The Skaggs Institute for Chemical Biology, Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA.
Mol Pharm. 2010 Feb 1;7(1):245-53. doi: 10.1021/mp900236t.
Despite significant progress and notable successes in tumor therapy, malignant disease remains an extremely difficult problem in today's health care setting. There is, however, an increasing application of new therapies targeting proteins specifically upregulated on tumor cells. These innovative therapeutic approaches are aimed at molecules that contribute to malignant development and progression but spare normal tissues. The CUB domain containing protein 1 (CDCP1) is such a tumor-associated protein and, thus, a potential candidate for targeted cancer immunotherapy. Herein, we describe the generation of function-blocking human antibodies against CDCP1 that were obtained from human scFv phage display libraries using subtractive panning protocols on CDCP1 expressing cancer cells and immunopurified CDCP1 protein. One of the isolated anti-CDCP1 antibodies, namely, C20Fc, efficiently blocked experimental metastasis of human carcinoma cells, including HeLa cells stably transfected with CDCP1 and prostate carcinoma cells PC-hi/diss naturally expressing CDCP1, in both chick embryo and mouse model systems. The C20Fc antibody also reduced colony formation of CDCP1 expressing cells in a soft agar assay for anchorage-independent cell growth. Specific targeting of CDCP1 by C20Fc mediated the delivery of a toxin-conjugated antibody complex, thus, providing evidence for antibody internalization and specific killing of CDCP1-positive tumor cells. Our findings indicate a functional role for CDCP1 in human cancer and underscore the therapeutic potential of function-blocking anti-CDCP1 antibodies targeting both primary and metastatic carcinoma cells.
尽管在肿瘤治疗方面取得了重大进展和显著成就，但恶性疾病仍然是当今医疗保健领域的一个极其困难的问题。然而，针对肿瘤细胞特异性上调的蛋白质的新疗法的应用越来越多。这些创新的治疗方法针对的是促进恶性发展和进展但不影响正常组织的分子。CUB 结构域蛋白 1（CDCP1）就是这样一种肿瘤相关蛋白，因此是靶向癌症免疫治疗的潜在候选者。在此，我们描述了使用针对表达 CDCP1 的癌细胞的消减淘选方案和免疫纯化的 CDCP1 蛋白，从人 scFv 噬菌体展示文库中获得针对 CDCP1 的功能阻断性人源抗体。分离出的一种抗 CDCP1 抗体，即 C20Fc，能够有效地阻断人癌细胞的实验性转移，包括稳定转染 CDCP1 的 HeLa 细胞和自然表达 CDCP1 的前列腺癌细胞 PC-hi/diss，在鸡胚和小鼠模型系统中均如此。C20Fc 抗体还减少了在软琼脂测定中用于锚定非依赖性细胞生长的表达 CDCP1 的细胞的集落形成。C20Fc 通过特异性靶向 CDCP1 介导了与毒素偶联的抗体复合物的传递，从而为抗体内化和特异性杀伤 CDCP1 阳性肿瘤细胞提供了证据。我们的研究结果表明 CDCP1 在人类癌症中的功能作用，并强调了针对原发性和转移性癌细胞的功能阻断性抗 CDCP1 抗体的治疗潜力。
