Acetylcholine-induced activation of M3 muscarinic receptors stimulates robust matrix metalloproteinase gene expression in human colon cancer cells
Acetylcholine-induced activation of M3 muscarinic receptors stimulates robust matrix metalloproteinase gene expression in human colon cancer cells
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DOI：
10.1152/ajpgi.90519.2008
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发表时间：
2009-04-01
影响因子：
4.5
通讯作者：
Raufman, Jean-Pierre
中科院分区：
文献类型：
--
作者：
Xie, Guofeng;Cheng, Kunrong;Raufman, Jean-Pierre
先前，我们发现乙酰胆碱诱导的人结肠癌细胞增殖是通过表皮生长因子（EGF）受体（egfr）的反激活介导的。在本研究中，我们阐明了这一作用的分子机制。ach诱导的仅表达M3毒蕈碱受体（M(3)Rs）的H508结肠癌细胞的增殖被抗EGFR配体结合域抗体、广谱基质金属蛋白酶（MMP）抑制剂、抗mmp7抗体、阻断EGFR配体释放的白喉毒素类似物[肝素结合egf样生长因子（HBEGF）]和抗HBEGF抗体所减弱。ach处理的H508细胞的条件培养基诱导了表达EGFR而不表达M3R的SNU-C4结肠癌细胞的增殖。这些作用被EGFR抑制剂和抗EGFR和抗hbegf抗体减弱。在H508，而不是SNU-C4，结肠癌细胞中，乙酰胆碱引起MMP7 mRNA和MMP7蛋白水平显著的剂量和时间依赖性增加。同样，乙酰胆碱诱导了MMP1和MMP10基因的转录。乙酰胆碱诱导的MMP1、MMP7和MMP10基因转录被阿托品、抗EGFR抗体和EGFR和ERK激活的化学抑制剂减弱。相比之下，磷脂酰肌醇3-激酶抑制剂和nf - κ B激活抑制剂没有改变MMP基因的转录。总之，这些发现表明，mmp7催化的HBEGF释放介导乙酰胆碱诱导的EGFR反激活和随之而来的结肠癌细胞增殖。ach诱导的EGFR和下游ERK信号的激活也调节了MMP7的转录激活，从而确定了肿瘤细胞增殖的一种新的前驱机制。
Previously, we showed that ACh-induced proliferation of human colon cancer cells is mediated by transactivation of epidermal growth factor (EGF) receptors (EGFRs). In the present study, we elucidate the molecular mechanism underlying this action. ACh-induced proliferation of H508 colon cancer cells, which express exclusively M3 muscarinic receptors (M(3)Rs), was attenuated by anti-EGFR ligand binding domain antibody, a broad-spectrum matrix metalloproteinase (MMP) inhibitor, anti-MMP7 antibody, a diphtheria toxin analog that blocks release of an EGFR ligand [heparin-binding EGF-like growth factor (HBEGF)], and anti-HBEGF antibody. Conditioned media from ACh-treated H508 cells induced proliferation of SNU-C4 colon cancer cells that express EGFR but not M3R. These actions were attenuated by an EGFR inhibitor and by anti-EGFR and anti-HBEGF antibodies. In H508, but not SNU-C4, colon cancer cells, ACh caused a striking dose- and time-dependent increase in levels of MMP7 mRNA and MMP7 protein. Similarly, ACh induced robust MMP1 and MMP10 gene transcription. ACh-induced MMP1, MMP7, and MMP10 gene transcription was attenuated by atropine, anti-EGFR antibody, and chemical inhibitors of EGFR and ERK activation. In contrast, inhibitors of phosphatidylinositol 3-kinase and NF-kappa B activation did not alter MMP gene transcription. Collectively, these findings indicate that MMP7-catalyzed release of HBEGF mediates ACh-induced transactivation of EGFR and consequent proliferation of colon cancer cells. ACh-induced activation of EGFR and downstream ERK signaling also regulates transcriptional activation of MMP7, thereby identifying a novel feed-forward mechanism for neoplastic cell proliferation.