Chen Y Q, Trikha M, Gao X, Bazaz R, Porter A T, Timar J, Honn K V
Department of Pathology, Wayne State University, Detroit, MI 48202, USA.
Int J Cancer. 1997 Aug 7;72(4):642-8. doi: 10.1002/(sici)1097-0215(19970807)72:4<642::aid-ijc16>3.0.co;2-d.
The integrin alphaIIb beta3 is a membrane receptor which was considered to be expressed only in cells of megakaryocytic lineage. We have shown that alphaIIb beta3 is expressed in mouse melanoma B16a cells, and in human prostate adenocarcinoma cells. The purpose of this study was to determine whether the megakaryocytic product alphaIIb beta3 was functionally expressed in other non-megakaryocyte lineage tumor cells. By using the reverse transcription polymerase chain reaction (RT-PCR), we have obtained data demonstrating that alphaIIb beta3 is expressed in a variety of tumor cell lines (17) derived from different species (human, rat and mouse) and of different histological origins (skin, blood, lung, liver, kidney, cervix, colon, bladder, breast and prostate). Immunostaining of tumor cells with a monoclonal antibody (MAb) to alphaIIb beta3 demonstrates that alphaIIb beta3 protein is also expressed in tumor cells. A protein kinase C activator PMA stimulates adhesion of tumor cells to fibronectin and fibrinogen, and this stimulated adhesion is blocked by a function-blocking MAb directed to alphaIIb beta3. Our results indicate that the megakaryocytic gene product alphaIIb beta3 integrin is widely expressed among tumor cells of non-megakaryocytic lineage, suggesting that ectopic expression of this integrin may play an important role in tumor progression.
整合素αIIbβ3是一种膜受体，曾被认为仅在巨核细胞系的细胞中表达。我们已经证明αIIbβ3在小鼠黑色素瘤B16a细胞和人前列腺腺癌细胞中表达。本研究的目的是确定巨核细胞产物αIIbβ3在其他非巨核细胞系肿瘤细胞中是否有功能表达。通过使用逆转录聚合酶链反应（RT-PCR），我们获得的数据表明αIIbβ3在多种源自不同物种（人、大鼠和小鼠）且组织学来源不同（皮肤、血液、肺、肝、肾、宫颈、结肠、膀胱、乳腺和前列腺）的肿瘤细胞系（17种）中表达。用抗αIIbβ3单克隆抗体（MAb）对肿瘤细胞进行免疫染色表明αIIbβ3蛋白也在肿瘤细胞中表达。蛋白激酶C激活剂佛波酯（PMA）刺激肿瘤细胞与纤连蛋白和纤维蛋白原的黏附，且这种刺激的黏附被针对αIIbβ3的功能阻断性MAb所阻断。我们的结果表明巨核细胞基因产物αIIbβ3整合素在非巨核细胞系肿瘤细胞中广泛表达，提示这种整合素异源表达可能在肿瘤进展中起重要作用。
