Infant Leukemia Fusion Gene Screening And Preliminary Study Of Its Clinical And Biological Characteristics

Background:Infant leukemia is relatively rare type of leukemia children,Low incidence. With onset nasty, short duration, the incidence is increasing. With the advances in molecular biology level to risk stratification for the individualized treatment plan for clinical guidance,leukemia in children five years has been significantly improved disease-free survival.However, due to IL lack of large sample report and track system, the therapeutic effect is poor. Therefore, it is important to exlpore the mechanism of infant leukemia and further improve their survival.Objective:Screening MLL-AF4, BCR-ABL, E2A-PBX1, TEL-AML1, HOX11, HOX11L2, CALM-AF10, SIL-TAL1, E2A-HLFshower series9kinds of fusion gene and MLL-AF9. STAT5b/P1P1L/PRK/NUMA/NPM-RARa、BCR-ABL、AML1-ETO、 PML-RARa、CBFβ-MYH11、DEK-CAN、PLZF-RAR、NPM-MLF1myeloid13kinds of fusion gene in children with incipient IL expression in bone marrow, and preliminary clinical data of children with positive analysis, the paper mainly discusses the MLL gene rearrangement (mixed-lineage-leukemia-rearranged, MLL-R) with IL treatment and prognosis.Methods:1.55cases of children with incipient IL take joint multiple seruice (multiplex nested) real-time quantitative PCR (real time policy PCR, RT-PCR) method and Fluorescence in situ hybridization (Fluorescence in situ hybridization, FISH) fusion gene detection technology (n=55).The positive test results of children take dynamic monitoring.2. The infant acute lymphoblastic leukemia (infant acute lymphoblast leukemia, IALL) and myelogenous leukemia baby (infant acute myeloid leukemia, IAML) children were divided into the MLL-R positive group and negative group, by analyzing the composition of age, sex, white blood cell count, and remission rate and other indicators, discusses the MLL-R genes effect on the treatment and prognosis. Results:55cases in children with IL,34cases (61.8%) were detected positive, MLL R positive, a total of30cases, E2A-PBX1fusion gene positive in2cases, P16tumor suppressor gene mutation in1case, CBF beta/MYH11fusion gene positive in1case. After diagnosis, a total of3cases of give up, including1case of MLL-R positive for acute drench grain of hybrid leukemia;1case of CBF beta/MYH11fusion gene positive IAML children;1case of fusion gene negative JMML of children. MLL-R positive30cases:in30cases of IALL MLL-R positive17cases,56.7%(17/30), treatment of17cases of MLL-R positive dynamic detection in children:4cases of continuous positive, death;13cases after induction therapy turns negative, among them6cases during treatment emersion positive, recurrence; To give up,2cases of consolidation treatment for recurrent positive review reiteration, children with death;5cases of CR). In23cases of children with IAML MLL-R positive12cases, accounting for52.2%;12cases of MLL-R positive dynamic monitoring:1case of continuous positive, recurrence of death;11cases turn induction therapy of rendering (1case of consolidation treatment of give up, and death;10cases of CR). Acute drench grain of hybrid leukemia in1case, testing MLL-R is positive, choose to give up after diagnosis, follow-up of children have died. E2A-PBX1fusion gene positive in2cases,2cases of E2A CR/PBX1through intensive treatment, during the review of the negative. P16tumor suppressor gene mutation in1case, children after induction of CR review were negative.CBF beta/MYH11fusion gene positive in1:after diagnosis:give up, lost to follow-up.The52cases of children with treatment of IL respectively according to the results of the MLL-R detection is divided into MLL-R positive group and negative group.30cases of IALL MLL-R positive17:six deaths,6cases of recurrence,5cases of CR, complete response rate was29.4%; MLL-R negative group of10cases,1case died,9cases of CR, complete response rate was90%. IALL MLL-R positive and negative patients in complete remission rate (P<0.05,P=0.03).22cases IAML MLL-R positive in12cases,2cases died,10cases of CR, complete response rate was83.3%; MLL-r negative group of10cases,3cases died,7cases of CR, complete response rate was70%. IAML MLL-R in positive and negative differences complete response rate between patients with no statistical significance (P>0.05,P=0.47).Conclusions:1. The fusion gene screening can guide IL risk stratification and prognosis, and provide the basis for individualized treatment.2. In children with IALL:MLL-R positive rate was56.7%, the clinical manifestations of the high white blood cells, more much viscera infiltrates, central nervous system leukemia, etc. Comparative study found that expressing positive complete response rate is low, prompt with poor prognosis.3. In children with IAML:MLL-R positive rate was52.2%, the comparison study found that patients with positive and negative complete response rate, there was no significant difference expression was not prognosis factors.4. The MLL-R of IL positive were still testing after CR for positive hints with poor prognosis.5. Low E2A and detection of P16tumor suppressor genes expression, to enhance the intensity of chemotherapy, good response to treatment, prognosis is good.