Abstract:
Objective To investigate the inhibitory effect of 90Y-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-Tyr (3)-octreotide (DOTATOC) on the human pancreatic neuroendocrine tumor cell line BON-1.
Methods (1) DOTATOC was labeled with 90Y, and then purified it. (2) The stability of 90Y-DOTATOC was investigated in vitro. (3) The thiazole blue method was used to examine the inhibitory effects of 90Y, DOTATOC, and 90Y-DOTATOC on human pancreatic neuroendocrine tumor cell BON-1 and human pancreatic cholangioma cell PANC-1, and then the cell proliferation inhibition rate was calculated. Negative control group, positive control group (Vincristine, 50 μmol/L), DOTATOC group (25 μmol/L), 90Y group (1.8 MBq/ml), 90Y-DOTATOC high-dose group (90Y dose was 1.8 MBq/ml, DOTATOC concentration was 25 μmol/L), 90Y-DOTATOC medium dose group (90Y dose was 0.37 MBq/ml, DOTATOC concentration was 25 μmol/L), 90Y-DOTATOC low-dose group (90Y dose was 0.074 MBq/ml, DOTATOC concentration was 25 μmol/L) were set up. Independent sample t-test was used for inter group comparison.
Result (1) The labeling rate of the DOTATOC labeled with 90Y was (61.93±3.53)%. Its radiochemical purity was (98.88±0.38)%, its radioactive concentration was 4.6 MBq/ml, and its specific activity was 1.6 GBq/μmol. (2) The radiochemical purity of 90Y-DOTATOC after being placed in physiological saline and 10% bovine serum for 7 days was 97.73% and 97.02%, respectively. (3) After 24 h and 48 h of drug addition, the inhibitory effect of the DOTATOC group on BON-1 cells was significantly increased compared with that of the negative group, and the difference was statistically significant (t=2.654, 3.981, all P<0.05). After 24 h and 48 h of drug addition, the inhibitory effects of the high and medium 90Y-DOTATOC dose groups on BON-1 and PANC-1 cells were superior to that of the DOTATOC group, and the difference was statistically significant (t=2.267–3.852, all P<0.05). After 24 h and 48 h of drug addition, the inhibitory effects of the pure 90Y group on PANC-1 and BON-1 cells were significantly lower than that of the high-dose 90Y-DOTATOC group, and the difference was statistically significant (t=2.698–3.180, all P<0.05).
Conclusion 90Y-DOTATOC exerts a strong inhibitory effect on BON-1 tumor cells and is dose-dependent on 90Y dosage. Compared with using DOTATOC or 90Y alone, 90Y-DOTATOC exhibits better inhibitory effect on BON-1 tumor cells.