Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, PO Box 653, Beer-Sheva 84105, Israel.
The National Institute for Biotechnology in the Negev, PO Box 653, Beer-Sheva 84105, Israel.
Biochem J. 2021 Mar 12;478(5):1139-1157. doi: 10.1042/BCJ20200628.
Crosstalk of the oncogenic matrix metalloproteinase-9 (MMP9) and one of its ligands, CD44, involves cleavage of CD44 by the MMP9 catalytic domain, with the CD44-MMP9 interaction on the cell surface taking place through the MMP9 hemopexin domain (PEX). This interaction promotes cancer cell migration and invasiveness. In concert, MMP9-processed CD44 induces the expression of MMP9, which degrades ECM components and facilitates growth factor release and activation, cancer cell invasiveness, and metastasis. Since both MMP9 and CD44 contribute to cancer progression, we have developed a new strategy to fully block this neoplastic process by engineering a multi-specific inhibitor that simultaneously targets CD44 and both the catalytic and PEX domains of MMP9. Using a yeast surface display technology, we first obtained a high-affinity inhibitor for the MMP9 catalytic domain, which we termed C9, by modifying a natural non-specific MMP inhibitor, N-TIMP2. We then conjugated C9 via a flexible linker to PEX, thereby creating a multi-specific inhibitor (C9-PEX) that simultaneously targets the MMP9 catalytic and PEX domains and CD44. It is likely that, via its co-localization with CD44, C9-PEX may compete with MMP9 localization on the cell surface, thereby inhibiting MMP9 catalytic activity, reducing MMP9 cellular levels, interfering with MMP9 homodimerization, and reducing the activation of downstream MAPK/ERK pathway signaling. The developed platform could be extended to other oncogenic MMPs as well as to other important target proteins, thereby offering great promise for creating novel multi-specific therapeutics for cancer and other diseases.
致癌基质金属蛋白酶-9（MMP9）与其配体之一 CD44 的串扰涉及 MMP9 催化结构域对 CD44 的裂解，细胞表面的 CD44-MMP9 相互作用通过 MMP9 血红素结合结构域（PEX）发生。这种相互作用促进了癌细胞的迁移和侵袭。协同作用下，MMP9 处理的 CD44 诱导 MMP9 的表达，MMP9 降解 ECM 成分并促进生长因子释放和激活、癌细胞侵袭和转移。由于 MMP9 和 CD44 均有助于癌症进展，我们开发了一种新策略，通过构建一种同时针对 CD44 以及 MMP9 的催化和 PEX 结构域的多特异性抑制剂来完全阻断这种肿瘤过程。我们首先使用酵母表面展示技术，通过修饰天然非特异性 MMP 抑制剂 N-TIMP2，获得了 MMP9 催化结构域的高亲和力抑制剂 C9。然后，我们通过柔性接头将 C9 与 PEX 连接，从而创建了一种同时针对 MMP9 催化和 PEX 结构域以及 CD44 的多特异性抑制剂（C9-PEX）。C9-PEX 可能通过与 CD44 共定位，与 MMP9 在细胞表面的定位竞争，从而抑制 MMP9 的催化活性、降低 MMP9 的细胞水平、干扰 MMP9 同源二聚化并减少下游 MAPK/ERK 通路信号的激活。该开发平台可扩展到其他致癌 MMP 以及其他重要的靶蛋白，从而为开发用于癌症和其他疾病的新型多特异性治疗药物提供了巨大的前景。
