• The Korean Journal of Physiology and Pharmacology
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• v.3 no.1
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• pp.75-82
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• 1999

It has been reported that activation of sphingomyelin pathway and nonsteroidal anti-inflammatory drugs (NSAIDS) inhibit the promotion of colon carcinoma. Ceramide, a metabolite of sphingomyelin, and indomethacin were shown to induce apoptosis in colon carcinoma cells. However, the mechanisms of ceramide- and indomethacin-induced apoptosis in the colon carcinoma cells are not clearly elucidated. Recent studys showed that indomethacin-induced apoptosis in colon cancer cells through the cyclooxygenase-independent pathways, and that may be mediated by generation of ceramide. In this study, we compared effects of ceramide and indomethacin on important modulators of apoptotic processes in HT29 cells, a human colon cancer cell line. Ceramide and indomethacin induced apoptosis dose- and time- dependently. Ceramide and indomethacin increased stress-activated protein kinase (SAPK) activity, and decreased mitogen-activated protein kinase (MAPK) activity. The expression of Bak was increased by the treatment of ceramide and indomethacin. The expression of other Bcl-2 related proteins (Mcl-1, $Bcl-X_L,$ Bax) which were known to be expressed in colon epithelial cells was not changed during the ceramide- and indomethacin-induced apoptosis. Our results suggest that ceramide and indomethacin share common mechanisms for induction of apoptosis in HT29 cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.2
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• pp.199-205
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• 2012

An extract of Alnus japonica (Betulaceae) cortex has been traditionally used for purifying blood, and curing feces containing blood, enteritis, diarrhea, alcoholism and cut wounds. In the present study, we demonstrated that the ethanol extract of Alnus japonica (EAJ) exhibited significantly cytotoxicity in human colon adenocarcinoma HT-29 cells. The results showed that the induction of apoptosis in HT-29 cells by EAJ was characterized by chromatin condensation and activation of caspase-3. EAJ-induced activation of caspase-9 and -3 caused the cleavage of poly ADP-ribose polymerase (PARP) and the release of cytochrome c. The expressions of Bcl-2 and Bid were reduced by EAJ in HT-29 cells, whereas pro-apoptotic protein Bak was increased in the cells. EAJ-induced, dose-dependent induction of apoptosis was accompanied by sustained phosphorylation of MAP kinases (JNK and p38 MAPK), ASK1, and p53. NAC administration, a scavenger of ROS, reversed EAJ-induced cell death. In conclusion, these results indicated that EAJ can cause apoptosis through a ROS-mitochondria-caspases-dependent pathway in human HT-29 cells.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.1
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• pp.69-80
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• 2006

Purpose : This study is to evaluate the synergistic cytotoxicity of Rhizoma Rehmanniae(RR), in adriamycin-treated HeLa human cervical carcinoma cells. Methods : We culture HeLa cell which is human metrocarcinoma cell in D-MEM included 10% fetal bovine serum(Hyclone Laboratories) below $37^{\circ}C$, 5% $CO_2$. Then we observed apoptosis of log phage cell which is changed cultivation liquid 24 Hours periodically. Results : The combination of RR and adriamycin synergistically augmented the cytotoxicity of HeLa cells. The apoptotic cell death was accompanied by the activation of caspase-3 and -8 as well as cleavage of poly(ADP- ribose) polymerase (PARP) in HeLa cells. The co-treatment of RR with adriamycin didn't have any effect on either the expression of Bcl-2 or that of Bax. Interestingly, a synergistic increase in apoptosis by the combination of two drugs was accompanied by the enhancement of Pas and Fas ligand (FasL) expression in HeLa cells. Taken together, the combination of RR and adriamycin significantly augmented the apoptotic cytotoxicity of Fas-positive cells, such as HeLa cells. The pathway is not involved in mitochondria-dependent pathway. Conclusion : RR induces apoptosis in HeLa cells via p38 MAPK activation.

• Applied Biological Chemistry
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• v.51 no.2
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• pp.129-135
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• 2008

Berberine is an isoquinoline alkaloid used in traditional Chinese medicine and has been isolated from a variety of plants, such as Coptis chinensis and Phellodendron amurense. It has a wide spectrum of clinical applications such as in anti-tumor, anti-microbial, and anti-inflammatory activities. However, it is still unknown that berberine related with reactive oxygen species (ROS)-mediated apoptosis pathway in human hepatoma HepG2 cells. In the present study, we are examined the molecular mechanism of ROS- and p38 MAP kinase-mediated apoptosis by berberine in HepG2 cells. Berberine increased cytotoxicity effects by time- and does-dependent manner. $LD_{50}$ was detected 50 ${\mu}M$ at 48h of exposure to berberine. Nuclei cleavage and apoptotic DNA fragmentation were observed in cells treated with 50 ${\mu}M$ of berberine for 48h. Moreover, berberine induced the activating of caspase-3, p53, p38 and Bax expression, whereas the expression of anti-apoptotic signaling pathways, Bcl-2, was decreased. Additionally, berberine-treated cells had an increased level of generation of ROS and nitric oxide (NO). These results indicated that berberine induces apoptosis of HepG2 cells may be mediated oxidative injury acts as an early and upstream change, triggers mitochondrial dysfunction, Bcl-2 and Bax modulation, p38 and p53 activation, caspase-3 activation, and consequent leading to apoptosis.

