• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.87-95
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• 2000

Staphylococcus aureus infections are often life-threatening. Relatively little is known about the host response to these infections, in particular, the implication of apoptosis induced by this microorganism. In this study, we have shown that S. aureus was cytotoxic to J774A.1 cell, a murine macrophage cell line. The cell death mediated by S. aureus occurred through apoptosis, as shown by increase in the proportion of fragmented host cell DNA. Although phagocytosis and NO production had important role in the induction of apoptosis, the contact between bacteria and host cells was not essential for this pathway. A certain bacterial product could also induce typical caspase-dependent apoptosis of J774A.1 cell. It is expected that new interpretation may be possible to host-parasite relationship based on these results.

• Biomolecules & Therapeutics
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• v.29 no.6
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• pp.650-657
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• 2021

Metformin is an anti-diabetic drug and has anticancer effects on various cancers. Several studies have suggested that metformin reduces cell proliferation and stimulates cell-cycle arrest and apoptosis. However, the definitive molecular mechanism of metformin in the pathophysiological signaling in endometrial tumorigenesis and metastasis is not clearly understood. In this study, we examined the effects of metformin on the cell viability and apoptosis of human cervical HeLa and endometrial HEC-1-A and KLE cancer cells. Metformin suppressed cell growth in a dose-dependent manner and dramatically evoked apoptosis in HeLa cervical cancer cells, while apoptotic cell death and growth inhibition were not observed in endometrial (HEC-1-A, KLE) cell lines. Accordingly, the p27 and p21 promoter activities were enhanced while Bcl-2 and IL-6 activities were significantly reduced by metformin treatment. Metformin diminished the phosphorylation of mTOR, p70S6K and 4E-BP1 by accelerating adenosine monophosphate-activated kinase (AMPK) in HeLa cancer cells, but it did not affect other cell lines. To determine why the anti-proliferative effects are observed only in HeLa cells, we examined the expression level of liver kinase B1 (LKB1) since metformin and LKB1 share the same signalling system, and we found that the LKB1 gene is not expressed only in HeLa cancer cells. Consistently, the overexpression of LKB1 in HeLa cancer cells prevented metformin-triggered apoptosis while LKB1 knockdown significantly increased apoptosis in HEC-1-A and KLE cancer cells. Taken together, these findings indicate an underlying biological/physiological molecular function specifically for metformin-triggered apoptosis dependent on the presence of the LKB1 gene in tumorigenesis.

• Journal of Ginseng Research
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• v.45 no.2
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• pp.273-286
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• 2021

Background: Prostate carcinoma is the second most common cancer among men worldwide. Developing new therapeutic approaches and diagnostic biomarkers for prostate cancer (PC) is a significant need. The Chinese herbal medicine Panax quinquefolius saponins (PQS) have been reported to show anti-tumor effects. We hypothesized that PQS exhibits anti-cancer activity in human PC cells and we aimed to search for novel biomarkers allowing early diagnosis of PC. Methods: We used the human PC cell line DU145 and the prostate epithelial cell line PNT2 to perform cell viability assays, flow cytometric analysis of the cell cycle, and FACS-based apoptosis assays. Microarray-based gene expression analysis was used to display specific gene expression patterns and to search for novel biomarkers. Western blot and quantitative real-time PCR were performed to demonstrate the expression levels of multiple cancer-related genes. Results: Our data showed that PQS inhibited the viability of DU145 cells and induced cell cycle arrest at the G1 phase. A significant decrease in DU145 cell invasion and migration were observed after 24 h treatment by PQS. PQS up-regulated the expression levels of p21, p53, TMEM79, ACOXL, ETV5, and SPINT1 while it down-regulated the expression levels of bcl2, STAT3, FANCD2, DRD2, and TMPRSS2. Conclusion: PQS promoted cells apoptosis and inhibited the proliferation of DU145 cells, which suggests that PQS may be effective for treating PC. TMEM79 and ACOXL were expressed significantly higher in PNT2 than in DU145 cells and could be novel biomarker candidates for PC diagnosis.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.2
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• pp.27-37
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• 2008

Purpose: This study was conducted to investigate the effects of Ginseng Radix Alba extract solution on the cell cycle regulation, apoptosis of human uterine myoma cells. Methods: Primary cultured human uterine myoma cells were treated with extract solution of Ginseng Radix Alba concentration of 1, 10 and $100mg/m{\ell}$ for 48 hours. We underwent flow cytometry and western blotting for cell cycle and apoptosis related factors. Results: In flow cytometry, a slight promotion of G1 phase in $1mg/m{\ell}$ group had been observed but, simultaneously a delay of G1 phase in 10 and $100mg/m{\ell}$ groups were also observed. The manifestation of cyclin D1 in Ginseng Radix Alba extract solution medicated group increased compared to the control group. The manifestation of Bax controlling apoptosis increased in terms of concentration but Bcl-2 showed no change. Also VEGF increased in terms of concentration. Conclusion: The present study suggests that Ginseng Radix Alba extract solution treatment in human uterine myoma cells induce the delay of cell cycle and apoptosis. These results suggest that Ginseng Radix Alba will be a promising agent for use in therapeutics agents against human uterine myoma.

