To investigate the effects of two antimetabolites, mitomycin C (MMC) and 5-fluorouracil (5-FU), on proliferation of cultured human nasal mucosa fibroblasts.

Human nasal mucosa fibroblasts were primarily cultured, and exposed to various concentrations of MMC and 5-FU for 5 minutes. Control fibroblasts were exposed to only DMEM media without the drugs. Effect of drugs on cell morphology was observed by phase-contrast microscopy. Cell viability and apoptosis were measured using MTT [3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyl-tetrazolium bromide] assay and Acridine orange/Hoechst (AO/HO) staining, respectively.

In both experimental groups exposed to MMC and 5-FU, fibroblasts maintained standard spindle shape. The MTT assay showed that both MMC and 5-FU inhibited fibroblast proliferation in a dose dependent manner. AO/HO staining showed apoptotic cells in both experimental groups.

Both MMC and 5-FU have an antiproliferative effect on fibroblasts in vitro at least through induction of apoptosis. Therefore, adjuvant use of either MMC or 5-FU during endonasal dacryocystorhinostomy may improve the clinical outcome by inhibiting proliferation of the nasal mucosa.