Effects of chemotherapy on invasion and metastasis of oral cavity cancer in mice

Background. Using an orthotopic implantation model in which oral cancer inv asion and metastasis can be reproduced, we investigated the inhibitory effe cts of anticancer agents on invasion and metastasis. Methods, A highly invasive and metastatic human oral squamous cell carcinom a cell line, OSC-19, was implanted into the oral floor of nude mice, and ci splatin or peplomycin was administered to the mice 7 or 14 days after impla ntation. The effects of each anticancer drug and different administration t imings on cancer invasion and metastasis were investigated. Results. Tumor size and the ratio of proliferating cell nuclear antigen-pos itive cells was significantly reduced. In the control group, the tumors sho wed grade 4C mode of invasion, whereas in the groups treated with anticance r drugs, grade 3 was observed in 77.3% of the mice, with an inhibitory effe ct on tumor invasion being observed. The rate of metastasis in the cervical lymph node was significantly decreased in the groups treated with the cisp latin or peplomycin on day 7 after implantation, The tumor stage progressio n in the metastatic lymph nodes was also inhibited. Conclusions. Chemotherapy is effective not only for tumor diminution but al so for Inhibiting invasion and metastasis. In light of these effects, admin istration of anticancer drugs may be clinically useful in this regard. (C) 2001 John Wiley & Sons, Inc.