Vinores S A, Koestner A
J Neurosci Res. 1981;6(3):389-401. doi: 10.1002/jnr.490060314.
When the NGF-secreting C-6 rat glioma cells were intracerebrally injected with F98 rat anaplastic glioma cells into rats syngeneic for the F98 cells, an increased mean survival time was observed for rats developing tumors compared with those injected with only anaplastic glioma cells. Thirty percent of the rats injected with both cell types showed no signs of tumor at 90 days. Pretreatment of the anaplastic glioma cells with conditioned medium of C-6 cells did not duplicate these results unless the C-6 cells were pretreated with 17 beta-estradiol, which appears to induce secretion of an adhesion factor as well as NGF. These rats survived even longer and 33% were free of tumors at 90 days. Histological examination of tumors of the nonsurviving rats revealed that they were basically well differentiated with only small anaplastic areas remaining. Both NGF and conditioned medium from C-6 and another NGF-secreting line, S-180 mouse sarcoma, induce process formation in F98 cells and in PC12 pheochromocytoma cells, but the processes that appear following NGF exposure are morphologically different from those induced by conditioned medium. Conditioned -medium-treated cells also have a flatter appearance. In F98 cells, NGF takes longer to induce processes than does conditioned medium. The NGF-induced effects observed in both cells are neutralized by anti-NGF IgG, but those induced by conditioned media are not. Nerve growth factor (NGF) induced increased adhesiveness in F98 rat anaplastic glioma and PC12 rat pheochromocytoma cells. Conditioned media are not. Nerve growth factor induced increased adhesive-and PCuced effects observed in both cells are neutralized by anti-NGF IgG, but those induced by conditioned media are not. Nerve growth factor (NGF) induced increased adhesiveness in F98 rat anaplastic glioma and PC12 rat pheochromocytoma cells. Conditioned media are not. Nerve growth factor induced increased adhesive-and PCuced effects observed in both cells are neutralized by anti-NGF IgG, but those induced by conditioned media are not. Nerve growth factor (NGF) induced increased adhesiveness in F98 rat anaplastic glioma and PC12 rat pheochromocytoma cells. Conditioned media are not. Nerve growth factor induced increased adhesive-and PC12 cells. Anti-NGF IgG did not influence this effect on F98 cells and only partially neutralized the effect on PC12 cells, indicating that other factors may be operative in this system. Conditioned medium collected from C-6 cells pretreated with 17 beta-estradiol induced the highest degree of adhesiveness observed in both F98 and PC12 cells, and this action was unaffected by anti-NGF IgG in either case. Conditioned media from other cell lines, a variety of selected proteins, and dBcAMP did not induce increased adhesiveness. The factor responsible for this effect is nondialyzable, heat-sensitive, and ammonium-sulfate-precipitable, and its secretion appears to be stimulated by 17 beta-estradiol.
将分泌神经生长因子（NGF）的C-6大鼠胶质瘤细胞与F98大鼠间变性胶质瘤细胞一起脑内注射到对F98细胞同基因的大鼠体内时，与仅注射间变性胶质瘤细胞的大鼠相比，发生肿瘤的大鼠平均存活时间延长。注射两种细胞类型的大鼠中有30%在90天时没有肿瘤迹象。用C-6细胞的条件培养基预处理间变性胶质瘤细胞并不能重复这些结果，除非C-6细胞先用17β-雌二醇预处理，17β-雌二醇似乎能诱导一种黏附因子以及NGF的分泌。这些大鼠存活时间更长，33%在90天时没有肿瘤。对未存活大鼠的肿瘤进行组织学检查发现，它们基本上分化良好，仅残留小的间变区域。来自C-6和另一个分泌NGF的细胞系S-180小鼠肉瘤的NGF和条件培养基均可诱导F98细胞和PC12嗜铬细胞瘤细胞形成突起，但NGF处理后出现的突起在形态上与条件培养基诱导的不同。条件培养基处理的细胞外观也更扁平。在F98细胞中，NGF诱导形成突起的时间比条件培养基长。在两种细胞中观察到的NGF诱导的效应可被抗NGF IgG中和，但条件培养基诱导的效应则不能。神经生长因子（NGF）可诱导F98大鼠间变性胶质瘤细胞和PC12大鼠嗜铬细胞瘤细胞的黏附性增加。条件培养基则不能。在两种细胞中观察到的NGF诱导的黏附性增加和其他效应可被抗NGF IgG中和，但条件培养基诱导的效应则不能。神经生长因子（NGF）可诱导F98大鼠间变性胶质瘤细胞和PC12大鼠嗜铬细胞瘤细胞的黏附性增加。条件培养基则不能。在两种细胞中观察到的NGF诱导的黏附性增加和其他效应可被抗NGF IgG中和，但条件培养基诱导的效应则不能。神经生长因子（NGF）可诱导F98大鼠间变性胶质瘤细胞和PC12大鼠嗜铬细胞瘤细胞的黏附性增加。条件培养基则不能。抗NGF IgG对F98细胞的这种效应没有影响，对PC12细胞的效应仅部分中和，表明该系统中可能还有其他因素起作用。用17β-雌二醇预处理C-6细胞收集的条件培养基在F98和PC12细胞中诱导出观察到的最高程度的黏附性，并且在这两种情况下这种作用均不受抗NGF IgG的影响。来自其他细胞系的条件培养基、多种选定的蛋白质和二丁酰环磷腺苷（dBcAMP）均未诱导黏附性增加。造成这种效应的因子不可透析、对热敏感且可被硫酸铵沉淀，其分泌似乎受到17β-雌二醇的刺激。
