2015年4月24日訊 /生物谷BIOON/ -- wnt信號包括β catenin依賴性的經典途徑和β catenin非依賴性的非經典途徑,在調節動物發育和維持穩態方面具有重要作用,wnt信號失調會引起包括癌症在內的多種疾病發生。
wnt-frz之間發生相互作用能夠激活非經典途徑,但對於經典途徑沒有影響,這一過程的發生需要wnt共受體LRP5/6的作用。近日,來自同濟大學的研究人員在國際學術期刊nature communication在線發表了他們關於LRP5/6 在frizzled介導的腫瘤轉移中發揮抑制作用的最新研究進展。
在該項研究中,研究人員發現wnt受體frizzled及其共受體LRP5/6能夠發生直接相互作用,並且這種相互作用受到LRP6胞外結構域的調節作用。同時,通過與frz直接結合,LRP5/6能夠抑制frz介導的wnt非經典途徑激活並進一步抑制wnt非經典途徑介導的腫瘤轉移過程。研究人員通過體外實驗證實敲低內源性LRP5/6能夠促進非侵襲性腫瘤細胞遷移,利用LRP6胞外段重組蛋白進行處理可以抑制侵襲性腫瘤細胞的體外遷移和體內轉移。同時,細胞膜LRP5/6的表達水平與小鼠和人類乳腺癌轉移呈負相關性。
這項研究首次揭示了膜受體frizzled與LRP5/6之間的相互作用,同時發現了LRP5/6抑制wnt非經典信號途徑的分子機制,為LRP6胞外結構域在抑制腫瘤轉移方面的臨床應用提供了重要生物學基礎。(生物谷Bioon.com)
LRP5/6 directly bind to Frizzled and prevent Frizzled-regulated tumour metastasis
Dan-ni Ren,Jinxiao Chen,Zhi Li,Hongwei Yan,Yan Yin,Da Wo,Jiankang Zhang,Luoquan Ao,Bo Chen,Takashi K. Ito,Yihan Chen,Zhongmin Liu,Yongyong Li,Jianhua Yang,Xiaoling Lu,Yi Peng,Linghui Pan,Yongxiang Zhao,Shangfeng Liu & Weidong Zhu
How Wnt signalling including canonical and non-canonical pathways are initiated at the cell surface is not completely understood. Here we report that Wnt receptor Frizzled (Frz) and theco-receptors LRP5 and LRP6 (LRP5/6) directly interact with each other and this interaction is regulated by the LRP6 ectodomain. Importantly, through direct binding to Frz, LRP5/6 are able to prevent Frz-regulated non-canonical pathway activation and further non-canonical pathway-mediated tumour metastasis. Knockdown of endogenous LRP5/6 promotes otherwise-nonaggressive tumour cells to migrate in vitro, whereas a soluble recombinant protein of LRP6 ectodomain suppresses migration and metastasis of otherwise-aggressive tumour cells in vitro and in vivo. Furthermore, the expression level of membrane LRP5/6 correlates inversely with metastasis in mouse and human breast cancer. Our study suggests a previously unrecognized mode of receptor interaction, revealing the mechanism of LRP5/6 in inhibition of non-canonical pathway, and a possible clinical use of the LRP6 ectodomain to impede metastasis.