Curcumin inhibits the growth of AGS human gastric carcinoma cells in vitro and shows synergism with 5-fluorouracil.

The inhibitory effect of curcumin and its synergism with 5-fluorouracil (5-FU) on the growth of the AGS human gastric carcinoma cell line was examined. Cell cycle analysis was used to elucidate the mechanisms for the inhibition by curcumin. Curcumin significantly inhibited the growth of AGS cells in a dose- and time-dependent manner (P <.05). Curcumin caused a 34% decrease in AGS proliferation at 5 micromol/L, 51% at 10 micromol/L, and 92% at 25 micromol/L after 4 days of treatment. When curcumin (10 micromol/L) was removed after a 24-hour exposure, the growth pattern of curcumin-treated AGS cells was similar to that of control cells, suggesting reversibility of curcumin on the growth of AGS cells. Combining curcumin with 5-FU significantly increased growth inhibition of AGS cells compared with either curcumin or 5-FU alone (P <.05), suggesting synergistic actions of the two drugs. After 4 days of treatment with 10 micromol/L of curcumin, the G2/M phase fraction of cells was 60.5% compared with 22.0% of the control group, suggesting a G2/M block by curcumin treatment. Because the curcumin concentrations (5 micromol/L) used in our study were similar to steady-state concentrations (1.77 +/- 1.87 micromol/L) in human serum of subjects receiving chronic administration of a commonly recommended dose (8 g/day), curcumin may be useful for the treatment of gastric carcinoma, especially in conjunction with 5-FU.