Increased cell surface EGF receptor expression during the butyrate-induced differentiation of human HCT-116 colon tumor cell clones.
Increased cell surface EGF receptor expression during the butyrate-induced differentiation of human HCT-116 colon tumor cell clones.
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在丁酸盐诱导的人 HCT-116 结肠肿瘤细胞克隆分化过程中，细胞表面 EGF 受体表达增加。
DOI：
10.1016/0014-4827(90)90146-2
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发表时间：
1990
影响因子：
3.7
通讯作者：
Morin,MJ
中科院分区：
文献类型：
--
作者：
Nathan,DF;Burkhart,SR;Morin,MJ
分离了人结肠腺癌细胞HCT-116的几个克隆亚系，并对其生长特性、固有的肠细胞样分化(碱性磷酸酶和乳糖酶活性测定)以及对结肠癌细胞成熟诱导剂丁酸盐的反应进行了鉴定。发现HCT-116亚系是异质性的，并鉴定了几个不同的表型克隆。对这些克隆的进一步鉴定表明，丁酸对细胞生长、碱性磷酸酶活性和乳糖酶活性的影响是明显的和可分离的。丁酸盐对所有克隆的生长均有抑制作用(IC50值为0.44~1.5 mM)，但对碱性磷酸酶和乳糖酶活性的影响差异很大。在一些亚系中，丁酸对两种酶中的任何一种都没有影响，而在另一些亚系中，丁酸诱导了一种或两种酶的活性。此外，125I-表皮生长因子(EGF)与细胞表面受体的结合被发现与细胞中乳糖酶活性的表达成正比。D3克隆和其他内源性乳糖酶活性大于100nmol/mg/min的亚系表达一类高亲和力的EGF受体(例如，D3细胞的EGF受体为3.48×104个/细胞，akd值为0.61nM)。其他乳糖酶活性较低的克隆有无法检测到的125I-EGF结合水平。在对丁酸反应乳糖酶活性增加两倍以上的克隆中，也诱导了大量低亲和力EGF受体的表达。在其中一个克隆株P1中，在2 mM丁酸作用96h后，乳糖酶活性从70nmol/mg/min增加到230nmol/mg/min，EGF受体的表达从检测不到的水平增加到1.18×105EGF受体/细胞(kdof3.2 nM)。Northern印迹分析表明，丁酸处理后125I-EGF结合量的增加可能部分是由于EGF受体mRNA的积累增加了一倍以上。此外，还检测了丁酸处理的细胞中转化生长因子α(α)和转化生长因子β(β)的表达情况。在Hct-116细胞克隆中，转化生长因子-EGF基因表达水平与α受体信息水平相关，而转化生长因子-β基因表达与丁酸诱导的生长抑制或这些细胞中EGF受体表达、碱性磷酸酶活性或乳糖酶活性的增加无关。
Several clonal sublines of HCT-116 human colon adenocarcinoma cells were isolated and characterized on the basis of their growth characteristics, intrinsic enterocyte-like differentiation (as assessed by alkaline phosphatase and lactase activities), and responses to butyrate, an inducer of colon tumor cell maturation. The HCT-116 sublines were found to be heterogeneous and several phenotypically distinct clones were identified. Further characterization of these clones indicated that the effects of butyrate on cell growth, alkaline phosphatase activity, and lactase activity were distinct and separable. The growth of all of the clones was inhibited by butyrate (IC50values varied from 0.44 to 1.5 mM), but the effects of this agent on alkaline phosphatase and lactase activities varied widely. In several sublines butyrate had no effect on either enzyme while in others one or both activities were induced. Additionally, the binding of125I-epidermal growth factor (EGF) to cell surface receptors was found to be proportional to the expression of lactase activity in the cell. The D3 clone and other sublines with intrinsic lactase activities greater than 100 nmol/mg/min expressed a class of high-affinity EGF receptors (e.g., D3 cells had 3.48 × 104EGF receptors/cell with akdof 0.61 nM). Other clones with less lactase activity had undetectable levels of125I-EGF binding. In clones which exhibited greater than twofold increases in lactase activity in response to butyrate, the expression of a large number of low-affinity EGF receptors was also induced. In one such clone, the P1 subline, lactase activity was increased from 70 nmol/mg/min to 230 nmol/mg/min after 96 h in 2 mMbutyrate, and the expression of EGF receptors was increased from undetectable levels to 1.18 × 105EGF receptors/cell (kdof 3.2 nM). Northern blot analysis indicated that the increased125I-EGF binding after butyrate treatment may have been due, in part, to a greater than twofold accumulation of EGF receptor mRNA. In addition, the expression of the messages for transforming growth factor alpha (TGF-α) and transforming growth factor beta (TGF-β) was examined in butyrate-treated cells. While TGF-α mRNA levels were found to correlate with EGF receptor message levels in the HCT-116 clones, TGF-β mRNA expression was not found to correlate with the butyrate-induced growth inhibition or with increases in EGF receptor expression, alkaline phosphatase activity, or lactase activity in these cells.