Fluorouracil (5-FU) and Cytarabine (Ara-C) Inhibition of Corneal Epithelial Cell and Conjunctival Fibroblast Proliferation

We evaluated the antiproliferative properties of fluorouracil (5-FU) and cytarabine (ara-C) in a tissue culture model of rabbit corneal epithelial cells and conjunctival fibroblasts. Cells were treated with fluorouracil or cytarabine for five days. Corneal epithelial cell proliferation was inhibited to 50% of control proliferation by 0.6 mg/L of fluorouracil or 30 μg/L of cytarabine. Proliferation of conjunctival fibroblasts was inhibited to 50% of control by 0.5 mg/L of fluorouracil or 50 μg/L of cytarabine. The antiproliferative effect of 10 mg/L of fluorouracil was not blocked by thymidine. The inhibition of proliferation produced by 100 or 1,000 μg/L of cytarabine was blocked by 2'-deoxycytidine at concentrations of 10^-5M and 10^-4M, respectively. The antiproliferative effects of fluorouracil and cytarabine appear similar for both cell types. Blockage of cytarabine-related ocular toxic effects may be possible with 2'-deoxycytidine.