Suppression of Aggrus/podoplanin‐induced platelet aggregation and pulmonary metastasis by a single‐chain antibody variable region fragment

Cancer Medicine

Kenichi Miyata³  Satoshi Takagi³  Shigeo Sato³  Hiroshi Morioka¹  Kiyotaka Shiba²  Tamiko Minamisawa²  Miho Takami³ 

[1] Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan;Division of Protein Engineering, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan;Division of Experimental Chemotherapy, The Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan

关键词: Aggrus/podoplanin;    phage display;    platelet aggregation;    scFv;    tumor metastasis;   

DOI  :  10.1002/cam4.320

来源: Wiley

【 摘 要 】

Abstract

Almost all highly metastatic tumor cells possess high platelet aggregating abilities, thereby form large tumor cell-platelet aggregates in the microvasculature. Embolization of tumor cells in the microvasculature is considered to be the first step in metastasis to distant organs. We previously identified the platelet aggregation-inducing factor expressed on the surfaces of highly metastatic tumor cells and named as Aggrus. Aggrus was observed to be identical to the marker protein podoplanin (alternative names, T1α, OTS-8, and others). Aggrus is frequently overexpressed in several types of tumors and enhances platelet aggregation by interacting with the platelet receptor C-type lectin-like receptor 2 (CLEC-2). Here, we generated a novel single-chain antibody variable region fragment (scFv) by linking the variable regions of heavy and light chains of the neutralizing anti-human Aggrus monoclonal antibody MS-1 with a flexible peptide linker. Unfortunately, the generated KM10 scFv failed to suppress Aggrus-induced platelet aggregation in vitro. Therefore, we performed phage display screening and finally obtained a high-affinity scFv, K-11. K-11 scFv was able to suppress Aggrus-induced platelet aggregation in vitro. Moreover, K-11 scFv prevented the formation of pulmonary metastasis in vivo. These results suggest that K-11 scFv may be useful as metastasis inhibitory scFv and is expected to aid in the development of preclinical and clinical examinations of Aggrus-targeted cancer therapies.

【 授权许可】

CC BY   
© 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

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