• Molecules and Cells
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• 제44권10호
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• pp.710-722
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• 2021

Hypoxia, or low oxygen tension, is a hallmark of the tumor microenvironment. The hypoxia-inducible factor-1α (HIF-1α) subunit plays a critical role in the adaptive cellular response of hypoxic tumor cells to low oxygen tension by activating gene-expression programs that control cancer cell metabolism, angiogenesis, and therapy resistance. Phosphorylation is involved in the stabilization and regulation of HIF-1α transcriptional activity. HIF-1α is activated by several factors, including the mitogen-activated protein kinase (MAPK) superfamily. MAPK phosphatase 3 (MKP-3) is a cytoplasmic dual-specificity phosphatase specific for extracellular signal-regulated kinase 1/2 (Erk1/2). Recent evidence indicates that hypoxia increases the endogenous levels of both MKP-3 mRNA and protein. However, its role in the response of cells to hypoxia is poorly understood. Herein, we demonstrated that small-interfering RNA (siRNA)-mediated knockdown of MKP-3 enhanced HIF-1α (not HIF-2α) levels. Conversely, MKP-3 overexpression suppressed HIF-1α (not HIF-2α) levels, as well as the expression levels of hypoxia-responsive genes (LDHA, CA9, GLUT-1, and VEGF), in hypoxic colon cancer cells. These findings indicated that MKP-3, induced by HIF-1α in hypoxia, negatively regulates HIF-1α protein levels and hypoxia-responsive genes. However, we also found that long-term hypoxia (>12 h) induced proteasomal degradation of MKP-3 in a lactic acid-dependent manner. Taken together, MKP-3 expression is modulated by the hypoxic conditions prevailing in colon cancer, and plays a role in cellular adaptation to tumor hypoxia and tumor progression. Thus, MKP-3 may serve as a potential therapeutic target for colon cancer treatment.

• Radiation Oncology Journal
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• 제27권4호
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• pp.218-227
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• 2009

목 적: 전립샘암 세포주 DU 145에서 엑스선과 중성자선에 의한 HIF-$1\alpha$와 아포프토시스 발현의 차이를 비교함으로써 엑스선과 중성자선의 방사선생물학적 차이의 기전을 알아보고자 한다. 대상 및 방법: 누드 마우스에 DU 145 전립샘암 세포주를 주입한 후 2 Gy 엑스선, 10 Gy 엑스선, 0.6 Gy 중성자선, 3.3 Gy 중성자선을 각각 조사했다. 엑스선을 조사한 군과 중성자선을 조사한 군에서 HIF-$1\alpha$, Bcl-2, Bax, 아포프토시스 발현 정도를 면역조직화학 염색과 western blotting을 이용하여 비교하였다. 아포토시스의 정도는 terminal deoxynucleotidyl biotin-dUTP nick end labeling (TUNEL) 염색을 이용하여 비교하였다. 결 과: 방사선 조사 1일째, X선을 조사한 군과 비교했을 때, 중성자선을 조사한 군에서 HIF-$1\alpha$와 Bcl-2의 발현은 감소하였고, Bax와 아포프토시스 세포의 수는 증가하였다. Bcl-2/Bax 비는 중성자선을 조사한 군에서 의미 있게 감소하였다. 이러한 HIF-$1\alpha$, Bcl-2, Bax, Bcl-2/Bax 비, 아포프토시스 발현의 차이는 방사선 조사 5일째에도 동일하게 유지되어 나타났다. 또한, HIF-$1\alpha$ 발현은 방사선 조사 5일째 Bcl-2 (p=0.031), Bax (p=0.037), TUNEL (p=0.016) 발현과 연관성을 보였다. 결 론: 중성자선 조사한 경우 엑스선에 비해 HIF-$1\alpha$와 Bcl-2 발현, Bcl-2/Bax 비가 감소하고, Bax 발현은 증가하였다. 중성자선 치료의 광자선과 다른 방사선생물학적인 반응은 HIF-$1\alpha$와 그로 인한 아포프토시스 관련 단백질 발현의 차이와 연관성이 있을 것으로 생각한다.

