• Journal of Life Science
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• v.23 no.4
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• pp.518-528
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• 2013

Scutellaria baicalensis, belonging to the family Labiatae, is widely distributed in Korea, China, Mongolia, and eastern Siberia. It has been used in traditional medicine for various diseases, such as dysentery, pyrexia, jaundice, and carbuncles. In addition, S. baicalensis is reported to possess various beneficial pharmacological activities, including anti-inflammatory, antidiabetic, antiviral, antihypertension, antioxidant, and anticancer effects. However, the molecular mechanisms of its anticancer activity have not been clearly elucidated. In the present study, we investigated the proapoptotic effects of ethanol extract of S. baicalensis (EESB) on human renal cell carcinoma Caki-1 cells. The anti-proliferative activity of EESB was associated with apoptosis induction, which was associated with the up-regulation of death receptor 4, the Fas ligand, and Bax and the down-regulation of Bid, XIAP, and cIAP-1 proteins. EESB treatment also induced mitochondrial dysfunction, proteolytic activation of caspase-3, -8, and -9 and degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase, ${\beta}$-catenin, and phospholipase C-${\gamma}1$. However, pretreatment of a pan-caspase inhibitor, z-VAD-fmk, significantly attenuated the EESB-induced apoptosis. Taken together, these findings suggest that EESB may be a potential chemotherapeutic agent. Further studies will be needed to identify the active compounds that confer the anticancer activity of S. baicalensis.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.287-294
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• 2016

The effect of kaempferol (3,5,7,4-tetrahydroxyflavone), a flavonoid compound that was identified in barnyard millet (Echinochloa crus-galli var. frumentacea) grains, on G₂-checkpoint and apoptotic pathways was investigated in human acute leukemia Jurkat T cell clones stably transfected with an empty vector (J/Neo) or a Bcl-xL expression vector (J/Bcl-xL). Exposure of J/Neo cells to kaempeferol caused cytotoxicity and activation of the ATM/ATR-Chk1/Chk2 pathway, activating the phosphorylation of p53 (Ser-15), inhibitory phosphorylation of Cdc25C (Ser-216), and inactivation of cyclin-dependent kinase 1 (Cdk1), with resultant G₂-arrest of the cell cycle. Under these conditions, apoptotic events, including upregulation of Bak and PUMA levels, Bak activation, mitochondrial membrane potential (Δψm) loss, activation of caspase-9, -8, and -3, anti-poly (ADP-ribose) polymerase (PARP) cleavage, and accumulation of apoptotic sub-G₁ cells, were induced without accompanying necrosis. However, these apoptotic events, except for upregulation of Bak and PUMA levels, were completely abrogated in J/Bcl-xL cells overexpressing Bcl-xL, suggesting that the G₂-arrest and the Bcl-xL-sensitive mitochondrial apoptotic events were induced, in parallel, as downstream events of the DNA-damage-mediated G₂-checkpoint activation. Together these results demonstrate that kaempferol-mediated antitumor activity toward Jurkat T cells was attributable to G₂-checkpoint activation, which caused not only G₂-arrest of the cell cycle but also activating phosphorylation of p53 (Ser-15) and subsequent induction of mitochondria-dependent apoptotic events, including Bak and PUMA upregulation, Bak activation, Δψm loss, and caspase cascade activation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.649-659
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• 2011

