• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.402-410
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• 2010

Although the overproduction of prostaglandin $E_2$ ($PGE_2$) in intestinal epithelial cells has been considered to be highly correlated with the colorectal carcinogenesis, the precise mechanism of action remains poorly elucidated. Accumulating evidence suggests that the PGE receptor (EP)-mediated signal transduction pathway might play an important role in this process. In the present study, we investigated the mechanism of action underlying $PGE_2$-mediated cell proliferation and the effect of resveratrol on the proliferation of human colon cancer cells in terms of the modulating $PGE_2$-mediated signaling pathway. $PGE_2$ stimulated the proliferation of several human colon cancer cells and activated growth-stimulatory signal transduction, including Akt and ERK. $PGE_2$ also increased the phosphorylation of GSK-$3{\beta}$, the translocation of ${\beta}$-catenin into the nucleus, and the expressions of c-myc and cyclin D1. Resveratrol, a cancer chemopreventive phytochemical, however, inhibited $PGE_2$-induced growth stimulation and also suppressed $PGE_2$-mediated signal transduction, as well as ${\beta}$-catenin/T cell factor-mediated transcription in human colon cancer cells. These findings present an additional mechanism through which resveratrol affects the regulation of human colon cancer cell growth.

• Journal of Pharmacopuncture
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• v.24 no.2
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• pp.68-75
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• 2021

Objectives: The hair follicle is composed of more than 20 kinds of cells, and mesoderm derived dermal papilla cells and keratinocytes cooperatively contribute hair growth via Wnt/β-catenin signaling pathway. We are to investigate β-catenin expression and regulatory mechanism by CBD in alopecia hair tissues and dermal papilla cells. Methods: We performed structural and anatomical analyses on alopecia patients derived hair tissues using microscopes. Pharmacological effect of CBD was evaluated by β-catenin expression using RT-PCR and immunostaining experiment. Results: Morphological deformation and loss of cell numbers in hair shaft were observed in alopecia hair tissues. IHC experiment showed that loss of β-catenin expression was shown in inner shaft of the alopecia hair tissues, indicating that β-catenin expression is a key regulatory function during alopecia progression. Consistently, β-catenin expression was decreased in testosterone or PMA treated dermal papilla cells, suggesting that those treatments are referred as a model on molecular mechanism of alopecia using dermal papilla cells. RT-PCR and immunostaining experiments showed that β-catenin expression was decreased in RNA level, as well as decreased β-catenin protein might be resulted from ubiquitination. However, CBD treatment has no changes in gene expression including β-catenin, but the decreased β-catenin expression by testosterone or PMA was restored by CBD pretreatment, suggesting that potential regulatory effect on alopecia induction of testosterone and PMA. Conclusion: CBD might have a modulating function on alopecia caused by hormonal or excess of signaling pathway, and be a promising application for on alopecia treatment.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.213-217
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• 2013

Enterotoxigenic Bacteroides fragilis (ETBF) is a human gut commensal bacteria that causes inflammatory diarrhea and colitis. ETBF also promotes colorectal tumorigenesis in the Min mouse model. The key virulence factor is a secreted metalloprotease called B. fragilis toxin (BFT). BFT induces E-cadherin cleavage, cell rounding, activation of the ${\beta}$-catenin pathway and secretion of IL-8 in colonic epithelial cells. However, the precise mechanism by which these processes occur and how these processes are interrelated is still unclear. E-cadherin form homophilic interactions which tethers adjacent cells. Loss of E-cadherin results in detachment of adjacent cells. Prior studies have suggested that BFT induces IL-8 expression by inducing E-cadherin cleavage; cells that do not express E-cadherin do not secrete IL-8 in response to BFT. In the current study, we found that HT29/C1cells treated with dilute trypsin solution induced E-cadherin degradation and IL-8 secretion, consistent with the hypothesis that E-cadherin cleavage causes IL-8 secretion. However, physical damage to the cell monolayer did not induce IL-8 secretion. We also show that EDTA-mediated disruption of E-cadherin interactions without E-cadherin degradation was sufficient to induce IL-8 secretion. Finally, we determined that HT29/C1 cells treated with LiCl (${\beta}$-catenin activator) induced IL-8 secretion in a dose-dependent and time-dependent manner. Taken together, our results suggest that BFT induced IL-8 secretion may occur by the following process: E-cadherin cleavage, disruption of cellular interactions, activation of the ${\beta}$-catenin pathway and IL-8 expression. However, we further propose that E-cadherin cleavage per se may not be required for BFT induced IL-8 secretion.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5935-5939
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• 2013

