title: Genetic association of interleukin-6 polymorphism (-174 G/C) with chronic liver diseases and hepatocellular carcinoma.
abstract: Interleukin-6 (IL-6) is a pleiotropic cytokine which is expressed in many inflammatory cells in response to different types of stimuli, regulating a number of biological processes. The IL-6 gene is polymorphic in both the 5' and 3' flanking regions and more than 150 single nucleotide polymorphisms have been identified so far. Genetic polymorphisms of IL-6 may affect the outcomes of several diseases, where the presence of high levels of circulating IL-6 have been correlated to the stage and/or the progression of the disease itself. The -174 G/C polymorphism is a frequent polymorphism, that is located in the upstream regulatory region of the IL-6 gene and affects IL-6 production. However, the data in the literature on the genetic association between the -174 G/C polymorphism and some specific liver diseases characterized by different etiologies are still controversial. In particular, most of the studies are quite unanimous in describing a correlation between the presence of the high-producer genotype and a worse evolution of the chronic liver disease. This is valid for patients with hepatitis C virus (HCV)-related chronic hepatitis and liver cirrhosis and hepatocellular carcinoma (HCC) whatever the etiology. Studies in hepatitis B virus-related chronic liver diseases are not conclusive, while specific populations like non alcoholic fatty liver disease/non-alcoholic steatohepatitis, autoimmune and human immunodeficiency virus/HCV co-infected patients show a higher prevalence of the low-producer genotype, probably due to the complexity of these clinical pictures. In this direction, a systematic revision of these data should shed more light on the role of this polymorphism in chronic liver diseases and HCC.
authors.affiliation: Unit of Internal Medicine, Biomedical Department of Internal Medicine and Specialties DiBiMIS, University of Palermo, 90127 Palermo, Italy. lydia.giannitrapani@unipa.it
authors.forename: Lydia
authors.initials: L
authors.lastname: Giannitrapani
authors.forename: Maurizio
authors.initials: M
authors.lastname: Soresi
authors.forename: Daniele
authors.initials: D
authors.lastname: Balasus
authors.forename: Anna
authors.initials: A
authors.lastname: Licata
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Montalto
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000276:immunology; D005234:Fatty Liver / Q000235:genetics / Q000276:immunology; D020022:Genetic Predisposition to Disease; D019694:Hepatitis B, Chronic / Q000235:genetics / Q000276:immunology; D019698:Hepatitis C, Chronic / Q000235:genetics* / Q000276:immunology; D019693:Hepatitis, Autoimmune / Q000235:genetics / Q000276:immunology; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008103:Liver Cirrhosis / Q000235:genetics / Q000276:immunology; D008108:Liver Diseases, Alcoholic / Q000235:genetics / Q000276:immunology; D008113:Liver Neoplasms / Q000235:genetics* / Q000276:immunology; D065626:Non-alcoholic Fatty Liver Disease; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6
keywords: Chronic hepatitis; Hepatocellular carcinoma; Interleukin-6; Liver cirrhosis; Single nucleotide polymorphisms