Detection of bcr/abl fusion transcripts by semiquantitative multiplex RT-PCR combined with a colormetric assay in Ph positive leukemia.
We studied the feasibility of the clinical application of a new bcr/abl analysis system, C-TRAK t(9;22), consisting of a multiplex RT-PCR and a colormetric assay. With this system, bcr/abl transcripts could be detected in all of 24 cytogenetic Philadelphia chromosome (Ph) positive leukemia patients and in none of eight Ph negative patients. Multiple bcr/abl transcripts could be detected in three of the 24 Ph positive patients, the fusion of bcr exon 1 to abl exon 2 (e1a2 junction) dominated that of bcr exon 13 to abl exon 2 (b2a2 junction) in two cases and that of bcr exon 14 to abl exon 2 (b3a2 junction) and b2a2 dominated e1a2 in one case. This system was sensitive enough to be able to detect even one bcr/abl transcript-producing cell in 50000 bcr/abl negative background cells, thus making it suitable for semiquantitative evaluation. Minimal residual disease (MRD) was monitored in one Ph positive leukemia patient who underwent allogenic bone marrow transplantation (allo-BMT). After allo-BMT, a weak positivity of the bcr/abl transcript continued with no clinical relapse; this result was consistent with that of a conventional nested PCR assay using ethidium bromide staining. Including all the procedures for RNA extraction, it took only about 10 h to detect the bcr/abl transcripts. Our findings indicate that this bcr/abl analysis system provides a quick and sensitive method for screening bcr/abl transcripts and possibly for monitoring MRD in Ph positive leukemia patients.
Ni
H
H
Second Department of Internal Medicine, Nagoya City University Medical School, Nagoya, Japan.
Nitta
M
M
Komatsu
H
H
Kojima
S
S
Suzuki
S
S
Harada
S
S
Tsuboi
K
K
Banno
S
S
Wakita
A
A
Yazaki
M
M
Ren
L
L
Kato
T
T
Ueda
R
R
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016026:Bone Marrow Transplantation; D002648:Child; D002675:Child, Preschool; D003124:Colorimetry / Q000379:methods; D005260:Female; D016044:Fusion Proteins, bcr-abl / Q000096:biosynthesis*; D006801:Humans; D007223:Infant; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000378:metabolism* / Q000628:therapy; D007951:Leukemia, Myeloid / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014158:Transcription, Genetic; D014178:Translocation, Genetic
D012333:RNA, Messenger; D012334:RNA, Neoplasm; D016044:Fusion Proteins, bcr-abl