• International Journal of Oral Biology
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• v.35 no.2
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• pp.35-42
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• 2010

The use of bacteria in the treatment of cancer has a long and interesting history. The use of live bacteria in this way however has a number of potential problems including toxicity. Purified low molecular weight bacterial proteins have therefore been tested as anticancer agents to avoid such complications. Oral cancer is a widely occurring disease around the world and these lesions are typically very resistant to anticancer agents. In our present study we investigated the effects of purified recombinant azurin from Pseudomonas (P.) aeruginosa against YD-9 (p53-positive) human oral squamous carcinoma cells. Azurin showed cytotoxic effects against these cells in a dose dependent manner. The cell death accompanied by this treatment was found to be characterized by chromatin condensation and apoptotic bodies. Azurin treatment was further found to increase the expression of p53 The stabilization of p53 and induction of apoptosis in YD-9 cells by azurin suggests that it has potentially very strong anticancer properties in oral squamous carcinoma.

• BMB Reports
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• v.51 no.5
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• pp.219-224
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• 2018

Necroptosis is an emerging form of programmed cell death occurring via active and well-regulated necrosis, distinct from apoptosis morphologically, and biochemically. Necroptosis is mainly unmasked when apoptosis is compromised in response to tumor necrosis factor alpha. Unlike apoptotic cells, which are cleared by macrophages or neighboring cells, necrotic cells release danger signals, triggering inflammation, and exacerbating tissue damage. Evidence increasingly suggests that programmed necrosis is not only associated with pathophysiology of disease, but also induces innate immune response to viral infection. Therefore, necroptotic cell death plays both physiological and pathological roles. Physiologically, necroptosis induce an innate immune response as well as premature assembly of viral particles in cells infected with virus that abrogates host apoptotic machinery. On the other hand, necroptosis per se is detrimental, causing various diseases such as sepsis, neurodegenerative diseases and ischemic reperfusion injury. This review discusses the signaling pathways leading to necroptosis, associated necroptotic proteins with target-specific inhibitors and diseases involved. Several studies currently focus on protective approaches to inhibiting necroptotic cell death. In cancer biology, however, anticancer drug resistance severely hampers the efficacy of chemotherapy based on apoptosis. Pharmacological switch of cell death finds therapeutic application in drug- resistant cancers. Therefore, the possible clinical role of necroptosis in cancer control will be discussed in brief.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1611-1615
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• 2012

Triptolide, a diterpenoid obtained from Tripteryglum wilfordii Hook.f, has attracted interest for its antitumor activities against human tumor cell lines in recent years. This report focuses on anti-proliferative and pro-apoptotic activities in human melanoma A375 cells assessed by CCK8 assay, Hoechst 33258 staining and flow cytometry. In addition, triptolide-induced arrest in the S phase was also observed. Caspase assays showed the apoptosis induced by triptolide was caspase-dependent and probably through intrinsic apoptotic pathways. Furthermore, expression of NF-${\kappa}B$ (p65) and its downstream factors such as Bcl-2, Bcl-$X_L$ was down-regulated. Taken together, the data indicate that triptolide inhibits A375 cells proliferation and induces apoptosis by a caspase-dependent pathway and through a NF-${\kappa}B$-mediated mechanism.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.402-407
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• 1996

Effects of oxidative stress on the induction of apoptosis and the activity of antioxidant enzymes were investigated in HL-60 cells using $H_2O$$_2$and cisplatin which generate oxygen species in the cell. Various concentrations of oxidants were treated to cells and at different incubation time, cells were harvested for assays. Cell viability, morphology by propidium iodide staining and DNA fragmentation by agarose gel electrophoresis were observed to determine whether they induce apoptosis. The activity of antioxidant enzymes such as superoxide dismutase and catalase was also measured to evaluate the cellular response to the oxidative damage. The results are as follows: $H_2O$$_2$ induced apoptosis at 10 $\mu$M after 6h incubation, while it took 12h for cisplatin. Both oxidants induced the superoxide dismutase activity at a tolerable low concentration. However, at a concentration which causes apoptotic cell death, the enzyme level was dropped markedly at first and then recovered to the normal level after which it declined again, probably due to cell death. On the other hand, changes in the activity of catalase were not significant at most concentrations except the statistically significant decrease at 24h after 10 $\mu$M-$H_2O$$_2$treatment. In this study, $H_2O$$_2$- and cisplatintreated cells showed similar results in apoptotic response and enzyme activities, suggesting that anticancer activity of cisplatin may be related, at least in part, to the production of oxygen free radicals.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.730-738
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• 2001

