Fundamental study of neuronal cell differentiation system by transfection with glial fibrillary acidic protein gene.

胶质纤维酸性蛋白(GFAP)是在成熟的正常星形胶质细胞和分化的胶质瘤细胞中发现的一种中间丝，它似乎与微丝、微管等其他细胞骨架成分一起稳定星形胶质细胞的细胞骨架，帮助维持星形胶质细胞的形态，但其组织特异性作用尚不清楚。通过脂质体将GFAP基因导入不表达GFAP的人髓母细胞瘤细胞系(DAOY-1)，以验证GAFP在脑瘤细胞中的表达效果。转染后，我们研究了GFAP转染组细胞的生物学特性变化。比较GFAP转染组与未转染组的细胞生长、细胞形态及对细胞因子或抗癌药物的敏感性。结果表明，GFAP基因转染的细胞1)生长抑制，2)对某些抗癌药物如ACNU和顺铂的敏感性增加，3)高表达肿瘤相关细胞表面抗原，如已知的细胞间黏附分子之一G-22，4)形态变化不明显。这些结果提示GFAP基因转导细胞对抗癌药物具有更高的敏感性，有望在脑肿瘤的治疗中得到临床应用。

Glial fibrillary acidic protein (GFAP) is one of the intermediate filaments which was found in mature normal astrocytes and differentiated glioma cells It seems to stabilize the astrocyte's cytoskeleton and help maintain astrocyte cell shape together with other cytoskeletal components such as microfilament and microtubule, however its tissue-specific role is not clear. To verify the effect of GAFP expression in brain tumor cell, transfer of GFAP gene into human medulloblastoma cell line (DAOY-1) which dose not express GFAP was performed by means of liposomes. After tranfection, we studied the alteration of chracteristics in GFAP transfected cells. Cell growth, morphology and sensitivity of cytokine or anticancer drugs were compared between GFAP transfected and non-transfected cells. As a result, the GFAP gene transfected cells demonstrated that, 1) Growth inhibition, 2) Increase of sensitivity to some anticancer drugs such as ACNU and Cisplatinum, 3) High expression of tumor related cell surface antigen such as G-22, which is known as one of the intercellular adhesion molecule, 4) although morphological changes was not apparent. These results suggest that GFAP gene transfected cell has a possibility to be more sensitive for the anticancer drugs, and it is expected the clinical application for the treatment of malignant brain tumors.