The incorporation time periods were 1 h and 3 h in NGM cells and 1 h in HT144. A time interval of 3 hours was tested in the NGM cells because of their slower proliferation rate (data obtained by growth curves). In

addition, the BrdU incorporation experiments showed a significant reduction in the percentages of cells in S phase in both cell lines after treatment with 3.2 mM cinnamic acid (Figure 1). However, we found no differences between the periods of incorporation (Figure 1). VX-770 nmr The reduction in the percentage of cells in S phase was more significant in HT-144 cells than in NGM cells. In these cells, the BrdU incorporation index decreased from 22% in the control group to 0% in the group treated with 3.2 mM cinnamic acid (Figure 1). Figure 1 BrdU incorporation in NGM and HT-144 cells treated with cinnamic acid. The cells incorporate BrdU

for different periods after 48 hours of treatment with two concentrations of cinnamic acid. We observed significative effects of cinnamic acid on DNA synthesis only in cells treated with 3.2 mM of the drug. Bars = standard error. We also used a 0.05 mM cinnamic acid concentration along the study; however we did not find changes in comparison to the control group. Cell death detection The interference of cinnamic acid in the cell cycle may result in cell death. To confirm this hypothesis, the cells were labeled with SRT2104 price M30. The HT-144 cell line showed an increased frequency in labeled cells after 24 h of treatment with both concentrations of the drug and this increase was time-dependent (Table 2). Table 2 Frequency of HT-144 cells positive for

M30 (%) after treatment with cinnamic acid Time of treatment Control 0.4 mM 3.2 mM 24 hours 0.80 ± 0.07 5.00 ± 0.09a 7.30 ± 1.02a 48 hours 1.20 ± 0.06 12.30 ± 1.95a 27.03 ± 2.36a Results are showed as Mean ± SD. a Significantly different (p≤0.05) vs control group. The activated-caspase 9 assay confirmed the data obtained from the M30 labeling of HT-144 cells (Figure 2). Because nearly we could not analyze the cell death in the NGM cell line using M30 labeling, we performed the active-caspase 9 assay in NGM cells (Figure 3) to compare the effects of cinnamic acid in both cell lines. Cells exposed to ultraviolet radiation for 1 minute were used as a positive control. This experiment verified that both cell lines could functionally activate the caspase cascade during the cell death process. Figure 2 Activated-caspase 9 assay to cell death analysis on HT-144 cells. The activated-caspase 9 kit (GE Healthcare) was used to detect different selleck compound stages of cell death. The cells were treated at 0.4 or 3.2 mM cinnamic acid for 6 (A, B, C), 12 (D, E,F) and 24 hours (G, H, I). We can observe increased frequency of apoptotic cells after 24 h of treatment at 3.2 mM cinnamic acid. Figure 3 Activated-caspase 9 assay to cell death analysis on NGM cells. The activated-caspase 9 kit (GE Healthcare) was used to detect different stages of cell death.