Effect of CA on the proliferation of retinoblastoma and normal human corneal epithelial cells. Y79 and HCE cells were treated with 0.001, 0.01, 0.1, 0.5, 1, 5, 10, 25, 50 and 100 μM concentration of CA for 24 h. The percentage of viable cells with treatment was calculated in comparison with untreated control cells. The number of cells in the control was taken as 100%. Data was represented as mean ± S.E.M of three independent experiments. *P < 0.01 vs untreated control was considered to indicate significance.