• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권1호
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• pp.1-8
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• 2010

Background and Purpose: Vascular endothelial growth factor (VEGF)-C and VEGF receptor (VEGFR)-3 are involved in tumor lymphangiogenesis. Oral mucosal squamous cell carcinoma (OMSCC) preferentially metastasizes to cervical lymph nodes, so we investigated the expression and distribution of VEGFR-3 signaling proteins in OMSCC. Materials and Methods: Tissue samples of 18 OMSCC, 10 oral mucosal leukoplakia, and 3 normal oral mucosa were evaluated for expression of VEGF-C, VEGF-D, and VEGFR-3 by immunohistochemical staining. The presence of lymphatic vessels was determined using D2-40 staining, by which we also measured lymphatic vessel density (LVD). Results: 72% (13/18) and 56% (10/18) of tissue samples showed VEGF-C and VEGF-D immunopositivity in tumor cells and tumor-associated endothelial cells. VEGFR-3 was also expressed in most of OMSCC, which was up-regulated when compared with normal mucosa or with leukoplakia. Furthermore, LVD was higher in OMSCC than in leukoplakia. Conclusion: Taken together, our results suggest that autocrine activation of lymphatic endothelial cell via VEGFR-3 by VEGF-C and/or VEGF-D could be involved in progression of OMSCC. Therefore, VEGF-C/VEGFR-3 signaling pathway can be a molecular target for anti-metastatic therapy in OMSCC.

• Journal of Ginseng Research
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• 제43권2호
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• pp.305-311
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• 2019

Background: Gintonin is a ginseng-derived exogenous ligand of the G protein-coupled lysophosphatidic acid (LPA) receptor. We previously reported that gintonin stimulates gliotransmitter release in primary cortical astrocytes. Astrocytes play key roles in the functions of neurovascular systems. Although vascular endothelial growth factor (VEGF) is known to influence the normal growth and maintenance of cranial blood vessels and the nervous system, there is little information about the effect of gintonin on VEGF regulation in primary astrocytes, under normal and hypoxic conditions. Methods: Using primary cortical astrocytes of mice, the effects of gintonin on the release, expression, and distribution of VEGF were examined. We further investigated whether the gintonin-mediated VEGF release protects astrocytes from hypoxia. Results: Gintonin administration stimulated the release and expression of VEGF from astrocytes in a concentration- and time-dependent manner. The gintonin-mediated increase in the release of VEGF was inhibited by the LPA1/3 receptor antagonist, Ki16425; phospholipase C inhibitor, U73122; inositol 1,4,5- triphosphate receptor antagonist, 2-APB; and intracellular $Ca^{2+}$ chelator, BAPTA. Hypoxia further stimulated astrocytic VEGF release. Gintonin treatment stimulated additional VEGF release and restored cell viability that had decreased due to hypoxia, via the VEGF receptor pathway. Altogether, the regulation of VEGF release and expression and astrocytic protection mediated by gintonin under hypoxia are achieved via the LPA receptor-VEGF signaling pathways. Conclusion: The present study shows that the gintonin-mediated regulation of VEGF in cortical astrocytes might be neuroprotective against hypoxic insults and could explain the molecular basis of the beneficial effects of ginseng on the central nervous system.

• Biomolecules & Therapeutics
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• 제31권4호
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• pp.456-465
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• 2023

