Molecular Typing of Human Leukocyte Antigen-Class I (HLA-A, HLA-B) & Human Leukocyte Antigen-Class II (HLA-DR) in Carcinoma Cervix and Its Association with Staging

Cervical carcinoma is the 4th most common cancer worldwide and the most common causative agent is Human Papilloma Virus (HPV). HUMAN LEUKOCYTE ANTIGEN (HLA) are cell surface glycoproteins that play critical roles in cell mediated antitumor immune responses, necessary for the presentation of peptide antigens to cytotoxic T lymphocytes (CTLs) and for the immune regulatory activity exerted by NK cells. HLA Class-I & Class-II genes are highly polymorphic as it provides resistance to potential pathogens by binding and presenting antigenic peptides. Presence of HLA molecules that binds HPV antigens with high affinity might confer a protective effect. Presence of HLA molecules that do not recognize and bind a wide variety of HPV antigens might be associated with the susceptibility of cervical cancer. It is widely accepted that total or partial loss of HLA class I molecules on tumor cells was one of the main mechanisms of tumor escape. In this study an attempt was made to see the association of HLA class I & II alleles in carcinoma cervix.

The aim of this study was molecular typing of HLA-Class I (HLA-A, HLA-B) & Class II (HLA-DR) alleles in carcinoma cervix patients and to compare molecular types of HLA Class I (HLA-A, HLA-B) & Class II (HLA-DR) alleles in carcinoma cervix patients with the healthy control group.

It was a prospective case control study conducted in a tertiary care center which includes 60 cases and controls respectively. All the patients diagnosed with invasive cervical carcinoma in a period of two years were part of the study. 2 ml of blood in EDTA tube was also collected from all the cases along with a healthy donor for HLA typing.

Out of 60 patients in each group HLA-DRB1*11 was found to be statistically significant in cases and, HLA-A*11, HLA-A*24, HLA-B*44, HLA-B*52, HLA-DRB1*14 & HLA-DRB1*15 alleles were found to be statistically significant in controls (p value < 0.05). When FIGO staging was applied, it was observed that most of the cases were in Stage III (56%) followed by Stage II (30%). Stage I & Stage IV comprised 7% each. However, no correlation was found with HLA-DRB1*11 & staging as the p value was not significant (p value = 0.06).

The molecular typing of HLA CLASS I and II alleles provide evidence in the cervical carcinoma pathogenesis and it might help in developing newer treatment strategies.