• Clinical and Experimental Pediatrics
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• v.52 no.6
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• pp.696-700
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• 2009

Purpose : We screened more than 350 compounds with an endoperoxide ring structure in search of an anti-leukemic drug and found that compound 127 (c-127) could induce significant cytotoxicity in HL-60 cells. In this study, we investigated the molecular mechanisms of compound 127-induced antitumor activity on HL-60 cells. Methods : HL-60 cells were cultured in Rosewell Park Memorial Institute 1640 and cell viability was measured by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], a tetrazole assay. Apoptosis was assessed by a DNA fragmentation test. Apoptotic machineries were determined by Western blot analysis. Results : C-127 could induce a cytotoxic effect at 24 h and apoptosis at 6 h, which was demonstrated with MTT assay and DNA fragmentation test, respectively. The apoptotic effect of this drug was caused by the activation of the intracellular caspase-8,3 activation, the cleavage of pro-apoptotic Bid, and the increase of c-Jun expression accompanied with JNK (Jun N-terminal kinases) phosphorylation. On the contrary, it increased the expression of anti-apoptotic Bcl-2 levels, leading to the induction of the induction of anti-apoptotic effect. Taken together, the present study demonstrated that c-127 was a potent inducer of cytotoxicity on HL-60 cells through apoptotic mechanisms, which included the activation of caspase family, the regulation of Bcl-2 family, and the activation of JNK signaling pathway. Conclusion : Our results suggest that c-127 has a strong antitumor activity through the regulation of various apoptotic machineries on HL-60 cells. The compound may be utilized as an effective and potentially therapeutic drug in leukemia.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.30-36
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• 2010

This study was conducted to investigate the effects of blueberry extract on cell death, ROS and gene expression patterns associated with the anti-cancer activity in human breast cancer MCF7 cells. To accomplish this, 20 mg/mL concentration of blueberry extract was added to the cell culture for 0, 6, 12, 24 or 48 h, after which the effects were evaluated by various analyses. MTT assay showed that the cellular activities decreased rapidly during the first 12 h of treatment. During this period, dual staining with Hoechst33322 and propidium iodide also produced a similar trend in which the dead or dying cells increased sharply. Furthermore, evaluation of BrdU incorporation as an index for cell proliferation revealed a marked decrease during the first 12 h of treatment, suggesting that anticancer activity involves the inhibition of cell proliferation and induces cell death. ROS also increased according to the duration of the treatment, indicating intracellular accumulation is associated with the cell death. RT-PCR analysis revealed significant decreases in anti-apoptotic (Bax) and increases in pro-apoptotic gene expressions (Bci-2, caspase- 3, and 9) (p<0.05). Taken these together, blueberry extract induces ROS accumulation in MCF7 cells, causing inhibition of cell proliferation and eventually leading to cell death. This cell death was associated with apoptotic gene expression in blueberry-treated cells for up to 24 h.

• ALGAE
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• v.30 no.4
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• pp.313-323
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• 2015

Lipid peroxidation means the oxidative degradation of lipids. The process from the cell membrane lipids in an organism is generated by free radicals, and result in cell damage. Phlorotannins, well-known marine brown algal polyphenols, have been utilized in functional food supplements as well as in medicine supplements to serve a variety of purposes. In this study, we assessed the potential anti-lipid peroxidation activity of phlorofucofuroeckol-A (PFF-A), one of the phlorotannins, isolated from Ecklonia cava by centrifugal partition chromatography in 2,2-azobis (2-amidinopropane) dihydrochloride (AAPH)-stimulated Vero cells and zebrafish system. PFF-A showed the strongest scavenging activity against alkyl radicals of all other reactive oxygen species (ROS) and exhibited a strong protective effect against ROS and a significantly strong inhibited of malondialdehyde in AAPH-stimulated Vero cells. The apoptotic bodies and pro-apoptotic proteins Bax and caspase-3, which were induced by AAPH, were strongly inhibited by PFF-A in a dose-dependent manner and expression of Bcl-xL, an anti-apoptotic protein, was induced. In the AAPH-stimulated zebrafish model, additionally PFF-A significantly inhibited ROS and cell death, as well as exhibited a strong protective effect against lipid peroxidation. Therefore, these results suggest that PFF-A has excellent protective effects against ROS and lipid peroxidation induced by AAPH in both an in vitro Vero cell model and an in vivo zebrafish model.

