Expression And Correlation Of SALL4 MRNA And Protein In Children's Acute Leukemia

Background:Acute leukemia (AL) is a malignant clonal hematopoietic diseases. Because of some uncertain factors, leukemia cell proliferation uncontrol, apoptosis blocked, leading to bone marrow and other hematopoietic tissue accumulation of leukemia cells proliferated, so that normal blood suppressed. The mechanism of leukemia is still unclear, researchers believe that the leukemia is more than one gene involved and affected by many factors and complex process. Multiple cancer genes, oncogenes and tumor suppressor gene dysfunction can lead to malignant cell proliferation, apoptosis by block.SALL4 is a newly discovered oncogene, which locates on chromosome 20q13.13-ql3.2, and encodes a protein with 1053 amino acid residues, with three pairs of zinc finger domain. In embryonic stem cells and embryonic development plays an important regulatory role. Earlier study found that normal hematopoietic SALL4 involved in primitive CD34 +hematopoietic cells with high expression, and expression orientation gradually reduced until in the mature blood cells are completely expressed. Subsequently found in acute myeloid leukemia and precursor B lymphoblastic leukemia/lymphoma detected abnormal expression of SALL4, suggesting SALL4 may be involved in the occurrence of hematologic malignancies. By building SALL4 animal model of transgenic mice and found that overexpression of the mouse first appeared SALL4 MDS-like dysplasia performance, that active and peripheral blood cells of bone marrow proliferation and less then 50% of the mice progressed to. Recent studies have found SALL4 gene expression abnormal increased in adult acute myeloid leukemia and acute B lymphoblastic leukemia, and in acute T lymphoblastic leukemia did not express or weakly expressed. So far, There're not expression and protein SALL4 related research reports in children with acute leukemia in China or abroad.Objective: This study was designed to test SALL4 gene and protein expression in children with acute leukemia, and obverse the relationship between the expression of SALL4 and acute leukemia of children from mRNA and protein levels, Investigate possible Mechanism of SALL4 gene in children's acute leukemia.Methods:It was observed in 50 cases of children's acute leukemia, including 30 cases of acute B lymphoblastic leukemia (B-ALL),5 cases of acute T lymphoblastic leukemia(T-ALL),15 cases of acute myeloid leukemia, and 10 cases contols in this study. We detected the expression of SALL4mRNA in bone marrow mononuclear cell by semi-quantitative (RT-PCR); and the expression of SALL4 protein in peripheral blood by ELISA. and then analyzed the correlation of SALL4 mRNA and protein.Results:1. The expression of SALL4 mRNA in AL group is significantly higher than in the control group (P<0.05);and the difference between B-ALL group and ANLL group was not significant (P>0.05); and the difference between B-ALL and T-ALL was statistically significant (P<0.05)2. The mean expression of SALL4 protein in B-ALL group, T-ALL group, ANLL and normal control group respectively were:(135.77±16.85)pg/ml (33.40±22.96) pg/ml,(151.39±64.18) pg/ml,(54.73±15.57) pg/ml.3. There was significant positive correlation between expressions of SALL4mRNA and protein (r=0.931, P<0.005).Conclusion:1. In Children's acute leukemia, the expression of SALL4mRNA and the protein in AL is high, suggesting SALL4 may be involved in the pathogenesis of acute leukemia in children.2. In Children's acute leukemia, SALL4mRNA and the protein in B-ALL and AML high expression, and positively correlated; in T-ALL and normal controls did not express. Tips SALL4 gene involved in children with acute leukemia B-ALL and ANLL incidence; not participate in the pathogenesis of T-ALL.3. In B-ALL and AML SALL4mRNA and the protein is highly expressed, and It maybe a new indicator to judge and screen the type of children's leukemia in clinic.