Inhibitory effects of N-acetylcysteine on invasion and MMP-9 production ofT24 human bladder cancer cells

Background: MMPs play a crucial role in the process of cancer invasion and metastasis. Methods: The influence of NAC on invasion and MMP-9 production of human bladder cancel. cell line T24 was investigated using an in vitro i nvasion assay, gelatin zymography, Western and Northern blot analyses and R T-PCR assays. Results: TPA increased the number of invading T24 cells throu gh reconstituted basement membrane more than 10-fold compared to basal cond ition. NAC inhibited TPA-enhanced invasion dose-dependently. TPA increased the MMP-9 production by T24 cells without altering expression of TIMP-1 gen e, while NAC suppressed TPA-enhanced production of MMP-9. Neither TPA nor N AC altered TIMP-1 mRNA level in T24 cells, In vitro experiments demonstrate d that MMP-9 was directly inhibited by NAC but was not influenced by TPA. C onclusion: NAC limits invasion of T24 human bladder cancer cells by inhibit ing the MMP-9 production in addition to a direct inhibition of MMP-9 activi ty.