• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.7
• /
• pp.3073-3076
• /
• 2012

Terpinen-4-ol is a terpene found in the rhizome of Plai (Zingiber montanum (Koenig) Link ex Dietr.). In this study apoptogenic activity and mechanisms of cell death induced by terpinen-4-ol were investigated in the human leukemic MOLT-4 cell line. Terpinen-4-ol exhibited cytotoxicity in MOLT-4 cells, with characteristic morphological features of apoptosis by Wright's staining. The mode of cell death was confirmed to be apoptosis by flow cytometric analysis after staining with annexin V-FITC and propidium iodide. A sub-G1 peak in DNA histograms of cell cycle assays was observed. Terpinen-4-ol induced-MOLT-4 cell apoptosis mediated through an intrinsic pathway involving the loss of mitochondrial transmembrane potential (MTP) and release of cytochrome c into the cytosol. In addition, terpinen-4-ol also induced apoptosis via an extrinsic pathway by caspase-8 activation resulting in the cleavage of cytosolic Bid. Truncated-Bid (tBid) translocated to mitochondria and activated the mitochondrial pathway in conjunction with down-regulation of Bcl-2 protein expression. Caspase-3 activity also increased. In conclusion, terpinen-4-ol can induce human leukemic MOLT-4 cell apoptosis via both intrinsic and extrinsic pathways.

• Journal of Life Science
• /
• v.27 no.11
• /
• pp.1340-1348
• /
• 2017

Sanguinarine is a benzophenanthridine alkaloid derived from the roots of Sanguinaria canadensis L., which is used for the purpose of treating various diseases. Although studies of anticancer activities have been performed using various cancer cell lines, the phenomenon of inducing apoptosis in cancer cells by using sanguinarine requires more research. Therefore, this study investigated the anti-cancer activities and related mechanisms of sanguinarine used with Hep3B human hepatocellular carcinoma cells in terms of the regulation of apoptosis. Sanguinarine inhibited the proliferation of Hep3B cells in a concentration-dependent manner, which was associated with the induction of apoptosis. Sanguinarine also increased the activity of caspase-3, which is a typical effector caspase, and the activities of caspase-8 and caspase-9, which are key when initiating extrinsic and intrinsic apoptosis pathways, respectively. In addition, sanguinarine increased the expression of death receptor-related genes and pro-apoptotic BAX, which belongs to the Bcl-2 family, while suppressing the expression of anti-apoptotic Bcl-2. Sanguinarine promoted the truncation of Bid and enhanced the release of cytochrome c from the mitochondria to the cytoplasm due to a loss of mitochondrial membrane potential. Furthermore, the reduction of a survival rate that was induced by sanguinarine and the induction of apoptosis disappeared with the inhibition of artificial caspase activity. Therefore, the results of the study indicated that sanguinarine-induced apoptosis in Hep3B cells involves both extrinsic and intrinsic pathways; such apoptosis is a caspase-dependent phenomenon.

• The Korean Journal of Physiology and Pharmacology
• /
• v.14 no.6
• /
• pp.407-412
• /
• 2010

3-Deazaadenosine (DZA), a potent inhibitor of S-adenosylhomocysteine hydrolase, was previously proposed to induce intrinsic apoptosis in human leukemic cells. In the present study, we analyzed the mechanism underlying the DZA-induced intrinsic apoptotic pathway. DZA activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an accumulation of hypo-diploidic cells, the processing of multiple procaspases and an inhibitory effect of z-VAD-Fmk on this cell death. During DZA-induced apoptosis, cytochrome c (cyt c) was released into the cytosol. This was neither prevented by z-VAD-Fmk and nor was it associated with the dissipation of mitochondrial membrane potential (${\Delta}{\Psi}_m$). Prior to the release of cyt c, BAX was translocated from the cytosol to mitochondria and underwent oligomerization. Finally, the overexpression of BCL-XL protected HL-60 cells from apoptosis by blocking both the cyt c release and BAX oligomerization. Collectively, these findings suggest that DZA may activate intrinsic apoptosis by stimulating BAX activation and thereby the release of cyt c.