Cervical tumors represent a prevalent form of cancer affecting women worldwide; current treatment options involve surgery, radiotherapy, and chemotherapy. Angiogenesis, the process of new blood vessel formation, is a crucial factor in cervical tumor growth. The molecular mechanisms underlying the effects of the liver kinase B1 (LKB1/STK11) tumor suppressor protein on tumor angiogenesis have not been elucidated. Therefore, we investigated the role of LKB1 in cervical tumor angiogenesis both in vitro and in vivo in this study. Our results demonstrated that LKB1 inhibited cervical tumor angiogenesis by suppressing the expression of angiogenesis-related factors such as vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1α. LKB1 directly affected both carcinoma and vascular endothelial cells, resulting in a significant reduction in tumor growth and angiogenesis. Furthermore, LKB1 was found to bind to VEGF receptor 2 (VEGFR-2) and target the VEGFR-2-mediated protein kinase B/mechanistic target of rapamycin signaling pathway in endothelial cells, thereby reducing cervical tumor growth and angiogenesis. Our study provides new insights into the molecular mechanisms underlying the anti-tumor and anti-angiogenic effects of LKB1 in cervical cancer. These findings will help develop new therapeutic strategies for cervical cancer.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권3호
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• pp.85-93
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• 2014

Purpose: Nodal metastasis is the main prognostic factor in the patients with oral squamous cell carcinoma (OSCC). We investigated the association between tumor-associated lymphatics and OSCC characteristics. Methods: Thirty-four specimens were used for the immunohistochemical staining with the antibody for vascular endothelial growth factor (VEGF)-C, VEGF-D, VEGF receptor (VEGFR)-3, phosphorylated VEGFR-3, D2-40, and matrix metallproteinases (MMPs). We observed the distribution of the lymphangiogenic factors and quantified the degree of expression. We determined lymphatic vessel density (LVD) and lymphatic vessel dilatation with D2-40 immunostaining. We assessed the association of LVD or lymphatic vessel dilatation with tumor progression or tumor differentiation. Results: OSCC cells expressed lymphangiogenic ligands. Lymphangiogenic receptor, VEGFR-3, was expressed and activated in some tumor cells as well as in tumor-associated endothelial cells. LVD was not associated with tumor size or nodal status, but lymphatic vessel dilatation was higher in tumors with nodal metastasis, and also higher in poorly differentiated tumors. In stromal area of OSCC, MMP-1 and MMP-10 were up-regulated and the basement membrane of tumor-associated endothelial cells was destroyed by these collagenases. Conclusion: In the primary tumors with nodal metastasis, especially in poorly differentiated OSCC, tumor cells invaded the dilated lymphatic vessels via ruptured sites. MMP-1 and MMP-10 are important in the lysis of the glycocalyx inside the tumor-associated lymphatic endothelial cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권2호
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• pp.55-65
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• 2009

Purpose: We determined the therapeutic effects of blockade of epidermal growth factor(EGF) and vascular endothelial growth factor(VEGF) receptor tyrosine kinases on the growth of oral squamous cell carcinoma(OSCC) xenografted in athymic nude mice. Experimental Design: We investigated the in vivo antitumor effects of a tyrosine kinase inhibitor for EGFR and VEGFR-2, AEE788 in a mouth floor(orthotopic) tumor model. Nude mice with orthotopic tumors were randomized to receive AEE788, paclitaxel, a combination of AEE788 and paclitaxel, or control. Antitumor mechanisms of AEE788 were determined by immunohistochemical/immunofluorescent and apoptosis assays. Results: Tumors of mice treated with AEE788 demonstrated down-regulation of phosphorylated EGFR, phosphorylated VEGFR and their downstream mediators(pMAPK and pAkt), decreased proliferative index, decreased microvessel density(MVD). As a result, growth of the primary tumor and nodal metastatic potentials were inhibited by AEE788. Conclusion: These data show that EGFR and VEGFR can be molecular targets for the treatment of OSCC.

