MOK overexpression is associated with promoter hypomethylation in patients with acute myeloid leukemia

Overexpression of MAPK/MAK/MRK overlapping kinase (MOK) has been found in various tumors. However, the mechanism underlying MOK upregulation remains unclear. A CpG island was identified in MOK promoter. In this study, we evaluated the expression and methylation status of MOK gene in acute myeloid leukemia (AML). Hypomethylation of MOK promoter was detected in 31.0% (45/145) of AML patients. The degree of MOK hypomethylation was significantly correlated with MOK expression in AML patients. MOK-hypomethylated patients had a trend towards lower WBCs. Receiver operating characteristic curve (ROC) analysis showed a good performance in distinguishing AML patients from controls with an area under the ROC curve (AUC) of 0.820 (P < 0.001). In summary, our results suggest MOK promoter hypomethylation is a common event and contributes to MOK overexpression in AML.