Evaluation for Antitumor-promoting Activity of Meyerin and 7-Methoxy-5-prenyloxycoumarin in Meyer Lemon

Abstract

We previously reported on meyerin (trans-4-hydroxycinnamic acid derivative) and 7-methoxy-5-prenyloxycoumarin, which are abundantly found in Meyer lemon (Citrus meyeri) relative to other citrus fruits. In the present study, the antitumor-promoting activities of these compounds were examined using the in vitro Epstein-Barr virus early antigen (EBV-EA) activation test and the in vivo two-stage mouse skin carcinogenesis test. 7-Methoxy-5-prenyloxycoumarin was suggested to have inhibitory activity on tumor promotion in the EBV-EA test, whereas meyerin exhibited weak activity. Furthermore, 7-methoxy-5-prenyloxycoumarin significantly inhibited mouse skin tumor promotion relative to control in the two-stage carcinogenesis test. These results indicate that 7-methoxy-5-prenyloxycoumarin has antitumor-promoting activity in vitro and in vivo.