• Korean Journal of Veterinary Service
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• v.35 no.2
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• pp.105-109
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• 2012

Apoptosis is a host defense mechanism that the cell uses to limit production of infectious pathogens. Although many bacteria, viruses and parasites can induce apoptosis in infected cells, some pathogens usually exhibit the ability to suppress the induction of apoptosis in the infected cells. Sophisticated evasion strategies of obligate intracellular parasites, in particular prevention of host cell apoptosis, are necessary to ensure successful replication. To study the ability of Eimeria tenella in this regard, in vitro experiments were performed applying Madin-Darby bovine kidney (MDBK) cells as host cell. We have demonstrated that productive infection of adherent cell lines by E. tenella resulted in an anti-apototic effect. This phenomenon was confirmed using in situ terminal deoxynucleotidyl transferase-mediated (TdT) deoxyuridine triphosphates (dUTP)-fluorescein nick end labeling (TUNEL) assay to detect apoptosis. Therefore, E. tenella could complete its cycle of productive infection while inducing anti-apoptosis in the infected cells. This finding might have implications for the pathobiology of E. tenella and other Eimeria species.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.2
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• pp.77-91
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• 2006

Purpose : To address the ability of Dohaekseungkitang (DST: a commonly used herb formulation in Korea, Japan and China to have anti-cancer effect on cervical carcinoma), we investigated the effects of DST on programmed cell death (apoptosis) in HeLa human cervical carcinoma cells. Methods : We cultured HeLa cell which is human metrocarcinoma cell in D-MEM included 10% fetal bovine serum(Hyclone Laboratories) below $37^{\circ}C$, 5% CO2. Then we observed apoptosis of log phage cell which is changed cultivation liquid 24 Hours periodically. Results : After the treatment of DST for 48 hours, apoptosis occurred in a dose-dependent manner. In this study, we have shown that DST induces calpain and the associated caspase-8 and -9 activations. Apoptosis was prevented by pre-incubation of the cells with the calcium cHeLator-BAPTA-AM, calcium channel blocker-Nif edipine or Ryonidine agonist-Ryonidine peptide, implicating calcium in the apoptotic process. Ubiquitous calpains (mu- and m-calpain) have been repeatedly implicated in apoptosis, especially in calcium-related apoptosis. However this study showed 1hat either calpain inhibitor-calpastin or caspase-3 inhibitor-DEVD- did not blocked the herb formulation-induced apoptosis in HeLa human cervical carcinoma cells. D ST initiates a cell death pathway that is partially dependent of caspases. DST-induced apoptosis requires caspase-independent mechanism. Conclusion : We conclude that DST-induced calpain activation triggers the intrinsic apoptotic pathway in which caspase-independent mechanism is also involved.

• Imaging Science in Dentistry
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• v.30 no.1
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• pp.71-79
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• 2000

Purpose : This study was aimed to evaluate the cell cycle arrest and apoptosis induction after irradiation and epidermal growth factor (EGF) treatment in three human epithelial tumor cell lines (A431, Siha, KB). Materials and Methods: Single irradiation of 2, 5 and 10 Gy was done on three cell lines with 5.38 Gy/min dose rate using Cs-137 irradiator at room temperature. Also, EGF of 10 ng/ml was added immediately after 10 Gy irradiation. Cell growth was evaluated by counting the living cell number using a hemocytometer at 1 day, 2 days, 3 days, 4 days and 5 days after irradiation. Cell cycle arrest and apoptosis induction were assayed with the flow cytometry at 8 hours, 12 hours, 1 day, 2 days, 3 days, 4 days and 5 days after irradiation. Results : Growth of irradiated three cell lines were inhibited in proportion to radiation dose. EGF treatment after irradiation showed various results according to cell lines. On all cell lines, G2 arrest was detected after 8 hours and maximized after 12 hours or 1 day. Amount of G2 arrest was positively dose dependent. However, EGF showed no significant change on G2 arrest. G2 arrest was recovered with time at 2 Gy and 5 Gy irradiation. However, at 10 Gy irradiation, G2 arrest was continued. Apoptosis was detected at 10 Gy irradiation. On EGF treated group after irradiation, A431 and Siha cell lines showed slightly increased apoptosis but there was no statistically significant difference. KB cell line showed no marked change of apoptosis induction. Conclusion : Irradiation effects on cell cycle arrest and apoptosis induction in three human epithelial tumor cell lines, however epidermal growth factor doesn't effect on.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7601-7605
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• 2013