• Journal of Acupuncture Research
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• v.34 no.1
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• pp.1-9
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• 2017

Objectives : We investigated the synergistic effects of bee venom (BV) and natural killer (NK) cells on B16F10 melanoma cell apoptosis mediated by IL-4. Methods : We performed a cell viability assay to determine whether BV can enhance the inhibitory effect of NK-92MI cells on the growth of B16F10 melanoma cells, and western blot analysis to detect changes in the expression of IL-4, $IL-4R{\alpha}$, and other apoptosis-related proteins. EMSA was performed to observe the activity of STAT6. To confirm that the inhibitory effect of BV and NK cells was mediated by IL-4, the above tests were repeated after IL-4 silencing by siRNA (50 nM). Results : B16F10 melanoma cells co-cultured with NK-92MI cells and simultaneously treated by BV ($5{\mu}g/ml$) showed a higher degree of proliferation inhibition than when treated by BV ($5{\mu}g/ml$) alone or co-cultured with NK-92MI cells alone. Expression of IL-4, $IL-4R{\alpha}$, and that of other pro-apoptotic proteins was also enhanced after co-culture with NK-92MI cells and simultaneous treatment with BV ($5{\mu}g/ml$). Furthermore, the expression of anti-apoptotic bcl-2 decreased, and the activity of STAT6, as well as the expression of STAT6 and p-STAT6 were enhanced. IL-4 silencing siRNA (50 nM) in B16F10 cells, the effects of BV treatment and NK-92MI co-culture were reversed. Conclusion : These results suggest that BV could be an effective alternative therapy for malignant melanoma by enhancing the cytotoxic and apoptotic effect of NK cells through an IL-4-mediated pathway.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.283-288
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• 2021

This study investigated the anticancer activity of methanol extract from Platycarya strobilacea leaf in AGS human gastric cancer cells. We determined the cell viability effect of P. strobilacea using MTS assay. Apoptosis induction and cell cycle arrest were confirmed by fluorescein isothiocyanate and propidium iodide staining using cellometer K2. The mRNA expression levels of the Bcl-2 family were confirmed by reverse transcription-polymerase chain reaction. The cell viability was decreased in a dose-dependent manner treated with different concentrations of P. strobilacea. Total, early, and late apoptotic cells were dramatically increased, and the cell cycle was arrested at the sub-G1 phase. The mRNA expressions of Bcl-2 and Bcl-xL were reduced, whereas pro-apoptotic factors, Bax and Bak, were increased in a dose-dependent manner. These results suggested that P. strobilacea leaf extract induced significant apoptotic activity through an intrinsic mitochondria pathway.

• Journal of Life Science
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• v.28 no.1
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• pp.50-57
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• 2018

Millettia erythrocalyx, a species of plant in the Fabaceae family, is widely distributed in the tropical and subtropical regions of the world, such as the Indies, China, and Thailand. The antiviral activity of flavonoids from M. erythrocalyx has been reported; however, the antioxidative and anticancer activities of M. erythrocalyx remain unclear. In this study, we evaluated the antioxidative and anticancer effects of ethanol extract of M. erythrocalyx (EEME) and the molecular mechanism of its anticancer activity in human hepatocellular carcinoma HepG2 cells. EEME exhibited significant antioxidative effects, with a concentration at 50% inhibition ($IC_{50}$) value of $2.74{\mu}g/ml$, as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay; moreover, it inhibited cell proliferation in a dose-dependent manner in HepG2 cells. Cell cycle analyses showed that EEME induced HepG2 cell accumulation in the subG1 phase in a dose-dependent manner. EEME also induced apoptosis of HepG2 cells, with increases in apoptotic cells and apoptotic bodies, as detected by Annexin V and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. Treatment with EEME resulted in increased expression of First apoptosis signal (Fas), a death receptor, and Bcl-2-associated X protein (Bax), a proapoptotic protein, and the activation of caspase-3, 8, and 9, resulting in the cleavage of poly (Adenosine diphosphate-ribose) polymerase (PARP). Collectively, these results suggest that EEME may exert an anticancer effect in HepG2 cells by inducing apoptosis via both the intrinsic and extrinsic pathways.

• Journal of Life Science
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• v.21 no.12
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• pp.1678-1688
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• 2011

The apoptogenic effect of p-coumaric acid, a phenolic acid found in various edible plants, on human acute leukemia Jurkat T cells was investigated. Exposure of Jurkat T cells to p-coumaric acid (50-$150{\mu}M$) caused cytotoxicity and TdT-mediated dUTP nick-end labeling (TUNEL)-positive apoptotic DNA fragmentation along with Bak activation, ${\Delta}{\psi}m$ loss, activation of caspase-9, -3, -7, and -8, and PARP degradation in a dose-dependent manner. However,these apoptotic events were completely abrogated in Jurkat T cells overexpressing Bcl-2.Under these conditions, necrosis was not accompanied. Pretreatment of the cells with the pan-caspase inhibitor (z-VAD-fmk) could prevent p-coumaric acid-induced sub-$G_1$ peak representing apoptotic cells, whereas it failed to block ${\Delta}{\psi}m$ loss, indicating that the activation of caspase cascade was prerequisite for p-coumaric acid-induced apoptosis as a downstream event of ${\Delta}{\psi}m$ loss. FADD- and caspase-8-positive wild-type Jurkat T cell clone A3, FADD-deficient Jurkat T cell clone I2.1, and caspase-8-deficient Jurkat T cell clone I9.2 exhibited similar susceptibilities to the cytotoxicity of p-coumaric acid, excluding an involvement of Fas/FasL system in triggering the apoptosis. The apoptogenic activity of p-coumaric acid is more potent in malignant Jurkat T cells than in normal human peripheral T cells. Together, these results demonstrated that p-coumaric acid-induced apoptogenic activity in Jurkat T cellswas mediated by Bak activation, ${\Delta}{\psi}m$ loss, and subsequent activation of multiple caspases such as caspase-9, -3, -7, and-8, and PARP degradation, which could be regulated by anti-apoptotic protein Bcl-2.

