Detection of minimal residual disease in patients with AML1/ETO-associated acute myeloid leukemia using a novel quantitative reverse transcription polymerase chain reaction assay.
The AML1/ETO fusion transcript can be detected by reverse transcription polymerase chain reaction (RT-PCR) in patients with t(8;21)-associated acute myeloid leukemia (AML) in long-term complete remission (CR). Quantitation of the amount of the fusion transcript during CR may therefore be more predictive of cure or relapse than a simple qualitative assessment. Real Time PCR, a fluorometric-based technique, allows simple and rapid quantitation of a target sequence during the extension phase of PCR amplification, in contrast to end-point quantitative methods. Six patients with t(8;21)(q22;q22) AML, who achieved CR were studied by Real Time RT-PCR at different time intervals following diagnosis and high-dose cytarabine and anthracycline-based induction therapy. Five patients had a diagnostic bone marrow (BM) sample available for molecular analysis. Each patient showed > or = 10(3) copies of the AML1/ETO fusion transcript at diagnosis, and each showed a 2- to 4-log decrease in copy number following successful induction chemotherapy. This is comparable to the log-fold reduction in leukemic blasts that is thought to occur in patients successfully cytoreduced into CR by induction chemotherapy. The sixth patient showed a relatively high copy number immediately following successful remission induction chemotherapy, which continued to increase during early CR and was later followed by relapse. Real Time RT-PCR appears to offer advantages over previously used quantitative RT-PCR methods by providing absolute quantitation of the target sequence, expanding the dynamic range of quantitation to over six orders of magnitude, eliminating the post-PCR processing, and reducing labor and carryover contamination. These features make this an attractive method to prospectively evaluate the prognostic value of AML1/ETO fusion transcript quantitation in a larger patient population with t(8;21)(q22;q22) AML in CR.
Marcucci
G
G
Department of Internal Medicine, Comprehensive Cancer Center at The Ohio State University, Columbus 43210, USA.
Livak
K J
KJ
Bi
W
W
Strout
M P
MP
Bloomfield
C D
CD
Caligiuri
M A
MA
D000208:Acute Disease; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics; D050676:Core Binding Factor Alpha 2 Subunit; D005240:Feasibility Studies; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics; D018365:Neoplasm, Residual; D015514:Oncogene Proteins, Fusion; D016133:Polymerase Chain Reaction / Q000379:methods*; D000075142:RUNX1 Translocation Partner 1 Protein; D011993:Recombinant Fusion Proteins / Q000032:analysis; D012074:Remission Induction; D014157:Transcription Factors / Q000032:analysis*; D014178:Translocation, Genetic / Q000235:genetics
C107844:AML1-ETO fusion protein, human; D050676:Core Binding Factor Alpha 2 Subunit; D015514:Oncogene Proteins, Fusion; D000075142:RUNX1 Translocation Partner 1 Protein; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors