title: Interleukin-6 gene expression is preferentially restricted in VLA-5-MPC-1- immature but not in VLA-5+MPC-1+ mature myeloma cells.
abstract: Interleukin-6 (IL-6) is essential for the proliferation of myeloma cells, and IL-6 is considered to be produced from not only myeloma cells themselves but also microenvironments including stromal cells. To clarify which subpopulation of myeloma cells can produce IL-6, we examined IL-6 mRNA expression in immature and mature myeloma cells and normal plasma cells by RT-PCR. IL-6 mRNA expression was found in all (10/10) specimens of sorted VLA-5-MPC-1- immature myeloma cells and 27% (3/11) of VLA-5-MPC-1+ myeloma cells. On the contrary, no IL-6 mRNA was expressed in VLA-5+MPC-1+ mature myeloma cells (0/4) and CD19+CD56- normal plasma cells (0/5). IL-6R gene expression was detected in all normal and malignant plasma cells without exception. Therefore, these findings suggest that IL-6 production is preferentially restricted in immature not mature myeloma cells, and this may explain why immature myeloma cells show greater proliferative activity.
authors.affiliation: Department of Hematology and Oncology, Hiroshima University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mihara
mesh_terms: D001483:Base Sequence; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008969:Molecular Sequence Data; D009101:Multiple Myeloma / Q000235:genetics* / Q000276:immunology; D009363:Neoplasm Proteins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D017469:Receptors, Fibronectin / Q000378:metabolism*; D014407:Tumor Cells, Cultured / Q000276:immunology / Q000473:pathology
chemical_list: D015850:Interleukin-6; C084913:MPC-1 antigen; D009363:Neoplasm Proteins; D017469:Receptors, Fibronectin