Wan C W, McKnight M K, Brattain D E, Brattain M G, Yeoman L C
Department of Pharmacology, Baylor College of Medicine, Houston, TX 77030.
Cancer Lett. 1988 Dec 1;43(1-2):139-43. doi: 10.1016/0304-3835(88)90226-1.
The growth response to epidermal growth factor (EGF) and the numbers and types of EGF receptors were studied in three human colon tumor cell lines from each of two groups of cell lines that differ markedly in their growth properties and extent of differentiation. Aggressively growing and poorly differentiated colon cells (group I) did not respond to EGF alone, while less aggressively growing and more differentiated cells (group III) responded with increased growth when EGF was added to their chemically defined, serum-free medium. The average number of EGF receptors (EGF-R) measured at the surface of group III cell lines by radioligand binding assays, was eight-fold higher than that measured for group I cell lines. These observations provide evidence for possible autocrine mechanisms that maintain available EGF-R levels in more differentiated group III colon tumor cells and down-regulate EGF-R levels in group I colon tumor cells.
对来自两组细胞系中每组三个的人结肠肿瘤细胞系进行了研究，这两组细胞系在生长特性和分化程度上有显著差异。研究了它们对表皮生长因子（EGF）的生长反应以及EGF受体的数量和类型。生长迅速且分化程度低的结肠细胞（第一组）对单独的EGF无反应，而生长不那么迅速且分化程度更高的细胞（第三组）在将EGF添加到其化学成分明确的无血清培养基中时，生长增加。通过放射性配体结合测定法在第三组细胞系表面测得的EGF受体（EGF-R）平均数量比第一组细胞系测得的高八倍。这些观察结果为可能的自分泌机制提供了证据，该机制维持了分化程度更高的第三组结肠肿瘤细胞中可用的EGF-R水平，并下调了第一组结肠肿瘤细胞中的EGF-R水平。
