Mingqian Tan1,2, Zheng-Rong Lu1
1Case Western Reserve University, Cleveland, OH, United States; 2National Chromatographic Research & Analysis Center, Dalian Institute of Chemical Physics, the Chinese Academy of Sciences, Dalian, Liaoning, China, People's Republic of
A cyclic peptide CLT1-targeted nanoglobular Gd(III)-based contrast agent was evaluated in male mice bearing orthotopic xenograft tumor with MRI. The r1 and r2 relaxivities of the CLT1 targeted agent were 11.63 and 15.73 mM-1s-1 per Gd(III) chelate at 1.5T, respectively. Peptide CLT1 has shown significant accumulation in tumor as compared to a control peptide. The CLT1 targeted contrast agent resulted in strong contrast enhancement in the orthotopic prostate tumor for in vivo MR molecular imaging, while little enhancement was observed in the tumor with the control agent. The results demonstrated that the CLT1-targted nanoglobular contrast agent is effective for in vivo cancer MR molecular imaging in an orthotopic mouse tumor model.