Wong Julin S, Warbrick Emma, Vojtesk Borek, Hill Jeffrey, Lane David P
p53 Laboratory, 8A Biomedical Grove, Immunos #06-06, Singapore, Singapore.
Oncotarget. 2013 Jul;4(7):1019-36. doi: 10.18632/oncotarget.1075.
c-Met is a tyrosine receptor kinase which is activated by its ligand, the hepatocyte growth factor. Activation of c-Met leads to a wide spectrum of biological activities such as motility, angiogenesis, morphogenesis, cell survival and cell regeneration. c-Met is abnormally activated in many tumour types. Aberrant c-Met activation was found to induce tumour development, tumour cell migration and invasion, and the worst and final step in cancer progression, metastasis. In addition, c-Met activation in cells was also shown to confer resistance to apoptosis induced by UV damage or chemotherapeutic drugs. This study describes the development of monoclonal antibodies against c-Met as therapeutic molecules in cancer treatment/diagnostics. A panel of c-Met monoclonal antibodies was developed and characterised by epitope mapping, Western blotting, immunoprecipitation, agonist/antagonist effect in cell scatter assays and for their ability to recognise native c-Met by flow cytometry. We refer to these antibodies as Specifically Engaging Extracellular c-Met (seeMet). seeMet 2 and 13 bound strongly to native c-Met in flow cytometry and reduced SNU-5 cell growth. Interestingly, seeMet 2 binding was strongly reduced at 4oC when compared to 37oC. Detail mapping of the seeMet 2 epitope indicated a cryptic binding site hidden within the c-Met α-chain.
c-Met是一种酪氨酸受体激酶，可被其配体肝细胞生长因子激活。c-Met的激活会引发广泛的生物学活性，如运动性、血管生成、形态发生、细胞存活和细胞再生。c-Met在许多肿瘤类型中被异常激活。研究发现，c-Met的异常激活会诱导肿瘤发展、肿瘤细胞迁移和侵袭，以及癌症进展中最严重的最后一步——转移。此外，细胞中的c-Met激活还显示出对紫外线损伤或化疗药物诱导的细胞凋亡具有抗性。本研究描述了针对c-Met的单克隆抗体作为癌症治疗/诊断中的治疗分子的研发情况。通过表位作图、蛋白质印迹、免疫沉淀、细胞散射试验中的激动剂/拮抗剂效应以及流式细胞术识别天然c-Met的能力，开发并表征了一组c-Met单克隆抗体。我们将这些抗体称为特异性结合细胞外c-Met（seeMet）。seeMet 2和13在流式细胞术中与天然c-Met紧密结合，并抑制SNU-5细胞生长。有趣的是，与37℃相比，seeMet 2在4℃时的结合力大幅降低。seeMet 2表位的详细作图表明，在c-Metα链内隐藏着一个隐蔽的结合位点。
