scholarly journals Prevalence of FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in de novo acute myeloid leukemia patients categorized according to cytogenetic risk

2009 ◽  
Vol 127 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Everson Augusto Krum ◽  
Mihoko Yamamoto ◽  
Maria de Lourdes Lopes Ferrari Chauffaille
Keyword(s):  
Acute Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Myeloid Leukemia ◽  
Tandem Duplication ◽  
De Novo ◽  
Sao Paulo ◽  
São Paulo ◽  
Cross Sectional ◽  
Internal Tandem Duplication ◽  
Acute Myeloid

CONTEXT AND OBJECTIVE: The mechanism involved in leukemogenesis remains unclear and more information about the disruption of the cell proliferation, cell differentiation and apoptosis of neoplastic cells is required. DESIGN AND SETTING: Cross-sectional prevalence study at the Discipline of Hematology, Hospital São Paulo, Universidade Federal de São Paulo. METHODS: We investigated FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in 40 adult patients with de novo acute myeloid leukemia (AML), categorized according to cytogenetic results, from September 2001 to May 2005. RESULTS: Thirteen patients (32.5%) were classified as presenting the favorable karyotype, 11 patients (27.5%) as an intermediate group, 7 patients (17%) as an undefined group and 9 patients (22.5%) as the unfavorable group. FLT3/ITD+ was found in 10 patients (25%): 3 with FLT3/ITD+ and favorable karyotype; 4 with FLT3/ITD+ and intermediate karyotype; 2 with FLT3/ITD+ and undefined karyotype; and only 1 with FLT3/ITD+ and unfavorable karyotype. Among the patients without FLT3/ITD+, 10 presented favorable karyotype, 8 intermediate, 4 undefined and 8 unfavorable karyotype. The cytogenetic results showed no correlations between FLT3/ITD presence and the prognostic groups (P = 0.13). We found that 2 patients were still alive more than 24 months later, FLT3/ITD+ did not influence the patients' survival rate. CONCLUSION: We found the same frequency of AML with FLT3/ITD+ in both the favorable and intermediate prognosis groups. Only one patient presented AML, FLT3/ITD+ and unfavorable karyotype (the hypothetical worst clinical situation). Therefore, the prognostic advantage of favorable cytogenetics among patients with FLT3/ITD+ remains to be elucidated, for it to be better understood.

FMS-Like Tyrosine Kinase 3 Internal Tandem Duplication and the Patterns of Its Gene Sequence in 207 Chinese Patients With De Novo Acute Myeloid Leukemia

2012 ◽  
Vol 136 (1) ◽  
pp. 84-89 ◽  
Author(s):  
Ling Zhong ◽  
Yong Qian Jia ◽  
Wen Tong Meng ◽  
Xun Ni
Keyword(s):  
Acute Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Myeloid Leukemia ◽  
Tandem Duplication ◽  
De Novo ◽  
Chinese Patients ◽  
Wild Type ◽  
Internal Tandem Duplication ◽  
Tandem Duplications ◽  
Acute Myeloid

Context.—Constitutive activation of the FMS-like tyrosine kinase 3 (FLT3) receptor tyrosine kinase by internal tandem duplication (ITD) has been researched in patients with de novo acute myeloid leukemia (AML). Objective.—To study the patterns of FLT3-ITD in Chinese patients with AML. Design.—A total of 207 patients with de novo AML were enrolled in the study. Genomic DNA was extracted from peripheral blood and polymerase chain reaction was performed. GeneScan was used to analyze the mutant to wild-type ratio. The sequencing of mutated genes was performed to confirm the mutation types and exclude false positives. Results.—A total of 42 cases (20.3%) were associated with mutations. FLT3-ITD was found equally in AML subtypes M1 to M6. The level of the ITD allele was heterogeneous. GeneScan showed that the mutant to wild-type ratio ranged from 0.03 to 3.78 (median, 0.43). Patients with a high ratio had significantly lower cancer remission rates and shorter survival. They also showed distinct clinical features including higher white blood cell counts and higher CD7 and CD56 expression. The length of the duplicated fragment was 26 to 57 bp (median, 43 bp). Twenty-two cases (52%) had simple tandem duplications, while 20 other cases (48%) had an extra interval of 12 to 30 bp before the tandem duplications. A hexanucleotide consisting of GAAAAG was found exclusively in the intervals. Patients with this GAAAAG interval showed better survival. The ITD to wild-type ratio, gene pattern, and CD7 expression status appear to be independent prognostic indices for patients with AML. Conclusion.—Detection of FLT3 mutation is fast, easy, and inexpensive. The mutant to wild-type ratio is helpful for performing detailed risk stratification. DNA sequence analysis is more precise for confirming and evaluating the mutation pattern.