• Biomolecules & Therapeutics
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• v.26 no.3
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• pp.328-334
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• 2018

Because of the unsatisfactory treatment options for breast cancer (BC), there is a need to develop novel therapeutic approaches for this malignancy. One such strategy is chemotherapy using non-toxic dietary substances and botanical products. Studies have shown that Panduratin A (PA) possesses many health benefits, including anti-inflammatory, anti-bacterial, anti-oxidant and anticancer activities. In the present study, we provide evidence that PA treatment of MCF-7 BC cells resulted in a time- and dose-dependent inhibition of cell growth with an $IC_{50}$ of $15{\mu}M$ and no to little effect on normal human MCF-10A breast cells. To define the mechanism of these anti-proliferative effects of PA, we determined its effect critical molecular events known to regulate the cell cycle and apoptotic machinery. Immunofluorescence and flow cytometric analysis of Annexin V-FITC staining provided evidence for the induction of apoptosis. PA treatment of BC cells resulted in increased activity/expression of mitochondrial cytochrome C, caspases 7, 8 and 9 with a significant increase in the Bax:Bcl-2 ratio, suggesting the involvement of a mitochondrial-dependent apoptotic pathway. Furthermore, cell cycle analysis using flow cytometry showed that PA treatment of cells resulted in G0/G1 arrest in a dose-dependent manner. Immunoblot analysis data revealed that, in MCF-7 cell lines, PA treatment resulted in the dose-dependent (i) induction of $p21^{WAF1/Cip1}$ and p27Kip1, (ii) downregulation of Cyclin dependent kinase (CDK) 4 and (iii) decrease in cyclin D1. These findings suggest that PA may be an effective therapeutic agent against BC.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.279-286
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• 2020

Purple loosestrife-Lythrum anceps (Koehne) Makino is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in Korea and other Asian traditional medicine. It has been showed pharmacological effects, including anti-oxidant and anti-microbial effects. However, the mechanisms underlying its anti-cancer effect are not yet understood. In this study, we investigated the mechanism of apoptosis signaling pathways by ethanol extract of Lythrum anceps (Koehne) Makino (ELM) in human leukemia U937 cells. Treatment with ELM significantly inhibited cell growth in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies (ApoBDs), DNA fragmentation and increased populations of sub-G1 ratio. Induction of apoptosis by ELM was connected with up-regulation of death receptor (DR) 4 and DR5, pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 protein, and inhibitor of apoptosis protein (IAP) family proteins, depending on dosage. This induction was associated with Bid truncation, mitochondrial dysfunction, proteolytic activation of caspases (-3, -8 and -9) and cleavage of poly(ADP-ribose) polymerase protein. Therefore, our data indicate that ELM suppresses U937 cell growth by activating the intrinsic and extrinsic apoptosis pathways, and thus may have applications as a potential source for an anti-leukemic chemotherapeutic agent.

• The Korea Journal of Herbology
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• v.28 no.6
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• pp.155-160
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• 2013

Objectives : Gastric cancer is a leading cause of cancer-related deaths, worldwide. Houttuynia cordata Thunberg (H. cordata) has been used as a medicinal plants and it has an anti-cancer activity in human colorectal cancer and leukemic cancer. However, the potential anti-cancer activity and mechanisms of H. cordata for human gastric cancer cells have not been tested so far. Thus, this study examined the biological effects of H. cordata on the human gastric cancer cell line SNU-1 and AGS. Methods : Inhibition of cell proliferation and cell cycle by H. cordata was carried out by MTT assay and Muse cell cycle analysis and the expressions of protein associated with apoptosis and cell cycle regulation were investigated with Western blot analysis. Results : In MTT assay, the proliferation of SNU-1 and AGS cells was significantly inhibited by H. cordata in a time and dose dependent manner, Inhibition of cell proliferation by H. cordata was in part associated with apoptotic cell death, as shown by changes in the expression ratio of Bax to Bcl-2 by H. cordata. Also, H. cordata regulated the expression of cell cycle regulatory proteins such as pRb, cyclin D1, cyclin E, CDK4, CDK2, p21 and p15. Conclusion : The antiproliferative effect of H. cordata on SNU-1 and AGS gastric cancer cells revealed in this study suggests that H. cordata has intriguing potential as a chemopreventive or chemotherapeutic agent.

