Preliminary Study Of Gene Expression Profile Of Children Patients With Acute Lymphoblastic Leukemia

Objective:The gene expression profiles of ALL children patients were researched by the gene chip technology preliminarily in order to identify the new genes associated with the early diagnosis,treatment and prognosis of ALL.The differently expressed genes were validated by the real-time quantitative RT-PCR.The discovery of new genes can lead to obtain the relationship between genes and diseases and guide significance for the clinical treatment efficacy.Methods:1.Group A and group B were both composed of three new children patients of ALL who were preliminarily diagnosed of standard risk group in accordance with the CCLG-2008 program.After re-evaluation Group A and group B were relegated to standard risk group and high-risk group respectively.The experimental group was composed of group A and group B,while the control group was composed of three idiopathic thrombocytopenic purpura patients.The total RNA extracted from bone marrow mononuclear cells was used to synthesize the cDNA and reverse transcription cRNA.The cRNA was hybridized to Illumina Human-6 Beadchip.After washing,gene microarray was scanned for the fluorescent signal by Illumina BeadSation in order to compare the differences of gene expression profiles between group A and group B.2.The experimental group was composed of 82 children patients of ALL,while the control group was composed of 15 normal subjects.Expression levels of the three genes were measured between the experimental group and the control group by quantitative real-time RT-PCR in order to research the significance of three genes differentially expressed among different groups and the relationship between the three genes and clinical factors.Result: 1.â‘ There were 19 genes differently expressed between group B and group A.14 genes were found up-regulated including ABCC4 and BCL11A and 5 genes were found down-regulated including TOP2A.â‘¡The three genes ABCC4,BCL11A and TOP2A were further studied.ABCC4 and TOP2A were two multidrug resistance genes.BCL11A was a gene whose function was closely related to the mechanism of malignant disease.â‘¢These differently expressed genes were clustered by their functions.The results showed that they were associated with cell apoptosis,cell adhesion,cell signaling,cell differentiation,cytoskeletal structure,metabolism and other related processes.2.â‘ ABCC4 and BCL11A,two up-regulated genes,were validated by the real-time quantitative RT-PCR that the gene expression level of the high risk group was superior to the high risk group.The differences between the two groups had significance in statistics (p <0.05).The gene expression level of the experimental group of leukemia was superior to the normal control group and the differences between them had significance in statistics(p <0.01).The results also showed that the different gene expression levels of the other groups had no significance in statistics.â‘¡TOP2A,a down-regulated gene,was validated by the real-time quantitative RT-PCR that the gene expression level of the high risk group was lower than the standard risk group. The differences between the two groups had significance in statistics(p <0.05).The gene expression level of the experimental group of leukemia was lower than the normal control group and the differences between them had significance in statistics(p <0.01).The results also showed that the different expression level of the other groups had no significance in statistics.â‘¢There were no significant differences between the expression level of BCL11A mRNA and the differences of clinical indicators(p value> 0.05).There were significant differences between the expression level of ABCC4 mRNA and the differences between the remission of clinical indicators(p value <0.05).There were significant differences between the expression level of TOP2A mRNA and the differences between remission and prednisone trial of clinical indicators respectively(p value <0.05).Conclusion:1.These genes were found differently expressed in children patients of ALL by gene chip technology and involved in apoptosis,cell signaling,cell differentiation,the formation of cytoskeletal structure,metabolic processes and so on.2.Three genes,ABCC4,BCL11A and TOP2A were all analyzed by quantitative RT-PCR. The ABCC4 gene,a up-regulated multidrug resistance gene,can be used to assess the clinical efficacy of children patients of ALL.The BCL11A gene,a up-regulated,was closely related to the pathogenesis of children patients of ALL.The TOP2A gene,a down-regulated gene,can be used to therapy targets of children patients of ALL.3.The gene chip technology and quantitative RT-PCR had important clinical value in precise diagnosis,prognosis,early intervention and target therapy of children patients of ALL.