• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4519-4525
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• 2014

Oleanolic acid (OA) is a nutritional component widely distributed in various vegetables. Although it has been well recognized for decades that OA exerts certain anti-tumor activity by inducing mitochondria-dependent apoptosis, it is still unclear that what molecular signaling is responsible for this effect. In this study, we employed cancer cell lines, A549, BXPC-3, PANC-1 and U2OS to elucidate the molecular mechanisms underlying OA anti-tumor activity. We found that activation of MAPK pathways, including p-38 MAPK, JNK and ERK, was triggered by OA in both a dose and time-dependent fashion in all the tested cancer cells. Activation was accompanied by cleavage of caspases and PARP as well as cytochrome C release. SB203580 (p38 MAPK inhibitor), but not SP600125 (JNK inhibitor) and U0126 (ERK inhibitor), rescued the pro-apoptotic effect of OA on A549 and BXPC-3 cells. OA induced p38 MAPK activation promoted mitochondrial translocation of Bax and Bim, and inhibited Bcl-2 function by enhancing their phosphorylation. OA can induce reactive oxygen species (ROS)-dependent ASK1 activation, and this event was indispensable for p38 MAPK-dependent apoptosis in cancer cells. In vivo, p38 MAPK knockdown A549 tumors proved resistant to the growth-inhibitory effect of OA. Collectively, we elucidated that activation of ROS/ASK1/p38 MAPK pathways is responsible for the apoptosis stimulated by OA in cancer cells. Our finding can contribute to a better understanding of molecular mechanisms underlying the antitumor activity of nutritional components.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.69-79
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• 2020

Aging is one of the risk factors for the development of cardiovascular diseases. During the progression of cellular senescence, cells enter a state of irreversible growth arrest and display resistance to apoptosis. As a flavonoid, quercetin induces apoptosis in various cells. Accordingly, we investigated the relationship between quercetin-induced apoptosis and the inhibition of cellular senescence, and determined the mechanism of oxidative stress-induced vascular smooth muscle cell (VSMC) senescence. In cultured VSMCs, hydrogen peroxide (H₂O₂) dose-dependently induced senescence, which was associated with increased numbers of senescence-associated β-galactosidase-positive cells, decreased expression of SMP30, and activation of p53-p21 and p16 pathways. Along with senescence, expression of the anti-apoptotic protein Bcl-2 was observed to increase and the levels of proteins related to the apoptosis pathway were observed to decrease. Quercetin induced apoptosis through the activation of AMP-activated protein kinase. This action led to the alleviation of oxidative stress-induced VSMC senescence. Furthermore, the inhibition of AMPK activation with compound C and siRNA inhibited apoptosis and aggravated VSMC senescence by reversing p53-p21 and p16 pathways. These results suggest that senescent VSMCs are resistant to apoptosis and quercetin-induced apoptosis attenuated the oxidative stress-induced senescence through activation of AMPK. Therefore, induction of apoptosis by polyphenols such as quercetin may be worthy of attention for its anti-aging effects.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7501-7508
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• 2013

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder of hematopoietic stem cell scarrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL1 fusion gene. The tyrosine kinase inhibitor (TKI) of BCR-ABL1 kinase is a treatment of choice for control of CML. Objective: Recent studies have demonstrated that miRNAs within exosomes from cancer cells play crucial roles in initiation and progression. This study was performed to assess miRNAs within exosomes of K562 cells. Methods: miRNA microarray analysis of K562 cells and K562 cell-derived exosomes was conducted with the 6th generation miRCURYTM LNA Array (v.16.0). Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also carried out. GO terms and signaling pathways were categorized into 66 classes (including homophilic cell adhesion, negative regulation of apoptotic process, cell adhesion) and 26 signaling pathways (such as Wnt). Results: In exosomes, 49 miRNAs were up regulated as compared to K562 cells, and two of them were further confirmed by quantitative real-time PCR. There are differentially expressed miRNAs between K562 cell derived-exosomes and K562 cells. Conclusion: Selectively expressed miRNAs in exosomes may promote the development of CML via effects on interactions (e.g. adhesion) of CML cells with their microenvironment.

• Molecules and Cells
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• v.39 no.2
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• pp.119-128
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• 2016

Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-$3{\beta}$ activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.

• Journal of Biomedical Engineering Research
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• v.42 no.1
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• pp.18-24
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• 2021

Vibration is a mechanical cue that can be applied to adipose tissues for the purpose of treating obesity. However, the exact correlation between vibration and other anti-adipogenic pathways, such as development of cytoskeleton and apoptosis, remains unknown. The objective of this study was to investigate the unknown anti-adipogenic effects of vibration with varied frequencies on preadipocytes. 3T3-L1 preadipocytes were cultured in Dulbecco's modified Eagle's medium (DMEM) containing 5% calf serum at 37 ℃ with 5% CO2 in a humidified incubator. Vibration was generated using Arduino Uno microcontroller and vibration motor module with 1 V DC, and applied to preadipocytes for 3 days. Frequency conditions were set to 20, 55, and 90 Hz. Then, the expressions of p38 pathway, ROCK-1, α-actinin, Bax, Bcl-2, caspase-9, 8, and 3 were analyzed with western blot. As a result, p38 pathway was inhibited in 55 and 90 Hz while ROCK-1 and α-actinin were expressed in 20 Hz. Caspase-3, a terminal apoptotic factor, was activated in 20 Hz via extrinsic pathway rather than intrinsic pathway. Results suggest that various frequencies of vibration can inhibit adipogenesis via different pathways which sheds light on future mechanotransduction applications of vibration for the treatment of obesity.

• Herbal Formula Science
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• v.32 no.1
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• pp.39-49
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• 2024

Objectives : The purpose of this study was to investigate the molecular targets and pathways of anti-inflammatory effects of Jakyakgamchotang with corydalis tuber (JC) using network pharmacology. Methods : The compounds in constituent herbal medicines of JC were searched in TCM systems pharmacology (TCMSP). Target gene informations of the components were collected using chemical-target interactions database provided by Pubchem. Afterwards, network analysis between compounds and inflammation-related target genes was performed using cytoscape. Go enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on inflammation-related targets using DAVID database. Results : 70 active compounds related to inflammation were identified, and 295 target genes related to the anti-inflammatory activity of the compound of JC were identified. In the Go biological process DB and KEGG pathway DB, "inflammatory response", "cellular response to lipopolysaccharide", "positive regulation of interleukin-6 production", and "positive regulation of protein kinase B. signaling", "positive regulation of ERK1 and ERK2 cascade", "positive regulation of I-kappaB kinase/NF-kappaB signaling", "negative regulation of apoptotic process", and "PI3K-Akt signaling pathway" were found to be mechanisms related to the anti-inflammatory effects related to the target genes of JC. The main compounds predicted to be involved in the anti-inflammatory effect of JC were quercetin, licochalcone B, (+)-catechin, kaempferol, and emodin. Conclusions : This study provides the molecular targets and potential pathways of JC on inflammation. It can be used as a basic data for using JC for various inflammatory disease in traditional korean medicine clinic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1257-1264
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• 2016

Extracts from Artemisia annua $Linn\acute{e}$ (AAE) have various functions (anti-malaria, anti-virus, and anti-oxidant). However, the mechanism of the effects of AAE is not well known. Thus, we determined the apoptotic effects of AAE in AGS human gastric carcinoma cells. In this study, we suggested that AAE may exert cancer cell apoptosis through the Akt/mammalian target of rapamycin (mTOR)/glycogen synthase kinase (GSK)-$3{\beta}$ signal pathway and mitochondria-mediated apoptotic proteins. Activation by Akt phosphorylation resulted in cell proliferation through phosphorylation of tuberous sclerosis complex 2 (TSC2), mTOR, and GSK-$3{\beta}$. Thus, de-phosphorylation of Akt inhibited cell proliferation and induced apoptosis through inhibition of Akt, mTOR, phosphorylation of GSK-$3{\beta}$ at serine9, and control of Bcl-2 family members. Inhibition of GSK-$3{\beta}$ attenuated loss of mitochondrial membrane potential and release of cytochrome C. Bax and pro-apoptotic proteins were activated by their translocation into mitochondria from the cytosol. Translocation of Bax induced outer membrane transmission and generated apoptosis through cytochrome C release and caspase activity. We also measured 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, lactate dehydrogenase assay, Hoechst 33342 staining, Annexin V-PI staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide staining, and Western blotting. Accordingly, our study showed that AAE treatment to AGS cells resulted in inhibition of Akt, TSC2, GSK-$3{\beta}$-phosphorylated, Bim, Bcl-2, and pro-caspase 3 as well as activation of Bax and Bak expression. These results indicate that AAE induced apoptosis via a mitochondrial event through regulation of the Akt/mTOR/GSK-$3{\beta}$ signaling pathways.

