2012年12月18日訊 /生物谷BIOON/ MIT 開發一項新的技術能夠早期診斷癌症。Sangeeta Bhatia領導的研究小組開發出一種納米粒子,這種粒子能夠靶向到腫瘤細胞,通過和腫瘤細胞相互作用產生成千上萬的生物標記,這種標記能夠在病人尿液中很容易的被檢測到。
腫瘤細胞能夠產生一些正常細胞沒有的蛋白,這些蛋白溶解在血液中很難被檢測到。如卵巢癌具有特殊的生物標記,但是現有技術只有在卵巢癌形成8-10年後才能檢測到這種標記。Bhatia 說,由於生物標記量很少,所以很難被檢測到,如果採用一種能夠放大標記的方法,就能夠解決這個問題。
腫瘤細胞大量表達一種稱之為MMP的蛋白酶,這種蛋白酶能夠講解胞外基質蛋白,從而使腫瘤細胞逃離原有位置四處散布。
研究人員將能夠被MMP降解的短肽包埋到納米粒子中,納米粒子聚集到腫瘤區域後,MMP將納米粒子上的短肽降解到血液中。這些短肽在腎臟中聚集,並通過尿液排出。而這些短肽很容易用質譜的方法檢測到。
這種新方法克服了腫瘤生物標記物濃度低的限制,能夠大大的提前的腫瘤早期診斷時間。(生物谷Bioon.com)
Mass-encoded synthetic biomarkers for multiplexed urinary monitoring of disease
Gabriel A Kwong, Geoffrey von Maltzahn, Gayathree Murugappan, Omar Abudayyeh, Steven Mo, Ioannis A Papayannopoulos, Deanna Y Sverdlov, Susan B Liu, Andrew D Warren, Yury Popov, Detlef Schuppan, Sangeeta N Bhatia
Biomarkers are becoming increasingly important in the clinical management of complex diseases, yet our ability to discover new biomarkers remains limited by our dependence on endogenous molecules. Here we describe the development of exogenously administered 'synthetic biomarkers' composed of mass-encoded peptides conjugated to nanoparticles that leverage intrinsic features of human disease and physiology for noninvasive urinary monitoring. These protease-sensitive agents perform three functions in vivo: they target sites of disease, sample dysregulated protease activities and emit mass-encoded reporters into host urine for multiplexed detection by mass spectrometry. Using mouse models of liver fibrosis and cancer, we show that these agents can noninvasively monitor liver fibrosis and resolution without the need for invasive core biopsies and substantially improve early detection of cancer compared with current clinically used blood biomarkers. This approach of engineering synthetic biomarkers for multiplexed urinary monitoring should be broadly amenable to additional pathophysiological processes and point-of-care diagnostics.