Detection of p53 Mutant and isochromosome 17q in Myelodysplastic Syndromes and Leukemias / 대한임상병리학회지

ABSTRACT

BACKGROUND: The p53 gene is a tumor suppressor gene situated in the short arm of chromosome 17(in 17p13 band). The p53 mutation is often correlated with the worsening or relapsing of the hematologic malignancies, and the loss of the short arm of chromosme 17 is associated with a p53 mutation on the remaining allele in several hematologic malignancies. In this study, we investigated correlations between cytogenetic rearrangements leading to 17p deletion, the presence of mutant p53 protein and single strand conformational polymorphism analysis of the p53 gene in myelodysplastic syndromes and leukemias. METHODS: In this study, we analyzed 60 patients with different hematologic malignancies, including 26 acute myelogenous leukemia, 16 acute lymphoblastic leukemia, 7 myelodysplastic syndrome, and 11 chronic myelogenous leukemia. Cytogenetic analysis of the bone marrow was performed by using the G-banding method. Mutant p53 protein was detected using a mouse monoclonal antibody, which reacts with mutant p53. The Polymerase chain reaction and the single strand conformational polymorphism analysis(PCR-SSCP) of exons 5 to 8 of the p53 gene were performed on only 20 patients with acute myelogenous leukemia. RESULTS: Only 1(1.7%) out of 61 patients showed a deletion of the short arm of chromosome 17 through isochromosome 17q and mutant p53 protein. This patient with chronic myelogenous leukemia underwent a clinical transition from chronic to blastic phase. But, PCR-SSCP of the p53 gene was not performed on this patient with isochromosome 17q and mutant p53 protein. CONCLUSIONS: Even though analysis of the p53 gene by PCR-SSCP was not fully performed, this report suggests that the frequency of p53 mutant may be rare in Korean patients with myelodysplastic syndromes and leukemias. In addition, further investigation is required for the correlation between immunofluorescence and PCR-SSCP to detect p53 mutations.