• Molecules and Cells
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• v.37 no.2
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• pp.178-186
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• 2014

Differential transcription of the clusterin (CLU) gene yields two CLU isoforms, a nuclear form (nCLU) and a secretory form (sCLU), which play crucial roles in prostate tumorigenesis. Pro-apoptotic nCLU and anti-apoptotic sCLU have opposite effects and are differentially expressed in normal and cancer cells; however, their regulatory mechanisms at the transcriptional level are not yet known. Here, we examined the transcriptional regulation of nCLU in response to hypoxia. We identified three putative hypoxia response elements (HREs) in the human CLU promoter between positions -806 and +51 bp. Using a luciferase reporter, electrophoretic gel mobility shift, and chromatin immunoprecipitation assays, we further showed that hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) bound directly to these sites and activated transcription. Exposure to the hypoxia-mimetic compound $CoCl_2$, incubation under 1% $O_2$ conditions, or overexpression of HIF-$1{\alpha}$ enhanced nCLU expression and induced apoptosis in human prostate cancer PC3M cells. However, LNCaP prostate cancer cells were resistant to hypoxia-induced cell death. Methylation-specific PCR analysis revealed that the CLU promoter in PC3M cells was not methylated; in contrast, the CLU promoter in LNCap cells was methylated. Co-treatment of LNCaP cells with $CoCl_2$ and a demethylating agent promoted apoptotic cell death through the induction of nCLU. We conclude that nCLU expression is regulated by direct binding of HIF-$1{\alpha}$ to HRE sites and is epigenetically controlled by methylation of its promoter region.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8579-8587
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• 2016

Background: The molecular mechanisms linking breast cancer progression and inflammation still remain obscure. The aim of the present study was to investigate the possible association of angiopoeitin like protein 4 (ANGPTL4) and its regulatory factor, hypoxia inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$), with the inflammatory markers nuclear factor kappa B/p65 (NF-${\kappa}B$/P65) and interleukin-1 beta (IL-$1{\beta}$) in order to evaluate their role in inflammation associated breast cancer progression. Materials and Methods: Angiopoietin-like protein 4 (ANGPTL4) mRNA expressions were evaluated using quantitative real time PCR and its protein expression by immunohistochemistry. DNA binding activity of NF-${\kappa}B$/P65 was evaluated by transcription factor binding immunoassay. Serum levels of ANGPTL4, HIF-$1{\alpha}$ and IL-$1{\beta}$ were immunoassayed. Tumor clinico-pathological features were investigated. Results: ANGPTL4 mRNA expressions and serum levels were significantly higher in high grade breast carcinoma ($1.47{\pm}0.31$ and $184.98{\pm}18.18$, respectively) compared to low grade carcinoma ($1.21{\pm}0.32$ and $171.76{\pm}7.58$, respectively) and controls ($0.70{\pm}0.02$ and $65.34{\pm}6.41$, respectively), (p<0.05). Also, ANGPTL4 high/moderate protein expression was positively correlated with tumor clinico-pathological features. In addition, serum levels of HIF-$1{\alpha}$ and IL-$1{\beta}$ as well as NF-${\kappa}B$/P65 DNA binding activity were significantly higher in high grade breast carcinoma ($148.54{\pm}14.20$, $0.79{\pm}0.03$ and $247.13{\pm}44.35$ respectively) than their values in low grade carcinoma ( $139.14{\pm}5.83$, $0.34{\pm}0.02$ and $184.23{\pm}37.75$, respectively) and controls ($33.95{\pm}3.11$, $0.11{\pm}0.02$ and $7.83{\pm}0.92$, respectively), (p<0.001). Conclusion: ANGPTL4 high serum levels and tissue expressions in advanced grade breast cancer, in addition to its positive correlation with tumor clinico-pathological features and HIF-$1{\alpha}$ could highlight its role as one of the signaling factors involved in breast cancer progression. Moreover, novel correlations were found between ANGPTL4 and the inflammatory markers, IL-$1{\beta}$ and NF-${\kappa}B$/p65, in breast cancer, which may emphasize the utility of these markers as potential tools for understanding interactions for axes of carcinogenesis and inflammation contributed for cancer progression. It is thus hoped that the findings reported here would assist in the development of new breast cancer management strategies that would promote patients' quality of life and ultimately improve clinical outcomes. However, large-scale studies are needed to verify these results.

