Inhibition of five xenografted human cancers and two murine cancers by the tripeptide tyroservatide

Abstract

The tripeptide tyroservatide (tyrosyl-seryl-valine, pTyr-Ser-Val-NH2) has been shown to have antitumor effects on experimental hepatocarcinoma. This study aimed to observe the effects of tyroservatide on other five human carcinomas: A549 (nonsmall cell lung carcinoma), BGC-823 (gastric cancer), MCF-7 (breast cancer), K562 (leukemia), A375 (melanoma) and two murine cancers: Lewis lung cancer and B16 (melanoma) in vivo. In vivo nude mice bearing xenografts of five different human tumors or C57BL/6 mice bearing xenografts of two different murine tumors were given daily intraperitoneal injections of tyroservatide or saline as controls, after tumor implantation. The inhibition of xenografts was determined by calculating the tumor volume and measuring tumor weight. Tyroservatide could significantly inhibit the growth of human lung carcinoma A549, human leukemia K562 and human melanoma A375 in nude mice (P<0.05). In addition, tyroservatide significantly inhibited the subcutaneous tumor growth of Lewis lung carcinoma and B16 melanoma (P<0.05). Tyroservatide, however, could not significantly suppress xenografts of BGC-823 and MCF-7 in nude mice (P>0.05). The results obtained indicate that tyroservatide exhibits different effects on different tumors, which will provide clinical applications guidance of tyroservatide as an anticancer drug.