• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.439-445
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• 2006

Purpose : ${\alpha}$-Galactosylceramide (${\alpha}$-GalCer)-stimulated human $V{\alpha}24$ natural killer T (NKT) cells exert antitumor activity against some leukemia in a CD1d dependent and TCR-mediated manner, but could not kill CD1d - negative neuroblastoma (NB) cells. There are few reports about the direct antitumor effect of highly secreted cytokines by these cells on activation. In this study, using a cell-free supernatant (SPN) collected from plate bound hCD1d/${\alpha}$ GalCer tetramers-stimulated NKT cells, we examined whether they could be helpful in the immunotherapeutic treatment of NB. Methods : Cells were cultured in IMDM. The cytokines produced by NKT cells were measured with Cytometric Bead Array (CBA) analysis. Cell viability was evaluated by calcein-AM fluorescence with digital image microscopy scanning (DIMSCAN). The percentage of specific apoptosis was calculated by flow cytometric detection of apoptosis using annexin V and 7-AAD. Results : The activated NKT cells secreted high levels of IL-2, INF-${\gamma}$, TNF-${\alpha}$. The SPN was significantly cytotoxic against four out of eight tested NB cell lines, through mainly apoptosis as evidenced by annexin-V staining and inhibition with the pretreatment of pancaspase blocker. This apoptosis was significantly inhibited when anti-TNF-${\alpha}$ and anti-IFN-${\gamma}$ neutralizing mAbs were used separately and it was completely abolished when the two mAbs were combined. Conclusion : IFN-${\gamma}$ and TNF-${\alpha}$ produced by NKT cells could exert synergistically direct antitumor activity through apoptosis on some NB cell lines.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.22-26
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• 2000

In order to study the cytotoxic properties of sesquitepenes, dehydrocostus lactone (DL) and costunolide from Saussurea lappa, cytotoxicity was measured by SRB method using various human cancer cell lines. Dehydrocostus lactone(DL) and costunolide exhibited significant cytotoxicity against A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT 15 cells. The U937 human leukemia cells treated with DL showed several apoptotic evidences like chromosome condensation and formation of apoptotic bodies. From the results of FACS analysis, early apoptosis was observed by phosphatidylserine externalization detected by annexin V-FITC. Furethermore, these studies determined hypodiploid contents and effects on the cell phase distribution of DL-treated U937 cells. After exposure of U937 cells to $30\mu\textrm{M}$ DL effectively led to G2/M modified cell cycle distribution within 24hr. These observations suggest that DL can be used efficiently for the cancer treatment.

• Journal of Life Science
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• v.26 no.9
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• pp.1015-1021
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• 2016

5-fluorouracil (5-FU), a pyrimidine analog, is a widely used anticancer drug, which works through irreversible inhibition of thymidylate synthase. In the present study, it was investigated the anti-proliferative effects and molecular mechanisms of 5-FU using Ewing's Sarcoma CHP-100 Cells. The present data indicated that treatment of 5-FU to CHP-100 cells induced a G1 phase arrest of the cell cycle in a time-dependent manner. 5-FU-induced G1 arrest was correlated with the accumulation of the hypophosphorylated form of the retinoblastoma protein (pRB) and association of pRB with the transcription factors E2F-1 and E2F-4. Although 5-FU treatment did affect the levels of cyclin-dependent kinases, the levels of cyclin A and B were markedly down-regulated as compared with the untreated control group. In addition, 5-FU-induced G1 arrest of CHP-100 cells was also associated with the induction of apoptosis, as determined by apoptotic cell morphologies, degradation of poly(ADP-ribose) polymerase and Annexin V staining. Furthermore, 5-FU induced the loss of mitochondrial membrane potential with up-regulated pro-apoptotic Bax expression, down-regulated anti-apoptotic Bcl-2 expression and cytochrome c release from mitochondria to cytosol. Collectively, the data suggest that 5-FU is effective in inducing cell growth reduction and apoptosis, in part, by reducing phosphorylation of pRB and activating mitochondrial dysfunction in CHP-100 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6007-6012
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• 2013

ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC-7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and ${\beta}$-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and ${\beta}$-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.

• Journal of Life Science
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• v.21 no.3
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• pp.451-458
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• 2011

Cordycepin (3'-deoxyadenosine), a nucleoside derivative isolated from Cordyceps militaris, is reported to have antitumor effects. However, neither its molecular mechanism nor its molecular targets are well understood. In the present study, molecular mechanisms for the anti-tumor effects of cordycepin were investigated in human prostate cancer PC-3 cells. The MTT assay was used to detect cell viability. Annexin V/FITC assay, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), and $Ca^{2+}$ flux were used to assess for the presence of apoptosis. Western blot analysis was used to detect protein expression. Treatment of cordycepin resulted in significantly decreased cell viability of PC-3 cells in a dose- and time-dependent manner. A dose-dependent apoptotic cell death was also measured by flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in significant mitochondrial dysfunction, ROS production, and elevation of $Ca^{2+}$ concentrations. These phenomena were followed activation of caspase-3, subsequently leading to PARP cleavage and cell apoptosis. Taken together, cordycepin induces apoptosis in PC-3 cells through regulation of a mitochondrial mediated pathway.

