Serum Immune Marker Profile in Colorectal Carcinoma

S77is to evaluate, in vitro and in vivo, the cytotoxic effect of AA in two human colorectal adenocarcinoma cell lines (WiDr and C2BBe1).Methods: WiDr and C2BBe1 were cultured in Dulbecco's Modified Eagle's Medium supplemented with 10% fetal calf serum.Cells were incubated with different concentrations of AA.The half maximal inhibitory concentration (IC50) was calculated after 24, 48, 72 and 96 hours by the sulphorhodamine B (SRB) assay.In order to evaluate cell survival, clonogenic assays were performed.At tenth day, the number of colonies was counted, being the plate efficiency and the survival factor determined.In order to verify in vivo the evolution of tumor growth after the daily injection of AA, WiDr cells were inoculated on the back of Balb/c nu/nu mice and, during several days, the body weight and tumor size of mice were monitored.AA was not administered to control animals.Results: Both WiDr and C2BBe1 results obtained with SRB suggest that AA induces a decrease in cell proliferation in a dose-dependent way.It was also verified that as the resting time increases, the IC50 of AA decreases in both cell lines.The clonogenic assays revealed that, as the concentration of AA increases, the survival factor decreases.This behaviour was observed in both cell lines, being more evident in WiDr cells (with 0.5 mM the reduction factor is 44.88% and with 2, 3 and 5 mM is above 80%).The in vivo studies suggest that AA administered daily at 150 mg/kg inhibits tumor growth since there are significant differences between the two groups (control and under treatment).Conclusions: AA induces an inhibitory effect on the cell lines studied since there is an anti-proliferative effect and a decrease in cell survival.Our results also indicate that AA stabilizes tumor growth.The data obtained in two different human cell lines of colorectal adenocarcinoma could contribute to the insight of anti-cancer therapies with antioxidants.