To examine the anti-cancer effects of Lepidium virginicum L., the anti-proliferative and pro-apoptotic effects of a water extract of L. virginicum leaves (WELVL) and of L. virginicum roots (WELVR) were investigated in HCT116 human colon carcinoma cells. The treatment of HCT116 cells with WELVL and WELVR resulted in the inhibition of growth and morphological changes in a concentration-dependent manner by inducing apoptosis. The growth inhibition and apoptosis induction by WELVR was stronger than that of WELVL thus, we determined that WELVR was the more optimal extract for this study. The increased apoptotic events in HCT116 cells caused by WELVR were associated with an up-regulation of Fas ligand, Bax, and Bad expression, a down-regulation of Bcl-2, Bcl-$_XL$, and Bid expression, and a decrease in the mitochondrial membrane potential (MMP, ${\Delta}{\psi}m$). WELVR treatment induced the proteolytic activation of caspase-3, -8, and -9, and the degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase (PARP), ${\beta}$-catenin, and phospholipase C-${\gamma}1$ (PLC-${\gamma}1$). In addition, apoptotic cell death induced by WELVR was correlated with a down-regulation of inhibitors of the apoptosis protein (IAP) family, such as the X-linked inhibitor of apoptosis protein (XIAP), cIAP-1, and cIAP-2. These findings suggest that the WELVR-induced inhibition of cell proliferation is associated with the induction of apoptotic cell death. WELVR may be a potential chemotherapeutic agent for the control of HCT116 human colon carcinoma cells.

• International Journal of Oral Biology
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• v.42 no.4
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• pp.183-190
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• 2017

Ficus carica L. (common fig), one of the first plants cultivated by humans, originated in the Mediterranean basin and currently grows worldwide, including southwest Asia and South Korea. It has been used as a traditional medicine for treatment of metabolic, cardiovascular, and respiratory diseases as well as hemorrhoids and skin infections. Its pharmacological properties have recently been studied in detail, but research on the anti-cancer effect of its latex has been only been studied on a limited basis on several cell lines, such prostate cancer, breast cancer, and leukemia. In this study, we investigated the anti-cancer activity of the latex of Ficus carica L.and its underlying mechanism in FaDu human hypopharynx squamous carcinoma cells. (See Ed. note above) We confirmed through SDS-PAGE analysis and gelatinolytic activity analysis that the latex of Ficus carica contains cysteine protease ficin. Our data showed that the latex inhibited cell growth in a dose-dependent manner. In addition, the latex treatment markedly induced apoptosis in FaDu cells as determined by FACS analysis, elevated expression level of cleaved caspase-9, -3 and PARP (poly (ADP-ribose) polymerase), and. increased the expression of Bax (pro-apoptotic factor) while decreasing the expression of Bcl-2 (anti-apoptotic factor). Taken together, these results suggested that latex containing the ficin inhibited cell growth and induced apoptosis by caspase and the Bcl-2 family signaling pathway in FaDu human hypopharynx squamous carcinoma cells. These findings point to the potential of latex of Ficus carica to provide a novel chemotherapeutic drug due to its growth inhibition effects and induction of apoptosis in human oral cancer cells.

• Journal of Pharmacopuncture
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• v.18 no.2
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• pp.26-32
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• 2015

Objectives: Rheum undulatum L. has traditionally been used for the treatment of many diseases in Asia. However, its anti-proliferative activity in cancer has still not been studied. In the present study, we investigated the anti-cancer effects of methanol extract of Rheum undulatum L. (MERL) on human adenocarcinoma gastric cell lines (AGS). Methods: To investigate the anti-cancer effect of MERL on AGS cells, we treated the AGS cells with varying concentrations of MERL and performed 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. Cell cycle analyses, measurements of the mitochondrial membrane potential (MMP), caspase activity assays and Western blots were conducted to determine whether AGS cell death occurred by apoptosis. Results: Treatment with MERL significantly inhibited growth of AGS cells in a concentration dependent manner. MERL treatment in AGS cells leaded to increased accumulation of apoptotic sub G1 phase cells in a concentration dependent manner. In control cultures, 5.38% of the cells were in the sub G1 phase. In MERL treated cells, however, this percentage was significantly increased (9.95% at $70{\mu}g/mL$, 15.94% at $140{\mu}g/mL$, 26.56% at $210{\mu}g/mL$ and 38.08% at $280{\mu}g/mL$). MERL treatment induced the decreased expression of pro-caspase-8 and -9 in a concentration dependent manner, whereas the expression of the active form of caspase-3 was increased. A subsequent Western blot analysis revealed increased cleaved levels of poly (ADP-ribose) polymerase (PARP) protein. Also, treatment with MERL increased the activities of caspase-3 and -9 compared with the control. MERL treatment increased the levels of the pro-apoptotic truncated Bid (tBid) and Bcl2 Antagonist X (Bax) proteins and decreased the levels of the anti-apoptotic B-cell lymphoma 2 (Bcl-2) protein, whose is the stabilization of mitochondria. However, inhibitions of p38, extracellular signal regulated kinases (ERKs) and C-Jun N-terminal kinases (JNK) by MERL treatment did not affect cell death. Conclusion: These results suggest that MERL mediated cell death is associated with an intrinsic apoptotic pathway in AGS cells.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.289-295
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• 2006