• Molecules and Cells
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• v.28 no.6
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• pp.537-543
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• 2009

Keratinocyte overgrowth after UVB exposure is believed to contribute to skin photoageing and cancer development. However, little is known about the transcription factors that epigenetically regulate keratinocyte response to UVB. Recently, $HIF-1{\alpha}$ was found to play a role in epidermal homeostasis by controlling the keratinocyte cell cycle, and thus, we hypothesized that $HIF-1{\alpha}$ is involved in UVB-induced keratinocyte growth. In cultured keratinocytes, $HIF-1{\alpha}$ was found to be down-regulated shortly after UVB exposure and to be involved in UVB-induced proliferation. In mice repeatedly treated with UVB, the epidermis became hyperplasic and keratinocytes lacked $HIF-1{\alpha}$ in nuclei. Based on these results, we suggest that the deregulation of $HIF-1{\alpha}$ is associated with UVB-induced hyperplasia of the epidermis. This work provides insight of the molecular mechanism underlying UV-induced photoageing and skin cancer development.

• Korean Journal of Radiology
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• v.20 no.5
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• pp.830-843
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• 2019

Objective: To examine the potential of intravoxel incoherent motion (IVIM) and blood oxygen level-dependent (BOLD) magnetic resonance imaging for detecting renal changes after iodinated contrast-induced acute kidney injury (CI-AKI) development in a diabetic rabbit model. Materials and Methods: Sixty-two rabbits were randomized into 2 groups: diabetic rabbits with the contrast agent (DCA) and healthy rabbits with the contrast agent (NCA). In each group, 6 rabbits underwent IVIM and BOLD imaging at 1 hour, 1 day, 2 days, 3 days, and 4 days after an iohexol injection while 5 rabbits were selected to undergo blood and histological examinations at these specific time points. Iohexol was administrated at a dose of 2.5 g I/kg of body weight. Further, the apparent transverse relaxation rate (R2^*), average pure molecular diffusion coefficient (D), pseudo-diffusion coefficient (D^*), perfusion fraction (f) were calculated. Results: The D and f values of the renal cortex (CO) and outer medulla (OM) were significantly decreased compared to baseline values in the 2 groups 1 day after the iohexol injection (p < 0.05). A marked reduction in the D^* values for both the CO and OM was also observed after 1 hour in each group (p < 0.05). In the OM, a persistent elevation of the R2^* was detected for 4 days in the DCA group (p < 0.05). Histopathological changes were prominent, and the pathological features of CI-AKI aggravated in the DCA group until day 4. The D, f, and R2^* values significantly correlated with the histological damage scores, hypoxia-inducible transcription factor-1α expression scores, and serum creatinine levels. Conclusion: A combination of IVIM and BOLD imaging may serve as a noninvasive method for detecting and monitoring CI-AKI in the early stages in the diabetic kidney.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.66-71
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• 2016

Delphinidin is a blue-red pigment and one of the major anthocyanins in plants. It plays an important role in anti-oxidant, anti-inflammatory, anti-mutagenic and anti-cancer properties. In this study, we investigated the inhibitory effects of delphinidin on vascular endothelial growth factor (VEGF) gene expression, an important factor involved in angiogenesis and tumor progression in human prostate cancer. Delphinidin decreased levels of epidermal growth factor (EGF)-induced VEGF mRNA expression in PC-3M cells. The expression of the EGF-induced hypoxia inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) and signaling transducer and activator of transcription 3 (STAT3) proteins, which are the major transcription factors for VEGF, were inhibited by delphinidin. In addition, delphinidin decreases HRE-promoter reporter gene activity, suggesting that delphinidin can suppress the transcription of HIF-$1{\alpha}$ under EGF induction, leading to a decrease in the expression of VEGF. Delphinidin specifically suppressed the phosphorylation of Akt, p70S6K, and 4EBP1, but not the phosphorylation of EGFR. Therefore, our results suggest that delphinidin may inhibit human prostate cancer progression and angiogenesis by inhibiting HIF-$1{\alpha}$, STAT3 and VEGF gene expression.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.178-185
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• 2009

