• Journal of Life Science
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• v.33 no.1
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• pp.102-113
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• 2023

This review discusses the cellular and molecular mechanisms by which the endometrial estrogen and progesterone receptors regulate local estrogen production, expression of the specific estrogen receptors, progesterone resistance, inflammatory responses and the differentiation and survival of endometriotic cells in endometrial inflammation. The epigenetic aberrations of endometrial stromal cells play an important role in the pathogenesis and progression of endometriosis. In particular, differential methylation of the estrogen receptor genes changes in the stromal cells the dominancy of estrogen receptor from ERα into ERβ, and results in the abnormal estrogen responses including inflammation, progesterone resistance and the disturbance of retinoid synthesis. These stromal cells also stimulate local estrogen production in response to PGE2 and the SF-1 mediated induction of steroidogenic enzyme expression, and the increased estradiol then feeds back into the ERβ to repeat the vicious inflammatory cycle through the activation of COX-2. In addition, high levels of ERβ expression may also change the chromatin structure of endometrial mesenchymal stem cells, and together with the repeated menstrual cycles can induce formation of the endometriotic tissue. The cascade of these serial events then leads to cell adhesion, angiogenesis and survival of the differentiation-disregulated stromal cells through the action of inflammatory factors such as ERβ-mediated estrogen, TNF-α and TGF-β1. Therefore, understanding of the dynamic hormonal changes during the menstrual cycle and the corresponding signal transduction mechanisms of the related nuclear receptors in endometrium would provide new insights for treating inflammatory diseases such as the endometriosis.

• Journal of Life Science
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• v.27 no.10
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• pp.1104-1110
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• 2017

SET1A is a histone H3K4 methyltransferase that catalyzes di- and trimethylation of histone H3 at lysine 4 (H3K4). Mono-, di-, and trimethylations on H3K4 (H3K4me1, H3K4me2, and H3K4me3, respectively) are generally correlated with gene activation. Although H3K4 methylation is associated with the stimulation of adipogenesis of 3T3-L1 preadipocytes, it remains unknown whether SET1A plays a role in the regulation of adipogenesis of 3T3-L1 preadipocytes. Here, we investigated whether SET1A regulates 3T3-L1 preadipocytes' adipogenesis and characterized the mechanism involved in this regulation. SET1A expression increased during 3T3-L1 preadipocytes' adipogenesis. Consistent with the increased SET1A expression, the global H3K4me3 level had also increased on day 2 after the induction of adipogenesis in 3T3-L1 adipocytes. SET1A knockdown using siRNA in 3T3-L1 preadipocytes inhibited 3T3-L1 preadipocytes' adipogenesis, as assessed by Oil Red O staining and the expression of adipogenic genes, indicating that SET1A stimulates the adipogenesis of 3T3-L1 preadipocytes. SET1A knockdown inhibited the cell proliferation of 3T3-L1 cells during mitotic clonal expansion (MCE) via down-regulation of the cell cycle gene cyclin E1, as well as the DNA synthesis gene, dihydrofolate reductase. Furthermore, SET1A knockdown repressed peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) expression during the late stage of adipogenesis. These results indicate that SET1A stimulates MCE and $PPAR{\gamma}$ expression, which leads to the promotion of 3T3-L1 preadipocytes' adipogenesis.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.679-686
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• 2003

Purpose : Ataxia telangiectasia mutated(ATM) is involved in DNA damage responses at different cell cycle checkpoints, and signalling pathways associated with regulation of apoptosis in response to ionizing radiation(IR). However, the signaling pathway that underlies IR-induced apoptosis in ATM cells has remained unknown. The purpose of this study was, therefore, to investigate the apoptotic pathway that underlies IR-induced apoptosis in a CT-26 cells expressing dominant negative ATM (DN-ATM). Methods : We generated a replication-deficient recombinant adenovirus encoding the DN-ATM(Ad/DN-ATM) or control adenovirus encoding no transgene(Ad/GFP) and infected adenovirus to CT-26 cells. After infection, we examined apoptosis and apoptotic pathway by [$^3H$]-thymidine assay, DNA fragmentation, and Western immunoblot analysis. Results : DN-ATM gene served as the creation of AT phenotype in a CT-26 cells as revealed by decreased cell proliferations following IR. In addition, IR-induced apoptosis was regulated through the reduced levels of the anti-apoptotic protein Bcl-2, the increased levels of the apoptotic protein Bax, and the activation of caspase-9, caspase-3, and PARP. Conclusion : These results indicate that the pathway of IR-induced apoptosis in CT-26 cells expressing DN-ATM is mediated by mitochondrial signaling pathway involving the activation of caspase 9, caspase 3, and PARP.

• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.67-71
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• 2004

Pata de Vaca (Bauhinia forficata) Is a tree which grows naturally in the rainforests and tropical parts of Peru and Brazil, as well as tropical zones of Asia, eastern Paraguay and northeastern Argentina. The active fraction (Pata-50) of the 70% ethanol extract from Pata de Vaca was sequentially fractionated by HP-20 Diaion column chromatography and C-18 column chromatography, and its characteristics were investigated. The growth of all cancer cells tested except for MCF-7 was Inhibited in a concentration-dependent manner by Pata-50. Its $IC_{50}$ values were estimated to be 40.4 $\mu\textrm{g}$/$m\ell$ on AGS, 51.3 $\mu\textrm{g}$/$m\ell$ on HT-29, 52.1$\mu\textrm{g}$/$m\ell$ on HepG2, 65.2$\mu\textrm{g}$/$m\ell$ on A549, and 77.5$\mu\textrm{g}$/$m\ell$ on HeLa cells. A flow cytometric analysis of HepG2 cells revealed induction of apoptosis, but cell cycle regulation was not affected. The HepG2 cell population of apoptosis region increased In a concentration-dependent manner by Pata-50.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1637-1642
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• 2015

Background: RhoGTPase-activating proteins (RhoGAPs) regulate RhoGTPases in cells, but whether individual reactive oxygen species (ROS) regulate RhoGAPs is unknown. Our previous published papers have shown that deleted in liver cancer 1 (DLC1) inhibits cancer cell migration by its RhoGAP activity. The present study was designed to explore the role of $H_2O_2$ in regulation of DLC1. Materials and Methods: We treated cells with $H_2O_2$ for 24h and phenotypic changes were analyzed by MTT, RT-PCR, Western blotting, immunofluorescence staining and wound healing assays. Results: $H_2O_2$ downregulated cyclin D1 and cyclin E to inhibit proliferation, and upregulated BAX to induce apoptosis in MCF-7 cells. Compared with non-tumorigenic cells, $H_2O_2$ increased expression of DLC1 and reduced activity of RhoA in cancer cells. Stress fiber production and migration were also suppressed by $H_2O_2$ in MDA-MB-231 cells. Conclusions: Our study suggests that $H_2O_2$ inhibits proliferation through modulation of cell cycle and apoptosis-related genes, and inhibits migration by decreasing stress fibers via DLC1/RhoA signaling.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3213-3222
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• 2016

Background: Methyl donor status influences DNA stability and DNA methylation although little is known about effects on DNA methyltransferases. The aim of this study was to determine whether methyl-donor status influences DNA methyltransferase (Dnmt) gene expression in cervical cancer cells, and if so, whether there are associated effects on global DNA methylation. Materials and Methods: The human cervical cancer cell line, C4-II, was grown in complete medium and medium depleted of folate (F-M+) and folate and methionine (F-M-). Growth rate, intracellular folate, intracellular methionine and homocysteine in the extracellular medium were measured to validate the cancer cell model of methyl donor depletion. Dnmt expression was measured by qRT-PCR using relative quantification and global DNA methylation was measured using a flow cytometric method. Results: Intracellular folate and methionine concentrations were significantly reduced after growth in depleted media. Growth rate was also reduced in response to methyl donor depletion. Extracellular homocysteine was raised compared with controls, indicating disturbance to the methyl cycle. Combined folate and methionine depletion led to a significant down-regulation of Dnmt3a and Dnmt3b; this was associated with an 18% reduction in global DNA methylation compared with controls. Effects of folate and methionine depletion on Dnmt3a and 3b expression were reversed by transferring depleted cells to complete medium. Conclusions: Methyl donor status can evidently influence expression of Dnmts in cervical cancer cells, which is associated with DNA global hypomethylation. Effects on Dnmt expression are reversible, suggesting reversible modulating effects of dietary methyl donor intake on gene expression, which may be relevant for cancer progression.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.3
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• pp.193-202
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• 2003