Background: Gambogenic acid is a major active compound of gamboge which exudes from the Garcinia hanburyi tree. Gambogenic acid anti-cancer activity in vitro has been reported in several studies, including an A549 nude mouse model. However, the mechanisms of action remain unclear. Methods: We used nude mouse models to detect the effect of gambogenic acid on breast tumors, analyzing expression of apoptosis-related proteins in vivo by Western blotting. Effects on cell proliferation, apoptosis and apoptosis-related proteins in MDA-MB-231 cells were detected by MTT, flow cytometry and Western blotting. Inhibitors of caspase-3,-8,-9 were also used to detect effects on caspase family members. Results: We found that gambogenic acid suppressed breast tumor growth in vivo, in association with increased expression of Fas and cleaved caspase-3,-8,-9 and bax, as well as decrease in the anti-apoptotic protein bcl-2. Gambogenic acid inhibited cell proliferation and induced cell apoptosis in a concentration-dependent manner. Conclusion: Our observations suggested that Gambogenic acid suppressed breast cancer MDA-MB-231 cell growth by mediating apoptosis through death receptor and mitochondrial pathways in vivo and in vitro.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5189-5193
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• 2016

Objective: Dorema glabrum Fisch. & C.A. Mey is a perennial plant that has several curative properties. Anti-proliferative activity of seeds of this plant has been demonstrated in a mouse fibrosarcoma cell line. The aim of the present study was to evaluate cytotoxicity of D. glabrum root extracts in a human gastric adenocarcinoma (AGS) cell line and explore mechanisms of apoptosis induction, cell cycle arrest and altered gene expression in cancer cells. Materials and Methods: The MTT assay was used to evaluate IC50 values, EB/AO staining to analyze the mode of cell death, and flow cytometry to assess the cell cycle. Quantitative real-time polymerase chain reaction (qRT-PCR) amplification was performed with apoptosis and cell cycle-related gene primers, for cyclin D1, c-myc, survivin, VEGF, Bcl-2, Bax, and caspase-3 to determine alteration of gene expression. Results: Our results showed that n-hexane and chloroform extracts had greatest toxic effects on gastric cancer cells with IC50 values of $6.4{\mu}g/ml$ and $4.6{\mu}g/ml$, respectively, after 72 h. Cell cycle analysis revealed that the population of treated cells in the G1 phase was increased in comparison to controls. Cellular morphological changes indicated induction of apoptosis. In addition, mRNA expression levels of Bax and caspase-3 were increased, and of bcl-2 survivin, VEGF, c-myc and cyclin D1 were decreased. Conclusion: Our study results suggest that D. glabrum has cytotoxic effects on AGS cells, characterized by enhanced apoptosis, reduced cell viability and arrest of cell cycling.

• Environmental Mutagens and Carcinogens
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• v.24 no.3
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• pp.113-120
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• 2004

