The Expression of Human Telomerase Reverse Transcriptase in Adult Acute Myeloid Leukemia and Its Correlation With Various Clinico-Pathological Parameters

BACKGROUND: Acute myeloid leukemia (AML) is a heterogeneous disorder characterized by clonal expansion of myeloid progenitors (blasts) in the bone marrow and peripheral blood, AML accounts for 80% of acute leukemia in adults, its incidence increase with age. AML can be a fatal disease so research to predict prognosis is important. Telomerase (TA) is an enzyme that stabilizes the telomere length and makes the cell immortal. It is present in some of the normal cells, fetal cells, adult germ cells, and presents in 85% of tumors in humans, it has been shown that TA can be used as a prognostic marker in some solid and hematological neoplasms. Telomere length is a factor that predicts telomere function. AIM: We test the quantitative amount of human telomerase reverse transcriptase (hTERT) gene expression in AML (diagnosed according to FAB) adult and its correlation with various clinic-pathological parameters. PATIENTS & METHODS: We used the TRAP assay to assess the hTERT gene expression in mononuclear blood cells from 40 newly diagnosed AML patients, 25 AML patients after completing their course of treatment, and 15 control health subjects. RESULTS: The mean value of hTERT in AML and control groups were [1.59 ± 1.27 anm and 0.035 ± 0.046 anm respectively], and this difference was significantly higher in patients than in control group (p = 0.0001). The telomerase activity was positive in 27 (67.5%) AML patients, while 13 (32.5%) AML patients were negative for telomerase activity. Twenty-five patients after induction chemotherapy were followed up by bone marrow and peripheral blood examination to determine the patient’s response to therapy. Complete hematological remission was achieved in 12 (48.0%) patients and incomplete hematological remission in 13 (52.0%) patients (14%). The hTERT level was significantly higher in patients before induction chemotherapy than after completion of the induction course (p = 0.0001). The hTERT level at diagnosis in patients who did not achieve complete hematological remission was significantly higher than that in patients who achieved complete hematological remission (p = = 0.026). The hTERT level after induction therapy was significantly higher in patients who did not achieve complete hematological remission than in patients who achieved complete hematological remission (p = 0.003). CONCLUSION: Our research suggests that the hTERT expression could serve as a prognostic marker for AML patients.