Objective: To evaluate the difference of implantation rate (IR) and clinical pregnancy rate (CPR) between two protocols of endometrial preperation in women undergoing frozen-thawed embryo transfer (FET) cycles. Methods: This study was performed during the different time periods: A retrospective study from January 2000 to June 2001 (phase I) and a prospective study from July 2001 to March 2002 (phase II). All the patients received estradiol valerate (6 mg p.o. daily) starting from day 1 or 2 of the menstrual cycle without pituitary down regulation. Progesterone was administered around day 14 after sonographic confirmation of endometrial thickness $\geq$7 mm and no growing follicle. In Group A (n=88, 99 cycles) of phase I, progesterone was administered i.m. at a dose of 50 mg daily from one day prior to thawing of pronuclear (PN) stage frozen embryo or three days prior to thawing of 6-8 cell stage frozen embryo and then each stage embryos were trasnsferred 2 days or 1 day later after thawing. In Group B (n=246, 299 cycles) of phase I, patients recieved progesterone 100 mg i.m. from one day earlier than group A; two days prior to PN embryo thawing, four days prior to of 6-8 cell embryo thawing. During the phase II, to exclude any differences in embryo transfer procedures, in Group 1 (n=23, 28 cycles) of phase II embryo was transfered by one who have used the progesterone protocol since the phase I. In Group 2 (n=122, 139 cycles) of phase II embryo was transfered by one who use the progesterone protocol from the phase II. Results: When compared across the phase and group, there were no significant differences in the characteristics. During the phase I, there were significant increase in IR (14.4% vs 5.9%, p=0.001) and CPR (28.3% vs 14.5%, p=0.000) in group A. During the phases II, IR (11.8% vs 10.6%) and CPR (27.6% vs 27.3%) show no differences between two groups. Conclusions: In FET cycles, IR and CPR are increased significantly by the change of dosage and timing of progesterone administraton. And the timing is considered to be more important factor because the dosage of progesterone did not affect implantation window in previous studies. Therefore, we suggest that progesterone administration in FET cycle should begin from one day prior to PN stage embryo thawing and three days prior to 6-8 cell stage embryo thawing.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.1
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• pp.71-77
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• 2019

Menadione is known as an anti-tumor factor. Many studies have reported the potential anti-cancer role of menadione against a range of cancer cell lines. In this study, the anti-cancer effects of menadione and the underlying molecular signaling involved in apoptosis was investigated in gastric cancer cell lines. The menadione treatment decreased the cell viability of MKN45 gastric cancer cells. The decreased cell viability was attributed to the induction of apoptosis, which was confirmed by the results indicating the activation of caspase-3 and -7 and the cleavage of PARP in Western blotting. The upstream regulatory molecules involved in apoptosis were investigated further and it was discovered that menadione reduced the expression of survivin, an inhibitor of upstream apoptosis proteins. In addition, a transcription factor ${\beta}$-catenin, which is known to regulate survivin expression, was down-regulated by menadione. A previous report showed that menadione inhibited XIAP expression to induce apoptosis and induced G2/M cell cycle arrest in AGS cells. This study elucidated another inhibitory mechanism of menadione against gastric cancer cells in a different cell line. Although further studies will be needed, the inhibitory mechanism demonstrated in this study will help better understand the anti-cancer effects of menadione.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.485-496
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• 2002

