Hemizygous p16(INK4A) deletion in pediatric acute lymphoblastic leukemia predicts independent risk of relapse.
The genes at the INK4A/ARF locus at 9p21 are frequently involved in human cancer. Virtually all p16(INK4A) exon 2 (henceforth called p16) inactivation in pediatric acute lymphoblastic leukemia (ALL) occurs by gene deletion. The results of this study illustrate that real-time quantitative polymerase chain reaction is capable of detecting gene deletion in primary patient specimens with a precision not previously achieved by conventional methods. Importantly, this assay includes the detection of hemizygous deletions. The study revealed, strikingly, that the risk ratio for relapse for hemizygous deletion compared with no deletion was 6.558 (P =.00687) and for homozygous deletion was 11.558 (P =.000539). These results confirm and extend the authors' previous findings that homozygous deletion of p16 in pediatric ALL patients is an independent prognostic indicator of outcome from therapy.
Carter
T L
TL
Division of Children's Leukaemia and Cancer Research, TVWT Institute for Child Health Research, University of Western Australia, West Perth.
Watt
P M
PM
Kumar
R
R
Burton
P R
PR
Reaman
G H
GH
Sather
H N
HN
Baker
D L
DL
Kees
U R
UR
D000206:Actuarial Analysis; D000293:Adolescent; D001853:Bone Marrow; D002352:Carrier Proteins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D019941:Cyclin-Dependent Kinase Inhibitor p16; D018572:Disease-Free Survival; D005260:Female; D017353:Gene Deletion; D016147:Genes, Tumor Suppressor; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016133:Polymerase Chain Reaction / Q000379:methods; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000235:genetics*; D011237:Predictive Value of Tests; D011379:Prognosis; D012008:Recurrence; D016896:Treatment Outcome
D002352:Carrier Proteins; D019941:Cyclin-Dependent Kinase Inhibitor p16