MMP1 and nasopharyngeal carcinoma: To test the hypothesis that MMP-1 and TIMP-1were both regulated by gallic acid and contributed to the inhibited matrix invasion of NPC-BM1 cells, we examined the mRNA and protein expression of TIMP-1 in NPC-BM1 cells after gallic acid treatment for 24 h by RT/real-time PCR and western blot, respectively.