The Expression Of Protection Of Telomeres1(POT1) In Patients With Acute Myeloid Leukemia(AML)

Objective1. To study the expression of protection of telomeres1(POT1) at the mRNA and protein levels;2. To explore the relationship between the expression of protection of telomeres1(POT1) and the pathogenesis of acute myeloid leukemia (AML);3. To evaluate the role of immunophenotype in diagnosis and prognosis of acute myeloid leukaemia(AML)。MethodsSelecting62patients with AML as case group and10patients with iron deficiency anemia as control group for the study, make detections as the followings:1. The expression of protection of telomeres1(POT1) gene at the mRNA levels were detected by real-time fluorescence quantitative PCR;2. The expression of protection of telomeres1(POT1) at the protein levels were detected by western blot;3. The immunophenotype of bone marrow cells in108patients with AML were detected by monoclonal antibody by flow cytometry(FCM)。4. The chromosome karyotype of patients with AML were detected by R-banding.Result According to the FAB diagnosis and classification schemes, all AML patients were divided into AML without matutation (AML-M1)(2cases), AML with matutation (AML-M2)(14cases), acute promyelocytic leukemia(AML-M3)(12cases), acute myelomonocytic leukemia(AML-M4)(14cases), acute monocytic leukemia(AML-M5)(17cases),erythroleukemia(AML-M6)(2cases),AMLwitout classification(1case);According to risk stratification standard of the experts’consensus by the Hematology Committee, all patients were divided into high risk group(24cases), medium risk group(22cases) and low risk group(16cases).1-At the mRNA levels, the expression of POT1in AML group was significantly lower than the controls (P<0.05). The expression of POT1in AML-M2group, AML-M3group, AML-M4group and AML-M5group was significantly lower than the controls (P<0.05).There was no significant difference between these groups with different classification. The expression of POT1in high risk group, medium risk group and low risk group was significantly lower than the controls (P<0.05). There was no significant difference between these groups with different risk stratification.2. At the protein levels, the expression of POT1protein in AML group was significantly lower than the controls (P<0.05). The expression of POT1in AML-M2group, AML-M4group and AML-M5group was significantly lower than the controls (P<0.05).There was no significant difference between AML-M3group and controls. There was no significant difference between these groups with different classification. The expression of POT1in high risk group, medium risk group and low risk group was significantly lower than the controls (P<0.05). There was no significant difference between these groups with different risk stratification.3. POT1protein expressed both in the cytoplasm and nucleus, There was no significant difference of the expression of POT1protein between cytoplasm and nucleus.4. We detected the immunophenotype in108patients with AML by monoclonal antibody by flow cytometry and found that AML patients expressed mainly CD33(96.3%)、CD13(88.0%)and MPO(88.0%) of Myeloid antigens, CD38(95.4%) hematopoietic stem/progenitor of antigen. There were52.8%AML patients expressed lymphoid-associated antigen.The most expressed frequently CD19(23.1%), CD7(21.3%), CD4(17.6%). Comparing with the expressions of the lymphoid-associated antigens in AML patients with different risk tratification, we found that expressions of CD4and CD7were fewer and the expression of CD19was more in low-risk group than in other groups. The difference between them were statistically significant(P<0.05);Conclusion1. The expression of POT1may be involved in related to the pathogenesis of AML.2. POT1protein expressed in both the cytoplasm and nucleus, the regulatory mechanism may be related to the telomere length;3. The detection of immunophenotype in AML patients contributes to the importance in the diagnosis classification and prognosis of AML.