• Experimental and Molecular Medicine
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• 제51권2호
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• pp.1.1-1.14
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• 2019

Hypoxia-inducible factor-$1{\alpha}$ ($HIF-1{\alpha}$) mediates tumor cell adaptation to hypoxic conditions and is a potentially important anticancer therapeutic target. We previously developed a method for synthesizing a benzofuran-based natural product, (R)-(-)-moracin-O, and obtained a novel potent analog, MO-460 that suppresses the accumulation of $HIF-1{\alpha}$ in Hep3B cells. However, the molecular target and underlying mechanism of action of MO-460 remained unclear. In the current study, we identified heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) as a molecular target of MO-460. MO-460 inhibits the initiation of $HIF-1{\alpha}$ translation by binding to the C-terminal glycinerich domain of hnRNPA2B1 and inhibiting its subsequent binding to the 3'-untranslated region of $HIF-1{\alpha}$ mRNA. Moreover, MO-460 suppresses $HIF-1{\alpha}$ protein synthesis under hypoxic conditions and induces the accumulation of stress granules. The data provided here suggest that hnRNPA2B1 serves as a crucial molecular target in hypoxiainduced tumor survival and thus offer an avenue for the development of novel anticancer therapies.

• 동의생리병리학회지
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• 제26권4호
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• pp.437-440
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• 2012

Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that regulates various cellular processes such as cell survival, angiogenesis and proliferation. In the present study, we examined that Cryptotanshione(CT), a tanshinone from oriental traditional medicinal herb Danshen (Salvia miltiorrhiza Bunge), had the inhibitory effects on hypoxia-mediated activation of STAT3 in androgen independent human prostate cancer PC-3 cells. CT inhibited the protein expression of hypoxia-inducible factor-1alpha (HIF-$1{\alpha}$) under hypoxic condition. Consistently, CT blocked hypoxia-induced phosphorylation and nuclear accumulation of STAT3. In addition, CT reduced cellular of vascular endothelial growth factor (VEGF), a critical angiogenic factor and a target gene of STAT3 induced under hypoxia. Of note, chromatin immunoprecipitation (ChiP) assay revealed that CT inhibited binding of STAT3 to VEGF promoter. Taken together, our results suggest that CT has anti-angiogenic activity by disturbing the binding STAT3 to the VEGF promoter in PC-3 cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10151-10156
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• 2015

4-Hydroxynonenal (4-HNE) is a stable end product of lipid peroxidation, which has been shown to play an important role in cell signal transduction, while increasing cell growth and differentiation. 4-HNE could inhibit phosphatase and tensin homolog (PTEN) activity in hepatocytes and increased levels have been found in human invasive breast cancer. Here we report that 4-HNE increased the cell growth of breast cancer cells as revealed by colony formation assay. Moreover, vascular endothelial growth factor (VEGF) expression was elevated, while protein levels of hypoxia inducible factor 1 alpha (HIF-$1{\alpha}$) were up-regulated. Sirtuin-3 (SIRT3), a major mitochondria NAD+-dependent deacetylase, is reported to destabilize HIF-$1{\alpha}$. Here, 4-HNE could inhibit the deacetylase activity of SIRT3 by thiol-specific modification. We further demonstrated that the regulation by 4-HNE of levels of HIF-$1{\alpha}$ and VEGF depends on SIRT3. Consistent with this, 4-HNE could not increase the cell growth in SIRT3 knockdown breast cancer cells. Additionally, 4-HNE promoted angiogenesis and invasion of breast cancer cells in a SIRT3-dependent manner. In conclusion, we propose that 4-HNE promotes growth, invasion and angiogenesis of breast cancer cells through the SIRT3-HIF-$1{\alpha}$-VEGF axis.

• 생명과학회지
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• 제22권1호
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• pp.41-48
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• 2012

봉독은 동양의학에서 관절염, 류마티즘 및 각종 암을 포함하여 다양한 질병을 치료하기 위하여 이용되었다. 최근 봉독의 신생혈관 억제효과에 대한 연구가 보고되었으나 정확한 분자메커니즘에 대해서는 보고가 미흡하다. 따라서, 본 연구는 봉독이 인간결장암세포인 HCT116세포에서 신생혈관생성과 종양진행에 중요한 역할을 하는 HIF-$1{\alpha}$와 VEGF 발현 억제효과를 조사하였다. 그 결과 봉독은 $CoCl_2$로 유도한 저산소 상태에서 VEGF와, HIF-$1{\alpha}$의 발현을 감소시키며 HIF-$1{\alpha}$의 promoter 영역인 HRE 활성을 억제하였다. 이러한 봉독의 HIF-$1{\alpha}$ 발현억제효과는 ERK1/2의 인산화 조절을 통한 것이며, 봉독은 p38, JNK, AKT의 인산화에는 영향을 끼치지 않았다. 또한 봉독의 효과를 나타내는 단일물질 탐색을 위해 봉독의 생리활성 물질로 알려진 아파민과 멜리틴을 조사한 결과, HIF-$1{\alpha}$와 VEGF 억제효과는 아파민에 기인하는 것이라고 예상 할 수 있었다. 이와 같은 결과를 통하여 본 연구에서는 봉독의 혈관신생 억제에 대한 새로운 신호전달기전 및 인간 결장암세포 전이 억제제로서의 잠재성을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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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.

