The Incidence and Prognostic Significance of P16 INK4A/ P15 INK4B Gene Alterations in Children With Relapsed ALL Treated on CCG-1941

OBJECTIVES:

• Determine the incidence of p16/p15 homozygous deletions and p15 promoter hypermethylation in acute lymphocytic leukemia cells of children treated on protocol CCG-1941.
• Determine the prognostic importance of p16/p15 abnormalities in these children.
• Determine the presence or absence of p16/p15 abnormalities in the dominant clone at diagnosis if present at relapse in these patients.

OUTLINE: Frozen cells are obtained from samples collected on protocol CCG-1941. DNA is isolated and examined using Southern blot analysis to assay for deletions and promoter hypermethylation of p16 and/or p15.

PROJECTED ACCRUAL: Approximately 100 samples will be obtained for this study.