PROJECT SUMMARY Biospecimen Processing and Storage Core (Core B) The proposed cancer health disparities translational research program in this P20 planning grant application relies on the submission of serial peripheral blood, bone marrow and cerebrospinal fluid (CSF) specimens from children and adolescents with acute lymphoblastic leukemia (ALL) across the participating clinical recruitment sites of the Reducing Ethnic Disparities in Acute Leukemia (REDIAL) Consortium. The Biospecimen Processing and Storage Core (BPSC) will serve as the central location where these samples will be processed into the materials needed for the specific studies in Research Projects 1 (treatment-associated hepatotoxicity) and 2 (methotrexate neurotoxicity), as well as determination of genetic ancestry for use across all projects, and biobanking of material that will be available for pilot projects through the Developmental Research Program (DRP). This Core will support the collection, shipping, processing, and storage of patient samples from each study site, as well as provide up-to-date and accurate sample annotation. The Core will follow previously developed standard operating procedures to ensure uniform collection and processing for optimal sample yield and quality. The Aims of the Core are to: 1) Receive and catalog blood, bone marrow and CSF provided by the Consortium sites; 2) Process all patient samples to isolate plasma, peripheral blood mononuclear cells, and bone marrow mononuclear cells, and separate blasts from non-blasts where appropriate; 3) Allocate and distribute samples to Projects; and 4) Maintain a biobank of samples for future research. The resulting biobank will become an extremely valuable resource for this and future translational studies examining ethnic disparities in childhood ALL.