Quizartinib in the treatment of FLT3-internal-tandem duplication-positive acute myeloid leukemia

2019 ◽  
Vol 15 (34) ◽  
pp. 3885-3894 ◽  
Author(s):  
Shilpa Paul ◽  
Adam J DiPippo ◽  
Farhad Ravandi ◽  
Tapan M Kadia
Keyword(s):  
Acute Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Myeloid Leukemia ◽  
Tandem Duplication ◽  
Kinase Inhibitors ◽  
Single Agent ◽  
Tyrosine Kinase Domain ◽  
Missense Mutations ◽  
Internal Tandem Duplication ◽  
Acute Myeloid

FLT3 mutations, characterized by an internal-tandem duplication or missense mutations in the tyrosine kinase domain, are observed in a third of patients with newly diagnosed acute myeloid leukemia. FLT3-ITD mutations are associated with high relapse rates and short overall survival with conventional chemotherapy. Several tyrosine kinase inhibitors targeting FLT3 have been developed in an effort to improve survival and therapeutic options. This review focuses on quizartinib, a second-generation FLT3 inhibitor that has demonstrated efficacy and safety as a single agent and in combination with chemotherapy. We discuss its clinical development as well as its place in the treatment of FLT3-mutated acute myeloid leukemia among the other FLT3 inhibtors currently available and its mechanisms of resistance.

A FLT3 tyrosine kinase inhibitor is selectively cytotoxic to acute myeloid leukemia blasts harboring FLT3 internal tandem duplication mutations

Blood ◽  
2001 ◽  
Vol 98 (3) ◽  
pp. 885-887 ◽  
Author(s):  
Mark Levis ◽  
Kam-Fai Tse ◽  
B. Douglas Smith ◽  
Elizabeth Garrett ◽  
Donald Small
Keyword(s):  
Acute Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Myeloid Leukemia ◽  
Tandem Duplication ◽  
Kinase Inhibitor ◽  
Internal Tandem Duplication ◽  
Flt3 Internal Tandem Duplication ◽  
Study Dose ◽  
Acute Myeloid

Abstract Internal tandem duplication (ITD) mutations of the receptor tyrosine kinase FLT3 have been found in 20% to 30% of patients with acute myeloid leukemia (AML). These mutations constitutively activate the receptor and appear to be associated with a poor prognosis. Recent evidence that this constitutive activation is leukemogenic renders this receptor a potential target for specific therapy. In this study, dose-response cytotoxic assays were performed with AG1295, a tyrosine kinase inhibitor active against FLT3, on primary blasts from patients with AML. For each patient sample, the degree of cytotoxicity induced by AG1295 was compared to the response to cytosine arabinoside (Ara C) and correlated with the presence or absence of a FLT3/ITD mutation. AG1295 was specifically cytotoxic to AML blasts harboring FLT3/ITD mutations. The results suggest that these mutations contribute to the leukemic process and that the FLT3 receptor represents a therapeutic target in AML.

scholarly journals Phase I Study of Quizartinib Administered Daily to Patients With Relapsed or Refractory Acute Myeloid Leukemia Irrespective of FMS-Like Tyrosine Kinase 3–Internal Tandem Duplication Status

2013 ◽  
Vol 31 (29) ◽  
pp. 3681-3687 ◽  
Author(s):  
Jorge E. Cortes ◽  
Hagop Kantarjian ◽  
James M. Foran ◽  
Darejan Ghirdaladze ◽  
Mamia Zodelava ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Phase I ◽  
Myeloid Leukemia ◽  
Tandem Duplication ◽  
Human Study ◽  
Internal Tandem Duplication ◽  
Platelet Recovery ◽  
Acute Myeloid ◽  
Refractory Aml

Purpose FMS-like tyrosine kinase 3–internal tandem duplication (FLT3-ITD) mutations in acute myeloid leukemia (AML) are associated with early relapse and poor survival. Quizartinib potently and selectively inhibits FLT3 kinase activity in preclinical AML models. Patients and Methods Quizartinib was administered orally at escalating doses of 12 to 450 mg/day to 76 patients (median age, 60 years; range, 23 to 86 years; with a median of three prior therapies [range, 0 to 12 therapies]), enrolled irrespective of FLT3-ITD mutation status in a phase I, first-in-human study in relapsed or refractory AML. Results Responses occurred in 23 (30%) of 76 patients, including 10 (13%) complete remissions (CR) of any type (two CRs, three CRs with incomplete platelet recovery [CRp], five CRs with incomplete hematologic recovery [CRi]) and 13 (17%) with partial remissions (PRs). Of 17 FLT3-ITD–positive patients, nine responded (53%; one CR, one CRp, two CRis, five PRs); of 37 FLT3-ITD–negative patients, five responded (14%; two CRps, three PRs); of 22 with FLT3-ITD–indeterminate/not tested status, nine responded (41%; one CR, three CRis, five PRs). Median duration of response was 13.3 weeks; median survival was 14.0 weeks. The most common drug-related adverse events (> 10% incidence) were nausea (16%), prolonged QT interval (12%), vomiting (11%), and dysgeusia (11%); most were ≤ grade 2. The maximum-tolerated dose was 200 mg/day, and the dose-limiting toxicity was grade 3 QT prolongation. FLT3-ITD phosphorylation was completely inhibited in an in vitro plasma inhibitory assay. Conclusion Quizartinib has clinical activity in patients with relapsed/refractory AML, particularly those with FLT3-ITD, and is associated with an acceptable toxicity profile.

Sign in / Sign up

Export Citation Format

Share Document