• Journal of Life Science
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• v.31 no.11
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• pp.969-979
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• 2021

Type 2 diabetes is a serious chronic metabolic disease, and the goal of diabetes treatment is to keep blood glucose at a normal level and prevent complications from diabetes. Hyperglycemia is a key pathologic feature of type 2 diabetes that mainly results from insulin resistance and pancreatic β-cell dysfunction. Chronic exposure of β-cells to elevated glucose concentrations induces glucotoxicity. In this study, we examined whether an 80% ethanol extract of Oxya chinensis sinuosa Mishchenko (OEE) protected INS-1 pancreatic β-cells against glucotoxicity-induced apoptosis and oxidative stress. Pretreatment with a high concentration of glucose (high glucose = 30 mM) induced glucotoxicity and apoptosis of INS-1 pancreatic β cells. Treatment with OEE significantly increased cell viability. Treatment with 0.01-0.20 mg/ml OEE dose dependently decreased intracellular reactive oxygen species, lipid peroxidation, and nitric oxide levels and increased insulin secretion in high glucose-pretreated INS-1 β cells. OEE also significantly increased the activities of antioxidant enzymes in response to high-glucose-induced oxidative stress. Moreover, OEE treatment significantly reduced the expressions of pro-apoptotic proteins, including Bax, cytochrome C, caspase-3, and caspase-9, and increased anti-apoptotic Bcl-2 expression. Apoptotic cells were identified using Annexin-V/propidium iodide staining, which revealed that treatment with OEE significantly reduced high-glucose-induced apoptosis. These findings implicate OEE as a valuable functional food in protecting pancreatic β-cells against glucotoxicity-induced apoptosis and oxidative stress.

• The Korean Journal of Food And Nutrition
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• v.35 no.3
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• pp.178-184
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• 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
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• v.16 no.2
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• pp.761-767
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• 2015

Background: In this study, we used Daucus carota oil extract (DCOE) to target acute myeloid leukemia (AML) cells. All the AML cell lines tested were sensitive to the extract while peripheral mononuclear cells were not. Analysis of mechanism of cell death showed an increase in cells positive for annexinV and for active caspases, indicating that DCOE induces apoptotic cell death in AML. Inhibition of the MAPK pathway decreased sensitivity of AML cells to DCOE, indicating that cytotoxicity may be dependent on its activity. In conclusion, DCOE induces selective apoptosis in AML cells, possibly through a MAPK-dependent mechanism.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.62-67
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• 2012

TNF-related apoptosis-inducing ligand (TRAIL) is a promising agent for management of cancer because of its selective cytotoxicity to cancer cells. However, some cancer cells have resistance to TRAIL. Accordingly, novel treatment strategies are required to overcome TRAIL resistance. Here, we examined the synergistic apoptotic effect of apigenin in combination with TRAIL in Huh-7 cells. We found that combined treatment of TRAIL and apigenin markedly inhibited Huh-7 cell growth compared to either agent alone by inducing apoptosis. Combined treatment with apigenin and TRAIL induced chromatin condensation and the cleavage of poly (ADP-ribose) polymerase (PARP). In addition, enhanced apoptosis by TRAIL/apigenin combination was quantified by annexin V/PI flow cytometry analysis. Western blot analysis suggested that apigenin sensitizes cells to TRAIL-induced apoptosis by activating both intrinsic and extrinsic apoptotic pathway-related caspases. The augmented apoptotic effect by TRAIL/apigenin combination was accompanied by triggering mitochondria-dependent signaling pathway, as indicated by Bax/Bcl-2 ratio up-regulation. Our results demonstrate that combination of TRAIL and apigenin facilitates apoptosis in Huh-7 cells.

• Journal of Life Science
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• v.27 no.5
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• pp.545-552
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• 2017

Julbernardia globiflora, a tropical African tree widespread in Miombo woodland, has been used in folk medicine for the treatment of depression and stomach problems. However, the antioxidative and anticancer activities of J. globiflora remain unclear. The objective of this study is to evaluate the antioxidative and anticancer effects of methanol extract of J. globiflora (MEJG) and the molecular mechanism of its anticancer activity in human colon carcinoma HT29 cells. MEJG exhibited significant antioxidative effect with an $IC_{50}$ (concentration at 50% inhibition) value of $1.23{\mu}g/ml$ measuring by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and inhibited cell proliferation in a dose-dependent manner in HT29 cells. We found that MEJG induced apoptosis of HT29 cells with the increase of apoptotic cells and apoptotic bodies using Annexin V staining and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. The MEJG treatment showed the increase of Fas, a death receptor, and Bax, a pro-apoptotic protein, and the decrease of Bcl-2, an anti-apoptotic protein, resulting in the release of cytochrome c from the mitochondria into the cytosol and activation of caspase-3, -8 and -9. The apoptotic effects of MEJG were confirmed by cleavage of poly (ADP-ribose) polymerase (PARP). Collectively, these results suggest that MEJG may exert the anticancer effect in HT29 cells by inducing apoptosis via both the intrinsic and extrinsic pathways.