OBJECTIVETo investigate the effects of peptide YY (PYY) on subcutaneous transplantation tumor of human hepatoma in nude mice and preliminarily explore the mechanisms.

METHODSHepG2 human hepatic carcinoma cells were injected into nude mice subcutaneously, and the resultant tumor were taken and prepared into small tissue blocks. The tissue blocks were implanted subcutaneously into nude mice to establish mouse models bearing human hepatoma. Thirty-two such mouse models were assigned equally into 4 groups to receive subcutaneous PYY injection at a high or low dose, intraperitoneal injection of floxuridine (positive control group), or subcutaneous normal saline injection (negative control group). The general condition of the tumor-bearing mice and the growth of the tumors were observed.

RESULTSCompared with the negative control group, the high- and low-dose PYY groups showed reduced gross tumor volume, lowered serum AFP, tumor weight, and cAMP content in the tumor tissue (P<0.05).

CONCLUSIONPYY can inhibit the growth of subcutaneous hepatoma in nude mice, which might be associated with the reduction of cAMP content in the tumors following PYY treatment.