• Molecules and Cells
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• v.24 no.1
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• pp.95-104
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• 2007

The mechanism of acacetin-induced apoptosis of human breast cancer MCF-7 cells was investigated. Acacetin caused 50% growth inhibition ($IC_{50}$) of MCF-7 cells at $26.4{\pm}0.7{\mu}M$ over 24 h in the MTT assay. Apoptosis was characterized by DNA fragmentation and an increase of sub-G1 cells and involved activation of caspase-7 and PARP (poly-ADP-ribose polymerase). Maximum caspase 7 activity was observed with $100{\mu}M$ acacetin for 24 h. Caspase 8 and 9 activation cascades mediated the activation of caspase 7. Acacetin caused a reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c and apoptosis inducing factor (AIF) into the cytoplasm, enhancing ROS generation and subsequently resulting in apoptosis. Pretreatment of cells with N-acetylcysteine (NAC) reduced ROS generation and cell growth inhibition, and pretreatment with NAC or a caspase 8 inhibitor (Z-IETD-FMK) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c and AIF. Stress-activated protein kinase/c-Jun $NH_4$-terminal kinase 1/2 (SAPK/JNK1/2) and c-Jun were activated by acacetin but extracellular-regulated kinase 1/2 (Erk1/2) nor p38 mitogen-activated protein kinase (MAPK) were not. Our results show that acacetin-induced apoptosis of MCF-7 cells is mediated by caspase activation cascades, ROS generation, mitochondria-mediated cell death signaling and the SAPK/JNK1/2-c-Jun signaling pathway, activated by acacetin-induced ROS generation.

• Journal of Life Science
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• v.26 no.1
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• pp.101-108
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• 2016

The aim of this study was to evaluate the relationships between the expression of Heat shock protein70 (HSP70), Raf-1 and Bcl-2-associated athanogene-1 (BAG1) protein in diffuse type gastric carcinoma and examine association of HSP70, Raf-1 and BAG1 expression with various clinic-pathological factors and survival. Heat shock protein70 is induced in the cells in response to various stress conditions, including carcinogens. Overexpression of heat shock protein 70 has been observed in many types of cancer. The proto-oncoprotein Raf is pivotal for mitogen-activated protein kinase (MAPK) signaling, and its aberrant activation has been implicated in multiple human cancers. Overexpression of BAG1 protein has been documented in some type of human cancer. BAG1 has been reported to interact with protein involved with a variety of signal pathway, and regulation of cell differentiation, survival and apoptosis. These interaction partners include HSP70 and Raf-1. The percentage of tumors exhibiting HSP70 positivity was significantly in cases of positive lymph node metastasis (64.9%) compared to cases without lymph node metastasis (35.1%, p=0.007). HS70 expression was correlated with pathological N-stage (p=0.006). Expression of BAG1 was detected in the majority of diffuse type gastric carcinoma tissues (71.7%), especially in younger patients (80% vs 52.6%, p=0.035). Furthermore BAG1 expression was correlated with tumor size (p=0.020). Raf-1 expression was found to be significantly associated with tumor size (p=0.005). The result indicate that HSP70 was significantly correlated the progression of diffuse type gastric cancer. Expression of BAG1 and Raf-1 may be used as diagnostic markers for gastric carcinoma.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.495-501
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• 2019

Aloin [1,8-Dihydroxy-10-(${\beta}$-D-glucopyranosyl)-3-(hydroxymethyl)-9(10H)-anthracenone], is a natural anthraquinone from aloe. It has been shown to have antioxidant and anticancer effects in various types of human cancer cells, but the anticancer effects of aloin in human colorectal cancer cells HT-29 have not been elucidated. In this study, possible mechanisms by which aloin exerts its apoptotic action in cultured human colorectal cancer HT-29 cells were investigated. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that treatment with aloin (0, 100, 200, 300 and $400{\mu}M$) reduced cell viability in a concentration-dependent manner in HT-29 and showed no effects on cell proliferation in A375SM and AGS cells. In addition, it was confirmed that apoptotic body was significantly increased as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, and increased apoptosis rate by flow cytometry in HT-29 cells treated with aloin (0, 200 and $400{\mu}M$). We confirmed by western blotting that aloin activated Bax (pro-apoptotic), cleaved-poly (ADP-ribose) polymerase (PARP) and caspase-3, -8 and Bcl-2 (anti-apoptotic) were not changed compared with the control. Aloin induced up-regulation of phospho-p38 and down-regulation of phospho-extracellular signal-regulated kinase (ERK)1/2. Therefore, aloin suppressed the growth inhibitory effects by the induction of apoptosis in human colorectal cancer cells and has potential as a cancer preventive medicine.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.217-225
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• 2021

This study aimed to investigate the neuroprotective effects of 1-methoxylespeflorin G11 (MLG), a pterocarpan, against glutamate-induced neurotoxicity in neuronal HT22 hippocampal cells. The protective effects of MLG were evaluated using MTT assay and microscopic analysis. The extent of apoptosis was studied using flow cytometric analysis performed on the damaged cells probed with annexin V/propidium iodide. Moreover, mitochondrial reactive oxygen species (ROS) were assessed using flow cytometry through MitoSOXTM Red staining. To determine mitochondrial membrane potential, staining with tetramethylrhodamine and JC-1 was performed followed by flow cytometry. The results demonstrated that MLG attenuates glutamate-induced apoptosis in HT22 cells by inhibiting intracellular ROS generation and mitochondrial dysfunction. Additionally, MLG prevented glutamate-induced apoptotic pathway in HT22 cells through upregulation of Bcl-2 and downregulation of cleaved PARP-1, AIF, and phosphorylated MAPK cascades. In addition, MLG treatment induced HO-1 expression in HT22 cells. These results suggested that MLG exhibits neuroprotective effects against glutamate-induced neurotoxicity in neuronal HT22 cells by inhibiting oxidative stress and apoptosis.

• Journal of Life Science
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• v.17 no.10
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• pp.1447-1451
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• 2007

Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.