Application Of Real-time PCR To Detect PML-RARα Fusion Gene In Acute Premyeloid Leukemia

Purpose:Acute promyelocytic leukemia(acute promyelocytic leukemia,APL)is one kind of Leukemia,accounting for adult acute myeloid leukemia 10%,Most common chromosome t (15; 17) (q22; q21) chromosome shifting, the masculine gender rate approximately composes 98%. At last APL PML promyelocytic leukemia gene and RARαgene weigh a row and finally forming PML-RARαfusion gene. Combined treatment with all-transretinoic acid(ATRA) and arsenic trioxide(arsenic trioxide,ATO As2O3)is highly successful in APL,providing long-term complete remissions and apparent cure rates to approximately 70%. However disease relapse has been a major contributor to treatment failure and overall survival in patients,and the root cause of relapse is residual leukemia cells in patient,namely,acute leukemia minimal residual disease(MRD).A real-time quantitative reverse transcript polymerase chain reaction(RQ-PCR)for detection of PML-RARαfusion gene out-come in patients with acute promyelocytic leukemia and to explore the relationship between the expression level of PML-RARa fusion gene transcript and the clinical status or efficacy of the therapy in APL.This study was purposed to establish a real-time quantitative reverse transcript polymerase chain reaction(RQ-PCR)for detection of PML-RARαfusion gene transcrips in patients with acute promyelocytic leukemia and to explore the relationship between the expression level of PML-RARa fusion gene transcript and the clinical status or efficacy of the therapy in APL,to explore relationship APLsubtype and proqnosis.Method :PML-RARαfusion gene movement was detected by RQ-PC R in induction therapy. APL which initially governs after 32 examples the patient treats, the alleviati- on, consolidated and maintenance treatment period every 3 months examine a dynamic monitor PML-RARαfusion gene.Result : 1.In the long-term follow-up of 28 cases who achieved complete (CR),one case relapsed in molecular level, who relapsed after 3 months of CR1 and achieved CR2 after induction therapy.However,molecular and hematological relapse occured again 3months later after CR2 and achieved CR3 after one induction thera- py. Three cases relapsed after 3 and 4 months and achieved CR2 by one induction treatment, and survived for 24 months untile the end of follow-up. 2. In the 28 cases who fusion gene positive,19cases are L type,9 are S type,by the induce treatment of ATRA or ATRA+DNR 18 L type cases reach CR, 6 S typef reach CR, (P<0.05) suggesting a beneficial role .In the L type,one case relapse,another one dead,however,in the S type ,three cases relapse,two cases dead, (P>0.05) suggesting a significance role. Conclusion :1.RQ-PCR assay for detection of PML-RARαshould be performed regularly during CR period to monitor molecular relapse. Hematological relapse could be potentially averted by modification treatment according to monitoring PML-RARα. The expression levels of clinical disease progression with the same therapeutic relationship can be used to monitore PML-RARαfusion gene copy number dynamically,is useful for monitoring minimal residual disease of leukemia,the evaluation to determine the efficacy and prognosis.2.From this study we can find :APL with S and L type through same threatment suggest a beneficia role in CR rate but significance role in dead rate.