Apoptosis is a morphologically and biochemically distinct form of cell death that occurs in many different cell types in a wide variety of organisms. Ajbizzia julibrissin belonging the family Leguminosae has been used for the treatment of contusion, sore throat, amnesia, and insomnia in oriental traditional medicine. This study investigates whether the water extract off julibrissin induce apoptotic cell death in Jurkat T-acute lymphoblastic leukemia (ALL) cells. Jurkat cells were increased inhibitions of cell viability in a concentration-dependent manner by A julibrissin. This herbal medicine also caused apoptosis as measured by cell morphology and DNA fragmentation. The capability oft julibrissin to induce apoptosis was associated with proteolytic cleavage of specific target protein such as poly (ADP-ribose) polymerase (PARP) protein suggesting the possible involvement of caspases. Our result skewed that Bcl-2 and Bax protein levels were not changed in all A julibrissin-treated groups compared to control group. These results suggest that A julibrissin-mediated apoptosis is independent with Bcl-2 related signaling pathway in this cells.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.37-46
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• 1998

It has been known that $\gamma$-irradiation usually induces cell death in regenerating stem cell in normal tissues like skin, intestine and hematopoietic organ. The experiment were carried out to evaluate the early response of radiation injury in radiosensitive and intermediate radiosensitive tissues in feeding and starving rats with the doses of 3.5 and 7.0 Gy. The results of the study showed that the histological phenomenon was apoptosis in the doses of the radiation as the early response of tissue injury. Apoptosis were showed organ-specific and cellular specific responses suggesting that the selection of apoptosis be exactly focused on highly renewal organs and cells. It was interesting that the rats starved for 72 hours prior to irradiation induced less apoptosis in liver than fed rats. As for cellular responses it appeared that apoptotic cells were mostly distributed in ductal or periportal cells in liver of feeding rats unlikely in liver of Starving rots which showed no difference in zonal distribution. In salivary gland apoptotic cells in fed rats were highly induced in intercalating and ductal cell population than in acinar cell population although unlikely in starved rats. This study showed the value of apoptosis using the detection system of TUNEL for evaluating cellular damage after radiation injury and the diminished effect of starvation on cell damage after ionizing irradiation.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.137-137
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• 2002

Capsaicin has been reported to induce apoptosis in various cancer cells. However, its effect on bladder cancer cells has not been studied. In this study, we investigated whether capsaicin induces apoptosis in murine orthotopic bladder cancer MBT-2 cells and reactive oxydative species(ROS) are involved in capsaicin-induced apoptotic process.(omitted)

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.370-378
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• 2009

