FIGURE 3.

Effect of IFNγ on the proportions of HSC-2 and Ca9–22 cells at different stages of the cell cycle. A, asynchronously growing HSC-2 or Ca9–22 cells were treated with or without IFNγ (10 ng/ml) for the indicated time periods. The cells were then harvested, and flow cytometric analysis for DNA content was performed, as described under “Experimental Procedures.” Flow cytometric data were analyzed using WinCycle software to determine the proportion of cells in each stage of the cell cycle. Data shown are the means ± S.E. of 8–11 independent experiments. Asterisks denote a statistically significant difference from untreated (UT) cultures (*, p < 0.05, Student's t test). B, inhibition of DNA synthesis in IFNγ-treated HSC-2 cells. The cells were cultured in the presence or absence of IFNγ (10 ng/ml) for the indicated time periods, and the rate of DNA synthesis was determined by pulse labeling with [³H]thymidine for the last hour of incubation. Each column and bar represents the mean ± S.E. of three independent experiments.