• 한방안이비인후피부과학회지
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• 제19권3호통권31호
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• pp.1-12
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• 2006

Objective : Angiogenesis is an essential process for metastasis of solid tumors and Psoriasis. Lots of Researches for anti-angiogenic effect to angiogenic factors have been carried out in the world. So this experiment was carried out for whether Lacca Sinica Exsiccata(LSE) extracts have an anti-angiogenic effect for angiogenic factors. Methods: To investigate the roles of the LSE extracts, we performed MIS assay, western blots using HaCaT cells and HepG2 cells. And then, HaCaT cells were treated with 10, 50, 100, 250, $500{\mu}g/ml$ LSE extracts. After 4hrs, HaCaT cells were theated with IGF-II protein for 1hr. HepG2 cells were treated with 1, 10, 25, 50, 100, 200 ${\mu}g/ml$ LSE extracts. After 4hrs, HepG2 cells were theated with $CoCl_2$ for 24hrs Results: 1. In $50{\mu}g/ml$ and $100{\mu}g/ml$ density we confirmed the inhibition effect of LSE extracts to $HIF-1{\alpha}$ activation which was induced by IGF-II in HaCaT cells. 2. In $50{\mu}g/ml$ density we confirmed the inhibition effect of LSE extracts to $HIF-1{\alpha}$ activation which was induced by $CoCl_2$ in HepG2 cells. 3. In $25{\mu}g/ml$ density we confirmed the inhibition effect of LSE extracts to VEGF activation which was induced by $CoCl_2$ in HepG2 cells. Conclusion: The above-mentioned results proved that LSE extracts reduced $HIF-1{\alpha}$ protein level in the HaCaT cells and HepG2 cells. These results suggest that inhibition of HaCaT cell and HepG2 cell proliferation by LSE extracts contributes to the anti-angiogenic activities on the keratinocytes and hepatocellular carcinoma.

• 동의생리병리학회지
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• 제20권3호
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• pp.557-562
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• 2006

Hypoxia induced angiogenesis and inflammation are essential processes for metastasis and progress of solid tumors. We examined the anti-angiogenic and inflammation related activity of Kochiae Fructus (KF) extract. To investigate the roles of the KF extract, we performed MTS assay, western blots using HaCaT cells and $HepG_2$ cells. The results are as follows. The protein level of $HIF-1{\alpha}$ was reduced when induced by $CoCl_2$ in $HepG_2$ cells treated with KF extract and induced by IGF-11 in HaCaT cells treated with KF extract. KF extract reduced the mRNA level of VEGF in HaCaT cells and KF extract reduced the protein level of iNOS in HaCaT cells. These results suggest that KF extract contributes to the anti-angiogenic and anti-inflammatory activities and also we could assume that KF extract act as antioxidant or anti-inflammatory agents via reduction of $HIF-1{\alpha}$.

• The Korean Journal of Physiology and Pharmacology
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• 제20권1호
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• pp.53-62
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• 2016

Mesenchymal stem cells (MSCs) in the bone marrow and other somatic tissues reside in an environment with relative low oxygen tension. Cobalt chloride ($CoCl_2$) can mimic hypoxic conditions through transcriptional changes of some genes including hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) and vascular endothelial growth factor (VEGF). This study evaluated the potential role of $CoCl_2$ preconditioning on multi-lineage differentiation of C3H/10T1/2, a murine MSC line to understand its possible molecular mechanisms in vitro. $CoCl_2$ treatment of MSCs markedly increased HIF-$1{\alpha}$ and VEGF mRNA, and protein expression of HIF-$1{\alpha}$. Temporary preconditioning of MSCs with $CoCl_2$ induced up-regulation of osteogenic markers including alkaline phosphatase, osteocalcin, and type I collagen during osteogenic differentiation, followed by enhanced mineralization. $CoCl_2$ also increased chondrogenic markers including aggrecan, sox9, and type II collagen, and promoted chondrocyte differentiation. $CoCl_2$ suppressed the expression of adipogenic markers including $PPAR{\gamma}$, aP2, and $C/EBP{\alpha}$, and inhibited adipogenesis. Temporary preconditioning with $CoCl_2$ could affect the multi-lineage differentiation of MSCs.