Effect of paclitaxel on proliferation of human Tenon fibroblast and its probably mechanism

Background The excessive growth of human Tenon fibroblasts (HTFs) is a primary cause of failure of anti-glaucomatous filtering surgery.To seek a drug of anti-fibrosis is of an important significance for improving the successful rate of anti-glaucomatous filtration surgery.Objective The goal of this study was to investigate the effect of paclitaxel on proliferation of HTFs in vitro.Methods Human Tenon tissue was obtained during the anti-glaucomatous filtering surgery.HTFs were cultivated using explant method and 3-6 generations of cells were used in the experiment.The cells were identified by immunochemistry using keratin,vimentin,fibronectin and S-100.Different concentrations (0,1 ×10-s,1 × 10-7,1 × 10-6 mol/L) of paclitaxel were added into the medium,and then the cell indexes (CI) in the various groups were detected by real-time cell electronic sensing (RT-CES) 24 hours after affection of paclitaxel.Apoptosis of the cells was examined using DAPI staining,and the proportion of the cells in different cycles were assayed by flow cytorneter 12 hours after addition of paclitaxel.The expressions of matrix metalloproteinase-1 (MMP-1) protein and mRNA were detected by ELISA and real-time PCR,respectively.Results The cells migrated from the cultivated tissue within 7 days with the fibrocyte-like shape.The cells showed the positive response for vimentin and absent response for keratin,fibronectin and S-100.The CI values were 1.093 ±0.191,0.665 ± 0.093 and 0.473 ± 0.117 in the 1 × 10-8,1 × 10-7 and 1 × 10-6 mol/L paclitaxel groups,showing significant rise in comparison with the 1.514 ±0.283 of the 0 mol/L paclitaxel group (all at P =0.000).The cell nuclei were normal in the 0 mol/L paclitaxel group,however,blue-fluorescent particles and apoptotic bodied were found in the cell nuclei after affection of paclitaxel.The proportion of G2/M phase of cells were (9.20±0.80) ％,(12.37±0.45)％ and (13.80±0.35)％ in the 1×10-8 mol/L,1×10-7 mol/L and 1×10-6 mol/L paclitaxel groups,which were higher than the (7.17±0.50) ％ in the 0 mol/L paclitaxel group (P=0.005,0.000,0.000).In addition,the relative expressing level of M MP-1 mRNA (MMP-1 mRNA/GAPDH mRNA) and the expression level of MMP-1 protein in the HTFs were significantly lower in the 1 ×10-8 mol/L,1 × 10-7 mol/L and 1 × 10-6 mol/L paclitaxel groups than those in the 0 mol/L group (all at P＜0.05).Conclusions Paclitaxel at the concentrations of 1 × 10-8 mol/L-1 × 10-6 mol/L inhibits the proliferation of HTFs in vitro by arresting the cellular mitosis and inducing cell apoptosis.These effects probably associated with down-regulation of MMP-1 expression in the HTFs. Key words: Paclitaxe/pharmacology ;  Glaucoma/surgery;  Tenon capsule/ cytology;  Fibroblast/cytology; Matrix metalloproteinase-1