Contact-dependent growth inhibition and apoptosis of epidermal growth factor (EGF) receptor-expressing cells by the membrane-anchored form of heparin-binding EGF-like growth factor
Contact-dependent growth inhibition and apoptosis of epidermal growth factor (EGF) receptor-expressing cells by the membrane-anchored form of heparin-binding EGF-like growth factor
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DOI：
10.1074/jbc.274.36.25906
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发表时间：
1999-09-03
影响因子：
4.8
通讯作者：
Mekada, E
中科院分区：
文献类型：
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作者：
Iwamoto, R;Handa, K;Mekada, E
肝素结合表皮生长因子样生长因子 (HB-EGF) 通过 EGF 受体 (EGFR) 转导有丝分裂信号。 HB-EGF 有两种形式，膜锚定形式 (pro-HB-EGF) 和可溶形式 (sHB-EGF)。我们通过使用表达 pro-HB-EGF 的效应细胞与表达 EGFR 的靶细胞共培养的模型研究了 pro-HB-EGF 的生物活性。 DER细胞是白细胞介素3依赖性造血32D细胞系的表达EGFR的衍生物，在存在EGF或sHB-EGF而无IL-3的情况下生长良好。当DER细胞在过表达pro-HB-EGF的单层Vero-H细胞上共培养时，即使在存在过量EGF或sHB-EGF的情况下，在DER细胞中也会诱导生长抑制和随后的凋亡。当培养基中添加 pro-HB-EGF 的特异性拮抗剂或阻止 DER 细胞与 Vero-H 细胞直接接触时，DER 细胞被消除，表明 pro-HB-EGF 参与了这种抑制作用。即使在 IL-3 存在的情况下，也观察到 Pro-HB-EGF 诱导的 DER 细胞凋亡。这排除了可溶性 EGFR 配体和 pro-HB-EGF 之间简单竞争的可能性。此外，表达由EGFR的胞外和跨膜结构域以及促红细胞生成素受体的细胞质结构域组成的EGFR突变体的32D细胞通过与Vero-H细胞共培养没有经历细胞凋亡，这表明表达pro-HB-EGF的Vero-H细胞诱导的抑制信号通过EGFR介导到DER细胞，并且EGFR的细胞质结构域对于pro-HB-EGF诱导的细胞凋亡是必需的。根据结果，我们得出结论，pro-HB-EGF 通过细胞与细胞接触而具有独特的生物活性，这与 sHB-EGF 的活性不同。
Heparin-binding epidermal growth factor-like growth factor (HB-EGF) transduces mitogenic signals through the EGF receptor (EGFR). There are two forms of HB-EGF, the membrane-anchored form (pro-HB-EGF) and the soluble form (sHB-EGF), We studied the biological activity of pro-HB-EGF by using a model in which pro-HB-EGF-expressing effector cells was co-cultured with EGFR-expressing target cells. The DER cell, an EGFR-expressing derivative of the interleukin-3-dependent hematopoietic 32D cell line, grows well in the presence of EGF or sHB-EGF without IL-3, When DER cells were co-cultured on a monolayer of Vero-H cells overexpressing pro-HB-EGF, growth inhibition and subsequent apoptosis were induced in the DER cells even in the presence of excess amounts of EGF or sHB-EGF, Such growth inhibition of DER cells was abrogated when specific antagonists for pro-HB-EGF were added in the culture medium or when direct contact of DER cells with Vero-H cells was prevented, indicating that pro-HB-EGF is involved in this inhibitory effect. Pro-HB-EGF-induced apoptosis of DER cells was also observed even in the presence of IL-3. This rules out the possibility of simple competition between soluble EGFR ligands and pro-HB-EGF. Moreover, 32D cells expressing EGFR mutant composed of the extracellular and the transmembrane domain of EGFR and the cytoplasmic domain of erythropoietin receptor did not undergo apoptosis by co-culture with Vero-H cells, indicating that the inhibitory signal induced by pro-HB-EGF-expressing Vero-H cells is mediated to DER cells via EGFR and that the cytoplasmic domain of EGFR is essential for pro-HB-EGF-induced apoptosis, From these results, we concluded that pro-HB-EGF has unique biological activity through cell-cell contact that is distinct from the activity of sHB-EGF.