Publications by authors named "Gulam Waris"

Chronic hepatitis C virus (HCV) infection induces liver inflammation that can lead to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Inflammation is the outcome of the action of proinflammatory cytokines and chemokines, including interleukin-1 beta (IL-1β) and tumor necrosis factor alpha. Mature IL-1β production and secretion are facilitated by active inflammasome complexes, including the NACHT-LRR pyrin domain-containing protein 3 (NLRP3) inflammasome.

View Article and Find Full Text PDF

Molecular gold(I) and platinum(II) species were examined for the inhibition of liver fibrosis and the hepatitis C virus (HCV). Determination of inhibition efficiency was conducted via morphological analysis, cell viability, western blot analysis, and quantitative reverse transcription polymerase chain reaction (RT-PCR). Auranofin and PhPAuCl demonstrated the greatest inhibition of liver fibrosis amongst the tested gold species in human hepatic stellate LX-2 cells.

View Article and Find Full Text PDF

Hepatitis C virus (HCV) replication and assembly occur at the specialized site of endoplasmic reticulum (ER) membranes and lipid droplets (LDs), respectively. Recently, several host proteins have been shown to be involved in HCV replication and assembly. In the present study, we demonstrated the important relationship among osteopontin (OPN), the ER, and LDs.

View Article and Find Full Text PDF

Hepatitis C virus (HCV) infection is a major risk factor for the development of chronic liver disease. The disease typically progresses from chronic HCV to fibrosis, cirrhosis, hepatocellular carcinoma (HCC), and death. Chronic inflammation associated with HCV infection is implicated in cirrhosis and HCC, but the molecular players and signaling pathways contributing to these processes remain largely unknown.

View Article and Find Full Text PDF

Liver fibrosis is a critical wound healing response to chronic liver injury such as hepatitis C virus (HCV) infection. If persistent, liver fibrosis can lead to cirrhosis and hepatocellular carcinoma (HCC). The development of new therapies for preventing liver fibrosis and its progression to cancer associated with HCV infection remains a critical challenge.

View Article and Find Full Text PDF

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. Chronic hepatitis C virus (HCV) infection causes induction of several tumors/cancer stem cell (CSC) markers and is known to be a major risk factor for development of HCC. Therefore, drugs that simultaneously target viral replication and CSC properties are needed for a risk-free treatment of advanced stage liver diseases, including HCC.

View Article and Find Full Text PDF

Hepatitis C virus (HCV) relies on host lipids and lipid droplets for replication and morphogenesis. The accumulation of lipid droplets in infected hepatocytes manifests as hepatosteatosis, a common pathology observed in chronic hepatitis C patients. One way by which HCV promotes the accumulation of intracellular lipids is through enhancing de novo lipogenesis by activating the sterol regulatory element-binding proteins (SREBPs).

View Article and Find Full Text PDF

Aim: To investigate the mechanisms of insulin resistance in human hepatoma cells expressing hepatitis C virus (HCV) nonstructural protein 5A (NS5A).

Methods: The human hepatoma cell lines, Huh7 and Huh7.5, were infected with HCV or transiently-transfected with a vector expressing HCV NS5A.

View Article and Find Full Text PDF

Osteopontin (OPN) is a secreted phosphoprotein which has been linked to tumor progression and metastasis in a variety of cancers including hepatocellular carcinoma (HCC). Previous studies have shown that OPN is upregulated during liver injury and inflammation. However, the role of OPN in hepatitis C virus (HCV)-induced liver disease pathogenesis is not known.

View Article and Find Full Text PDF

Chronic hepatitis C is a lethal blood-borne infection often associated with a number of pathologies such as insulin resistance and other metabolic abnormalities. Insulin is a key hormone that regulates the expression of metabolic pathways and favors homeostasis. In this study, we demonstrated the molecular mechanism of hepatitis C virus (HCV) nonstructural protein 5A (NS5A)-induced metabolic dysregulation.

View Article and Find Full Text PDF

Osteopontin (OPN) is a secreted phosphoprotein, originally characterized in malignant-transformed epithelial cells. OPN is associated with tumor metastasis of several tumors and is overexpressed in hepatocellular carcinoma (HCC) tissue involving HCC invasion and metastasis. Importantly, OPN is significantly up-regulated in liver injury, inflammation, and hepatitis C virus (HCV)-associated HCC.

View Article and Find Full Text PDF

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-β1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-β1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-κB and STAT-3 are involved in TGF-β1 gene expression.

View Article and Find Full Text PDF

Interleukin-1β (IL-1β) is a potent pro-inflammatory cytokine involved in the pathogenesis of HCV, but the sensors and underlying mechanisms that facilitate HCV-induced IL-1β proteolytic activation and secretion remains unclear. In this study, we have identified a signalling pathway leading to IL-1β activation and secretion in response to HCV infection. Previous studies have shown the induction and secretion of IL-1β through the inflammasome complex in macrophages/monocytes.

View Article and Find Full Text PDF

In this study, we demonstrated the molecular mechanisms of TGF-β1 induction as well as proteolytic activation in HCV (JFH-1)-infected cells. Our studies showed the synthesis and secretion of TGF-β1 in HCV-infected cells which was reduced in the presence of Ca(2+) chelators, an inhibitor of mitochondrial Ca(2+) uptake, and antioxidants. We also showed that the expression of HCV NS proteins NS3/4A, and NS5A can induce TGF-β1 by cell-based luciferase assay.

View Article and Find Full Text PDF

Oxidative stress has been implicated in various human diseases, including the pathogenesis of hepatitis C virus (HCV). Previous studies have shown the induction of oxidative stress in cultured cells expressing HCV genes. The transcription factor Nrf2 is known to be activated in response to oxidative stress, but the mechanism of its activation is not clearly understood.

View Article and Find Full Text PDF

Hepatitis C virus (HCV) infection is one of the major causes of chronic hepatitis, liver cirrhosis, which subsequently leads to hepatocellular carcinoma (HCC). The overexpression of the angiogenic factors has been demonstrated in HCC. In this study, we investigated the potential of HCV gene expression in inducing angiogenesis.

View Article and Find Full Text PDF

Hepatic steatosis is a common histological feature of chronic hepatitis C. Hepatitis C virus (HCV) gene expression has been shown to alter host cell cholesterol/lipid metabolism and thus induce hepatic steatosis. Since sterol regulatory element binding proteins (SREBPs) are major regulators of lipid metabolism, we sought to determine whether genotype 2a-based HCV infection induces the expression and posttranslational activation of SREBPs.

View Article and Find Full Text PDF

Oxygen derived species such as superoxide radical, hydrogen peroxide, singlet oxygen and hydroxyl radical are well known to be cytotoxic and have been implicated in the etiology of a wide array of human diseases, including cancer. Various carcinogens may also partly exert their effect by generating reactive oxygen species (ROS) during their metabolism. Oxidative damage to cellular DNA can lead to mutations and may, therefore, play an important role in the initiation and progression of multistage carcinogenesis.

View Article and Find Full Text PDF