Terzaghi-Howe M, McKeown C
Cancer Res. 1986 Feb;46(2):917-21.
There is mounting evidence that normal cells can either inhibit the growth of carcinogen-altered cells and/or affect progression to a neoplastic phenotype. This effect(s) has been observed both in vivo in intact rat tracheal tissues and in rat tracheal epithelial cell cultures. The inhibition of carcinogen-altered cells in culture appears to be associated with the production of an acid and heat stable, dithiothreitol sensitive, nondialyzable protein produced by normal tracheal epithelial cells or esophageal epithelial cells in primary culture. It was found to be optimally produced by 3-4-week-old cultures of normal epithelial cells. In the presence of a 1:4 dilution of normal cell conditioned medium, the colony forming efficiency of a sensitive cell line is decreased 5-fold. Biochemical properties of the inhibitor are similar to those associated with type beta transforming growth factor.
越来越多的证据表明，正常细胞既可以抑制致癌物改变细胞的生长，和/或影响向肿瘤表型的进展。这种效应在完整大鼠气管组织的体内实验以及大鼠气管上皮细胞培养中均有观察到。培养中对致癌物改变细胞的抑制似乎与原代培养的正常气管上皮细胞或食管上皮细胞产生的一种对酸和热稳定、对二硫苏糖醇敏感、不可透析的蛋白质有关。发现它在3 - 4周龄的正常上皮细胞培养物中产生最为理想。在正常细胞条件培养基1:4稀释液存在的情况下，敏感细胞系的集落形成效率降低5倍。该抑制剂的生化特性与β型转化生长因子相关的特性相似。