• Journal of Life Science
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• v.26 no.6
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• pp.663-672
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• 2016

The Cnidium monnieri (L.) Cusson is an annual plant distributed in China and Korea. The fruit of C. monnieri is used as a medicinal herb that is effective for the treatment of carbuncle and pain in female genitalia. However, the anti-cancer effects of CME have not yet been reported. In this study, we assessed the apoptotic effects and cell cycle arrest effects of ethanol extracts from C. monnieri on HCT116 colon cancer cells. The results of an MTT assay and LDH assay demonstrated a decrease in cell viability and the cytotoxic effects of CME. In addition, the number of apoptotic body and the apoptotic rate were increased in a dose-dependent manner through Hoechst 33342 staining and Annexin V-PI double staining. In addition, cell cycle arrest occurred at the G1 phase by CME. Protein kinase B (Akt) plays an important role in cancer cell survival, growth, and division. Akt down-regulates apoptosis-mediated proteins, such as mammalian target of rapamycin (mTOR), p53, and Glycogen Synthase kinase-3β (GSK-3β). CME could regulate the expression levels of p-Akt, p-mTOR, p-GSK-3β, Bcl-2 family members, caspase-3, and PARP. Furthermore, treatment with CME, LY294002 (PI3K/Akt inhibitor), BIO (GSK-3β inhibitor), and Rapamycin (mTOR inhibitor) showed that apoptotic effects occurred through the regulation of the AKT/mTOR/GSK-3β signaling pathway. Our results demonstrated CME could induce apoptosis and cell cycle arrest in HCT116 colon cancer cells.

• Journal of Life Science
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• v.25 no.8
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• pp.947-952
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• 2015

Prostate apoptosis response-4 (Par-4) was originally identified in androgen-independent prostate cancer cells undergoing apoptosis. Par-4 is ubiquitously expressed in normal cells and tissues, but it is downregulated in several types of cancers. Par-4 is a 38 kDa tumor suppressor protein encoded by the PARW gene. Par-4 promotes apoptosis in a variety of cancerous cells, but not in normal cells. In this review, we focused on the structure, expression and function of Par-4 in apoptotic signaling pathway. Functional domains of Par-4 include two nuclear localization sequences (NLS), a leucine zipper (LZ) domain, a nuclear export sequence (NES) and selective for apoptosis in cancer cell (SAC) domain. Many studies have underlined the importance of Par-4 in preventing cancer development. The activity of Par-4 is differently regulated by localization of intracellular and extracellular Par-4. Intracellular Par-4 inhibits Akt- and NF-κB-mediated cell survival pathways and downregulates Bcl-2 expression. Extracellular Par-4 activates the extrinsic apoptotic pathway by binding to cell surface receptor GRP78, a stress response protein that is in the endoplasmic reticulum (ER). Endogenous Par-4 sensitizes cancer cells to various apoptotic stimuli, while exogenous Par-4 enhances SAC domain-dependent apoptosis in cancer cells, but not normal cells. Therefore, Par-4 is an attractive target for cancer therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3939-3944
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• 2014

Background: To elucidate the role of rapamycin and PF4 on apoptosis regulation via Bax (pro-apoptosis), Bcl-2 (anti-apoptosis) and survivin activation on the growth in the 1-methyl-1-nitrosourea-induced invasive breast carcinoma model. Materials and Methods: Thirty five female Sprague Dawley rats at age 21-day old were divided into 4 groups; Group 1 (control, n=10), Group 2 (PF4, n=5), Group 3 (rapamycin, n=10) and Group 4 (rapamycin+PF4, n=10). MNU was administered intraperitionally, dosed at 70mg/kg body weight. The rats were treated when the tumors reached the size of $14.5{\pm}0.5mm$ and subsequently sacrificed after 5 days. Rapamycin and PF4 were administered as focal intralesional injections at the dose of $20{\mu}g$/lesion. The tumor tissue was then subjected to histopathological examinations for morphological appraisal and immunohistochemical assessment of the pro-apoptotic marker, Bax and anti-apoptotic markers, Bcl-2 and survivin. Results: The histopathological pattern of the untreated control cohort showed that the severity of the malignancy augments with mammary tumor growth. Tumors developing in untreated groups were more aggressive whilst those in treated groups demonstrated a transformation to a less aggressive subtype. Combined treatment resulted in a significant reduction of tumor size without phenotypic changes. Bax, the pro-apoptotic marker, was significantly expressed at higher levels in the rapamycin-treated and rapamycin+PF4-treated groups compared to controls (p<0.05). Consequently, survivin was also significantly downregulated in the rapamycin-treated and rapamycin+PF4-treated group and this was significantly different when compared to controls (p). Conclusions: In our rat model, it could be clearly shown that rapamycin specifically affects Bax and survivin signaling pathways in activation of apoptosis. We conclude that rapamycin plays a critical role in the induction of apoptosis in MNU-induced mammary carcinoma.