Molecular analysis of the PML/RAR alpha chimeric gene in pediatric acute promyelocytic leukemia.
Acute promyelocytic leukemia (APL) is characterized cytogenetically by the t(15;17)(q22;q11-21) translocation. To compare molecular events among pediatric and adult APL cases, we designed two sets of oligonucleotide primers using published cDNA sequence for PML/RAR alpha fusion transcripts, and undertook reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of 22 US pediatric cases of APL. PML/RAR alpha fusion transcripts were detected in all APL cases, including two cases lacking cytogenetic evidence of t(15;17). Breakpoint usage in PML was determined using a combination of PCR amplification with differing 5' primers, junction-specific probes, and sequence analysis in selected cases. Consistent with previously published data, case analysis demonstrated fusion products resulting from three breakpoint cluster regions (bcr) in PML, and a single breakpoint region in intron 2 of RAR alpha. Transcripts resulting from breakpoints in bcr1 were detected in 59 percent of cases, bcr2 in 27 percent and bcr3 in 14 percent. This distribution is dissimilar to that observed in adults, where bcr2 comprises a lesser and bcr3 a greater portion of cases. These results suggest that the pathogenesis of the t(15;17) in APL may differ among patient sets. RT-PCR with these primer sets is a reliable method for detecting PML/RAR alpha chimeric transcript in t(15; 17)-containing APL.
Kane
J R
JR
Department of Hematology-Oncology, St Jude Children's Research Hospital (SJCRH), Memphis, TN.
Head
D R
DR
Balazs
L
L
Hulshof
M G
MG
Motroni
T A
TA
Raimondi
S C
SC
Carroll
A J
AJ
Behm
F G
FG
Krance
R A
RA
Shurtleff
S A
SA
Downing
J R
JR
D000328:Adult; D000595:Amino Acid Sequence; D001483:Base Sequence; D002648:Child; D002678:Chimera; D002874:Chromosome Mapping; D002884:Chromosomes, Human, Pair 15; D002886:Chromosomes, Human, Pair 17; D017931:DNA Primers; D005091:Exons; D016313:Genes, abl; D006801:Humans; D007438:Introns; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics*; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D015345:Oligonucleotide Probes; D015513:Oncogene Proteins / Q000235:genetics; D016133:Polymerase Chain Reaction; D000071156:Promyelocytic Leukemia Protein; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins; D051562:Proto-Oncogene Proteins c-bcr; D018168:Receptors, Retinoic Acid / Q000096:biosynthesis / Q000235:genetics*; D000072482:Retinoic Acid Receptor alpha; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D014158:Transcription, Genetic; D014178:Translocation, Genetic; D025521:Tumor Suppressor Proteins
D017931:DNA Primers; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D015345:Oligonucleotide Probes; D015513:Oncogene Proteins; D000071156:Promyelocytic Leukemia Protein; D011518:Proto-Oncogene Proteins; C000607071:RARA protein, human; D018168:Receptors, Retinoic Acid; D000072482:Retinoic Acid Receptor alpha; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human; D011505:Protein-Tyrosine Kinases; C496613:BCR protein, human; D051562:Proto-Oncogene Proteins c-bcr