• Clinical and Experimental Pediatrics
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• 제48권8호
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• pp.886-893
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• 2005

목 적 : 가와사키병은 어린 소아에서 전신성 혈관염을 일으키는 가장 흔한 원인이다. 가와사키병이 발병한 경우 여러 혈관 성장인자들의 분비가 촉진되어 내막층의 증식과 신생 혈관 생성작용이 진행되면서 관상동맥이 재구성된다. 수년간 가와사키병의 치료제로 IVIG와 코르티코스테로이드가 사용되었으나 그 치료기전이 명확히 밝혀진 바는 없다. 이런 IVIG와 코르티코스테로이드가 가와사키병의 관상동맥합병증을 감소시키는데 어떠한 기전으로 작용하는지 알아보고자 본 연구에서는 Matrigel을 이용하여 in vitro에서 VEGF에 의해 유도된 내막세포 분화에 대한 IVIG와 methylprednisolone의 효과를 보고자 하였다. 방 법 : Matrigel을 이용하여 in vitro에서 VEGF에 의해 유도된 내막세포 분화에 대한 IVIG와 methylprednisolone의 효과를 보고자 VEGF, VEGF와 IVIG, VEGF와 VEGF antibody, VEGF와 methylprednisolone, VEGF, IVIG와 methylprednisolone을 각각 넣어주고, HUVECs를 18시간 동안 배양 후 튜브의 총 길이를 측정하였다. 결 과 : 1) IVIG의 농도를 25 mg/mL, 그리고 40 mg/mL로 증량하였을 경우 IVIG를 투여하지 않은 대조군에 비하여 통계학적으로 각각 유의한 세포수(HUVECs) 감소 효과를 관찰할 수 있었으며(P<0.001), 40 mg/mL를 처리한 경우가 25 mg/mL를 처리한 경우보다 세포수 감소 효과가 더 뚜렷하였다(P<0.05). 세포배양 시간에 따른 억제 효과는 25 mg/mL과 40 mg/mL에서 배양 후 24시간과 48시간 모두에서 대조군과 비교하여 통계학적으로 유의한 효과를 보였다(P<0.001). 2) VEGF 20 ng/mL를 처리한 군에 IVIG 40 mg/mL 또는 여러 농도의 methylprednisolone($10^{-12}M$, $10^{-9}M$ or $10^{-6}M$)을 처치해 주었을 때 튜브 형성이 유의하게 억제되었으며(P<0.05), methylprednisolone의 경우 그 억제 정도가 농도에 비례하여 일어났으나 IVIG 투여시 보다는 억제 효과가 약하였다. 한편, IVIG와 methylprednisolone와 병합투여한 경우는 methylprednisolone 농도에 상관없이 모두 튜브 형성을 잘 억제하였으며(P<0.001), IVIG만 단독 투여한 것과 통계적 차이는 없었다. 결 론 : 본 연구에서는 in vitro에서 VEGF가 HUVECs의 분화를 유도하고 분화된 내막세포의 맥관 형성이 IVIG와 methylprednisolone에 의해 저해된다는 것을 보여주었다. 이는 가와사키병의 관상동맥합병증이 생기는 기전 중 VEGF와 내막세포의 분화로 인해 일어나는 관상동맥의 재구성을 IVIG와 methylprednisolone이 억제한다는 것을 시사하며 치료 기전 중 하나로 제시될 수 있다.

• Journal of Gastric Cancer
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• 제14권3호
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• pp.196-203
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• 2014

Purpose: Vascular endothelial growth factor (VEGF) is one of the most important growth factors for metastatic tumors. To clarify the role of VEGF-A and C in patients with peptic ulcer disease (PUD) or gastric cancer (GC), we evaluated the expression levels of these two molecules. We also analyzed the effect of Helicobacter pylori infection on VEGF-A and C expression levels. Materials and Methods: Patients with dyspepsia who needed diagnostic endoscopy were selected and divided into three groups: nonulcer dyspepsia (NUD), PUD, and GC, according to their endoscopic and histopathological results. Fifty-two patients with NUD, 50 with PUD, and 38 with GC were enrolled in this study. H. pylori infection was diagnosed by the rapid urease test. After RNA extraction and synthesis of cDNA, the expression levels of VEGF-A and C were determined by quantitative reverse transcriptase polymerase chain reaction. Results: The VEGF-C expression level in the PUD and GC groups was significantly higher than that in the NUD group. Moreover, the VEGF-A expression level in the PUD and GC groups was higher than in the NUD group, although the differences were not statistically significant. Significant positive correlations were also observed between the expression levels of these two molecules in the PUD and GC groups. In addition, the expression levels of these two molecules were higher in H. pylori positive patients with PUD or GC than in H. pylori negative patients of the same groups; however, these differences did not reach statistical significance. Conclusions: Up-regulation of VEGF-C expression during gastric mucosal inflammation may play a role in the development of peptic ulcers or GC.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.27-31
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• 2012

