World J Gastroenterol
July 2017
Aim: To determine the number of mutations in the NS5A region of the hepatitis C virus (HCV) and its relationship to the response to antiviral therapy in patients with chronic hepatitis C genotype 1 who are non-responders to two or more treatments.
Methods: Sequences within HCV NS5A [PKR binding domain (PKRBD) and the interferon-sensitivity-determining region (ISDR)] were analysed direct sequencing in a selected cohort of 72 patients, with a total of 201 treatments [interferon-alpha (IFN-α), = 49; IFN-α + ribavirin (RBV), = 75; pegylated (peg) IFN-α + RBV, = 47; first-generation direct-acting antivirals (DAAs), = 13; and second-generation DAAs, = 17]. Of these, 48/201 achieved a sustained virological response (SVR) and 153/201 achieved no virological response (NVR).
Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that plays a critical role in diverse cellular functions, such as DNA damage detection and repair, transcriptional regulation and cell death. Furthermore, PARP-1 has emerged as a key player in the pathogenesis of multiple inflammatory diseases and has become a promising target for the treatment of cardiovascular disorders, neurodegenerative diseases and cancer. An increasing body of evidence has linked alterations in the expression levels of PARP-1, enzymatic activity and presence of polymorphism to gastrointestinal malignancies, including oesophageal, gastric, pancreas, liver and colorectal cancers.
View Article and Find Full Text PDFHepatitis C virus (HCV) is classified into seven major genotypes and 67 subtypes. Recent studies have shown that in HCV genotype 1-infected patients, response rates to regimens containing direct-acting antivirals (DAAs) are subtype dependent. Currently available genotyping methods have limited subtyping accuracy.
View Article and Find Full Text PDFDespite the introduction of protease inhibitors (PI) in the treatment of hepatitis C, the sensitivity of interferon continues to be essential to achieve a sustained virological response (SVR) and to eradicate the viral infection. Currently, pegylated interferon (PEG-IFN) and ribavirin (RBV) are required to avoid selection of PI-resistance mutations. The likelihood of obtaining an SVR with dual therapy in treatment-naïve patients with genotype 1 infection varies from 40% to 50%.
View Article and Find Full Text PDFBackground & Aims: Hepatocellular carcinoma (HCC) is associated with a poor prognosis because of a lack of effective treatment options. The objective of this study was to examine a new strategy for HCC treatment, namely the use of poly (ADP-ribose) polymerase 1 (PARP-1) inhibitor (ABT-888) together with Temozolomide (TMZ) incorporated onto magnetic nanoparticles.
Methods: Magnetic Fe3 O4 /Fe cores were encapsulated within a silica shell to facilitate the simultaneous incorporation of ABT-888 and TMZ.
This study analyses the evolution of liver disease in women with chronic hepatitis C during the third trimester of pregnancy and the post-partum period, as a natural model of immune modulation and reconstitution. Of the 122 mothers recruited to this study, 89 were HCV-RNA+ve/HIV-ve and 33 were HCV-RNA-ve/HIV-ve/HCVantibody+ve and all were tested during the third trimester of pregnancy, at delivery and post-delivery. The HCV-RNA+ve mothers were categorized as either Type-A (66%), with an increase in ALT levels in the post-partum period (>40 U/L; P<0.
View Article and Find Full Text PDFUnlabelled: The vertical transmission of hepatitis C virus (HCV-VT) is a major route of HCV infection in children, but the risk factors remain incompletely understood. This study analyzed the role of interleukin 28B (IL28B) in HCV-VT and in the spontaneous clearance of HCV among infected infants. Between 1991 and 2009, 145 mothers were recruited for this study: 100 were HCV-RNA+ve / human immunodeficiency virus negative (HIV-ve), with 128 children, and 33 were HCV-RNA-ve/HCV antibody+ve, with 43 children.
View Article and Find Full Text PDFUnlabelled: Hepatocellular carcinoma (HCC) is associated with a poor prognosis due to a lack of effective treatment options. In HCC a significant role is played by DNA damage and the inflammatory response. Poly (ADP-ribose) polymerase-1 (PARP-1) is an important protein that regulates both these mechanisms.
View Article and Find Full Text PDFAutophagy is a lysosome-dependent degradative pathway frequently activated in tumor cells treated with chemotherapy or radiation. PARP-1 has been implicated in different pathways leading to cell death and its inhibition potentiates chemotherapy-induced cell death. Whether PARP-1 participates in the cell's decision to commit to autophagy following DNA damage is still not known.
View Article and Find Full Text PDFATM and PARP-1 are two of the most important players in the cell's response to DNA damage. PARP-1 and ATM recognize and bound to both single and double strand DNA breaks in response to different triggers. Here we report that ATM and PARP-1 form a molecular complex in vivo in undamaged cells and this association increases after gamma-irradiation.
View Article and Find Full Text PDF