Fig. 2: MicroPET imags of 68Ga-P-LPK in U87 and HCT116 tumor–bearing nude mice.
From: Anti-tumor effects of P-LPK-CPT, a peptide-camptothecin conjugate, in colorectal cancer
a Whole-body coronal microPET images of U87 and HCT116 tumor-bearing mice (n = 4) at 30, 60, and 120 min after injection of 68Ga-P-LPK or 68Ga-P-CON (white circles, U87 tumors; yellow circles, HCT116 tumors). The quantification values of tumor were showed in the lower right corner of mice. b, c In contrast with 68Ga-P-CON, the T/NT ratios of 68Ga-P-LPK was significantly increased in the HCT116 tumor-bearing mice (b) but not in U87 tumor-bearing mice (c), suggesting that 68Ga-P-LPK specifically binds to CRC tissues (n = 4, means ± SD, HCT116 30 min: 68Ga-P-CON vs 68Ga-P-LPK, p < 0.0001; 60 min: 68Ga-P-CON vs 68Ga-P-LPK, p < 0.0001; 120 min: 68Ga-P-CON vs 68Ga-P-LPK, p < 0.0001) (****p < 0.0001). The prominent uptake of 68Ga-peptide was observed at the bladder at early time points (30 min), suggesting that this tracer may be excreted through the urinary route. d, e After blocking with unlabeled peptide, the T/NT ratios was significantly reduced at 60 min and 120 min (n = 3, means ± SD, 30 min: Unblock vs block, p = 0.7512; 60 min: Unblock vs block, p < 0.0001; 120 min: Unblock vs block, p < 0.0001) (****p < 0.0001).
