ABSTRACT
Objective: To investigate the effects and mechanism of gochnatiolide A from Ainsliaea in anti-prostate cancer. Methods: The activities of gochnatiolide A on the proliferation of DU145 cells were tested by CCK-8 and colony formation experiments. Apoptosis morphological changes of cells were observed by DAPI staining. The apoptosis and cell cycle were evaluated by flow cytometry. The expressions of cleaved Poly ADP ribose polymerase (cleaved-PARP), cleaved cystein-containing aspartate specific protease 9 (cleaved Caspase-9), tumor suppressor protein (p53), b cell lymphoma-2 (Bcl-2), transcription factors-κB p65 (NF-κB p65) and IκB kinase α, β (IKKα, IKKβ) proteins in DU145 cells were investigated by Western blotting. Results: The natural product gochnatiolide A significantly inhibited the proliferation of prostate cancer DU145 cells, with IC50 values of 4.15, 2.80 and 1.74 μmol/L at 12 h, 24 h, and 48 h, respectively. Meanwhile, gochnatiolide A promoted DU145 cells apoptosis and induced cell cycle arrest at G2 and S phases in a concentration dependent manner. In addition, gochnatiolide A also up-regulated apoptosis proteins cleaved-PARP, cleaved Caspase-9 and p53 proteins, and down-regulated Bcl-2 protein. Comparing the control group, the expression of NF-κB p65, IKKα and IKKβ proteins in the NF-κB pathway were decreased after treatment with gochnatiolide A. Conclusion: The natural product gochnatiolide A remarkably inhibited the proliferation and promoted apoptosis in DU145 cells, and the possible mechanism was related to the inhibition of NF-κB pathway.
ABSTRACT
Objective To observe the influence of sirtinol,a silent information regulator 1(SIRT1)inhibitor,in the cell proliferation, cell cycle progression and the expression levels of positive regulator proteins of the cell cycle including Cyclin D1,CDK4 and pRb in prostate cancer DU145 cells,and to explore the possible mechanism of SIRT1 in occurrence of prostagte cancer.Methods The DU145 cells at logarithmic growth phase were cultured in vitro and divided into control group(DMSO)and different doses (10,25,50μmol·L-1 )of sirtinol groups.The inhibitory rate of growth of DU145 cells was detected with MTT method,the SIRT1 mRNA and protein expression levels were determined by RT-PCR and Western blotting method, and the cell cycle was measured by flow cytometry.The Cyclin D1,CDK4 and pRb protein expression levels were examined by Western blotting method. Results Compared with control group, the inhibitory rates of growth of the DU145 cells in different doses of sirtinol groups were increased markedly in a dose-dependent manner(P0.05).Conclusion SIRT1 inhibition by sirtinol can inhibit the cell growth of prostate cancer DU145 cells in a dose-dependent manner and arrest the cell cycle progression,and its mechanism may be related to decreasing the CyclinD1 and pRb protein expressions.