Expression Of PRAME Gene In Acute Leukemia And Its Clinical Significance Compared With FLT3 Gene

SummaryModern chemotherapy regimens inducing remission of acute leukemia was significantly increased, but the relapse of leukemia after reaching complete remission of bone marrow is still one of the hinder long-term disease-free survival in patients (DFS) of the main reasons. Studies found that relapse of leukemia and minimal residual disease is closely related. Minimal residual disease is the clinical remission of leukemia patients can be detected in vivo micro-leukemia cells.The sensitivity of traditional morphological lower standards in clinical remission (bone marrow blast cells<5%), and can not accurately reflect the patient load of residual leukemia cells in vivo, so chemotherapy and intensity of development often depends on the experience of clinicians, there is insufficient or excessive chemotherapy question. So looking for high sensitivity and specificity, rapid and effective, reproducible MRD detection means and targets, is very important. In this study, real-time quantitative RT-PCR detected preferentially expressed antigen of melanoma (PRAME) gene expression in acute leukemia patients, the clinical significance of the gene and its target as the feasibility of MRD detection.Materials and Methods:Study of 119 patients with acute leukemia, both in Henan Province People's Hospital in-patient or patient newly diagnosed patients, diagnostic criteria established by reference to standard FAB Cooperative Group. 71 patients were male (59.7%), female 48 cases (40.3%), median age 30 years (2-78 years); including AML97 patients (M2 38 cases, M3 24 cases, M4 18 cases, M5 15 cases, M6 2 cases), ALL 22 cases. Control group,28 cases (11 cases of normal healthy people, non-cancer patients,17 cases). Experiment set up strict internal reference (GAPDH) and control (deionized water, or no template). Application of TaqMan probe-based real-time quantitative RT-PCR to detect patients with PRAME mRNA expression, and with FLT3 mRNA expression in comparison. Were analyzed using the relative quantitative method in acute leukemia patients PRAME, FLT3 gene are differentially expressed compared with the normal multiple, multiple target gene expression = 2-△△Ct. Where△△Ct =△CtQ-△CtC.△CtQ group of target genes for the sick and the housekeeping gene Ct value of the difference between Ct values;△CtC target genes for the control group and the housekeeping gene Ct value of the difference between the Ct value. According to the literature, when the difference between samples and negative samples expressed as a multiple of more than 10 we think that is positive.2. SPSS 10.0 statistical software used for statistical analysis, measurement data were presented as mean±standard deviation (x±s) that the two groups were analyzed using t test used to compare the rate of chi-square test, P<0.05 for the difference was significance.Results:1. PRAME expression in acute leukemiaPRAME mRNA expression in acute leukemia the relative amount of the control group 20.97-fold (t=2.42,p=0.001<0.05). One positive AML was 51.5%(50/97 patients), ALL the positive rate was 36.4%(8/22). ALL and AML groups positive rate and staining intensity compared to the difference was not statistically significant (χ2= 12.72, p=0.097>0.05)2. FLT3 expression in acute leukemiaFLT3 expression in both types of leukemia, while in normal bone marrow or peripheral blood showed no expression. FLT3 mRNA in acute leukemia the relative expression of the control group 18.64-fold (t=5.28,p=0.000<0.05). The positive rate was 80.4% among AML (78/97 patients), ALL the positive rate was 81.8% (18/22 cases). ALL, AML group and the positive rate and staining intensity compared to the difference was not statistically significant (χ2= 13.35, p=0.39>0.05)3. PRAME in normal subjects and patients with non- cancer expression11 cases of normal controls and 17 cases of non- cancer patients,5 were measured with micro-PRAME mRNA expression, its relative expression level for the part of the control group (28 patients from the whole group to remove the trace expression in 5 cases of those remaining 23 cases) of 1.37 times (t=2.06,p=0.000<0.05), and some were no significant differences (t= 0.60, p=1.47>0.05), it is still classified as a whole group, is not considered positive.4. Patients before and after treatmentShort-term tracking nine cases of PRAME, FLT3-positive patients were, in real-time quantitative RT-PCR detection of all patients after complete remission after chemotherapy, PRAME expression decreased in varying degrees (5 patients relapsed when the PRAME gene has tended to rise.9 cases of newly diagnosed patients when tracking the relative expression of the relative expression for the treatment of 15.67 times (t=2.63,p=0.007<0.05).5 cases of recurrence in patients with relapsed relative expression level after treatment was 16.22 times as. Conclusions:1. PRAME gene in normal and non- cancer of patients did not express, in acute leukemia patients with positive expression, and the expression level varies with the disease.2. PRAME gene and the FLT3 gene are associated with the detection results, as the detection of MRD, the former as the latter added.