• Herbal Formula Science
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• v.10 no.2
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• pp.213-223
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• 2002

The fruiting bodies of Isaria japonica have been traditionally used in Korea to treat cancer. An apoptosis-inducing compound, 4-Acetyl-12, 13-epoxyl -9-trichothecene-3, I5-diol (AETD), was isolated from the methanol extract of fruiting bodies of Isaria japonica Yasuda by bioassay -guided fractionation. The apoptosis of murine bladder cancer cell line (NBT-Ⅱ) by the compound was accessed by propidium iodide staining flow cytometric analysis, and apoptosis-inducing activity at $IC_{50}$ concentration (5 nmol／L) was further confirmed by a nuclear morphological change, a ladder pattern of DNA fragmentation, and an activation of caspase-3. These results indicate that AETD induces apoptosis of NBT-Ⅱ cells via expression of caspase-3.

• Molecules and Cells
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• v.24 no.2
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• pp.261-267
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• 2007

Apoptotic signals are typically accompanied by activation of aspartate-specific cysteine proteases called caspases, and caspase-3 and -7 play crucial roles in the execution of apoptosis. Previously, using the proteomic approach, protein disulfide isomerase (PDI) was found to be a candidate substrate of caspase-7. This abundant 55 kDa protein introduces disulfide bonds into proteins (via its oxidase activity) and catalyzes the rearrangement of incorrect disulfide bonds (via its isomerase activity). PDI is abundant in the ER but is also found in non-ER locations. In this study we demonstrated that PDI is cleaved by caspase-3 and -7 in vitro. In addition, in vivo experiment showed that it is cleaved during etoposide-induced apoptosis in HL-60 cells. Subcellular fractionation showed that PDI was also present in the cytosol. Furthermore, only cytosolic PDI was clearly digested by caspase-3 and -7. It was also confirmed by confocal image analysis that PDI and caspase-7 partially co-localize in both resting and apoptotic MCF-7 cells. Overexpression of cytosolic PDI (ER retention sequence deleted) inhibited cell death after an apoptotic stimulus. These data indicate that cytosolic PDI is a substrate of caspase-3 and -7, and that it has an anti-apoptotic action.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.4
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• pp.888-894
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• 2009

It has been reported that silibinin, a natural polyphenolic flavonoid, induces cell death in various cancer cell types. However, the underlying mechanisms by which silibinin induces apoptosis in human glioma cells are poorly understood. The present study was therefore undertaken to examine the effect of silibinin on glioma cell apoptosis and to determine its underlying mechanism in human glioma cells. Apoptosis was estimated by FACS analysis. Reactive oxygen species (ROS) generation and mitochondrial membrane potential (${\Psi}m$) were measured using fluorescence dyes DCFH-DA and $DiOC_6$(3), respectively. Cytochrome c release from mitochondria and caspase-3 activation were estimated by Western blot analysis using specific antibodies. Exposure of cells to 30 mM silibinin induced apoptosis starting at 6 h, with increasing effects after 12-48h in a time-dependent manner. Silibinin caused ROS generation and disruption of ym, which were associated with the silibinin-induced apoptosis. The silibinin-induced ROS generation and disruption in ym were prevented by inhibitors of mitochondrial electron transport chain. The hydrogen peroxide scavenger catalase blocked ROS generation and apoptosis induced by silibinin. Silibinin induced cytochrome c release into cytosolic fraction and its effect was prevented by catalase and cyclosporine A. Silibinin treatment caused caspase-3 activation, which was inhibited by DVED-CHO and cyclosporine A. Pretreatment of caspase inhibitors also protected against the silibinin-induced apoptosis. These findings indicate that ROS generation plays a critical role in the initiation of the silibinin-induced apoptotic cascade by mediation of the mitochondrial apoptotic pathway including the disruption of ${\Psi}m$, cytochrome c release, and caspase-3 activation.

