MiR-155 And SHIP1 Expression In MRNA Level Between Acute Myeloid Leukemia Patients With Or Without FLT3-ITD Mutation

Objective:This study aimed to elucidate the expression level difference of miRNA155 and SHIP1 mRNA in patients with and without FLT3-ITD mutation in normal karyotype AML patients,and analyze their possible significance or even a relationship between the expression change of miRNA155 and SHIP1 which may finally cast a light on the mechanism of the development of AML with FLT3-ITD mutation.Methods:(1)Bone marrow samples were harvested from 60 cases of normal karyotype patients who were diagnosed as AML by MICM typing in our hospital from May 2013 to February 2018 including 30 cases with FLT3-ITD mutation and 30 cases without the mutation,and collected clinical datas by theway.In addition,18 cases of healthy volunteers or patients with nutritional anemia were collected as control.(2)The mRNA expression of SHIP1,miR-155 in bone marrow mononuclear cells was detected by real time fluorescence quantitative PCR.The formula 2~-?Ct?Ct was used to calculate relative gene expression level.(3)The experimental data are distributed in a non normal state,and the results are described by M(P25,P75).Statistical analysis was done by adopting the statistical software SPSS 21.Kruskal-Walllis H test was used in comparison among multiple groups,and Mann-Whitney U test was used in comparison between the two groups.Spearman correlation test was used for correlation analysis.P?0.05 was considered statistically significant.Results:(1)The average peripheral blood leucocyte count in patients without FLT3-ITD mutation was 55.8536×10~9/L,and the patients with the mutation was 118.2737×10~9/L,the difference was statistically significant(P=0.012).(2)The median expression level of SHIP1 mRNA in the AML patients with FLT3-ITD mutation was 0.030186(0.007359,0.102351),and in the patients without FLT3-ITD mutation was 0.094895(0.055821,0.198383),both were significantly lower than that in the control group 0.180297(0.128451,0.223372),the difference was statistically significant(P<0.05);Compared with the mutation negative group,the expression level of SHIP1mRNA was significantly lower in mutation positive group,the difference was statistically significant(P=0.007).(3)The median expression level of miR-155 in the AML patients with FLT3-ITD mutation was 8.708970(5.392652,13.337038),and in the patients without FLT3-ITD mutation was 6.030487(1.159054,10.205599),both were significantly higher than that in the control group 0.226674(0.133817,0.292243),the difference was statistically significant(P<0.05);Compared with the mutation negative group,the expression level of miR-155was significantly higher in mutation positive group,the difference was statistically significant(P=0.011).(4)In AML patients,the correlation analysis results showed:a correlation coefficient of r=0.379 was found between the expression of miR-155 and SHIP1 mRNA in the FLT3-ITD mutation negative group(P=0.039);and a correlation coefficient of r=0.093 was found between the expression of miR-155 and SHIP1 mRNA in the FLT3-ITD mutation positive group(P=0.623).Conclusion:1.The average peripheral blood leucocyte count level in patients with FLT3-ITD mutation is higher than that in the negative group.2.The expression of SHIP1 mRNA was lower in the AML patients with FLT3-ITD mutation compared with in the control group and the patients without FLT3-ITD mutation,3.The expression of miR-155 was higher in the AML patients with FLT3-ITD mutation compared with in the control group and the patients without FLT3-ITD mutation,4.In the AML patients with and without FLT3-ITD mutation,there was no significant correlation between the expression of SHIP1 mRNA and miR-155.