Methods: Cell viability was examined by MTT assay, whereas cell motility was measured by invasive, migration and would healing assays. Assessment of mRNA levels, using reverse transcriptase polymerase chain reaction (PCR), real-time PCR, and promoter assays confirmed the inhibitory effects of Tricetin on matrix metalloproteinase-9 (MMP-9) expression in oral cancer cells.
Results: The present study demonstrates that Tricetin at a range of concentrations (0~20 μM), concentration-dependently inhibited migration/invasion capacities of SCC-9 (p<0.001), without cytotoxic effects. Zymography and Western blotting analyses revealed that Tricetin inhibited MMP-9 enzyme activity, and protein expression. Data also showed Tricetin could inhibit phosphorylation of c-Jun N-terminal kinase 1 and 2 (JNK1/2) involved in the down-regulating protein expressions and transcriptions of MMP-9.
Conclusions: Tricetin inhibits MMP-9 expression and oral cancer cell metastasis and, thus, has potential use as a chemopreventive agent. Its inhibitory effects are associated with downregulation of JNK 1/2 signals pathways.