OBJECTIVETo establish the real time quantitative PCR (RQ-PCR) assay according to 'Europe Against Cancer' (EAC) program and analyze the results of detection and quantification of different PML-RAR alpha transcript isoforms in patients with acute promyelocytic leukemia (APL).

METHODSThree RQ-PCR systems were performed to detect the most frequent PML-RAR alpha transcripts (L-form, S-form and V-form) in 30 APL patients and the RQ-PCR end-point products were identified by electrophoresis.

RESULTSS-form RQ-PCR system could amplify positive signals of three isoforms in all of 30 cases, and V-form RQ-PCR system could do so in both L-form and V-form positive cases, however, L-form RQ-PCR system could only do so in L-form-positive cases. Electrophoresis and sequencing of end-point products amplified by S-form RQ-PCR system revealed three bands in each of L-form (621 bp, 477 bp and 218 bp) and V-form (567 bp, 423 bp and 218 bp) positive patients samples.

CONCLUSIONSRQ-PCR, sensitive and reliable, can be used for monitoring the minimal residual disease in APL patients, however, its results should be interpreted carefully if it is used for detection of PML-RAR alpha fusion transcripts prospectively.