Mice bearing orthotopic LM-PmC mouse pancreatic tumors implanted 1 week earlier received intravenous injections of 4 μmol/kg of iRGD, a conventional non-CendR RGD peptide (CRGDC), iRGDD, or iNGR (CRNGRGPDC), or PBS, every other day for 14 days. n = 10 per group. One of two experiments that gave similar results is shown. A, The mice were necropsied after the treatment and viewed under a fluorescence imager. PT, primary tumor; S, stomach. B, Metastatic burden analyzed by quantification of fluorescence intensity with Image J. C, Weight of primary tumors. Error bars, mean ± SEM. Statistical analyses were performed with ANOVA: n.s., not significant; *P < 0.05; **P < 0.01.