Lack of Association Between Human Leukocyte Antigen-E Alleles and Nasopharyngeal Carcinoma in Tunisians

Abstract

Nasopharyngeal carcinoma (NPC), a cancer with a remarkable geographical and worldwide ethnic distribution, has been strongly associated with human leukocyte antigen (HLA) class I genes. The presence of additional HLA risk factors has been suggested by several reports. In the present study, we analyzed the implication of HLA-E gene polymorphisms in NPC susceptibility in Tunisians, a population characterized by an intermediate incidence of NPC with specific clinical features. Peripheral blood DNA was obtained from 185 patients with NPC and 177 matched controls. Genotyping for three single-nucleotide polymorphisms, codon 83Gly/Arg, codon 157Arg/Gly, and codon 107Arg/Gly, was performed using the polymerase chain reaction method. The HLA-E*01:01 and HLA-E*01:03 were the only alleles found among Tunisians. The HLA-E*01:03 allele had a slight increase in patients with NPC (43%) compared with controls (37%), but the difference did not reach a statistical significance. Our results show the lack of association between HLA-E alleles and NPC in the Tunisian population. This is not in agreement with the previous studies, suggesting a potential implication of HLA-E gene polymorphisms in the susceptibility to NPC among populations with high-risk incidence. Our study further supports the dissimilarity of NPC between populations with different NPC incidence.