HLA-DRB1*03:01 AND HLA-DRB1*11:01 ALLELES ARE ASSOCIATED WITH AN INCREASED RISK OF BREAST CANCER IN ITALIAN INDIVIDUALS

Breast cancer (BC) is one of the most common and malignant disease among women with almost one million cases newly diagnosed every year. Hormonal and environmental factors could be involved in the presentation of BC. There is also evidence that genetic factors may favour or interfere with the occurrence of BC. HLA class II antigens are one of them. They are considered to be relevant in tumor surveillance since they present peptides derived from tumor associated antigens to T lymphocytes inducing an anti-tumor immune response. Thereby, these molecules may play an important role in the immune response to breast cancer tumor associated. However, the role of HLA-class II antigens genotype on the pathogenesis of BC is not completely understood. In this study, we investigate the significance of HLA DRB1 alleles on the occurrence of BC in Italian population. 68 patients (Female= 67, Male=1) with pathologically proven BC enrolled at the Tor Vergata Hospital (PTV) in Rome .We performed DRB1 genotype by sequence-based typing (SBT) on DNA isolate from peripheral white blood cells obtained from 68 Italian patients and a group of 297 healthy subjects. We evaluate 28 alleles of DR gene including the frequency HLA-DRB1*03:01 and of HLA-DRB1*11:01. For statistical analysis we used Fisher's exact test in addition to x2, for 2x2 tables, as appropriate. Compared to normal individuals, we found that HLA-DRB1*03:01 (P c= 0.01, OR = 3.5) and of HLA-DRB1*11:01 (P c <0.0001, OR=5.02) genotypes were greatly associated with BC. In contrast, we did not find any HLA-DRB1 genotypes showing a protective role from BC . These findings imply a link between HLA-DRB1*03:01 and of HLA-DRB1*11:01 and the occurrence of BC . Importantly, the implementation of such a non invasive, genetic screenings may help health personal to identify women at risk of developing BC.