Carreiras F, Lehmann M, Sichel F, Marvaldi J, Gauduchon P, Le Talaer J Y
Laboratoire de Cancérologie Expérimentale, Centre F. Baclesse, Caen, France.
Int J Cancer. 1995 Nov 15;63(4):530-6. doi: 10.1002/ijc.2910630413.
Accumulating evidence suggests that integrins, which participate in many complex cellular processes, are important for tumor progression and metastasis. In order to understand the role of these cell-surface receptors and of their ligands in the biological behavior of ovarian tumor cells, we have examined the expression of integrins in the human ovarian-adenocarcinoma cell line IGROV1. These cells expressed the alpha v sub-unit and used it to attach on vitronectin (Vn). A monoclonal antibody (MAb) (69-6-5) specific to alpha v blocked the attachment of IGROV1 cells on Vn and fibrinogen (Fg), but not on fibronectin (FN) and other adhesive ligands. Immunoprecipitation of surface biotinylated cells followed by Western blotting showed that the alpha v sub-unit was associated with beta 3, but not with beta 1, beta 5 or beta 6. When cells were cultivated on glass coverslips or on Vn sub-stratum in serum-free medium, immunofluorescence staining with MAb 69-6-5 revealed the presence of alpha v at cell-cell contacts and at focal contacts, supporting its active participation in adhesion as part of a functional heterodimer. Furthermore, immunofluorescence data showed the presence of Vn as a fibrillar network in IGROV1 cells cultivated on FN-coated slides. These results suggest that alpha v beta 3 and its Vn ligand may play a important role in the behavior of ovarian epithelial tumors.
越来越多的证据表明，参与许多复杂细胞过程的整合素对肿瘤进展和转移至关重要。为了了解这些细胞表面受体及其配体在卵巢肿瘤细胞生物学行为中的作用，我们检测了人卵巢腺癌细胞系IGROV1中整合素的表达。这些细胞表达αv亚基，并利用它附着在玻连蛋白（Vn）上。一种针对αv的单克隆抗体（MAb）（69-6-5）可阻断IGROV1细胞在Vn和纤维蛋白原（Fg）上的附着，但不能阻断在纤连蛋白（FN）和其他黏附配体上的附着。对表面生物素化细胞进行免疫沉淀后进行蛋白质印迹分析表明，αv亚基与β3相关联，但与β1、β5或β6不相关联。当细胞在无血清培养基中的玻璃盖玻片或Vn基质上培养时，用MAb 69-6-5进行免疫荧光染色显示，αv存在于细胞间接触点和黏着斑处，支持其作为功能性异二聚体的一部分积极参与黏附过程。此外，免疫荧光数据显示，在FN包被载玻片上培养的IGROV1细胞中，Vn以纤维状网络形式存在。这些结果表明，αvβ3及其Vn配体可能在卵巢上皮肿瘤的行为中起重要作用。
