侵袭伪足促进癌细胞外渗，但侵袭伪足特异性蛋白酶（例如 MT1-MMP）被称为侵袭伪足的分子机制尚不清楚。质谱和免疫沉淀用于鉴定转移性乳腺癌细胞中 MT1-MMP 的相互作用因子。鉴定后，使用 siRNA 和小分子抑制剂来评估这些相互作用物对细胞侵袭性的影响。鸡胚绒毛尿囊膜 (CAM) 模型用于评估体内外渗和侵入伪足的形成。在转移性乳腺癌细胞中，MT1-MMP 被发现与 plectin（一种细胞接头和支架蛋白）相关。 plectin 和 MT1-MMP 之间的复合物形成引发了侵袭伪足形成，这是一种我们称为 iplectin 的亚型（i = invadopodial）。 iPlectin 将 MT1-MMP 递送至侵袭伪足，对于调节细胞表面酶水平至关重要。用 siRNA 对 plectin 进行基因敲除可减少体外侵袭伪足的形成和细胞侵袭。体内外渗效率测定和活体成像表明，iplectin 是侵袭伪足超微结构的关键贡献者，并且对于外渗至关重要。使用小分子 Plecstatin-1 (PST-1) 对 plectin 进行药理学抑制可消除 MT1-MMP 向侵袭伪足的递送和外渗效率。通过破坏 MT1-MMP 和 iplectin 之间的相互作用，可以实现针对侵袭伪足的抗转移治疗方法。NCT04608357.© 2024 年。作者获得 Springer Nature Limited 的独家许可。

Invadopodia facilitate cancer cell extravasation, but the molecular mechanism whereby invadopodia-specific proteases such as MT1-MMP are called to invadopodia is unclear.Mass spectrometry and immunoprecipitation were used to identify interactors of MT1-MMP in metastatic breast cancer cells. After identification, siRNA and small molecule inhibitors were used to assess the effect these interactors had on cellular invasiveness. The chicken embryo chorioallantoic membrane (CAM) model was used to assess extravasation and invadopodia formation in vivo.In metastatic breast cancer cells, MT1-MMP was found to associate with plectin, a cytolinker and scaffolding protein. Complex formation between plectin and MT1-MMP launches invadopodia formation, a subtype we termed iplectin (i = invadopodial). iPlectin delivers MT1-MMP to invadopodia and is indispensable for regulating cell surface levels of the enzyme. Genetic depletion of plectin with siRNA reduced invadopodia formation and cell invasion in vitro. In vivo extravasation efficiency assays and intravital imaging revealed iplectin to be a key contributor to invadopodia ultrastructure and essential for extravasation. Pharmacologic inhibition of plectin using the small molecule Plecstatin-1 (PST-1) abrogated MT1-MMP delivery to invadopodia and extravasation efficiency.Anti-metastasis therapeutic approaches that target invadopodia are possible by disrupting interactions between MT1-MMP and iplectin.NCT04608357.© 2024. The Author(s), under exclusive licence to Springer Nature Limited.