Expression And Correlation Analysis Of Atg5 And Atg7 In Childhood Acute Leukemia

Objiective:Acute leukemia is a common malignant tumor in clonal disorder of hematopoietic stem cell.Now,we consider that the disorder of autophagy is closely related to tumorigenesis.Autophagy is a process of macromolecules and cellular organelle degradation by lysosomes under the chontrol of autophagy related gene in eukaryotic cells.Autophagy plays an important role in the stability of cells and is also a basic way to adapt to the intermal and external environment.We used method of immunohistochemical staining to investigate the expression level of Atg5 and Atg7 protein in bone marrow cells in childhood acute leukemia.To explore the relationship of the factors with the occurrence and development of leukemia.Methods1 Research object:50 children who were newly diagonesd with acute leukemia from January 2014 to June 2016 in the pediatric department of the Second Hospital of HeBei Medical University,were collected as experiment group.There were 30 patients with acute lymphoblastic leukemia and 20 patients with acute myelocytic leukemia.20 cases of non-malignant hematological disease children whose sex and age matched with experiment group were collected as control group,which included the immune thrombocytopenia(ITP)and nutritional anemia.2 Samples collection and disposal:2ml fresh bone marrow were collected from experiment group and control group and fixed in 4% paraformaldehyde and embedded in paraffin and sectioned for immunohistochemistry.3 Experimental method:Using immunohistochemical staining to test the expression level of Atg5 and Atg7 in defferent groups.4 The statistical analysis:The date was analyzed by SPSS 13.0-statisticalsoftware.Analysis methods included chi square test or Fisher exact propability.P value of less than 0.05 was considered as statistical significance.The relationship of Atg5 and Atg7 protien used Spearman correlation analysis to test.P value of less than 0.01 was considered as statistical significance.Results1 The expression of Atg5 protien1.1 The positive rate of Atg5 in acute leukemia(82.0%)was significantly higher than the rate in control group(40.0%).There was significant difference between them.(x2=12.0,P<0.05).1.2 The positive rate of Atg5 in acute lymphoblastic leukemia(83.3%),acute myelocytic leukemia(80.0%)and the control group(40.0%).There was significant difference between them(x2=12.063,P<0.05).1.3 The positive rate of Atg5 in acute lymphoblastic leukemia and acute myelocytic leukemia was basically the same.There was no significant difference between them(x2=0.090,P>0.0125).1.4 The positive rate of Atg5 in acute lymphoblastic leukemia compared with the rate of control group.There was significant difference(x2=10.042,P<0.0125).1.5 The positive rate of Atg5 in acute myelocytic leukemia compared with the rate of control group.There was significant difference(x2=6.667,P<0.0125).2 The expression of Atg7 protien2.1 The positive rate of Atg7 in acute leukemia(54.0%)and control group(30.0%)was basically the same.There was no significant difference between them(x2=3.302,P>0.05).2.2 The positive rate of Atg7 in acute lymphoblastic leukemia(43.3%),acute myelocytic leukemia(70.0%)and the control group(30.0%).There was significant difference between them(x2=6.7278,P<0.05).2.3 The positive rate of Atg7 in acute lymphoblastic leukemia and acute myelocytic leukemia was basically the same.There was no significant difference between them(x2=3.435,P>0.0125).2.4 The positive rate of Atg7 in acute lymphoblastic leukemia and control group was basically the same.There was no significant difference between them(x2=0.905,P>0.0125).2.5 The positive rate of Atg7 in acute myelocytic leukemia compared with the rate of control group.There was significant difference between them(x2=6.400,P<0.0125).3 There were no correlation between Atg5 and Atg7 protien in acute leukemia,by the method of Spearman correlation analysis(r=0.333,P>0.01)).Conclusions1 The expression level of Atg5 protien in the acute leukemia and acute myelocytic leukemia was increasing.Atg5 may be related to occurrence and development of acute leukemia.The expression level of Atg7 protien was only increased in acute myelocytic leukemia.Autophagy activity increased.Atg7 may be related to occurrence and development of acute myelocytic leukemia.2 Atg5 and Atg7 were expressed both in acute leukemia and non-malignant hematological disease,but the expression level was affected by the category and type of the disease.3 Although Atg5 and Atg7 all take part in the formation of autophagosome,there were no correlation between them.