Background : The NF-${\kappa}B$ transcription factors control various biological processes including the immune response, acute phase reaction and cell cycle regulation. NF-${\kappa}B$ complexes are retained in the cytoplasm in the basal state and various stimuli cause a translocation of the NF-${\kappa}B$ complexes into the nucleus where they bind to the ${\kappa}B$ elements and regulate the transcription of the target genes. Recent reports also suggest that NF-${\kappa}B$ proteins are involved in oncogenesis, tumor growth and metastasis. High expression of NF-${\kappa}B$ expression was reported in many cancer cell lines and tissues. The constitutive activation of NF-${\kappa}B$ was also reported in several cancer cell lines supporting its role in cancer development and survival. The anti-apoptotic action of NF-${\kappa}B$ is important for cancer survival. NF-${\kappa}B$ also controls the expression of several proteins that are important for cellular adhesion (ICAM-1, VCAM-1) suggesting a role in cancer metastasis. In lung cancer, high expression levels of the NF-${\kappa}B$ subunit p50 and c-Rel were reported. In fact, high expression does not mean a high activity, and the activation pattern of NF-${\kappa}B$ in lung cancer has not been reported. Materials and Methods : In this study, the NF-${\kappa}B$ nuclear binding activity in the basal and TNF-${\alpha}$ stimulated states were exmined in various lung cancer cell lines and compared with the normal bronchial epithelial cell line. Twelve lung cancer cell lines including the non-small cell and small cell lung cancer cell lines (A549, NCI-H358, NCI-H441, NCI-H552, NCI-H2009, NCI-H460, NCI-H1229, NCI-H1703, NCI-H157, NCI-H187, NCI-H417, NCI-H526) and BEAS-2B bronchial epithelial cell line were used. To evaluate the NF-${\kappa}B$ expression and DNA binding activity, western blot analysis and an electrophoretic mobility shift assay with the nuclear protein extracts. Results : The basal expressions of the p65 and p50 subunits were observed in the BEAS-2B cell line and all lung cancer cell lines except for NCI-H358 and NCI-H460. The expression levels of p65 and p50 were increased 30 minutes after stimulation with TNF-${\alpha}$ in BEAS-2B and in 10 lung cancer cell lines. In the NCI-H358 and NCI-H460 cell lines, p65 expression was not observed in the basal and stimulated states and the two p50 related protein levels were higher after stimulation with TNF-${\alpha}$ These new proteins were smaller than p50 and are thought to be variants of p50. In the basal state, NF-${\kappa}B$ was nearly activated in the BEAS-2B and all lung cancer cell lines. The DNA binding activity of the NF-${\kappa}B$ complexes was markedly higher after stimulation with TNF-${\alpha}$ In the BEAS-2B and all lung cancer cell line except for NCI-H358 and NCI-H460, the activated NF-${\kappa}B$ complex was a p65/p50 heterodimer. In the NCI-H358 and NCI-H460 lung cancer cell lines, the NF-${\kappa}B$ complex was variant of a p50/p50 homodimer. Conclusion : The NF-${\kappa}B$ activation pattern in the lung cancer cell lines and the normal bronchial epithelial cell lines was similar except for the activation of a variant of the p50/p50 homodimer in some lung cancer cell linse.

• Journal of Life Science
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• v.20 no.2
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• pp.281-291
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• 2010

We investigated the antioxidant effects of hederagenin 3-O-b-D-glucopyranosyl($1{\rightarrow}3$)-a-L-rhamnopyranosyl($1{\rightarrow}2$)-a-L-arabinopyranoside (HDL) isolated from root bark of Ulmus davidiana on the activity of enzymes related to reactive oxygen species (ROS) in human osteosarcoma U2OS cells. Cobalt chloride ($CoCl_2$), a transition metal, was used as an inducer of oxidative stress, generating hydrogen peroxide ($H_2O_2$) via increasing xanthine oxidase (XO) activity. The increased levels of $H_2O_2$, XO, ferritin, and ferritin iron by $CoCl_2$ were diminished effectively by co-treatment with HDL in U2OS cells. Furthermore, decreased levels of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) by $CoCl_2$ were highly increased by co-treatment with HDL in U2OS cells; however, the levels of glutathione peroxidase (GPx) did not change. The increased contents of TBARS related to lipid peroxidation were significantly reduced by HDL in U2OS cells. The concentration of GSH changed in a pattern that went against regulated TBARS by $CoCl_2$ and HDL. We examined the expression of p53, $p21^{CIP1/WAF1}$, and $p27^{KIP1}$ proteins related to oxidative stress and cell cycle regulation. As a result, the expression of $p27^{KIP1}$ modulated by $CoCl_2$ was not changed by HDL. However, the expression of p53 and $p21^{CIP1/WAF}$ increased by $CoCl_2$ was reduced by HDL in U2OS cells. Together with alteration of p53 and $p21^{CIP1/WAF1}$ proteins, the accumulated cells at G1 phase by $CoCl_2$ was decreased by HDL in U2OS cells. Our data suggests that HDL inhibits $CoCl_2$-generated ROS in U2OS cells, providing potentially new antioxidant compounds that are isolated from natural products.