• Molecules and Cells
• /
• v.27 no.5
• /
• pp.533-538
• /
• 2009

Heat shock protein 27 (Hsp27) is a molecular chaperone protein which regulates cell apoptosis by interacting directly with the caspase activation components in the apoptotic pathways. With the assistance of the Tat protein transduction domain we directly delivered the Hsp27 into the myocardial cell line, H9c2 and demonstrate that this protein can reverse hypoxia-induced apoptosis of cells. In order to characterize the contribution of Hsp27 in blocking the two major apoptotic pathways operational within cells, we exposed H9c2 cells to staurosporine and cobalt chloride, agents that induce mitochondria-dependent (intrinsic) and -independent (extrinsic) pathways of apoptosis in cells respectively. The Tat-Hsp27 fusion protein showed a greater propensity to inhibit the effect induced by the cobalt chloride treatment. These data suggest that the Hsp27 predominantly exerts its protective effect by interfering with the components of the extrinsic pathway of apoptosis.

• Nutrition Research and Practice
• /
• v.8 no.2
• /
• pp.132-137
• /
• 2014

BACKGROUND/OBJECTIVES: In this study, the apoptogenic activity and mechanisms of cell death induced by hexane extract of aged black garlic (HEABG) were investigated in human leukemic U937 cells. MATERIALS/METHODS: Cytotoxicity was evaluated by MTT (3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide) assay. Apoptosis was detected using 4,6-diamidino-2-phenyllindile (DAPI) staining, agarose gel electrophoresis and flow cytometry. The protein levels were determined by Western blot analysis. Caspase activity was measured using a colorimetric assay. RESULTS: Exposure to HEABG was found to result in a concentration- and time-dependent growth inhibition by induction of apoptosis, which was associated with an up-regulation of death receptor 4 and Fas legend, and an increase in the ratio of Bax/Bcl-2 protein expression. Apoptosis-inducing concentrations of HEABG induced the activation of caspase-9, an initiator caspase of the mitochodrial mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly(ADP-ribose)-polymerase. HEABG also induced apoptosis via a death receptor mediated extrinsic pathway by caspase-8 activation, resulting in the truncation of Bid, and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. However, pre-treatment of U937 cells with the caspase-3 inhibitor, z-DEVD-fmk, significantly blocked the HEABG-induced apoptosis of these cells, and increased the survival rate of HEABG-treated cells, confirming that HEABG-induced apoptosis is mediated through activation of caspase cascade. CONCLUSIONS: Based on the overall results, we suggest that HEABG reduces leukemic cell growth by inducing caspase-dependent apoptosis through both intrinsic and extrinsic pathways, implying its potential therapeutic value in the treatment of leukemia.

• Journal of Life Science
• /
• v.25 no.9
• /
• pp.984-992
• /
• 2015

Sanguinarine is a benzophenanthridine alkaloid originally isolated from the roots of Sanguinaria canadensis. It has multiple biological activities (e.g., antioxidant and antiproliferative) and immune-enhancing potential. In this study, we explored the proapoptotic properties and modes of action of sanguinarine in human hepatocellular carcinoma HepG2 cells. Our results revealed that sanguinarine inhibited HepG2 cell growth and induced apoptosis in a dose-dependent manner. The induction of apoptosis by sanguinarine was associated with the up-regulation of Fas and Bax, the release of cytochrome c from the mitochondria to the cytosol, and the loss of the mitochondrial membrane potential. In addition, sanguinarine activated caspase-9 and -8, initiator caspases of the intrinsic and death extrinsic pathways, respectively, and caspase-3, accompanied by proteolytic degradation of poly (ADP-ribose) polymerase. Sanguinarine also triggered the generation of reactive oxygen species (ROS). The elimination of ROS by N-acetylcysteine reversed sanguinarine-induced apoptosis. Furthermore, sanguinarine induced the dephosphorylation of Akt and the phosphorylation of mitogen-activated protein kinases, including extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), and p38. The growth inhibition was enhanced by the combined treatment of sanguinarine with a phosphatidylinositol 3'-kinase (PI3K) inhibitor and an ERK inhibitor but not JNK and p38 inhibitors. Overall, our data indicate that the proapoptotic effects of sanguinarine in HepG2 cells depend on ROS production and the activation of both intrinsic and extrinsic signaling pathways, which is mediated by blocking PI3K/Akt and activating the ERK pathway. Thus, our data suggest that sanguinarine may be a natural compound with potential for use as an antitumor agent in liver cancer.

