Quantitative measure of c-abl and p15 methylation in chronic myelogenous leukemia : biological implications

• Published in: Blood 2000-05, Vol.95 (9), p.2990-2992
• Main Authors: NGUYEN, T. T, MOHRBACHER, A. F, TSAI, Y. C, GROFFEN, J, HEISTERKAMP, N, NICHOLS, P. W, YU, M. C, LÜBBERT, M, JONES, P. A
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blast Crisis; Carrier Proteins - genetics; Cell Cycle Proteins; Cyclin-Dependent Kinase Inhibitor p15; Cyclin-Dependent Kinase Inhibitor p16; DNA Methylation; Genes, abl; Genes, Tumor Suppressor; Hematologic and hematopoietic diseases; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive - blood; Leukemia, Myelogenous, Chronic, BCR-ABL Positive - genetics; Leukemia, Myelogenous, Chronic, BCR-ABL Positive - pathology; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Medical sciences; Promoter Regions, Genetic; Proto-Oncogene Proteins c-abl - genetics; Tumor Suppressor Proteins
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.v95.9.2990.009k08_2990_2992

We used a sensitive, quantitative bisulfite PCR assay, methylation sensitive single nucleotide primer extension (Ms-SNuPE), to measure methylation of the 5' CpG islands of c-abl and p15 in chronic myelogenous leukemia (CML) patients during progression. We found that the Pa promoter of c-abl was methylated in 81% (17/21) of the white blood cells (WBCs) of CML patients, which correlates with previous reports. In contrast, WBCs from healthy donors, acute myelogenous leukemias, acute lymphocytic leukemias, and myelodysplastic syndromes were unmethylated at the c-abl Pa promoter locus. We also observed p15 hypermethylation in 24% (8/34) of CML cases. Methylation of the p15 but not c-abl Pa promoters was associated with CML progression (P = 0.047 vs 0.46), and the two events were independently acquired. We conclude that de novo methylation of c-abl and p15 both occur in CML, and analysis of DNA methylation changes using the bisulfite-based MS-SNuPE assay allows both a sensitive and quantitative assessment of these molecular events compared to other methods currently utilized. (Blood. 2000;95:2990-2992)