Matrix metalloproteases (MMPs) are a large family of zinc-dependent endopeptidases involved in a diverse set of physiological and pathological processes, most notably in cancer. Current methods for imaging and quantifying MMP activity lack sufficient selectivity and spatiotemporal resolution to allow studies of specific MMP function in vivo. Previously, we reported a strategy for selective targeting of MMPs by engineering a functionally silent cysteine mutation that enables highly specific covalent modification by a designed activity-based probe. Here, we describe the translation of that technology into a mouse model of breast cancer and subsequent demonstration of the utility of the approach for studies of MMP-14 activation in the tumor microenvironment. Using this approach, we find that MMP-14 is active in late stage tumors and is predominantly associated with stromal cell populations that have been activated by specific signaling molecules (e.g., TGFβ) produced by tumor cells. Our data demonstrate the applicability of this approach for studies of MMP function in whole organisms and identify important regulatory mechanisms for MMP-14 activity in the tumor microenvironment.

中文翻译：

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在多细胞模型中内源表达的MMP-14选择性活性分析的化学工具

基质金属蛋白酶（MMPs）是锌依赖性内肽酶的一大家族，参与多种生理和病理学过程，特别是在癌症中。当前的成像和定量MMP活性的方法缺乏足够的选择性和时空分辨率，无法进行体内特定MMP功能的研究。以前，我们报道了通过设计功能性沉默的半胱氨酸突变来选择性靶向MMP的策略，该突变使半胱氨酸突变能够通过设计的基于活性的探针进行高度特异性的共价修饰。在这里，我们描述了将该技术翻译成乳腺癌的小鼠模型，并随后证明了该方法在肿瘤微环境中研究MMP-14激活的实用性。使用这种方法，我们发现MMP-14在晚期肿瘤中具有活性，并且主要与已被肿瘤细胞产生的特定信号分子（例如TGFβ）激活的基质细胞群相关。我们的数据证明了该方法在整个生物体中MMP功能研究中的适用性，并确定了肿瘤微环境中MMP-14活性的重要调控机制。