Abstract: Abstract: Objective To investigate the effect and possible mechanism of osthole on proliferation and apoptosis of human lung cancer H1299 cells, and to provide theoretical reference for its clinic treatment. Methods The H1299 cells were incubated with various concentrations of osthole (0, 20, 40, 60, 80, 100, 120, 140 and 160 μmol/L) for 48 h. The cell proliferation was examined by MTT assay to determine the dosages in subsequent experiments. With the different concentrations of osthole (0, 40, 80, 120, and 160 μmol/L) for 48 h, the cell apoptosis rate was measured by flow cytometry. The B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), nuclear factor kappa-B (NF-κB) and phosphorylated NF-κB (pNF - κB) levels were determined by Western-blot assay. Results In comparison with the control group, osthole with
concentrations of 40, 60, 80, 100, 120, 140 and 160 μmol/L could obviously inhibit the proliferation in H1299 cells (P＜
0.05). Osthole (80, 120 and 160 μmol/L) accelerated the cellular apoptosis, decreased the expressions of Bcl-2 and pNF-κB
and increased the expression of Bax (P＜0.05), while osthole showed no significant effect on the expression of NF-κB (P＞
0.05). Conclusion Osthole can inhibit H1299 cell proliferation and accelerate the cell apoptosis, which might be
associated with the activation of the apoptotic factor Bax, the suppression of the expression of the anti-apoptosis factor Bcl-2
and the down-regulation of pNF-κB expression.

Key words: lung neoplasms, Osthole, apoptosis, NF-κB