The Clinical Study Of MLL-AF6、MLL-AF9 And MLL-AF10 In Acute Myeloid Leukemia

Objective Through analysed the clinical characteristic of patients with MLL-AF6,MLL-AF9 and MLL-AF10 fusion gene, we are aim to investigate the role of MLL-AF6,MLL-AF9 and MLL-AF10 fusion gene in the incidence of acute myeloid leukemia.Methods We analyzed the clinical and laboratory data of patients with acute leukemia and select acute myeloid leukemia patients with MLL-AF6, MLL-AF9, MLL-AF10 fusion gene as a clinical observation object. By using multiple nested reverse transcription- polymerase chain reaction (RT-PCR),we detected the dynamic change of the MLL-AF6,MLL-AF9 and MLL-AF10 fusion gene and analyzed the relationship between the clinical characteristic, the immune phenotype, cytogenetics, complete remission rate after initial induction therapy,overall survival rate, the effect hematopoietic stem cell transplantation and the prognosis of the patients.Results 1) From February 2008 to January 2015,827 patients were diagnosed with acute leukemia for the first time, including 499 acute myeloid leukemia patients, and there are 13 acute myeloid leukemia patients with MLL-AF-6 fusion gene,17 acute myeloid leukemia patients with MLL-AF-9 fusion gene,11 acute myeloid leukemia patients with MLL-AF-10 fusion gene.2) Acute myeloid leukemia patients with MLL-AF-6 fusion gene, MLL-AF-9, MLL-AF-10 account for 1.6%(13/827)、2.1%(17/827)、1.3%(11/827) of AL respectively,and 2.6%(13/499)、3.4%(17/499)、2.2%(11/499) of AML respectively.3) According to FAB classification, all MLL-AF6, MLL-AF9, MLL-AF10 fusion gene-positive AML patients can be classified into Mo 3case 7.3%(3/41), M1 5 case 12.3%(5/41),M2 7 cases 17.1%(7/41), M4 10 cases 24.4%(10/41), M5 16 cases 39.0%(16/41), M4/M5 accounting for 63%(26/41).4) Among 41 patients,23 patients with white blood count more than 50×109/L,12 patients with white blood count more than 100×109/L,25 patients with Liver and spleen lymph node enlargement. Cell surface antigen CD33 90.2%(37/41)、CD34 70.7%(29/41)、CD15 70.7%(29/41)、CD11b 68.2%(28/41)、CD64 53.7%(22/41)、 CD14 46.3%(19/41)、CD13 34.1%(14/41)、CD117 29.2%(12/41) are high expressed.5) Among 41 patients, the CR rate after the first induction therapy is 63.4%(26/41), the overall survival is 39.0%(16/41), after the follow up,5 patients still survive among 23 patients who received chemotherapy alone, and the survival rate is 21.7% (5/23),the average survival time is 17.1 months,7 patients recurrence within half a year after CR; the recurrence rate is 53.8%(7/13); 11 patients still survive among 18 patients who received hematopoietic stem cell transplantation, and the survival rate is 61.1%(11/18), the average survival time is 24.7 months,5 patients recured within half a year after CR; the recurrence rate is 38.5%(5/13)。6) We used multiple nested reverse transcription-polymerase chain reaction (RT-PCR) detected the dynamic change of the MLL-AF6,MLL-AF9 and MLL-AF10 fusion gene of 41 patients before and after drug treatment, bone marrow transplantation.Fusion gene expression of 14 patients were still negative after treatment,27 patients were not still negative after treatment, the fusion gene expression in 2 patients with still positive and negative alternation,10 patients became still negative after positive and negative alternation. Results of the 12 patients, there are 7 cases who received chemotherapy alone recured within half a year after CR, and fusion gene expression of them became positive before recurred. There are 5 cases who received hematopoietic stem cell transplantation recured within half a year after CR, and fusion gene expression of them became positive before recurred. Fusion gene expression of 15 patients were still positive after treatment (Including 2 acute myeloid leukemia patients with MLL-AF-6 fusion gene lost to follow-up)Conclusions1) The incidence of the expression of MLL-AF6、MLL-AF9 and MLL-AF10 fusion gene in AML among AL is low.2) The incidence of AML patients with MLL-AF6, MLL-AF9 and MLL-AF10 fusion gene rearrangement in M4/M5 patients is high.3) AML patients with MLL-AF6, MLL-AF9 and MLL-AF10 fusion gene can surface express antigen related to hematopoietic stem/progenitor cells and mononuclear system related.4) AML patients with MLL-AF6, MLL-AF9 and MLL-AF10 fusion gene were often accompany with hyperleukocytosis, organ infiltration, worse therapeutic effects, high recurrence rate and poor prognosis.5) Hematopoietic stem cell transplantation can improve the prognosis of patients and prolong patient’s survival time.6) The dynamic change of fusion gene before and after treatment and bone marrow transplantation by using multiple nested reverse transcription-polymerase chain reaction (RT-PCR), what will help us to judge the recurrence and prognosis of patients in a certain extent.