Mao-to, a Kampo medicine, inhibits motility of highly metastatic osteosarcoma cells

Abstract

We used a cancer cell motility assay system for the mouse sera (MS) obtained from mice orally given Kampo medicines to find their ability to inhibit metastasis. The motility of the highly metastatic osteosarcoma cell, FBJ-LL, was significantly reduced by MS obtained from mice given Mao-to (TJ-27), but not influenced by those obtained from mice given either Juzen-taiho-to (TJ-48) or Hochu-ekki-to (TJ-41). A reduction in motility was also caused by MS with the addition of Mao-to (TJ-27), suggesting that the reduction can be caused by original compound(s) in Mao-to (TJ-27). Mao-to (TJ-27) caused 80 % reduction in FBJ-LL cell motility at a concentration of 100 μg/ml without cytotoxicity, and completely suppressed proliferation of FBJ-LL cells at 1000 μg/ml. Accordingly, Mao-to (TJ-27) may be an inhibitor of metastasis at a low concentration. Mao-to (OMRC-K) inhibited the motility as well as Mao-to (TJ-27). Thus Mao-to generally has an inhibitory effect on the motility. Ephedrae herba and Cinnamomi cortex, which are the ingredients of Mao-to, inhibited cell motility, indicating that these herbs play a critical role in inhibition of cancer cell motility. These results raise the possibility that Mao-to is a candidate for a novel inhibitor of metastasis.