Human leukocyte antigen-B phenotype and minimal residual disease in chronic myeloid leukemia patients treated with imatinib: Is there an association?

Abstract

Background: Human leukocyte antigen (HLA) phenotype is a prognostic marker of cancer immunotherapy, and the expression profile of its alleles is associated with therapeutic rate. Therefore, there is the likelihood of a relationship between HLA phenotype and minimal residual disease (MRD) in chronic myelogenous leukemia (CML) patients treated with imatinib. The goal of this study was to assess the relationship between the expressions of HLA-B7, 8, 27, 5, and 51 molecules with MRD in CML patients who were treated with imatinib for the first time. Materials and Methods: Blood samples were collected from 33 CML patients who were subject to imatinib therapy for at least 6 months. The expressions of HLA-B molecules were evaluated using standard lymphocytotoxicity technique and MRD was measured by real-time polymerase chain reaction technique. Results: No significant association was found between the expressions of HLA molecules with MRD nor white blood cell, hemoglobin, and platelet counts (P > 0.05). However, CML patients expressing HLA-B5 and 51 molecules were more likely to show optimal response in imatinib therapy. Conclusion: We conclude that HLA-B5 and 51 molecules may have independent prognostic values in imatinib-treated CML patients, which suggests that they could be a prognostic marker for this disease. Nevertheless, investigation of HLA-B5 and 51 molecules in large-scale studies can be helpful in determining the true prognostic value of these molecules in predicting response rates to imatinib therapy among CML patients.