Grape Proanthocyanidins Induce Apoptosis by Loss of Mitochondrial Membrane Potential of Human Non-Small Cell Lung Cancer Cells In Vitro and In Vivo

Abstract

Lung cancer remains the leading cause of cancer-related deaths worldwide, and non-small cell lung cancer (NSCLC) represents approximately 80% of total lung cancer cases. The use of non-toxic dietary phytochemicals can be considered as a chemotherapeutic strategy for the management of the NSCLC. Here, we report that grape seed proanthocyanidins (GSPs) induce apoptosis of NSCLC cells, A549 and H1299, in vitro which is mediated through increased expression of pro-apoptotic protein Bax, decreased expression of anti-apoptotic proteins Bcl2 and Bcl-xl, disruption of mitochondrial membrane potential, and activation of caspases 9, 3 and poly (ADP-ribose) polymerase (PARP). Pre-treatment of A549 and H1299 cells with the caspase-3 inhibitor (z-DEVD-fmk) significantly blocked the GSPs-induced apoptosis of these cells confirmed that GSPs-induced apoptosis is mediated through activation of caspases-3. Treatments of A549 and H1299 cells with GSPs resulted in an increase in G1 arrest. G0/G1 phase of the cell cycle is known to be controlled by cyclin dependent kinases (Cdk), cyclin-dependent kinase inhibitors (Cdki) and cyclins. Our western blot analyses showed that GSPs-induced G1 cell cycle arrest was mediated through the increased expression of Cdki proteins (Cip1/p21 and Kip1/p27), and a simultaneous decrease in the levels of Cdk2, Cdk4, Cdk6 and cyclins. Further, administration of 50, 100 or 200 mg GSPs/kg body weight of mice by oral gavage (5 d/week) markedly inhibited the growth of s.c. A549 and H1299 lung tumor xenografts in athymic nude mice, which was associated with the induction of apoptotic cell death, increased expression of Bax, reduced expression of anti-apoptotic proteins and activation of caspase-3 in tumor xenograft cells. Based on the data obtained in animal study, human equivalent dose of GSPs was calculated, which seems affordable and attainable. Together, these results suggest that GSPs may represent a potential therapeutic agent for the non-small cell lung cancer.

Inhibition of class I histone deacetylases in non-small cell lung cancer by honokiol leads to suppression of cancer cell growth and induction of cell death in vitro and in vivo

“…These cell lines were maintained and cultured as detailed previously. 43 Our in vivo study provides further evidence that administration of honokiol by gavage inhibits the growth of both A549 and H1299 tumor xenografts without any apparent sign of toxicity in the mice. Furthermore, consistent with the findings in cell culture model, the tumor cells from honokiol-treated mice were undergoing apoptotic cell death as indicated by the TUNELpositive cells as well as increases in the levels of pro-apoptotic protein Bax and cleaved caspase-3.…”

Prodelphinidins isolated from Chinese bayberry leaves induces apoptosis via the p53-dependent signaling pathways in OVCAR-3 human ovarian cancer cells

“…A number of studies have demonstrated that grape seed procyanidins induce apoptosis in cancer cells through the intrinsic and extrinsic pathways by downregulating antiapoptotic proteins and upregulating several proapoptotic factors. This eventually leads to the activation of caspases-9 and -3 (19)(20)(21), which is in accordance with the results of the present study. The present study also showed that p53 is associated with OPA-and PPA-induced apoptosis (Fig.…”

Fructus phyllanthi tannin fraction induces apoptosis and inhibits migration and invasion of human lung squamous carcinoma cells in vitro via MAPK/MMP pathways

“…The induction of apoptosis is considered to be one potential mechanism of cancer development inhibition, and many types of tannin agents, such as proanthocyanidins [18] and casuarinin [19] , have been shown to act through the induction of apoptosis to inhibit the lung cancer process. Apoptosis may represent a protective mechanism against neoplastic development via the removal of genetically damaged cells or cells that have improperly proliferated.…”