N-myc downstream-regulated gene 2 (NDRG2) has recently been found to be a tumor suppressor gene. Although it has been reported that NDRG2 expression in breast cancer cells decreases cell proliferation by inhibiting STAT3 activation via SOCS1 induction, the molecular mechanism of chemotherapeutic agent-induced apoptosis is not well known. To elucidate the effect of NDRG2 on the apoptotic pathway induced by doxorubicin, we established stable cell lines expressing NDRG2 and investigated the effect of NDRG2 expression on the doxorubicin-induced apoptosis. While STAT3 activation was remarkably inhibited by NDRG2 overexpression, the expression level of p21 was increased by NDRG2 expression. We confirmed that NDRG2-expressing cells treated with doxorubicin suppressed STAT3 activation and upregulated p21 expression. NDRG2 expression considerably enhanced TUNEL positive apoptotic cells, poly-ADP ribose polymerase (PARP) cleavage, release of cytochrome c to cytosol, and caspase-3 activity in doxorubicin-induced apoptosis. Bid expression in a resting state and after treatment with doxorubicin increased in MDA-MB-231-NDRG2 cells compared to MDA-MB-231-mock cells. Meanwhile, Bcl-$x_L$ expression decreased in MDA-MB-231-NDRG2 cells compared to MDA-MB-231-mock cells in a resting state and in doxorubicin-treated cells. Collectively, these data suggest that suppression of STAT3 activation by NDRG2 influences the sensitivity to doxorubicin-induced apoptosis of breast cancer cells and this may provide a potential therapeutic benefit to overcome the resistance against doxorubicin in breast cancer.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.149-159
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• 2004

Backgrounds & Objectives : The water extract of Gyungokgo (GOG) has traditionally been used for treatment of general weakness and hemoptysis in oriental medicine. However, little is known about the mechanism by which the water extract of GOG rescues cells from these damages. This study was designed to investigate the protective mechanisms of GOG on H2O2­induced cell death in H9c2 cardiomyoblasts. Methods : In this study, we used H9c2 cells. Cells were treated with oxidative stress in the absence and presence of 1000㎍/ml GOG for 12hrs. Cells were treated with various concentrations of GOG for 12hrs. Cell viability was measured by MTT assay. Oxidative stress, which markedly decreased the viability of H9c2 cells, was characterized by apparent apoptotic features such as chromatin condensation as well as fragmentation of genomic DNA and nuclei. Results : GOG significantly reduced H₂O₂-induced cell death and apoptotic characteristics. The cotreatment of GOG and H₂O₂ in H9c2 cells also induced the phosphorylation of ERKs in a time-dependent manner. Moreover, PD098059, a MEK1 (upstream activator of ERK) inhibitor attenuated the protective effect of GOG on H₂O₂-induced cytotoxicity in H9c2 cardiomyoblast cells. Conclusions : These results suggest that MEK/ERK pathways play important roles in the protective effects of GOG in H9c2 cells. Taken together, they suggest that the protective effects of the water extracts of GOG against oxidative damages may be mediated by the regulation of HO-1, Fas/FasL and Bcl-XS proteins.

• The Journal of Internal Korean Medicine
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• v.35 no.2
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• pp.133-144
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• 2014

O. diffusa, C. appendiculata and F. thunbergii are reported to possess many pharmacological activities including anti-oxidant, anti-inflammatory, anti-hypertension, anti-diabetic and anti-cancer effects. However, their anti-cancer activities in human breast cancer have not been clearly elucidated yet. Objectives: In the present study, we compared the in vitro cytotoxic effects of single and complex treatment of O. diffusa, C. appendiculata and F. thunbergii in human breast cancer MDA-MB-231 cells. Methods: After we treated human breast cancer MDA-MB-231 cells with O. diffusa, C. appendiculata and F. thunbergii. we evaluated viability, growth inhibition, morphological changes, apoptotic body formation, measurement of the cell cycle and formation of DNA fragmentation of these cells. Results: We found that single treatment of O. diffusa and F. thunbergii could inhibit cell proliferation in human breast cancer MDA-MB-231 cells. However, complex treatment of O. diffusa, C. appendiculata and F. thunbergii had weak or no effect on the cell proliferation of MDA-MB-231 cells. The first, anti-proliferative effects of O. diffusa in MDA-MB-231 cells was associated with G2/M arrest of cell cycle and apoptotic cell death. The second, anti-proliferative effect of F. thunbergii in MDA-MB-231 cells was associated with apoptotic cell death. Conclusions: Taken together, these findings suggest that O. diffusa and F. thunbergii may be a potential chemotherapeutic agent for the control of human breast cancer cells, further studies will be needed to identify the molecular mechanisms.