title: FLT3 and NPM1 mutations in Chinese patients with acute myeloid leukemia and normal cytogenetics.
abstract: Mutations of fms-like tyrosine kinase 3 (FLT3) and nucleophosmin (NPM1) exon 12 genes are the most common abnormalities in adult acute myeloid leukemia (AML) with normal cytogenetics. To assess the prognostic impact of the two gene mutations in Chinese AML patients, we used multiplex polymerase chain reaction (PCR) and capillary electrophoresis to screen 76 AML patients with normal cytogenetics for mutations in FLT3 internal tandem duplication (FLT3/ITD) and exon 12 of the NPM1 gene. FLT3/ITD mutation was detected in 15 (19.7%) of 76 subjects, and NPM1 mutation in 20 (26.3%) subjects. Seven (9.2%) cases were positive for both FLT3/ITD and NPM1 mutations. Significantly more FLT3/ITD aberration was detected in subjects with French-American-British (FAB) M1 (42.8%). NPM1 mutation was frequently detected in subjects with M5 (47.1%) and infrequently in subjects with M2 (11.1%). FLT3 and NPM1 mutations were significantly associated with a higher white blood cell count in peripheral blood and a lower CD34 antigen expression, but not age, sex, or platelet count. Statistical analysis revealed that the FLT3/ITD-positive group had a lower complete remission (CR) rate (53.3% vs. 83.6%). Survival analysis showed that the FLT3/ITD-positive/NPM1 mutation-negative group had worse overall survival (OS) and relapse-free survival (RFS). The FLT3/ITD-positive/NPM1 mutation-positive group showed a trend towards favorable survival compared with the FLT3/ITD-positive/NPM1 mutation-negative group (P=0.069). Our results indicate that the FLT3/ITD mutation might be a prognostic factor for an unfavorable outcome in Chinese AML subjects with normal cytogenetics, while NPM1 mutation may be a favorable prognostic factor for OS and RFS in the presence of FLT3/ITD.
authors.affiliation: Department of Hematology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Wei-lai
authors.initials: WL
authors.lastname: Xu
authors.forename: Hai-tao
authors.initials: HT
authors.lastname: Meng
authors.forename: Wen-bin
authors.initials: WB
authors.lastname: Qian
authors.forename: Wen-yuan
authors.initials: WY
authors.lastname: Mai
authors.forename: Hong-yan
authors.initials: HY
authors.lastname: Tong
authors.forename: Li-ping
authors.initials: LP
authors.lastname: Mao
authors.forename: Yin
authors.initials: Y
authors.lastname: Tong
authors.forename: Jie-jing
authors.initials: JJ
authors.lastname: Qian
authors.forename: Yin-jun
authors.initials: YJ
authors.lastname: Lou
authors.forename: Zhi-mei
authors.initials: ZM
authors.lastname: Chen
authors.forename: Yun-gui
authors.initials: YG
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Jin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018952:Antigens, CD34 / Q000032:analysis; D019011:Antigens, CD7 / Q000032:analysis; D044466:Asian People / Q000235:genetics*; D003582:Cytogenetics; D005260:Female; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics*; D000090243:Nucleophosmin; D055815:Young Adult; D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics*
chemical_list: D018952:Antigens, CD34; D019011:Antigens, CD7; C000716967:NPM1 protein, human; D009687:Nuclear Proteins; D000090243:Nucleophosmin; C497970:FLT3 protein, human; D051941:fms-Like Tyrosine Kinase 3