Helseth E, Unsgaard G, Dalen A, Vik R
Brain Tumour Research Laboratory, University Hospital of Trondheim, Norway.
Acta Neurochir Suppl (Wien). 1988;43:118-20. doi: 10.1007/978-3-7091-8978-8_25.
Type beta transforming growth factor (B-TGF) is a potent regulator of cell growth and differentiation. Growth of many human tumour cell lines are inhibited by B-TGF. The effect of B-TGF on proliferation of clonogenic cells from 12 human glioma biopsies was registrated in a thymidine incorporation assay. B-TGF appeared to be a potent growth inhibitor for some gliomas, while it had no effect on others. Maximum inhibition was about 60%. Though not significant, glioblastomas appeared to be less sensitive to inhibition by B-TGF than astrocytomas and oligodendrogliomas. Very little is known about the growth inhibitory action of B-TGF. The negative autocrine growth theory for cancer cells postulates that a reduced production, or production of a defective growth inhibitor normally found in the cell, may account for the autonomous nature of some cancer cells. In view of this theory, we searched for B-TGF in protein extracts from a glioblastoma cell line, T-MGl, whose growth was inhibited by B-TGF. Protein extract from T-MGl cells was analysed for B-TGF activity using a soft agar colony formation assay with normal rat kidney fibroblasts. B-TGF was not found in the extract. Since, according to the literature B-TGF has been found in all other cell lines examined, we believe that there may be a lack of B-TGF or an altered B-TGF in the gliomas whose growth are inhibited by B-TGF. This problem will be studied further.
β型转化生长因子（B-TGF）是细胞生长和分化的有效调节因子。许多人类肿瘤细胞系的生长受到B-TGF的抑制。在一项胸苷掺入试验中记录了B-TGF对12例人类胶质瘤活检组织中克隆形成细胞增殖的影响。B-TGF似乎是某些胶质瘤的有效生长抑制剂，而对其他胶质瘤则没有影响。最大抑制率约为60%。虽然不显著，但胶质母细胞瘤似乎比星形细胞瘤和少突胶质细胞瘤对B-TGF抑制的敏感性更低。关于B-TGF的生长抑制作用知之甚少。癌细胞的负自分泌生长理论假定，细胞中通常发现的生长抑制剂产量降低或产生缺陷，可能解释了某些癌细胞的自主性。鉴于这一理论，我们在一种胶质母细胞瘤细胞系T-MGl的蛋白质提取物中寻找B-TGF，该细胞系的生长受到B-TGF的抑制。使用正常大鼠肾成纤维细胞的软琼脂集落形成试验分析T-MGl细胞的蛋白质提取物中的B-TGF活性。提取物中未发现B-TGF。由于根据文献，在所有其他检测的细胞系中都发现了B-TGF，我们认为在生长受到B-TGF抑制的胶质瘤中可能存在B-TGF缺乏或B-TGF改变的情况。这个问题将进一步研究。