• Journal of Life Science
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• v.18 no.11
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• pp.1513-1520
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• 2008

The 4-Hydroxynonenal (HNE) affects vascular dysfunctions probably through the interruption of the cellular redox balance. To better understand vascular abnormalities resulting from the accumulation of HNE, we delineated mechanism by which mitochondrial apoptosis occurs in the YPEN-1 endothelial cells. HNE treatment led to the loss of mitochondrial membrane potential (${\delta}{\Psi}_m$), resulting in the release of cytochrome c. Data showed decreased Bcl-2 and increased Bax protein levels in HNE-treated cells. NAC, a reactive oxygen species (ROS) scavenger, and penicillamine, the peroxynitrite scavenger, blocked HNE-mediated ROS generation, thereby thwarting the cytochrome c release and apoptosis. The treatment of the cells with zVAD-fmk, a broad range caspase inhibitor did not suppress HNE-induced apoptosis, suggesting that the apoptosis might be the possibility of caspase-independent process. Our findings delineate the underlying mechanism of the HNE induced endothelial apoptosis by triggering depolarization of mitochondria membrane potential that can lead to the deterioration of vasculature homeostasis and subsequent vascular dysfunction with aging.

• The Korea Journal of Herbology
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• v.21 no.1
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• pp.33-42
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• 2006

Objectives : The purpose of this study was to investigate the anticancer effects of Bodusan (BDS) on SNU-1 cells, a human gastric cancer cell line. Methods : To study the cytotoxic effect of BDS on SNU-1 cells, the cells were treated with various concentrations of BDS and then cell viability was determined by XTT reduction method and trypan blue exclusion assay. The typical signs of apoptosis, was examined by western blot analysis. BDS-induced MAPK activation was also examined by Western blot for phosphorylated ERK and p38. Results : BDS reduced proliferation of SNU-1 cells in a dose-dependent manner and decreased procaspase 3 level in a dose-dependent manner and induced the clevage of PARP at concentration > 500 ${\mu}g/ml$. BDS also triggered the mitochondrial apoptotic signaling by increasing the release of cytochrome C from mitochondria to cytosol and reducing the level of anti-apoptotic Bcl-2. BDS significantly decreased ERK phosphorylation and increased p38 phosphorylation in a dose-dependent manner. Futhermore, BDS treatment up-regulated p53 and p21waf expression in a dose-dependent manner. Conclusion : BDS-induced apoptosis is MAP kinase-dependent apoptoric pathway and arrested SNU-1 cells at the G0/G1 of cell cycle. These results suggest that BDS is potentially useful as a chemotherapeutic agent in human gastric cancer.

• Natural Product Sciences
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• v.22 no.3
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• pp.209-215
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• 2016

Kigelia africana (Lam.) Benth. (Bignoniaceae) is a flowering plants in South, Central and West Africa and commonly known as the sausage tree (Eng.); worsboom (Afr.); umVunguta, umFongothi (Zulu); Modukguhlu (North Sotho); Muvevha (Venda). The dried, powdered fruits are used as dressing for wounds and ulcers, haemorrhoids, rheumatism, purgative, skin-firming, lactation in breast-feeding mothers. The aim of this study is to investigate the cytotoxic and apoptotic potentials of 70% ethanolic extracts of Kigelia africana fruits in HCT116 human colon cancer cells. Treatment of Kigelia africana fruits with various concentrations resulted in a sequence of characteristic of apoptosis, including loss of cell viability and morphological changes. Flow cytometry analysis showed Kigelia africana fruits increased the sub-G1 phase (apoptosis) population. Apoptosis confirmed by annexin V-fluorescein isothiocyanate and propidium iodide double staining in HCT116 human colon cancer cell lines. Moreover, analysis of the mechanism indicated that Kigelia africana fruits showed an increased Bax and Bcl-2 expressions in a dose-dependent manner, resulting in activation of hallmarks of apoptotic events, caspase-3, caspase-9 and cleaved poly-ADP-ribose polymerase. This is the first report to demonstrate the cytotoxicity of Kigelia africana fruits on HCT116 human colon cancer cells.