Relationship Between The Expression Of WAVE1 And PDGFR-β In Childhood Acute Leukemia

Objective:Leukemia is the most common malignant disease of children and adolescents in our country, and revealing the pathogenesis of childhood acute leukemia is very important for its prevention and treatment. As with other malignancies, the incidence of childhood acute leukemia is involved in a number of factors, so the important aspect on the study of childhood leukemia is to determine the common disease genes, locate and separate them, and to study their biological function. WAVE1 (WASP-family verprolin homologous protein 1) is a member of the actin regulatory protein family and play an important role in regulating actin's polymerization and cytoskeleton's reorganization. Recently, over-expression of WAVE1 in human blood cancer cell lines was reported.In our previous researches, high level of WAVE1 was found in bone marrow mononuclear cells from childhood leukaemia patients, and WAVE1 was found that it was closely related to anti-apoptosis and drug resistance, but its role in leukaemia is still not clear. The study detect the expression of WAVE1 and PDGFR-βin childhood acute leukemia patients as well as in HL-60 and Raji cells, furthermore, explore the relationship between WAVE1 and PDGFR-βin leukemia and try to find whether there is a regulatory relationship.Methods:Collect bone marrow samples from acute leukemia patients, which were divided into initial treatment group, recurrence group, remission groups according to progress, and take bone marrow samples from the patients checking for anemia in the same period as control group. extract the bone marrow mononuclear cells from samples and detect the mRNA expression of WAVE 1 and PDGFR-βwith RT-PCR method; cultivate HL-60 and Raji cells,which were divided into the groups transfected with pcDNA3.1 WAVE1 (transfected group) and pcDNA3.1 empty vector (control group), as well as the groups transfected with WAVE1-siRNA (interfered group) and empty interfered vector (control group), than collect transfeced cells 48 hours later and extract RNA and protein to detect respectively the expression of WAVE1 and PDGFR-P at the mRNA and protein levels with the RT-PCR and Western Blot methods.Results:1.In acute lymphoblastic leukemia and acute nonlym-phoblastic leukemia,compared with the remission group and control group, the expression of WAVE 1 and PDGFR-βincreased significantly in the initial treatment group and the recurrence group (P<0.05); compared with recurrence group, the expression of WAVE1 and PDGFR-βhad no difference in initial treatment group and compared with control group,that was the same in the remission group (P> 0.05).2. At the mRNA level, compared to control group the expression of WAVE1 decreased in interfered group in HL-60 and Raji cells, while the expression of PDGFRβwere 182% and 141% ; transfected group's WAVE1 increased by 40% and 55% compared with control group, while PDGFRβdecreased to 54% and 65%.3. At the protein level, compared with control group the expression of WAVE1 decreased in the interfered group in HL-60 and Raji cells, while the expression of PDGFRP increased to 157% and 146%; the expression of transfected group's WAVE1 increased by 45% and 54% but PDGFRP decreased to 59%,60%.Conclusion:1. WAVE1 and PDGFR-βexpressed highly in the initial treatment group and the recurrence group, but expressed lowly in the remission group, and were related with the process of acute leukemia.2. At the levels of mRNA and protein both WAVE1 and PDGFR-β expressed in HL-60 and Raji cells, the expression of PDGFR-P was downregulated while the expression of WAVE1 increased in the transfected group, but the expression of PDGFR-βwas upregulated while the expression of WAVE 1 decreased in the interfered group.