Hypermethylation of the DAP-Kinase CpG Island Is a Common Alteration in B-Cell Malignancies

摘要: Death-associated protein kinase (DAP-Kinase) is a novel serine/threonine whose expression required for γ interferon-induced apoptosis. A previous study suggested that DAP-Kinase may be lost epigenetically in cancer cell lines, because treatment of several nonexpressing lines with 5-aza-2′-deoxycytidine resulted the DAP-Kinase. Using methylation-specific polymerase chain reaction (MSP), we examined CpG island hypermethylation cancer. Normal lymphocytes and lymphoblastoid are unmethylated 5′ However, primary tumor samples, all Burkitt’s lymphomas 84% B-cell non-Hodgkin’s were hypermethylated island. In contrast, none T-cell lymphoma samples 15% or less leukemia had alleles. U937, an unmethylated, DAP-Kinase–expressing line, was treated interferon underwent apoptosis; however, Raji, fully methylated, only did so when followed by interferon. Our findings tumors suggest gene loss interferon-mediated apoptosis important development malignancies provide promising biomarker B-cell–lineage lymphomas.