• The Korean Journal of Food And Nutrition
• /
• v.35 no.3
• /
• pp.178-184
• /
• 2022

The objective of the present study was to investigate the molecular mechanisms involved in the activity of [10]-gingerol using A2058 human melanoma cells. [10]-Gingerol inhibited the proliferation of A2058 cells by 50% at a concentration of 52 μM. Such inhibition was dose-dependent accompanied by morphological change indicative of apoptosis. Furthermore, flow cytometric analysis by Annexin V and PI double staining showed that [10]-gingerol increased the extent of apoptosis. Analysis of the mechanism of these events indicated that [10]-gingerol increased the ratio of Bax to Bcl-2, resulting in the activation of caspase-9, caspase-3, and poly-ADP-ribose polymerase in a dose-dependent manner.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.1
• /
• pp.237-242
• /
• 2013

Cervical cancer is the second most common cause of cancer in women and has a high mortality rate. Cisplatin, an antitumor agent, is generally used for its treatment. However, the administration of cisplatin is associated with side effects and intrinsic resistance. Morinda citrifolia (Noni), a natural plant product, has been shown to have anti-cancer properties. In this study, we used Noni, cisplatin, and the two in combination to study their cytotoxic and apoptosis-inducing effects in cervical cancer HeLa and SiHa cell lines. We demonstrate here, that Noni/Cisplatin by themselves and their combination were able to induce apoptosis in both these cell lines. Cisplatin showed slightly higher cell killing as compared to Noni and their combination showed additive effects. The observed apoptosis appeared to be mediated particularly through the up-regulation of p53 and pro-apoptotic Bax proteins, as well as down-regulation of the anti-apoptotic Bcl-2, Bcl-$X_L$ proteins and survivin. Augmentation in the activity of caspase-9 and -3 was also observed, suggesting the involvement of the intrinsic mitochondrial pathway of apoptosis for both Noni and Cisplatin in HeLa and SiHa cell lines.

• Molecules and Cells
• /
• v.39 no.2
• /
• pp.119-128
• /
• 2016

Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-$3{\beta}$ activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.

• Journal of Acupuncture Research
• /
• v.31 no.2
• /
• pp.87-98
• /
• 2014

Objectives : We investigated whether snake venom toxin(SVT) from Vipera lebetina turanica sensitizes HT29 human epithelial colorectal cancer cells to tumor necrosis factor(TNF)-related apoptosis-inducing ligand(TRAIL) induced apoptosis in cancer cells. Methods : Cell viability assay was used to assess the inhibitory effect of TRAIL on cell growth of HT29 human colorectal cancer cells. And 6-diamidino-2-phenylindole(DAPI), terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay(TUNEL) staining assay were used to evaluate cell-apoptosis. Western blot analysis were conducted to observe apoptosis related proteins and death receptor. To assess whether the synergized inhibitory effect of SVT and TRAIL on reactive oxygen species(ROS) generation was reversed by strong anti-oxidative agent. Results : SVT with TRAIL inhibited HT29 cell growth different from TRAIL alone. Consistent with cell growth inhibition, the expression of TRAIL receptors; Expression of death receptor(DR)4 and DR5 was significantly increased and intrinsic pro-apoptotic cleaved caspase-3, -9 was subsequently increased together with increase of Bax/Bcl-2 ratio and extrinsic pro-apototic caspase-8 was also activated. In addition, the expression of anti-apoptotic survival proteins, a marker of TRAIL resistance(eg, cFLIP, survivin, X-linked inhibitor of apoptosis protein(XIAP) and Bcl-2) was suppressed by the combination treatment of SVT and TRAIL. Pretreatment with the ROS scavenger N-acetylcysteine abolished the SVT and TRAIL-induced upregulation of DR4 and DR5 expression and expression of the intrinsic pro-apoptotic caspase-3 and-9. Conclusion : The collective results suggest that SVT facilitates TRAIL-induced apoptosis in $HT_{29}$ human epithelial colorectal cancer cells through up-regulation of the TRAIL receptors; DR4 and DR5 and consecutive induction of bilateral apoptosis via regulating apoptosis related proteins.