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Aim To study the inhibitory effect of attenuated salmonella SGN1, overexpressing methioninase, on nasopharyngeal carcinoma (NPC) and the underlying mechanism. Methods The cell proliferation, cell cycle, cell apoptosis, clony formation and migration a-bility of 5-8F, HNE-2, CNE-2 cells were measured u-sing flow cytometry assay, clone formation assay, and wound assay after the methionine restriction treatment. 5-8F, HNE-2, CNE-2 cells were infected with SGN1 at the multiplicity of infection (MOI) of 1: 100 for 5 hours, followed with the measurement of cell growth. A xenograft model was constructed by subcutaneous injection of 5-8F cells in mice to observe the inhibitory effect of SGN1 on nasopharyngeal carcinoma. Results Compared with the control group, methionine restriction significantly inhibited the proliferation, migration ability, and clone formation of nasopharyngeal carcinoma cells and blocked the G
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Objective To investigate the apoptosis-inducing effect and anti-proliferative effect of epigallocatechin-3-gallate (EGCG) on human pancreatic cancer cell SW1990 in vitro. Methods The effect of proliferation was evaluated by MTT after the SW1990 cells in vitro were incubated with different concentrations of EGCG (6.25, 12.5, 25, 50, 100 μg/ml). The apoptosis-inducing effect was determined by flow cytometry after the cells were treated with 25 μg/ml of EGCG. The cell cycle of SW1990 cells was detected by flow cytometry after the cells incubated with different concentrations of EGCG (0, 10, 20, 30, 40, 50 μg/ml).Results After SW1990 cell were treated with different concentrations of EGCG (0, 25, 50 μg/ml), the values of A492 were 0.46 ±0.04,0.42 ±0.04,0.27 ±0.03 at 24 h; 0.48 ±0.02, 0.31 ±0.03,0.16 ±0.02at 48 h; 0.51 ±0.01,0.24 ±0.04,0. 14 ±0.04 at 72 h. EGCG inhibited the proliferation of SW1990 in a doseand time-dependant manner(P ＜0.01 ). The apoptotic rates at 24, 48, 72 h were (8.33 ± 1.15 )%, (19.77 ±0.81 )%, (29.17 ± 0.75 )% in the EGCG treatment group; while the corresponding values were (2.77 ±0.45 ) %, (3.20 ± 0.26 ) %, (3.67 ± 0.35 ) % in the control group; and the difference was statistically significant (P ＜0.01 ). After 0, 20, 50 μg/ml of EGCG treatment for 24 h, the percentages of SW1990 cellsin G0/G1 stage were (57.59 ±0.97)%, (62.99 ± 1.91 )%, (68.87 ± 1.88)%, and the percentages of SW1990 cells in G0/G1 stage increased with the increase of concentrations of EGCG, while the percentages of SW1990 cells in G2/M stage decreased with the increase of concentrations of EGCG (P ＜0.01 ). Conclusions EGCG can significantly inhibit the proliferation of SW1990 cells. The mechanism may be related to the apoptosis-inducing effect and the regulation of the cell cycle of the SW1990 cells.