The Impact of HLA-G 3'UTR Polymorphisms in Breast Cancer in a Tunisian Population.

Human leukocyte antigens G and E (HLA-G and HLA-E) are nonclassical major histocompatibility complex (MHC) class I molecules. These molecules play an important role in immune surveillance by inhibiting natural killer and cytotoxic T cells responsible for immune escape. The expression of HLA-G and HLA-E has been associated with several diseases including tumor. The main objective of the study is to evaluate the impact of three HLA-G 3'UTR potential polymorphisms: +3187 A >G (rs9380142), +3142G>C (rs1063320), +2960 14-base pair (bp) Insertion/Deletion (Ins/Del) (rs66554220), and the HLA-E*01:01/01:03 A >G (rs1264457) polymorphism in Tunisian breast cancer population. A total of 355 patients and 381 controls were genotyping for HLA-G and HLA-E polymorphisms using a Taq Man assay. +3142C allele and +3142C/C genotype were significantly associated with increased risk of breast cancer (p=0.00002; OR=1.58; 95% CI=27-1.97) (49% versus 35%; p =0.0001; OR=1.79; 95% CI=1.32-2.44). In addition, Del allele and the homozygous state for Del/Del genotype confer a risk for breast cancer (52% versus 45%, p =0.006; OR=1.33, 95% CI=1.08-1.64) (28% versus 22%, p =0.039; OR=1.43, 95% CI=0.90-2.25). However, no statistical significant differences were reported for HLA-G+3187 A >G and HLA-E variations and breast cancer in a Tunisian population.The found results indicate that HLA-G may play an important role in the breast cancer.