Objective: To monitor the gene expression of BCR/ABL in chronic myeloid leukemia patients after allogeneic hematopoietic stem cells transplantation with real-time RT-PCR for evaluating therapeutic efficacy and guiding further treatment.
Methods: Taqman real-time RT-PCR technique was performed to monitor peripheral blood BCR/ABL transcript levels in 10 patients at the time of diagnosis and serially at intervals in 25 patients after allogeneic hematopoietic stem cells transplantation. beta-actin mRNA was used as an endogenous reference.
Results: The sensitivity of real-time RT-PCR was 10 copies/microl. In 15 patients receiving transplantation, the median of N(BCR/ABL) (%) before transplantation, 1 month after transplantation and 2 months after transplantation was respectively: 6.57 (0.14 - 38.83), 0.10 (0 - 1.71) and 0 (0 - 0.52). 3 months later N(BCR/ABL) (%) all turned to 0. BCR/ABL transcripts after transplantation were detected to decrease gradually. N(BCR/ABL) (%) 1 month after transplantation and 2 months after transplantation was both lower than that before transplantation (chi(2) both = 13.07, P < 0.01). N(BCR/ABL) (%) at 2 months after transplantation was lower than that at 1 month after transplantation (chi(2) = 8.10, P < 0.01). In 10 other patients, N(BCR/ABL) (%) was 0 in consecutive tests from 3 to 43 months after transplantation.
Conclusion: Real-time RT-PCR is sensitive, reliable and reproducible for monitoring CML relapse after transplantation. It is of help in detecting minimal residual disease, predicting the prognosis of the disease and providing practical indications for further treatment.