Cell permeable PET imaging probe could detect prostate cancer
An arginine-rich cell permeable peptide could be used as a PET imaging probe for specific detection of distant prostate cancer metastases, according to a study published on March 11 in the journal Amino Acids.

Guiyang Hao, PhD, a postdoctoral researcher at the University of Texas Southwestern Medical Center in Dallas, and colleagues evaluated the optimal length of arginine-rich peptides by the cell uptake efficiency of three fluorescein isothiocyanate (FITC)-tagged oligoarginines in four human prostate cell lines.

Of the three oligoarginines, NH(2)GR(11) showed the highest cell uptake and internalization efficiency with its subcellular localization in cytosol, according to the researchers.

Hao and colleagues performed biodistribution of FITC-NHGR(11) in nude mice displaying the preferential accumulation of FITC-NHGR(11) in the prostate tissue and elevated uptake of this peptide in tumors as compared to other organs.

In vivo pharmacokinetics evaluated with 64-Cu-labeled NH (2)GR(11) showed that the peptide was rapidly cleared from the blood with half-life of 10.7 minutes and its elimination half-life was 17.2 hours, they found.