Growth factors derived from a human malignant glioma cell line, U-251MG

• Published in: Journal of neuro-oncology Vol. 7; no. 3; p. 225
• Main Authors: Kuratsu, J, Estes, J E, Yokota, S, Mahaley, Jr, M S, Gillespie, G Y
• Format: Journal Article
• Language: English
• Published: United States 01.09.1989
• Subjects: Animals; Blotting, Northern; Chromatography, Gel; Cross Reactions; Culture Media; Cycloheximide - pharmacology; DNA - biosynthesis; Glioma - analysis; Glioma - metabolism; Growth Substances - analysis; Growth Substances - biosynthesis; Growth Substances - physiology; Humans; Kinetics; Lipopolysaccharides - pharmacology; Mice; Nucleic Acid Hybridization; RNA - genetics; RNA - isolation & purification; Tumor Cells, Cultured - analysis; Tumor Cells, Cultured - drug effects; Tumor Cells, Cultured - metabolism
• ISSN: 0167-594X
• DOI: 10.1007/BF00172915

A human malignant glioma cell line, U-251 Mg, cultured under serum free conditions, was shown to produce a growth factor for BALB/c 3T3 cells (glioma-derived growth factor-1, GDGF-1). The biological activity of GDGF-1 resided in a heat- and acid-resistant protein with a molecular weight (MW) of 25 kDa estimated by gel permeation chromatography. GDGF-1 activity was neutralized by a goat anti-human platelet derived growth factor (PDGF) antibody, indicating that the two factors were immunologically related. Furthermore, U-251 Mg cells constitutively expressed c-sis mRNA. When U-251 Mg cells were stimulated with bacterial lipopolysaccharide, 2 novel growth factors (GDGF-2 and GDGF-3) were produced in addition to the PDGF-like substance. GDGF-2 was determined to be greater than 100 kDa MW and was not neutralized by the goat anti-PDGF antiserum. The biological activity of GDGF-3 was also heat- and acid-resistant with an apparent 14 kDa MW. This factor also did not show any common antigenicity with PDGF. GDGF-2 and GDGF-3 are currently under investigation and evidence as to their natures will be published elsewhere. Our findings with this glioma cell line provide further evidence that inappropriate expression of growth factor-related genes could play important autocrine role(s) in the processes leading to malignant transformation and/or uncontrolled proliferation and may provide a paracrine stimulus for such processes as glioma neovascularization.