Purpose: To evaluate the anti-tumor activity and explore the possible mechanisms of action of
paederosidic acid isolated from
Paederia scandens
(Lour.) Merrill.
Methods: Paederosidic acid (PA) was isolated from P. scandens and identified by spectroscopic
methods. The cytotoxic effects of PA in gastric cancer cell lines (MGC-803, BGC-823, and SGC-7901
cells) were assayed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT).
Apoptosis of PA in SGC-7901 cells was evaluated by DAPI staining. To investigate the possible
mechanisms of apoptosis, the effect of PA on C-caspase-3, C-caspase-9, Bcl-2 and Bax expressions in
SGC-7901 cells were assayed by Western blot analysis.
Results: PA exerted significant inhibitory effects on MGC-803, BGC-823, and SGC-7901 cells with 50
% inhibitory concentration (IC50) values of 42.2, 43.7, and 30.5 μM, respectively, and in a
concentration-dependent manner. Subsequently, SGC-7901 cells were selected for further studies.
After treatment with PA, obvious condensation of the nucleus was observed in fluorescence
photomicrographs, which is a characteristic of apoptosis. In addition, caspase-3, caspase-9 proteins
and Bax were significantly up-regulated (p < 0.05), whereas Bcl-2 was significantly down-regulated (p <
0.05) by PA in a concentration-dependent manner.
Conclusion: PA has significant anti-tumor activity on SGC-7901 cells in vitro, and the possible
mechanism of action may be related to PA-induced apoptosis via mitochondria-mediated apoptosis
pathway.
