Sulforaphane inhibits oral carcinoma cell migration and invasion in vitro.

Sulforaphane is a predominant isothiocyanate in Brassica oleracea, a family of cruciferous vegetables, and is known to be inversely related to the risk of various types of human carcinomas. Studies using oral carcinoma cell lines are scarce, however, and the role of sulforaphane on oral carcinoma cell metastasis is yet to be determined. In this study, the growth inhibition of oral carcinoma cell lines by sulforaphane was determined using aqueous soluble tetrazolium salts, and the growth of various oral cancer cell lines was attenuated. The migration and invasion activities of the cells also decreased, as observed in monolayer scratch assays and transwell invasion experiments. The molecular change behind the impairment of the migration and invasion was investigated via secreted metalloprotease level detection using Multiplex protein analysis kits. At the molecular level, the secreted forms of MMP-1 and MMP-2 were down-regulated. The expressions of MMP-1 and MMP-2 did not change when a conventional tumoricidal agent paclitaxel was used. These findings indicate that sulforaphane may have therapeutic potential as an inhibitor of metastasis in oral carcinoma patients.