title: Variation of the killer cell immunoglobulin-like receptors and HLA-C genes in nasopharyngeal carcinoma.
abstract: Nasopharyngeal carcinoma (NPC) is an Epstein-Barrvirus (EBV)-associated malignancy. Previous studies have shown that NPC is associated with specific human leukocyte antigen (HLA) alleles which function in adaptive immunity to present viral and other antigens to the immune system. The role of innate immunity in NPC development is unknown. To determine whether innate immunity is associated with NPC, a case-control study was conducted among 295 Taiwanese NPC cases (99% EBV seropositive) and 252 community controls (29% EBV seropositive). Using high-resolution genotyping, we evaluated the variation of HLA class I alleles and killer cell immunoglobulin-like receptor (KIR) alleles. Located on the surface of natural killer (NK) cells and a subset of T cells, inhibitory KIRs diminish NK cytolysis of target cells upon binding to their HLA class I ligands and activating KIRs are thought to stimulate NK destruction of target cells. Our results suggest that an increasing number of activating KIRs may be associated with increasing NPC risk, particularly in individuals seropositive for anti-EBV antibodies known to be linked to NPC susceptibility (P(trend) = 0.07). Among EBV-seropositive individuals, carriers of > or =5 activating KIRs had a 3.4-fold increased risk of disease (95% confidence interval, 0.74-15.7) compared with individuals with no functional activating KIRs. In contrast, there was no clear evidence of risk associated with increasing numbers of inhibitory KIRs. When evaluating HLA-Cw alleles, we observed that carriers of HLA-Cw*0401 alleles were at a significantly reduced NPC risk (odds ratio, 0.46; 95% confidence intervals, 0.23-0.92), an effect that could not be explained by linkage disequilibrium with other NPC-associated HLA alleles. Our results suggest that KIR-mediated activation may be associated with NPC risk. As this finding is consistent with a recent report examining cervical cancer, a malignancy caused by human papillomavirus, the data raises the possibility that KIRs, and more generally innate immunity, may be involved in the pathogenesis of viral-associated cancers.
authors.affiliation: Hormonal and Reproductive Epidemiology Branch, National Cancer Institute, 6120 Executive Boulevard, Room 7101, Bethesda, MD 20853, USA. kovacicm@mail.nih.gov
authors.forename: Melinda
authors.initials: M
authors.lastname: Butsch Kovacic
authors.forename: Maureen
authors.initials: M
authors.lastname: Martin
authors.forename: Xiaojiang
authors.initials: X
authors.lastname: Gao
authors.forename: Tatyana
authors.initials: T
authors.lastname: Fuksenko
authors.forename: Chien-Jen
authors.initials: CJ
authors.lastname: Chen
authors.forename: Yu-Juen
authors.initials: YJ
authors.lastname: Cheng
authors.forename: Jen-Yang
authors.initials: JY
authors.lastname: Chen
authors.forename: Raymond
authors.initials: R
authors.lastname: Apple
authors.forename: Allan
authors.initials: A
authors.lastname: Hildesheim
authors.forename: Mary
authors.initials: M
authors.lastname: Carrington
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000235:genetics* / Q000276:immunology; D016022:Case-Control Studies; D005260:Female; D005805:Genes, MHC Class I; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000235:genetics* / Q000276:immunology; D011971:Receptors, Immunologic / Q000032:analysis*; D012307:Risk Factors
chemical_list: D011971:Receptors, Immunologic