• Journal of Life Science
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• v.25 no.9
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• pp.984-992
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• 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 Physiology and Pharmacology
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• v.27 no.4
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• pp.383-398
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• 2023

Dihydroaustrasulfone alcohol (DA), the synthetic precursor of a natural compound (austrasulfone) isolated from the coral species Cladiella australis, has shown cytotoxic effects against cancer cells. However, it is unknown whether DA has antitumor effects on nasopharyngeal carcinoma (NPC). In this study, we determined the antitumor effects of DA and investigated its mechanism of action on human NPC cells. The MTT assay was used to determine the cytotoxic effect of DA. Subsequently, apoptosis and reactive oxygen species (ROS) analyses were performed by using flow cytometry. Apoptotic and PI3K/AKT pathway-related protein expression was determined using Western blotting. We found that DA significantly reduced the viability of NPC-39 cells and determined that apoptosis was involved in DA-induced cell death. The activity of caspase-9, caspase-8, caspase-3, and PARP induced by DA suggested caspase-mediated apoptosis in DA-treated NPC-39 cells. Apoptosis-associated proteins (DR4, DR5, FAS) in extrinsic pathways were also elevated by DA. The enhanced expression of proapoptotic Bax and decreased expression of antiapoptotic BCL-2 suggested that DA mediated mitochondrial apoptosis. DA reduced the expression of pPI3K and p-AKT in NPC-39 cells. DA also reduced apoptosis after introducing an active AKT cDNA, indicating that DA could block the PI3K/AKT pathway from being activated. DA increased intracellular ROS, but N-acetylcysteine (NAC), a ROS scavenger, reduced DA-induced cytotoxicity. NAC also reversed the chances in pPI3K/AKT expression and reduced DA-induced apoptosis. These findings suggest that ROS-mediates DA-induced apoptosis and PI3K/AKT signaling inactivation in human NPC cells.

• The Journal of Korean Medicine
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• v.36 no.4
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• pp.19-34
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• 2015

Objectives: This study was performed to investigate the anti-tumor effect of O. japonicus extracts on intrahepatic cholangiocarcinoma cell line SNU-1079. Methods: Cholangiocarcinoma SNU-1079 cells were treated with various concentrations of O. japonicus DW and EtOH extracts ($0-300{\mu}g/ml$) for 24, 48 or 72 h. Cell viability was evaluated through a PMS/MTS assay, and the apoptosis rate was examined through ELISA assay and flow cytometry analysis. The mRNA expression of apoptosis- and cell cycle progression-related genes (Bcl-2, Mcl-1, Bax, Survivin, Cyclin D1, and p21) was evaluated using real-time PCR, and the caspase activity was examined using immunoblot analysis. Results: O. japonicus extracts inhibited cell proliferation and increased apoptosis rate in both ELISA assay and flow cytometry analysis. O. japonicus extracts decreased Bcl-2, Mcl-1, Survivin, and Cyclin D1 mRNA expression and increased Bax mRNA level. O. japonicus extracts also increased Caspase-3 activation. Overall, O. japonicus DW extracts were more effective than EtOH extracts. Conclusions: O. japonicus inhibited cell proliferation and induced apoptosis in SNU-1079 cells via mitochondria -mediated intrinsic pathway, which leads to Caspase-3 activation. The results indicate that O. japonicus is a potential therapeutic herb with anti-tumor effect against intrahepatic cholangiocarcinoma.

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.169-183
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• 2003

Tooth movement by orthodontic force effects great tissue changes within the periodontium, especially by shifting the blood flow in the pressure side and resulting in a hypoxic state of low oxygen tension. The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3El osteoblasts, the main cells in bone remodeling during orthodontic tooth movement. MC3T3El osteoblasts under hypoxic conditions ($2\%$ orygen) resulted in apoptosis in a time-dependent manner as estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pancaspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, Western blot analysis was performed using anti-caspase-3 or -6 antibodies. The 10-kDa protein, corresponding to the active products of caspase-3, and the 10-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which the processing of the full length form of caspase-3 and -6 was evident. While a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, which was typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we observed that pre-treatment with SB203580, a selective p38 mitogen activated protein kinase inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203S80 suppressed caspase-3 and -6-like protease activity by hypoxia up to $50\%$. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAPK -JNK/SAPK or ERK- was either only modestly activated or not at all. These results suggest that p38 MAPK is involved in hypoxia-induced apoptosis in MC3T3El osteoblasts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1119-1125
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• 2010