Objectives: Expression of vascular endothelial growth factor C (VEGF-C)and vascular endothelial growth factor feceptor-3 (VEGFR-3) in laryngeal squamous carcinoma and its relationship to lymph node metastasis were investigated. Methods: VEGF-C and VEGFR-3 gene expression in 30 cases of normal laryngeal mucosa tissue (NLM), primary laryngeal carcinoma cell carcinomas (PLC) and cervical lymph nodes (CLN) was examined by reverse transcription polymerase chain reaction (RT-PCR). Protein levels of VEGF-C expression were determined by immunohistochemical staining in 60 cases of PLC. Results: Expression of VEGF-C and VEGFR-3 different among NLM, PLC and CLN in the same patient. In PLC, expression was significantly higher in lymph node positive group than in the lymph node negative group and associated with histological grade of differentiation; Expression of VEGF-C and VEGFR-3 was not linked with age, sex, site or T stage. Conclusions: A close correlation was found between VEGF-C/VEGFR-3 expression and lymph node metastasis in PLC, suggesting a role in metastasis of laryngeal carcinomas.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.257-263
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• 2014

Background: Vascular endothelial growth factor (VEGF), an endothelial cell specific mitogen, has been implicated as a critical factor influencing tumor related angiogenesis. The aim of present study was to evaluate the relationship between VEGF +936C>T and +405C>G polymorphisms of VEGF with risk of breast cancer in Punjab, India. Materials and Methods: We screened DNA samples of 192 sporadic breast cancer patients and 192 unrelated healthy, gender and age matched control individuals for VEGF +936C>T and +405C>G polymorphisms using the PCR-RFLP method. Results: For the VEGF +405C>G polymorphism, we observed significantly increased frequency of GG genotype in cases as compared to controls and strong association of +405GG genotype was observed with three fold risk for breast cancer (OR=3.07; 95%CI 1.41-6.65; p=0.003). For the +936C>T polymorphism, significant associations of CT and combined CT+TT genotypes were observed with elevated risk of breast cancer (p=0.021; 0.023). The combined genotype combinations of GG-CC and GG-CT of +405C>G and +936C>T polymorphisms were found to be significantly associated with increased risk of breast cancer (p=0.04; 0.0064). Conclusions: The findings of the present study indicated significant associations of VEGF +936C>T and +405C>G polymorphisms with increased breast cancer risk in patients from Punjab, North India.

• BMB Reports
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• 제49권3호
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• pp.191-196
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• 2016

Vascular endothelial growth factor (VEGF) is a key mediator of angiogenesis and critical for normal embryonic development and repair of pathophysiological conditions in adults. Although phospholipase D (PLD) activity has been implicated in angiogenic processes, its role in VEGF signaling during angiogenesis in mammals is unclear. Here, we found that silencing of PLD2 by siRNA blocked VEGF-mediated signaling in immortalized human umbilical vein endothelial cells (iHUVECs). Also, VEGF-induced endothelial cell survival, proliferation, migration, and tube formation were inhibited by PLD2 silencing. Furthermore, while Pld2-knockout mice exhibited normal development, loss of PLD2 inhibited VEGF-mediated ex vivo angiogenesis. These findings suggest that PLD2 functions as a key mediator in the VEGF-mediated angiogenic functions of endothelial cells.