Grimshaw Matthew J, Hagemann Thorsten, Ayhan Ayse, Gillett Cheryl E, Binder Claudia, Balkwill Frances R
Cancer Research UK Translational Oncology Laboratory, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, United Kingdom.
Cancer Res. 2004 Apr 1;64(7):2461-8. doi: 10.1158/0008-5472.can-03-1069.
We have studied the role of endothelins (ET-1, ET-2 and ET-3) and ET receptors (ET-RA and ET-RB) in the invasive capacity of breast tumor cells, which express ET-1 and ET-2 as well as ET-RA and ET-RB. Of five human breast tumor cell lines tested, all expressed mRNAs for ET-1, ET-2, and ET-RB. ET-RA mRNA was expressed by four of five tumor cell lines. Breast tumor cells migrated toward ET-1 and ET-2 but not toward ET-3. Chemotaxis involved signaling via both receptors, and a pertussis toxin-sensitive p42/p44 mitogen-activated protein kinase (MAPK)-mediated pathway that could be inhibited by MAPK kinase (MEK)1/2 antagonists. Chemotaxis toward ETs did not involve p38 or stress-activated protein kinase (SAPK)/Jun N-terminal kinase (JNK) and was not inhibited by hypoxia. Incubation of tumor cells with ET-2 also increased chemotaxis toward the chemokines CXCL12 and CCL21. As well as inducing chemotaxis of tumor cells, ET-1 and ET-2 increased tumor cell invasion through Matrigel. Furthermore, stimulation of macrophage/tumor cell cocultures with ETs led to increased matrix metalloproteinase (MMP)-2 and -9 production by macrophages and a marked increase in invasion of tumor cells. Antagonism of either ET-RA or ET-RB decreased the invasion seen in ET-stimulated cocultures, as did a broad-spectrum MMP inhibitor. Immunohistochemical staining of human breast tumor sections showed increased ET and ET receptor protein expression by tumor cells in invasive ductal carcinoma compared with normal breast tissue or ductal carcinoma in situ. Furthermore, tumor cell ET and receptor expression was stronger at the invasive margin of invasive ductal carcinomas, in the lymphovascular space, and in lymph node metastases. ET expression often colocalized with ET-RB expression in all neoplastic tissue indicating a possible autocrine action of ETs. We suggest that expression of ETs and their receptors by human breast tumors, particularly in conjunction with a high macrophage infiltrate, may have a role in the progression of breast cancer and the invasion of tumor cells.
我们研究了内皮素（ET-1、ET-2和ET-3）及ET受体（ET-RA和ET-RB）在表达ET-1、ET-2以及ET-RA和ET-RB的乳腺肿瘤细胞侵袭能力中的作用。在所检测的5种人乳腺肿瘤细胞系中，所有细胞系均表达ET-1、ET-2和ET-RB的mRNA。5种肿瘤细胞系中有4种表达ET-RA mRNA。乳腺肿瘤细胞向ET-1和ET-2迁移，但不向ET-3迁移。趋化作用涉及通过两种受体的信号传导，以及一种对百日咳毒素敏感的p42/p44丝裂原活化蛋白激酶（MAPK）介导的途径，该途径可被MAPK激酶（MEK）1/2拮抗剂抑制。对ETs的趋化作用不涉及p38或应激激活蛋白激酶（SAPK）/Jun氨基末端激酶（JNK），且不受缺氧抑制。用ET-2孵育肿瘤细胞也增加了对趋化因子CXCL12和CCL21的趋化作用。除了诱导肿瘤细胞趋化作用外，ET-1和ET-2还增加了肿瘤细胞通过基质胶的侵袭。此外，用ETs刺激巨噬细胞/肿瘤细胞共培养物导致巨噬细胞产生基质金属蛋白酶（MMP）-2和-9增加，以及肿瘤细胞侵袭显著增加。ET-RA或ET-RB的拮抗剂均可降低ET刺激的共培养物中的侵袭，广谱MMP抑制剂也有同样效果。人乳腺肿瘤切片的免疫组织化学染色显示，与正常乳腺组织或原位导管癌相比，浸润性导管癌中的肿瘤细胞ET和ET受体蛋白表达增加。此外，肿瘤细胞ET和受体表达在浸润性导管癌的侵袭边缘、淋巴管腔和淋巴结转移处更强。在所有肿瘤组织中，ET表达常与ET-RB表达共定位，表明ETs可能存在自分泌作用。我们认为，人乳腺肿瘤中ETs及其受体的表达，尤其是与高巨噬细胞浸润相结合时，可能在乳腺癌进展和肿瘤细胞侵袭中起作用。