Background: Epigallocatechin-3-gallate (EGCG) is the major catechin in green tea, and has shown antiproliferative, antiangiogenic, antimetastatic and cell cycle pertubation activity in various tumor models. Hypoxia can be induced because angiogenesis is insufficient for highly proliferating cancer. Hypoxia-inducible factor-1$\alpha$ (HIF-1$\alpha$) and its downstream target, vascular endothelial growth factor (VEGF), are important for angiogenesis, tumor growth and metastasis. The aim of this study was to determine how hypoxia could cause changes in the cellular phenomena and microenvironment in a non-small cell culture system and to examine the effects of EGCG on a HIF-1$\alpha$ and VEGF in A549 cell line. Methods: A549 cells, a non-small cell lung cancer cell line, were cultured with DMEM and 10% fetal bovine serum. A decrease in oxygen tension was induced using a hypoxia microchamber and a $CO_2-N_2$ gas mixture. Gas analysis and a MTT assay were performed. The A549 cells were treated with EGCG (0, 12.5, 25, 50 ${\mu}mol/L$), and then examined by real-time-PCR analysis of HIF-1$\alpha$, VEGF, and $\beta$-actin mRNA. Results: Hypoxia reduced the proliferation of A549 cells from normoxic conditions. EGCG inhibited HIF-1$\alpha$ transcription in A549 cells in a dose-dependent manner. Compared to HIF-1$\alpha$, VEGF was not inhibited by EGCG. Conclusion: HIF-1$\alpha$ can be inhibited by EGCG. This suggests that targeting HIF-1$\alpha$ with a EGCG treatment may have therapeutic potential in non-small cell lung cancers.

• Archives of Plastic Surgery
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• v.42 no.1
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• pp.59-67
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• 2015

Background Negative-pressure wound therapy (NPWT) induces angiogenesis and collagen synthesis to promote tissue healing. Although acetic acid soaks normalize alkali wound conditions to raise tissue oxygen saturation and deconstruct the biofilms of chronic wounds, frequent dressing changes are required. Methods Combined use of NPWT and acetic acid irrigation was assessed in the treatment of chronic wounds, instilling acetic acid solution (1%) beneath polyurethane membranes twice daily for three weeks under continuous pressure (125 mm Hg). Clinical photographs, pH levels, cultures, and debrided fragments of wounds were obtained pre- and posttreatment. Tissue immunostaining (CD31, Ki-67, and CD45) and reverse transcription-polymerase chain reaction (vascular endothelial growth factor [VEGF], vascular endothelial growth factor receptor [VEGFR]; procollagen; hypoxia-inducible factor 1 alpha [HIF-1-alpha]; matrix metalloproteinase [MMP]-1,-3,-9; and tissue inhibitor of metalloproteinase [TIMP]) were also performed. Results Wound sizes tended to diminish with the combined therapy, accompanied by drops in wound pH (weakly acidic or neutral) and less evidence of infection. CD31 and Ki-67 immunostaining increased (P<0.05) post-treatment, as did the levels of VEGFR, procollagen, and MMP-1 (P<0.05), whereas the VEGF, HIF-1-alpha, and MMP-9/TIMP levels declined (P<0.05). Conclusions By combining acetic acid irrigation with negative-pressure dressings, both the pH and the size of chronic wounds can be reduced and infections be controlled. This approach may enhance angiogenesis and collagen synthesis in wounds, restoring the extracellular matrix.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.2
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• pp.108-113
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• 2020

