205例急性髓系白血病患者IDH1基因突变的检测及其临床意义分析

Detection of Isocitrate Dehydrogenase 1 Gene Mutation in 205 AML Patients and Its Clinical Significance

本研究检测205例急性髓系白血病(AML)患者IDH1基因R132突变并探讨其临床特征。提取205例成人AML患者初发时外周血或骨髓单个核细胞基因组DNA,通过PCR的方法分别扩增IDH1基因的第4号外显子后进行测序比对。结果发现,205例AML患者中9例有IDH1基因R132突变,突变率4.39%,R132H型突变6例,R132L,R132G,R132S突变各1例,其中5例为AML-M2型白血病,与其他类型比较有统计学意义(P=0.002);9例患者血小板中位数45.5×109/L,低于IDH1为野生型患者(P=0.003);IDH1突变患者在性别、年龄、初发白细胞计数、血红蛋白水平及骨髓幼稚细胞比例上与IDH1为野生型的患者相比无明显差异(P>0.05)。9例患者中4例为正常核型,在71例CN-AML中的突变率为5.63%;合并FLT3/ITD突变5例,与IDH1为野生型患者比较有明显差异(P=0.017);合并c-kit突变的1例;合并NPM1突变2例;无合并CEBPA突变者,与野生型比较有明显差异(P=0.031);无合并WT1突变者。结论:IDH1基因R132突变在中国人AML中发生率为4.39%,以R132H突变为主,易在AML-M2型中发生,具有低血小板计数,易合并FLT3/ITD突变,不易合并CEBPA突变等特征。

This study was purposed to detect the mutation of isocitrate dehydrogenase 1 （IDH-1） gene in patietns with acute myeloid leukemia （AML） and to explore its clinical significance. The genomic DNA was extracted from mononuclear cells （MNC） of bone marrow or peripheral blood in 205 adult AML patients, the exon 4 of IDH1 gene was amplified by PCR, then the sequencing and comparison were performed. The results showed that IDH1 mutation was de- tected in 9 （4.39%） of 205 AML patients. There were 6 cases of R132H mutation, 1 of R132L mutation, 1 of R132G mutation and 1 of R132S mutation. Significantly more IDH1 aberrations were detected in AML-M2 （ P = 0.002） than other types. And the 9 patients with IDH1 mutation were characterized by low platelet count which was lower than pa- tients with wild type IDH1 （ P = 0. 003 ）. IDH1 mutation combined with FLT3/ITD mutation was found in 5 cases, c-kit mutation in 1, NPM1 mutation in 2, and IDH1 mutation with CEBPA or WT1 mutation was not found, which revealed a significant interaction between IDH1 mutation and the FLT3/ITD positive genotype or the CEBPA wild-type. IDH1 mu- tation were detected in 4 of 71 （5.63%） CN-AML. There was no significant difference of IDH1 mutation incidence be- tween the normal and abnormal karyotypes. It is concluded that the rate of IDH1 mutation was 4.39% in Chinese AML patients. IDH1 mutation is significantly associated with AML-M2, lower platelet counts in peripheral blood, FLT3/ITD mutation and CEBPA wild-type, but not with age, white blood cell count in peripheral blood, karyotype, NPM1, c-kit or WT1 mutation.