The Significance Of Id4 Gene Methylation In Hematological Malignances

Epigenetic alternations regulate gene expression by affecting gene transcription, which based on DNA methylation. Aberrant CpG island methylation in the 5' regulatory regions of genes is well-categorized epigenetic change in most tumors, associated with the silencing of gene expression and plays an important role in tumorigenesis.Inhibitor of DNA binding 4 (Id4) is a kind of suppressor of DNA binding. With a series of researches in a mouse model of cancer, Id4 gene has been identified as a new putative tumor-suppressor by Professor Yu Li.Based on the research work of Professor Yu, we detected the methylation status of Id4 gene in peripheral blood or bone marrow samples from leukemia, myelodysplastic syndrome, multiple myeloma, non-Hodgkin's lymphoma (NHL) patients and health donors. Methylation status of Id4 gene were different in health donors and hematological malignances: It was unmethylated in health donors, while methylated in most of these hematological malignance patients. So we assumed that the methylation of Id4 gene might be a trigger in tumorigenesis of hematological malignances.Id4 gene was found methylated in some NHL patients with "normal" morphological bone marrow, who turned to be leukemias in a short period. While none of the NHL patients without Id4 gene methylation was found turning to be leukemias.Minimal residual disease (MRD) is one of the reasons of leukemia relapse. It is regarded as a guide for leukemia treatment and prognosis evaluation. Individual treatment is based on identifying MRD in different patients and distinguishing the leukemia cells from normal cells. But until today, no perfect MRD guideline appeared.