Sodium fluoride (NaF) has been shown to be cytotoxic and elicit inflammatory response in human. However, the cellular mechanisms underlying NaF-induced cytotoxicity in periodontal tissues have not yet been elucidated. This study is aimed to investigate the mechanisms of NaF-induced apoptosis in human gingival fibroblast (HGF). NaF decreased the cell viability of HGF in a dose- and time-dependent manner. NaF gave rise to apoptotic morphological changes including cell shrinkage, chromatin condensation, and DNA fragmentation. However, NaF did not affect the production of ROS. In addition, NaF augumented cytochrome c release from mitochondria into the cytosol, and enhanced caspase -9 and -3 activities., cleavage (85 kDa fragments) of poly (ADP-ribose) polymerase (PARP) and upregulation of voltage-dependent anion channel (VDAC) 1. These results demonstrated that NaF-induced apoptosis in HGF may be mediated with mitochondria. Furthermore, NaF elevated caspase-8 activity and upregulated Fas-ligand (Fas-L), suggesting involvement of death receptor mediated pathway in NaF-induced apoptosis. Expression of Bcl-2, an anti-apoptotic Bcl-2 family, was downregulated, whereas expression of Bax, a pro-apoptotic Bcl-2 family, was not affected in NaF-treated HGF. These results suggest that NaF induces apoptosis in HGF through both mitochondria- and death receptor-mediated pathway mediated by Bcl-2 family.

• Journal of Life Science
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• v.26 no.7
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• pp.847-854
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• 2016

Cordycepin, a derivative of the nucleoside adenosine, is one of the active components extracted from fungi of genus Cordyceps, and has been shown to have many pharmacological activities. In this study, we investigated the effects of cordycepin on proliferation and apoptosis of human gastric cancer AGS cells, and its possible mechanism of action. Treatment of cordycepin resulted in significant decrease in cell viability of AGS cells in a concentration-dependent manner. A concentration-dependent apoptotic cell death was also measured by agarose gel electrophoresis and flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in an enhanced expression of tumor necrosis factor-related apoptosis-inducing ligand, death receptor 5 and Fas ligand. Furthermore, up-regulation of pro-apoptotic Bax, and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL expression were also observed in cordycepin-treated AGS cells. These were followed by activation of caspases (caspase-9, -8 and -3), subsequently leading to poly (ADP-ribose) polymerase cleavage. Taken together, these findings indicate that cordycepin induces apoptosis in AGS cells through regulation of multiple apoptotic pathways, including death receptor and mitochondria. Although further mechanical studies are needed, our results revealed that cordycepin can be regarded as a new effective and chemopreventive compound for human gastric cancer treatment.