Chromium compounds are known human and animal carcinogens. In this study, the effects of sodium chromate on apoptosis and cell cycle were investigated in order to unveil the elements of early cellular responses to the metal. Using Chinese hamster ovary cells(CHO-K1-BH4), we found taht chromium (VI) treatment induced apoptosis in these cells, as signified by nuclear fragmentation, DNA laddering on agarose gel electrophoresis, and an increased proportionof cells with hypodiploid DNA. Preceding these changes, chromium (VI) treatment increased caspase 3 pritease activity and also increased expression of p53 protein, while the level of bcl2 protein was not changed. Coincubation with caspase inhibitor, Z-DEVD-FMK, inhibited chromium-induced apoptosis. In the flow cytometric analysis using propidium iodide fluorescence, an increase of cell population in G2/M phase was shown in cells exposed to at least 160 $\mu\textrm{m}$ of sodium chromate for 72h, form 9.8% for 0$\mu\textrm{m}$ chromium (VI) to 26.4% for 320$\mu\textrm{m}$ chromium(VI). Taken together, these findings suggest that chromium(VI)-induced apoptosis is accompanied by G2/M cell cycle arrest, and that p53-mediated pathway may be involved in positive regulation of G2/M arrest and a concurred apoptosis in CHO cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.212-217
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• 2005

The purpose of this study was to examine the effects of Citrus Reticulata(CR) on the Cell Detachment and Apoptosis in Human Gastric Cancer SNU-668 Cells. The effect of CR on apoptosis was investigated through MTT assay, DAPI staining, and TUNEL assay. We also performed RT-PCR for apoptotic genes including BCL-2, BAX, and caspase-3, the caspase-3 activity assay, and western blotting for pro-CASP-3. Then, to detect that adhesion of cell to ECM was reduced by CR, we investigated mRNA expression of CDH1 and PTK2 using RT-PCR, and their protein expressions using western blotting, and immunocytochemistry in SNU-668 cells. In this study, the results showed that treatment of CR induced time and dose-dependent cell death in SNU-668 cells. Downregulated mRNA expression of BCL-2, and upregulated mRNA expressions of BAX and CASP-3 indicated that the cell death was due to apoptosis. Protein expression of inactivated CASP-3, and caspase-3 activity assay also showed that apoptosis was induced in CR-treated cells.

• BMB Reports
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• v.39 no.1
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• pp.97-104
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• 2006

Endostatin is a tumor-derived angiogenesis inhibitor, and the endogenous 20 kDa carboxyl-terminal fragment of collagen XVIII. In addition to inhibiting angiogenesis, endostatin inhibits tumor growth and the induction of apoptosis in several endothelial cell types. However, the mechanisms that regulate endostatin-induced apoptotic cell death are unclear. Here, we investigated apoptotic cell death and the underlying regulatory mechanisms elicited of endostatin in human umbilical vein endothelial cells (HUVECs). Endostatin was found to induce typical apoptotic features, such as, chromatin condensation and DNA fragmentation in these cells. Thus, as the phosphoinositide 3-OH kinase (PI3K)/protein kinase B (PKB) signaling pathway has been shown to prevent apoptosis in various cell types, we investigated whether this pathway could protect cells against endostatin induced apoptosis. It was found that the inhibition of PI3K/PKB significantly increased endostatin-induced apoptosis, and that endostatin-induced cell death is physiologically linked to PKB-mediated cell survival through caspase-8.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3803-3807
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• 2012

Prohibitin (PHB), an evolutionarily-conserved protein, has been found to be over-expressed in gastric cancer and be closely related with tumor malignancy. In this study, to investigate the relationship between PHB expression and cell apoptosis in the BGC823 gastric cancer cell line, low and high expression PHB in BGC823 cells was accomplished using RNA interference technology and gene transfer techniques. Cell proliferation, cell cycling, apoptosis, Bax, Bcl-2 and Cyt.c protein expression and the activation of Caspase-3,9 were assessed after 48h. Over-expression of PHB gene in BGC823 cells resulted in slow cell growth, cell arrest in G2 phase, and an increased apoptosis ratio while the opposite was found for PHB under-expressing cells. In PHB over-expressing cells, the expression of Bax gene was increased, the expression of Bcl-2 was decreased, the activation level of Caspase-3, 9 was increased, but the activation level of Caspase-8 demonstrated no change. These results indicate that PHB induced apoptosis through the mitochondrial pathway.