ALTERATIONS OF THE PUTATIVE TUMOR-SUPPRES SOR GENE P16 MTS1 IN HUMAN HEMATOLOGICAL MALIGNANCIES/

The chromosome band 9p21-22 is frequently rearranged or deleted in a v ariety of tumors including hematological malignancies. This supports t he notion of a tumor suppressor gene in this chromosome region. Indeed , the p16/MTS1 gene encoding a cyclin-dependent kinase (CDK) inhibitor has been shown to be frequently deleted and/or inactivated by nonsens e mutations in a number of tumors. We have examined 98 DNA samples fro m blood, bone marrow cells and lymph node biopsies of patients with le ukemia (ALL and AML) or lymphoma (follicular lymphoma and T-cell lymph oma), using Southern blot hybridization and a p16/MTS1-specific probe. Molecular abnormalities, mainly homozygous deletions, were found prin cipally in ALL (8 out of 22 patients), much less frequently in AML (2/ 32) and lymphoma (2/32). While these data argue in favor of a large in volvement of p16/MTS1 in ALL, AML and lymphomas appear to be less freq uently implicated.