title: Development of a model for evaluating the interaction between human pre-B acute lymphoblastic leukemic cells and the bone marrow stromal cell microenvironment.
abstract: Clonal expansion of B-cell precursor acute lymphoblastic leukemia (ALL) is potentially regulated by survival, growth, and death signals transduced by the bone marrow (BM) microenvironment. Using a human BM stromal cell culture that supports the growth of normal human B-cell precursors, we established a pre-B ALL cell line designated BLIN-2. BLIN-2 has a clonal rearrangement of the Ig heavy chain locus, a dic(9;20) chromosomal abnormality, and a bi-allelic deletion of the p16(INK4a) and p19(ARF) genes. The most interesting feature of BLIN-2 is an absolute dependence on adherent human BM stromal cells for sustained survival and growth. BLIN-2 cultured in the absence of BM stromal cells undergo apoptosis, and direct contact with viable BM stromal cells is essential for optimal growth. BLIN-2 cells also grow on vascular cell adhesion molecule-1 (VCAM-1)-negative human skin fibroblasts, making it unlikely that a very late antigen-4 (VLA-4)/VCAM-1 interaction is required for BLIN-2 growth. Western blot analysis of BLIN-2 cells cultured in the presence or absence of BM stromal cells demonstrates that contact of BLIN-2 with BM stromal cells induces hyperphosphorylation of Rb. In contrast, the pre-B ALL cell line BLIN-1, which has a bi-allelic deletion of p16(INK4a) p19(ARF) but does not require BM stromal cells for growth, does not undergo Rb phosphorylation after BM stromal cell contact. The BLIN-2 cell line will facilitate identification of ligand/receptor interactions at the B-cell precursor/BM stromal cell interface and may provide new insight into microenvironmental regulation of leukemic cell survival and growth.
authors.affiliation: Department of Laboratory Medicine/Pathology, Center for Immunology, and the Cancer Center, University of Minnesota, Minneapolis, MN, USA.
authors.forename: N
authors.initials: N
authors.lastname: Shah
authors.forename: L
authors.initials: L
authors.lastname: Oseth
authors.forename: T W
authors.initials: TW
authors.lastname: LeBien
mesh_terms: D017209:Apoptosis; D001854:Bone Marrow Cells / Q000502:physiology*; D002450:Cell Communication; D002453:Cell Cycle; D002478:Cells, Cultured; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics; D018920:Coculture Techniques; D005260:Female; D005347:Fibroblasts / Q000502:physiology; D019942:Genes, p16; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008297:Male; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000473:pathology*; D011499:Protein Processing, Post-Translational; D016160:Retinoblastoma Protein / Q000502:physiology; D017154:Stromal Cells / Q000502:physiology; D014407:Tumor Cells, Cultured; D019010:Vascular Cell Adhesion Molecule-1 / Q000502:physiology
chemical_list: D016160:Retinoblastoma Protein; D019010:Vascular Cell Adhesion Molecule-1