Targeting MT-MMPs in Cancer Progression

描述（由申请人提供）：本提案中概述的研究是我们为实现在癌症进展过程中选择性抑制基质金属蛋白酶（MMP）活性的新方法的长期目标而努力的延续。在之前的资助期内，我们专注于明胶酶，MMP-2和MMP-9，我们报道了第一个基于机制的明胶酶抑制剂SB-3CT的成功开发和表征，并证明了其在各种肿瘤模型小鼠中的有效性。我们的选择性MMP抑制剂设计方法为该领域提供了一个起点。我们现在建议开发这种方法来有效和选择性地抑制膜型MMPs (MT-MMP)，这是膜锚定MMPs的一个亚家族，由于其在癌细胞侵袭中的关键作用，在过去的五年里受到了相当大的关注。这一新信息突出了MT-MMPs作为有希望的治疗靶点值得进一步探索。然而，为了实现这一目标，迫切需要有效和选择性的MT-MMP抑制剂，这是目前缺失的。我们实验室的初步证据表明，开发基于新机制的MT1-MMP抑制剂具有巨大的潜力。此外，一个新的抑制剂库已经被构思出来，这将允许发现基于SB-3CT分子模板的MT-MMPs更具选择性的基于机制的抑制剂。最后，为了帮助检测癌症组织中的活性MMPs，我们合成并测试了一种抑制剂栓系树脂，该树脂可用于确定癌症进展和抑制剂治疗期间活性蛋白酶的水平。在这里，我们建议继续我们的努力，使用生化和生物学研究的综合方法来鉴定和抑制MT-MMPs。具体来说，我们将(1)确定基于选择性机制的跨膜MT-MMP抑制剂，(2)验证MT-MMP抑制剂在MT-MMP依赖的细胞外蛋白水解细胞系统中的抑制特性，(3)在癌症动物模型中测试MT-MMP抑制剂，以及(4)监测肿瘤组织中MT-MMP/明胶酶轴的活性形式，作为肿瘤发展和MT-MMP抑制剂治疗的功能。本应用的结果将有助于共同努力开发新的和合理的方法来控制MT-MMPs介导的癌症组织中不调节的蛋白质水解。公共卫生相关性：肿瘤扩散和转移仍然是癌症患者死亡的主要原因。因此，了解促进这些过程的生物学因素，开发旨在减少肿瘤扩散的治疗方法具有重要的临床意义。

DESCRIPTION (provided by applicant): The studies outlined in this proposal are a continuation of our effort towards achieving the long-term goal of developing novel approaches to selective inhibition of matrix metalloproteinase (MMP) activity during cancer progression. In the previous funding period we focused on the gelatinases, MMP-2 and MMP-9 and we reported the successful development and characterization of the first mechanism-based gelatinase inhibitor, SB-3CT, and demonstrated its effectiveness in various tumor models in mice. Our approach to selective MMP inhibitor design has provided a point of departure for the field. We now propose to develop this approach for effective and selective inhibition of membrane-type MMPs (MT-MMP), a subfamily of membrane-anchored MMPs that has received considerable attention in the last five years due to their key roles in cancer cell invasion. This new information highlights the MT-MMPs as promising therapeutic targets that deserve further exploration. However, to achieve this goal there is critical need for effective and selective MT-MMP inhibitors, which are currently missing. Preliminary evidence from our laboratory demonstrates the development of new mechanism-based MT1-MMP inhibitors with great potential. Also, a novel inhibitor library has been conceived, which will permit discovery of more selective mechanism-based inhibitors for MT-MMPs based on the molecular template of SB-3CT. Finally, to aid in the detection of active MMPs in cancer tissues, we have synthesized and tested an inhibitor-tethered resin, which can be used to ascertain the level of active protease during cancer progression and inhibitor treatment. Here we propose to continue our effort using a comprehensive approach of biochemical and biological studies for identification and inhibition of MT-MMPs. Specifically, we will (1) Identify selective mechanism-based inhibitors for transmembrane MT-MMPs, (2) Validate the inhibitory properties of the MT-MMP inhibitors in cellular systems of MT-MMP-dependent pericellular proteolysis, (3) Test the MT-MMP inhibitors in animal models of cancer, and (4) Monitor active forms of the MT-MMP/gelatinase axis in tumor tissues as a function of tumor development and MT-MMP inhibitor treatment. The results of the present application will contribute to the collective endeavor of developing novel and rational approaches for controlling unregulated proteolysis in cancer tissues mediated by MT-MMPs. PUBLIC HEALTH RELEVANCE: Tumor dissemination and metastasis remain the major cause of death in cancer patients. Therefore, understanding the biological factors promoting these processes and developing therapies aimed at reducing tumor spread is of great clinical significance.