Dynein axonemal heavy chain 9 M4374I variation may have an effect on imatinib mesylate resistance in CML

Abstract

Chronic myelogenous leukemia (CML) is a myeloproliferative neoplasm caused by a translocation between the breakpoint cluster region (BCR) and Abelson murine leukemia 1 (ABL1) genes. Tyrosine kinase inhibitors (TKIs) are used in the treatment of CML. TKIs, bind the ABL1 kinase domain of hybrid BCR‑ABL1 protein and inhibit its function. However, resistance can occur due to the pathogenic variations in the ABL kinase domain or BCR‑ABL1‑independent mechanisms. In the present study, genetic variations possibly related to imatinib resistance in CML were explored. A total of five single nucleotide polymorphisms [SNPs; MORN2 rs3099950, PTCRA rs9471966, ANKRD35 rs11579366, dynein axonemal heavy chain 9 (DNAH9) rs1990236 and MAGEC1 rs176037] were investigated in imatinib sensitive and in resistant CML patients. Additionally, sequencing of the ABL1 kinase domain was also performed. The frequency of DNAH9 M4374I (NP_001363.2)/M686I (NP_004653.2) (rs1990236) was found to be significantly higher in the imatinib‑resistant group. However, the other SNPs did not exhibit any statistically significant differences and no new variant was detected in the ABL1 kinase domain. Considering the frequency difference of the DNAH9 rs1990236 between imatinib‑sensitive and imatinib‑resistant groups, DNAH9 gene may play a role in TKI resistance. Due to the limited amounts of literature available on this subject, further studies on DNAH9 and related genes may prove to be beneficial for the elucidation of the association between DNAH9 and TKI resistance. Moreover, further larger studies are required to support the current findings. This may aid in the development of novel treatment protocols for patients with CML with DNAH9 genetic polymorphisms.