• BMB Reports
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• v.51 no.6
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• pp.302-307
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• 2018

Pinosylvin is known to have anti-inflammatory activity in endothelial cells. In this study, we found that pinosylvin had a pro-apoptotic activity in lipopolysaccharide (LPS)-preconditioned leukocytes. This finding suggests that pinosylvin has an effect on the resolution of inflammation. To understand the detailed mechanism, we examined if pinosylvin enhances cyclooxygenase (COX) or lipoxygenase (LOX) activity in THP-1 and U937 cells. LOX activity was found to be markedly increased by pinosylvin, whereas COX activity was not altered. Furthermore, we found that pinosylvin enhanced both levels of ALOX 15 mRNA and protein, implying that LOX activity, elevated by pinosylvin, is attributed to upregulation of ALOX 15 expression. From this cell signaling study, pinosylvin appeared to promote phosphorylations of ERK and JNK. ERK or JNK inhibitors were found to attenuate ALOX 15 expression and LPS-induced apoptosis promoted by pinosylvin. In conclusion, pinosylvin enhances the apoptosis of LPS-preconditioned leukocytes by up-regulating ALOX 15 expression through ERK and JNK. These findings suggest that pinosylvin may induce the resolution of inflammation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.751-758
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• 2003

In our previous studies, we reported that Selaginella Tamariscina(ST) induced apoptotic cell death in HL-60 cells selectively. The cell viability after treatment with extract of ST was quantified by MTT assay and trypan bleu exclusion method. The results showed that application with ST in HL-60 induced 40% cell death at the concentration of 400 ㎍/ml. The cancericidic effect of Selaginella Tamariscina was mediated by apoptosis. Thus, HL-60 cells exposed to Selaginella Tamariscina displayed the DNA fragmentation ladder and nucleus chromatin condensation characteristic for apoptosis. The enzyme activity of caspase-3 and actived caspase-3 protein were markedly increased in HL-60 cells treated with the extract of Selaginella Tamariscina. In addition, the extract of Selaginella Tamariscina induced cleavage of PARP, a known substrate for caspase-3. The expression of Bcl-2, anti-apoptotic protein, was decreased by treatment of the aqueous extract of Selaginella Tamariscina in a dose-dependent manner. And the expression of pro-apoptotic Bax protein was increased. In conclusion, our results suggest that the extract of Selaginella Tamariscina may induce the apoptotic death of HL-60 cells via activation of caspase-3, cleavage of PARP protein, depletion of cellular ATP levels and Bcl-2 degradation.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.599-607
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• 2017

Most normal cells express L-type amino acid transporter 2 (LAT2). However, L-type amino acid transporter 1 (LAT1) is highly expressed in many tumor cells and presumed to support their increased growth and proliferation. This study examined the effects of JPH203, a selective LAT1 inhibitor, on cell growth and its mechanism for cell death in Saos2 human osteosarcoma cells. FOB human osteoblastic cells and Saos2 cells expressed LAT1 and LAT2 together with their associating protein 4F2 heavy chain, but the expression of LAT2 in the Saos2 cells was especially weak. JPH203 and BCH, a non-selective L-type amino acid transporter inhibitor, potently inhibited L-leucine uptake in Saos2 cells. As expected, the intrinsic ability of JPH203 to inhibit L-leucine uptake was far more efficient than that of BCH in Saos2 cells. Likewise, JPH203 and BCH inhibited Saos2 cell growth with JPH203 being superior to BCH in this regard. Furthermore, JPH203 increased apoptosis rates and formed DNA ladder in Saos2 cells. Moreover, JPH203 activated the mitochondria-dependent apoptotic signaling pathway by upregulating pro-apoptotic factors, such as Bad, Bax, and Bak, and the active form of caspase-9, and downregulating anti-apoptotic factors, such as Bcl-2 and Bcl-xL. These results suggest that the inhibition of LAT1 activity via JPH203, which may act as a potential novel anti-cancer agent, leads to apoptosis mediated by the mitochondria-dependent intrinsic apoptotic signaling pathway by inducing the intracellular depletion of neutral amino acids essential for cell growth in Saos2 human osteosarcoma cells.