Objective: Endometrial fibrosis, the primary pathological feature of intrauterine adhesion, may lead to disruption of endometrial tissue structure, menstrual abnormalities, infertility, and recurrent pregnancy loss. At present, no ideal therapeutic strategy exists for this fibrotic disease. Eupatilin, a major pharmacologically active flavone from Artemisia, has been previously reported to act as a potent inducer of dedifferentiation of fibrotic tissue in the liver and lung. However, the effects of eupatilin on endometrial fibrosis have not yet been investigated. In this study, we present the first report on the impact of eupatilin treatment on transforming growth factor beta (TGF-β)-induced endometrial fibrosis. Methods: The efficacy of eupatilin on TGF-β-induced endometrial fibrosis was assessed by examining changes in morphology and the expression levels of fibrosis markers using immunofluorescence staining and quantitative real-time reverse-transcription polymerase chain reaction. Results: Eupatilin treatment significantly reduced the fibrotic activity of TGF-β-induced endometrial fibrosis in Ishikawa cells, which displayed more circular shapes and formed more colonies. Additionally, the effects of eupatilin on fibrotic markers including alpha-smooth muscle actin, hypoxia-inducible factor 1 alpha, collagen type I alpha 1 chain, and matrix metalloproteinase-2, were evaluated in TGF-β-induced endometrial fibrosis. The expression of these markers was highly upregulated by TGF-β pretreatment and recovered to the levels of control cells in response to eupatilin treatment. Conclusion: Our findings suggest that suppression of TGF-β-induced signaling by eupatilin might be an effective therapeutic strategy for the treatment of endometrial fibrosis.

• Journal of Gastric Cancer
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• v.11 no.1
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• pp.16-22
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• 2011

Purpose: Eupatilin is an antioxidative flavone and a phytopharmaceutical derived from Artemisia asiatica. It has been reported to possess anti-tumor activity in some types of cancer including gastric cancer. Eupatilin may modulate the angiogenesis pathway which is part of anti-inflammatory effect demonstrated in gastric mucosal injury models. Here we investigated the anti-tumor effects of eupatilin on gastric cancer cells and elucidated the potential underlying mechanism whereby eupatilin suppresses angiogenesis and tumor growth. Materials and Methods: The impact of eupatilin on the expression of angiogenesis pathway proteins was assessed using western blots in MKN45 cells. Using a chromatin immunoprecipitation assay, we tested whether eupatilin affects the recruitment of signal transducer and activator of transcription 3 (STAT3), aryl hydrocarbon receptor nuclear translocator (ARNT) and hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) to the human VEGF promoter. To investigate the effect of eupatilin on vasculogenesis, tube formation assays were conducted using human umbilical vein endothelial cells (HUVECs). The effect of eupatilin on tumor suppression in mouse xenografts was assessed. Results: Eupatilin significantly reduced VEGF, ARNT and STAT3 expression prominently under hypoxic conditions. The recruitment of STAT3, ARNT and HIF-$1{\alpha}$ to the VEGF promoter was inhibited by eupatilin treatment. HUVECs produced much foreshortened and severely broken tubes with eupatilin treatment. In addition, eupatilin effectively reduced tumor growth in a mouse xenograft model. Conclusions: Our results indicate that eupatilin inhibits angiogenesis in gastric cancer cells by blocking STAT3 and VEGF expression, suggesting its therapeutic potential in the treatment of gastric cancer.

• Tuberculosis and Respiratory Diseases
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• v.57 no.1
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• pp.37-46
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• 2004

Background : Lung pericytes are important constituent cells of blood-air barrier in pulmonary microvasculature. These cells take part in the control of vascular contractility and permeability. In this study, it was hypothesized that change of lung pericytes might be attributable to pathologic change in microvasculature in acute lung injury. The purpose of this study was how hypoxia change proliferation and genetic expression in lung pericytes. Methods : From the lungs of several Sprague-Dawley rats, performed the primary culture of lung pericytes and subculture. Characteristics of lung pericytes were confirmed with stellate shape in light microscopy and immunocytochemistry. 2% concentration of oxygen and $200{\mu}M$ $CoCl_2$ were treated to cells. Tryphan blue method and reverse transcription-polymerase chain reaction were done. Results : 1. We established methodology for primary culture of lung pericytes. 2. Hypoxia inhibited cellular proliferation in pericytes. 3. Hypoxia could markedly induce vascular endothelial growth factor(VEGF) and smad-2. 4. Hypoxia-inducible factor-$1{\alpha}$(HIF-$1{\alpha}$) was also induced by 2% oxygen. Conclusion : Viability of lung pericytes are inhibited by hypoxia. Hypoxia can stimulate expression of hypoxia-responsive genes. Pericytic change may be contributed to dysfunction of alveolar-capillary barrier in various pulmonary disorders.