Figure 1.

Antiproliferative effect of caffeic acid against colon cancer cells growth in vitro. (a) HCT 15 cells grown in 96-well plates were treated with various concentrations of caffeic acid diluted in the RPMI media for 48 h. The mean of the percentage cell viability (% of untreated HCT 15 cells) along with their standard error is indicated. (b) After various incubation periods of caffeic acid treatment, colonies formed were stained with 0.5% crystal violet and counted, and percentage of survival was calculated. Data reported as the mean ± SE from three different observations. Means are significant at 24 and 48 h (P < 0.05).