Our study is to determine the presence of endometrial intraepithelial neoplasia (EIN) in endometrial biopsy specimens classified by the 1994 World Health Organization (WHO) criteria for endometrial hyperplasia. Endometrial biopsy specimens that were stained with hematoxylin and eosin (HE) were examined and categorized by the WHO 1994 criteria and for the presence of EIN as defined by the International Endometrial Collaborative Group. ${\beta}$-catenin expression was examined by immunohistochemistry. A total of 474 cases of HE stained endometrial biopsy tissues were reviewed. There were 379 cases of simple endometrial hyperplasia, 16 with simple atypical endometrial hyperplasia, 48 with complex endometrial hyperplasia, and 31 with complex atypical endometrial hyperplasia. Among the 474 endometrial hyperplasia cases, there were 46 (9.7%) that were classified as EIN. Of these 46 cases, 11(2.9%) were classified as simple endometrial hyperplasia, 1 (6.3%) as simple atypical endometrial hyperplasia, 6 (12.5%) as complex endometrial hyperplasia, and 28 (90.3%) as complex atypical endometrial hyperplasia. EIN was associated with a higher rate of ${\beta}$-catenin positivity than endometrium classified as benign hyperplasia (72% vs. 22.5%, respectively, P<0.001), but a lower rate than endometrial adenocarcinoma (72% vs. 96.2%, respectively, P<0.001). In benign endometrial hyperplasia, high ${\beta}$-catenin expression was noted in the cell membranes, whereas in EIN and endometrial adenocarcinoma high expression was noted in the cytoplasm. In conclusion, EIN is more accurate than the WHO classification for the diagnosis of precancerous lesions of the endometrium.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.448-458
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• 2020

We investigated the therapeutic effects of microRNA-139-5p in relation to osteoporosis of bone marrow-derived mesenchymal stem cell (BMSCs) and its underlying mechanisms. In this study we used a dexamethasone-induced in vivo model of osteoporosis and BMSCs were used for the in vitro model. Real-time quantitative polymerase chain reaction (RT-PCR) and gene chip were used to analyze the expression of microRNA-139-5p. In an osteoporosis rat model, the expression of microRNA-139-5p was increased, compared with normal group. Down-regulation of microRNA-139-5p promotes cell proliferation and osteogenic differentiation in BMSCs. Especially, up-regulation of microRNA-139-5p reduced cell proliferation and osteogenic differentiation in BMSCs. Overexpression of miR-139-5p induced Wnt/β-catenin and down-regulated NOTCH1 signaling in BMSCs. Down-regulation of miR-139-5p suppressed Wnt/β-catenin and induced NOTCH1 signaling in BMSCs. The inhibition of NOTCH1 reduced the effects of anti-miR-139-5p on cell proliferation and osteogenic differentiation in BMSCs. Activation of Wnt/β-catenin also inhibited the effects of anti-miR-139-5p on cell proliferation and osteogenic differentiation in BMSCs. Taken together, our results suggested that the inhibition of microRNA-139-5p promotes osteogenic differentiation of BMSCs via targeting Wnt/β-catenin signaling pathway by NOTCH1.

• BMB Reports
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• v.47 no.10
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• pp.552-557
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• 2014

The main purpose of this study was to investigate whether type 3 muscarinic acetylcholine receptor (M3R) dysfunction induced vascular hyperpermeability. Transwell system analysis showed that M3R inhibition by selective antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and small interfering RNA both increased endothelial permeability. Using coimmunoprecipitation and Western blot assay, we found that M3R inhibition increased VE-cadherin and ${\beta}$-catenin tyrosine phosphorylation without affecting their expression. Using PTP1B siRNA, we found that PTP1B was required for maintaining VE-cadherin and ${\beta}$-catenin protein dephosphorylation. In addition, 4-DAMP suppressed PTP1B activity by reducing cyclic adenosine monophosphate (cAMP), but not protein kinase $C{\alpha}$ ($PKC{\alpha}$). These data indicate that M3R preserves the endothelial barrier function through a mechanism potentially maintaining PTP1B activity, keeping the adherens junction proteins (AJPs) dephosphorylation.

