[Prevalence and clinical significance of FLT3 internal tandem duplication mutation in acute leukemia].Zhonghua Xue Ye Xue Za Zhi. 2004 Jul; 25(7):393-6.ZX
To evaluate the prevalence of FLT3 mutation-internal tandem duplication in acute leukemia (AL) patients and its significance.
Genomic DNAs from 194 cases of AL were screened by polymerase chain reaction (PCR) and gel electrophoresis for FLT3-ITD mutations.
FLT3-ITDs were found in 37 (25.9%) of 143 de novo acute myeoloid leukemia (AML) patients, including 10/53 of M(2), 15/40 of M(3), 4/20 of M(4) and 8/23 of M(5). Significantly more FLT3 aberrations were found in AML M(3) and M(5) (P < 0.05). No FLT3-ITD was found in 25 acute lymphoid leukemia (ALL), 2 acute hybrid leukemia, 17 myelodysplastic syndromes and 7 chronic myelogenous leukemia in blast crisis. Sequence analysis of 5 cases with abnormal PCR electrophoretic patterns revealed that the ITDs were located within exon 14 from 21 bp to 60 bp, in 3 cases the ITD was a simple tandem duplication, and in 2 cases the ITD was tandem duplication with insertion, but all of the above ITD did not altered the FLT3 reading frame. FLT3-ITD was associated with a higher peripheral white cell count (P < 0.05) and a lower complete remission rate (P < 0.05), and was more prevalent in patients with normal karyotype (P < 0.05).
FLT3-ITD mutation occurs with a significant percentage in AML M(3) and M(5) patients. Sequences of the mutants are in frame mutation. FLT3-ITD mutation was associated with a higher peripheral white cell count and a lower complete remission rate.