To evaluate resveratrol as a prostate cancer preventive material, we investigated its anti-proliferative and apoptotic effects in RC-58T/h/SA#4 primary human prostate cancer cells. Resveratrol significantly decreased the number of viable RC-58T/h/SA#4 cells in a dose- and time-dependent manner. Resveratrol showed cytotoxicity against RC-58T/h/SA#4, LNCaP, PC-3 human prostate cancer cells with $IC_{50}$ values of 245, 320 and $340\;{\mu}M$, respectively. However the cytotoxic potential of resveratrol against normal RWPE-1 cells was lower ($IC_{50}=982\;{\mu}M$). Resveratrol induced cell death as evidenced by the increased formation of apoptotic bodies, nuclear condensation, sub-G1 phase, and DNA fragmentation. Resveratrol activated initiator caspases 8, and 9 as well as effector caspase 3 in a dose-dependent manner. Furthermore, the general caspase inhibitor z-VAD-fmk significantly inhibited resveratrol-induced apoptosis compared to cells without treatment. These results clearly indicate that resveratrol-induced apoptosis was dependent on caspase activation. Further, resveratrol modulated the down regulation of Bcl-2 (anti-apoptotic), and Bid. However, the level of Bax (pro-apoptotic) remained unchanged. These results suggest that resveratrol induced apoptosis in RC-58T/h/SA#4 cells via a mitochondrial-mediated caspase-dependent pathway, suggesting therapeutic potential against prostate cancer.

• Biomedical Science Letters
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• v.12 no.2
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• pp.57-63
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• 2006

Deazaadenosine analogs such as 3-deazaadenosine (DZA), 3-deazaaristeromycin (DZAri) and ara-3-deazaadenine (DZAra-A) were developed as inhibitors of S-adenosylhomocysteine (Ado-Hcy) hydrolase (EC 3.3.1.1). These analogs were reported to induce apoptosis in human and murine leukemic cells. But, the mechanism involved in this apoptosis was not clarified yet. In the present study, we analyze the apoptosis induced by deazaadenosine analogs in human cervival cancer cell line, HeLa and the effect of Bcl-2 on this apoptosis. Whereas neither DZAri nor DZAra-A showed inhibitory effect on HeLa cell growth, DZA induced apoptosis in HeLa cells accompanied by cytochrome c release and activation of various caspases such as caspase-2,-8,-9 and -3. In HeLa-bcl-2 cell line, a stable transfectant of HeLa cell to overexpress Bcl-2, cytochrome c release, activation of all these caspases and the resulted apoptosis by DZA were completely prevented. By in vitro assay of cytochrome c release, in addition, DZA induced cytochrome c release from purified mitochondria of HeLa-pcDNA3 cells, but not HeLa-bcl-2 cells, even in the absence of cytosolic fraction. Therefore, it can be suggested that DZA might damage directly mitochondria leading to activate intrinsic pathway of caspase and thus induce apoptosis. DZA-induced apoptosis in HeLa cells may be in a bcl-2-inhibitable manner and irrelative of Ado-Hcy hydrolase.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7919-7923
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• 2014

20(S)-Protopanaxadiol (PPD), a ginsenoside isolated from Pananx quinquefolium L., has been shown to inhibit growth and proliferation in several cancer cell lines. The aim of this study was to evaluate its anticancer activity in human breast cancer cells. MCF-7 cells were incubated with different concentrations of 20(S)-PPD and cytotoxicity was evaluated by MTT assay. Occurrence of apoptosis was detected by DAPI and Annexin V-FITC/PI double staining. Mitochondrial membrane potential was measured with Rhodamine 123. The Bcl-2 and Bax expression were determined by Western blot analysis. Caspase activity was measured by colorimetric assay. 20(S)-PPD dose-dependently inhibited cell proliferation in MCF-7 cells, with an $IC_{50}$ value of $33.3{\mu}M$ at 24h. MCF-7 cells treated with 20(S)-PPD presented typical apoptosis, as observed by morphological analysis in cell stained with DAPI. The percentages of annexin V-FITC positive cells were 8.92%, 17.8%, 24.5% and 30.5% in MCF-7 cells treated with 0, 15, 30 and $60{\mu}M$ of 20(S)-PPD, respectively. Moreover, 20(S)-PPD could induce mitochondrial membrane potential loss, up-regulate Bax expression and down-regulate Bcl-2 expression. These events paralleled activation of caspase-9, -3 and PARP cleavage. Apoptosis induced by 20(S)-PPD was blocked by z-VAD-fmk, a pan-caspase inhibitor, suggesting induction of caspase-mediated apoptotic cell death. In conclusion, the 20(S)-PPD investigated is able to inhibit cell proliferation and to induce cancer cell death by a caspase-mediated apoptosis pathway.