14-bp Insertion/Deletion Polymorphism of the HLA-G gene in Breast Cancer among Women from North Western Iran

Abstract

<b>Background:</b> The human leukocyte antigen-G (HLA-G) gene is highly expressed in cancer pathologies and isone strategy used by tumor cells to escape immune surveillance. A 14-bp insertion/deletion (InDel) polymorphismof the HLA-G gene has been suggested to be associated with HLA-G mRNA stability and the expression ofHLA-G. The aim of present study was to assess any genetic association between this polymorphism and breastcancer among Iranian-Azeri women. Materials and <br/><b>Methods</b>: In this study 227 women affected with breastcancer, in addition to 255 age-sex and ethnically matched healthy individuals as the control group, participated.Genotyping was performed using polymerase chain reaction and electrophoresis assays. The data were compiledaccording to the genotype and allele frequencies, compared using the Chi-square test. Statistical significance wasset at P<0.05. <br/><b>Results</b>: In this case-control study, no significant difference was found between the case and controlgroups at allelic and genotype levels, although there is a slightly higher allele frequency of HLA-G 14bp deletionin breast cancer affected group. However,when the stage I subgroup was compared with stage II plus stage IIIsubgroup of affected breast cancer, a significant difference was seen with the 14 bp deletion allele frequency.The stage II-III subgroup patients had higher frequency of deletion allele (57.4% vs 45.8%) than stage I cases(χ2=4.16, p-value=0.041). <br/><b>Conclusions</b>: Our data support a possible action of HLA-G 14bp InDel polymorphismas a potential genetic risk factor for progression of breast cancer. This finding highlights the necessity of futurestudies of this gene to establish the exact role of HLA-G in progression steps of breast cancer.