Chromosome 17 abnormalities and mutation of the TP53 gene: correlation between cytogenetics, flow cytometry and molecular analysis in three cases of chronic myeloid leukemia

Abstract

Alterations involving the short arm of chromosome 17 (17p) during the progression of chronic myeloid leukemia (CML) have been described. This chromosomal region contains the tumor suppressor gene TP53 that may be an important factor in the evolution of this disease. In this study, we used flow cytometry and western blotting to assess p53 protein expression and single stranded conformational polymorphism to examine TP53 gene alterations in three patients with CML who showed alterations in 17p. Only the case with del(17)(p11) had p53 expression positive by flow cytometry and an abnormal migration pattern by SSCP analysis. The importance of the correlation between the results obtained with these techniques, as well as the clinical course of the patients, are discussed.

O Impacto das Alterações Cromossômicas Adicionais em Resposta ao Mesilato de Imatinibe na Leucemia Mielóide Crônica

“…Clonal evolution after treatment was observed by us and others (Cortez et al 18 In our study 10.4% of the patients developed clonal cytogenetic evolution during imatinib, similar to the results presented by Schoch et al 15 (12.9%). The most frequent chromosomal abnormality during imatinib therapy was trisomy 8, a finding consistent with other studies 2,17 .…”

“…Thus, the acquisition of a second Ph chromosome, trisomy 8, isochromosome 17, and trisomy 19 constitute the main routes, accounting for approximately 70% of cases 3 . In addition, molecular abnormalities such as TP53 mutations can arise 15 .…”

Polimorfismo do gene tp53 no códon 72 em pacientes com suspeita de LMC

“…Esses achados sugerem que mutações no gene TP53 são um segundo evento na progressão da LMC. 11 Estes dados sugerem a realização de um estudo mais extenso sobre a p53 em LMC, englobando alterações citogenéticas, polimorfismos, expressões gênicas.…”