• Biomedical Science Letters
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• v.21 no.3
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• pp.160-163
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• 2015

The effects of hypothermic treatment ($32^{\circ}C$) on recovery from ischemia are controversial because the precise mechanisms of hypothermia remain unclear. We demonstrated previously that hypothermia induces beta-catenin-interacting protein 1 (CTNNBIP1) gene expression in vitro. In this study, we evaluated the effects of various hypothermic conditions, including lithium chloride treatment, on CTNNBIP1 gene expression. The results show that short-term hypothermic treatment resulted in relatively higher CTNNBIP1 gene expression than that of a longer treatment. These findings indicate that hypothermia controls CTNNBIP1 gene expression, which may provide clues to develop treatments to recover from and diagnose ischemia.

• Korean Journal of Pharmacognosy
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• v.49 no.1
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• pp.28-39
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• 2018

This study investigated the effect of snail extract on the growth parameters of old female rats (27 weeks). Rats were administered orally with snail extract at a dose of 100 mg/kg, 200 mg/kg, chondroitin sulfate 10 mg/kg and 0.9% saline (control) for 8 weeks. Bone mineral density (BMD) and serum concentrations of insulin-like growth factor 1 (IGF-1) and insulinlike growth factor-binding protein 3 (IGFBP-3) were significantly higher in rats exposed to snail extract for 8 weeks. MG-63 cells (human osteoblast-like cells) were treated with snail extract for 48 h. Their differentiation and proliferation was investigated with Western blot and morphological changes observed via immunofluorescence staining of ${\beta}-catenin$. Treatment with snail extract significantly increased the levels of growth factors including ${\beta}-catenin$ and IGF-1. The snail extract affected osteoblast formation. Morphological changes in MG-63 cells were observed via immunofluorescence staining. Treatment with snail extract increased the expression of ${\beta}-catenin$ in MG-63 cells. Results suggest that the treatment of MG-63 cells with snail extract increased the longitudinal growth and growth factor levels. Snail extract may be pharmacologically effective in osteogenic differentiation in vitro and represents a potential therapeutic agent for bone formation.

• Journal of Plant Biotechnology
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• v.48 no.2
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• pp.106-114
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• 2021

We evaluated the anti-cancer activity against human prostate cancer cells and the associated molecular mechanism of extracts from the branches of Rhamnus yoshinoi (RYB). Treatment with RYB suppressed viability of human prostate cancer cells (PC-3) and decreased protein levels of both β-catenin and T-cell factor 4 (TCF4). This was reflected in reduced TCF4 mRNA, but not decreased β-catenin mRNA. PC-3 cells were pretreated with the proteosome inhibitor MG132 before treatment with RYB, which blocked RYB-mediated down regulation of β-catenin in PC-3 cells, thus confirming that RYB promotes the proteasomal degradation of β-catenin. RYB induced β-catenin phosphorylation, and GSK-3β inhibition by LiCl blocked the phosphorylation and proteasomal degradation of β-catenin by RYB. These results suggest that GSK-3β may be an important upstream kinase for RYB-mediated regulation of β-catenin. Finally, GC/MS analysis of RYB identified 18 compounds. Based on these findings, RYB shows potential for development as a therapeutic agent for prostate cancer.

• Journal of Biomedical Engineering Research
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• v.41 no.6
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• pp.235-246
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• 2020

This study aimed to evaluate the inhibitory effect of micro-current stimulation(MCS) on adipogenesis regarding with Wnt/β-catenin pathway using the ob/ob mouse and 3T3-L1 cell line. 6-week old ob/ob male mice were equally assigned to four groups: obese group(ob), obese with MCS groups(50 μA, 200 μA, and 400 μA). 6-week old C57BL/6J male mice were assigned to the control group(CON). We analyzed abdominal adipose tissue volume by using in vivo micro-CT and measured the body weight, feed intake, liver weight and triglycerides in serum. All the MCS groups showed that significantly reduced body weight and triglycerides in serum. In the case of liver weight and abdominal adipose tissue volume, the inhibitory effect of adipogenesis was shown in the 200 μA and 400 μA groups. To elucidate the anti-obesity effect of MCS, β-catenin, C/EBPα and FAS protein expressions were analyzed by western blotting. β-catenin expression was upregulated, C/EBPα and FAS expression were down-regulated in the relatively high-intensity groups(200 μA and 400 μA). Thus, the 200 μA and 400 μA for the intensity of MCS were chosen for cell experiments. In the 3T3-L1 cell line, Wnt/β-catenin pathway including Wnt10b, Wnt3a, β-catenin and Cyclin D1 was activated in all MCS groups. Accordingly, the expression level of C/EBPα was decreased during the differentiation and lipid droplet was significantly reduced in Oil red O staining results. These results suggest that the Wnt/β-catenin signaling might be activated by MCS with current intensities between 200-400 μA and it may lead to anti-obesity effects.