Basic and clinical research on growth promoting factor for neurofibroma

Research Project

Project/Area Number	04670634
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Dermatology
Research Institution	Gunma University
Principal Investigator	ISHIKAWA Osamu Gunma University, School of Medicine Department of Dermatology Associate Professor, 医学部・皮膚科, 助教授 (90168188)
Co-Investigator(Kenkyū-buntansha)	HAYASHI Hiroaki Gunma Prefectural College Course of Radiotechnology Professor, 教授 (50008611) 堀内龍也群馬大学, 医学部附属病院・薬剤部, 教授 (90008342) 大西一徳群馬大学, 医学部・皮膚科, 講師 (60176948)
Project Period (FY)	1992 – 1994
Project Status	Completed (Fiscal Year 1994)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1994: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1992: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Neurofibromatosis / Three-dimensional culture / fibroblasts / Growth factor / mucopolysaccharides / 細胞増殖因子 / L-ascorbic Acid 2-phosphate / シグナル伝達 / rasGTP蛋白
Research Abstract	Neurofibromatosis (NF) is a most frequent hereditary disorder. Recent study disclosed NF-related gene (s) on chromosome 17 and 22. However, the precise mechanism of neurofibroma development is still unclear. We previously isolated the substance from neurofibroma and patient's sera, which specifically enhances neurofibroma-derived fibroblasts proliferation. This substance, a neurofibromaderived growth promoting factor for neurofibroma, is contained so little in neurofibroma that biochemical analysis has not been applied. To obtain a sufficient amount of neurofibroma-derived growth promoting factor, we introduced the three-dimensional culture system, in which ascorbic acid 2-phosphate was supplemented. We already confirmed this culture can provide the demis-like structure. Like the dermis, mature collagens synthesized and accumulated with glycosaminoglycans having the similar composition to the dermis. In this culture system, disaccharide analysis revealed that fibroblasts from Hunter syndrome (mucopolysaccharidosis II) produced a higher amount of dermatan sulfate than those from normal individuals. This result may suggest that in this culture system fibroblasts can maintain its phenotype as in vivo. Using this culture system, we found the fraction extracted from the three-dimensional cell layr of neurofibroma-driverd fibroblasts promoted the proliferation of neurofibroma-derived fibroblasts. In fact, only 10-30% of patients show the abnormality by the NF gene analysis. Furthermore, it is unknown how this gene product (s) is involved in the development of neurofibroma. There must be several genes responsible for neurofibromatosis. In the subsequent study, we can use this system to obtain the sufficient amount of neurofibroma-derived growth promoting factor for biochemical and molecular biological analysis.