Synthesis, in vitro screening and in vivo evaluation of cyclic RGD analogs cyclized through oxorhenium and oxotechnetium coordination
摘要:
A library of RGD tripeptide analogs cyclized through oxorhenium coordination by an NS2/S chelation motif was synthesized. Screening towards integrins alpha V beta 3, alpha llb beta 3 and alpha V beta 5 led to the identification of 6 oxorhenium complexes that bind to integrin alpha V beta 3 in the submicromolar range. In vivo evaluation of five of the corresponding oxotechnetium complexes using nude mice bearing a U87MG human tumor xenograft showed a significant and specific accumulation of radioactivity inside the tumor. The best results in vivo were obtained with complexes Tc-16 and Tc-50 that displayed a higher tumor accumulation and a lower distribution in other tissues relative to a reference cyclopentapeptide tracer. (C) 2011 Elsevier Masson SAS. All rights reserved.
Cyclicpeptides have been expected to be one of the modalities of intracellular protein–protein interaction (PPI) inhibitors, but they are generally known to have low cell membranepermeability. In this study, we focused on the conformation of cyclicpeptides in the cell membrane to determine the requirement for their cell membranepermeability through passive diffusion. Utilizing the requirement,
环肽被认为是细胞内蛋白质-蛋白质相互作用(PPI)抑制剂的一种形式,但众所周知,它们的细胞膜通透性较低。在本研究中,我们重点关注细胞膜中环肽的构象,以确定其通过被动扩散对细胞膜渗透性的要求。利用这一要求,我们通过计算化学寻找对MDMX具有高亲和力的结构,并获得了环肽19 ( P app = 0.80 × 10 –6 cm s –1 ,IC 50 = 0.07 μM)。