of genes of this antiviral response (14). However, many viruses deploy anti-IFN countermeasures, which for HCV are enacted primarily by the viral protein NS3/4A (5). To identify host factors that modify viral replication, we performed pathwayspecific microarray of IFN-related genes. Our results identified 56 genes that were modulated between HCV-infected immortalized human hepatocytes (IHH) and IFN-pretreated, HCVinfected IHH. After validation, we focused on two IFN effector molecules, ISG56 (also known as IFIT1) and IFITM1, in determining antiviral effect in the current study. The overexpression of ISG56 is known to suppress HCV internal ribosome entry site (IRES)-mediated transcription, suggesting its potential as an anti-HCV molecule (43). On the other hand, IFITM family proteins are emerging as antiviral ISGs (2, 13, 24). Our results revealed that the exogenous expression of ISG56 or IFITM1 inhibits HCV replication and growth in infected hepatocytes. MATERIALS AND METHODSCell lines and IFN-␣. The generation of immortalized human hepatocytes (IHH) by the transfection of the HCV core was described previously (30). Huh7, Huh7.5, and IHH were maintained in Dulbecco's modified Eagle's medium (DMEM) (Cambrex, Walkersville, MD) containing 10% fetal bovine serum (FBS), 100 U/ml of penicillin G, and 100 g/ml of streptomycin at 37°C in...

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