• Journal of Life Science
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• v.28 no.11
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• pp.1268-1276
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• 2018

The cytidine analog decitabine (DEC) acts as a nucleic acid synthesis inhibitor, whereas ammonium pyrrolidine dithiocarbamate (PDTC) is an inhibitor of nuclear factor-${\kappa}B$. The aim of this study was to investigate the possible synergistic inhibitory effect of these two inhibitors on proliferation of human gastric cancer AGS cells. The inhibitory effect of PDTC on AGS cell proliferation was significantly increased by DEC in a concentration-dependent manner, and this inhibition was associated with cell cycle arrest at the G2/M phase and the induction of apoptosis. This induction of apoptosis by the co-treatment with PDTC and DEC was related to the induction of DNA damage, as assessed by H2AX phosphorylation. Further studies demonstrated that co-treatment with PDTC and DEC induced the disruption of mitochondrial membrane potential, increased the generation of intracellular reactive oxygen species (ROS) and the expression of pro-apoptotic Bax, and down-regulated the expression of anti-apoptotic Bcl-2, ultimately resulting in the release of cytochrome c from the mitochondria into the cytoplasm. Co-treatment with PDTC and DEC also activated caspase-8 and caspase-9, which are representative caspases of the extrinsic and intrinsic apoptosis pathways. Co-treatment also activated caspase-3, which was accompanied by proteolytic degradation of poly (ADP-ribose) polymerase. Taken together, these data clearly indicated that co-treatment with PDTC and DEC suppressed the proliferation of AGS cells by increasing DNA damage and activating the ROS-mediated extrinsic and intrinsic apoptosis pathways.

• Journal of Life Science
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• v.29 no.7
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• pp.809-816
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• 2019

The ubiquitous plant metabolite p-coumaric acid (p-CA) has antioxidant and anti-inflammatory properties, but its anti-cancer activity has not been established in gastric cancer cell lines. In this study, we investigated the effects of p-CA on the proliferation and transcriptome profile of SNU16 gastric cancer cells. Treatment with p-CA induced apoptosis of the SNU-16 cells by regulating the expression of pro-apoptotic and anti-apoptotic proteins, such as Bcl-2, poly (ADP-ribose) polymerase (PARP), Bax, procaspase-3, and cleaved-caspase-3. The genes differentially expressed in response to p-CA treatment of the SNU-16 cells were identified by RNA sequencing analysis. Genes regulated by p-CA were involved mainly in the inflammatory response, apoptotic processes, cell cycle, and immune response. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the phosphatidylinositol-3-kinase-Akt and cancer signaling pathways were altered by p-CA. Protein-protein interaction (PPI) network analysis also revealed that p-CA treatment was correlated with differential expression of genes associated with the inflammatory response and cancer. Collectively, these results suggest that p-CA has potential utility in gastric cancer prevention.

• Journal of Life Science
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• v.29 no.9
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• pp.977-985
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• 2019

Aster yomena (Kitam.) Honda is an edible vegetable and perennial herb belonging to the Asteraceae family, and has been used for a long time for the prevention and treatment of various diseases. Although leaf extracts of A. yomena are known to have antioxidant and anti-inflammatory effects, accurate efficacy assessments are still inadequate. In this study, we investigated whether the antioxidant efficacy of ethanol extract of A. yomena leaf (EEAY) is correlated with the anti-inflammatory effect in RAW 264.7 macrophages. The results showed that EEAY significantly inhibited the hydrogen peroxide ($H_2O_2$)-induced growth inhibition in RAW 264.7 cells, which was associated with increased expression of nuclear factor erythroid 2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1). EEAY pretreatment also effectively prevented $H_2O_2$-induced reactive oxygen species generation and apoptosis through inhibition of caspase-3 activation and poly (ADP-ribose) polymerase degradation. Additionally, EEAY significantly increased the expression and production of interleukin-10, a representative anti-inflammatory cytokine, which was associated with increased expression of toll-like receptor 4 and myeloid differentiation factor 88 at transcriptional and translational levels. Furthermore, the increased production of nitric oxide (NO) by lipopolysaccharide was markedly abolished under the condition of EEAY pretreatment, and the inhibitory effect of NO production by EEAY was further increased by hemin, an HO-1 inducer. Overall, our results suggest that EEAY is able to activate the Nrf2/HO-1 signaling pathway to protect RAW 264.7 macrophages from oxidative and inflammatory stress.