Real-time quantitative detection of E2A-PBX1 fusion gene in children with acute lymphoblastic leukemia and its clinical application in minimal residual disease monitoring
OBJECTIVE: To establish a real-time reverse transcription-polymerase chain reaction (RT-PCR) for quantitative detection of E2A-PBX1 fusion gene mRNA in acute lymphoblastic leukemia (ALL) children and to explore its clinical significance in minimal residual disease monitoring and prognosis evaluation. Methods: Real-time RT-PCR was used to quantitatively detect the mRNA expression of E2A-PBX1 gene in 11 newly diagnosed ALL patients at diagnosis (11 cases), complete remission (11 cases) and periods of relapse (3 cases). Ten children with normal bone marrow cell morphology and without hematopathy or tumor diseases were used as the control group. RESULTS: The median expression levels of E2A-PBX1 fusion gene in the ALL group at diagnosis and the relapse group were significantly higher than in the control and complete remission groups (P<0.01). Compared with E2A-PBX1 negative patients on day 33 during induction of remission, the recurrence rate increased and disease free survival rate at 3 year decreased significantly in E2A-PBX1 positive patients decreased (P<0.05). CONCLUSIONS: Measurement of E2A-PBX1 levels by real-time RT-PCR is useful for monitoing minimal residual disease, prediction of relapse and individual treatment. The expression level of E2A-PBX1 gene on day 33 during induction of remission can be used for prognosis evaluation.