• 대한생식의학회:학술대회논문집
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• 대한불임학회 2003년도 제45차 추계학술대회
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• pp.124-125
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• 2003

• 생명과학회지
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• 제34권2호
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• pp.128-137
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• 2024

이 리뷰 논문에서는 혈관 투과성, 내피세포 모집, 종양관련 혈관 및 림프관의 유지 등에서 핵심적인 과정인 angiogenesis와 lymphangiogenesis에 있어서 vascular endothelial growth factors (VEGF)가 이행하는 중요한 역할에 대해 재조명하고자 한다. VEGF는 tyrosine-kinase receptor인 VEGFR-1, VEGFR-2, VEGFR-3를 통해 그 역할을 이행하며, 이러한 VEGF-VEGFR 시스템은 암에서뿐만 아니라 비정상적인 혈관 및 림프관 형성으로 인해 야기되는 다른 질병들에 있어서도 핵심적인 요소로 각광받고 있다. 암의 측면에서 보았을 때, VEGF와 그 수용체는 종양관련 혈관 및 림프관을 형성하는 과정에서 필수적이라는 점에서 치료적인 타겟으로 이목을 끌고 있다. 때문에 암세포의 성장을 방해하기 위한 항VEGF 항체, 수용체 길항체, 수용체 기능 억제제 등과 같은 여러 가지 시도들이 있었지만, 아직까지 그 임상효과가 불확실하며 더 많은 연구들이 필요한 실정이다. 이 논문에서는 VEGF의 생리적 역할을 VEGF-A, VEGF-B, VEGF-C, VEGF-D, PLGF에 따라 나누어 설명하면서 VEGF/VEGFR 시스템의 중요성을 강조한다. VEGFR-1과 VEGFR-3은 각각 angiogenesis와 lymphangiogenesis에 핵심적인 인자이며, VEGFR-2의 경우 두 가지 모두를 일으킨다. 전반적으로 이 리뷰는 현재까지 밝혀진 암을 포함한 다양한 질병에서의 VEGF와 VEGFR의 역할에 대해 상세히 설명하고자 하였다. 이를 통해 치료 표적으로서 VEGF와 VEGFR의 활용이 더욱 촉진될 것으로 기대된다.

• Journal of Korean Neurosurgical Society
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• 제29권10호
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• pp.1303-1308
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• 2000

Objectives : It has been known that vascular endothelial growth factor(VEGF), as an endothelial cell-specific mitogen, induces angiogenesis, and possesses vascular permeability and procoagulant properties. Peritumoral brain edema(PTBE) is a common accompaniment of malignant gliomas. It results from microvascular extravasation of plasma and proteins through the interendothelial spaces. The correlation between pathological grading, PTBE, neovascularization, and the expression of VEGF were analyzed in 31 patients with astrocytic tumors. Methods : Astrocytic tumor samples(8 astrocytomas, 14 anaplastic astrocytomas, and 9 glioblastomas) from 31 patients( 21 males and 10 females : average age $37{\pm}24$ years) who underwent surgery were examined retrospectively for the expression of VEGF and CD31(microvasculature) immunohistochemically. The extent of PTBE was examined by using preoperative CT or MRI as an edema index(EI). In addition to VEGF and CD31, several causative factors including tumor size, histologic type were compared with EI. Results : Only one of 8 astrocytomas, and majority of high grade(21 of 23 anaplastic astrocytomas and glioblastomas) tumors demonstrated PTBE(p<0.05). The majority of high grade tumors showed higher expression of VEGF (p<0.01). High grade tumors showed even higher CD31 expression(p<0.05), however, there was no close correlation between expression of VEGF and CD31. The EI was increased significantly, just as VEGF(p<0.01), but CD31 expression was not correlated with high EI. Conclusion : These data suggest that VEGF expression is closely correlated with PTBE and histological grading in astrocytic tumors. Microvasculature(CD31) in tumors is highly correlated with histological grading, however, shows no correlation with the expression of VEGF and PTBE.

• Journal of Applied Biological Chemistry
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• 제48권4호
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• pp.178-182
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• 2005

Nitric oxide (NO) produced from endothelial cells plays a critical role in vascular physiology. The regulation of endothelial NO synthase (eNOS) involves various mechanisms including multiple Ser/Thr phosphorylations. Recently, eNOS-Ser617 was newly recognized to be phosphorylated in response to humoral factors including vascular endothelial growth factor. However, it remains unknown whether and how eNOS-Ser617 phosphorylation is stimulated by shear stress, the primary stimulus of endothelial NO production. This issue was explored in the present study using cultured bovine aortic endothelial cells (BAECs). Over-expression of a constitutively active protein kinase B(Akt) mutant in BAECs increased Ser617 phosphorylation while constitutively active protein kinase A mutant had no effect. When BAECs were subjected to an arterial level of laminar shear stress, eNOS-Ser617 phosphorylation was clearly increased in a time-dependent manner. Shear stress also stimulated Akt phosphorylation at Thr308, one of the key regulatory sites. The time courses of eNOS-Ser617 and Akt-Thr308 phosphorylations appeared to be very similar. These results suggested that eNOS-Ser617 phosphorylation, mediated by Akt, is a physiological response to the mechanical shear stress, involved in the regulation of NO production in endothelial cells.

• Journal of Korean Neurosurgical Society
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• 제29권12호
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• pp.1584-1591
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• 2000

Objective : Until now, it has been little known about the biological mechanisms associated with the genesis, growth, and rupture of intracranial aneurysm. This study was performed to investigate and understand a part of these mechanisms. Materials and Methods : Immunohistochemical stains for angiogenesis growth factors(basic fibroblast growth factor (bFGF) and vascular endothelial growth factor(VEGF)) and selected vascular wall matrix proteins(alpha smooth muscle actin(${\alpha}SMA$) and collagen Type IV) were performed in fixed sections from a normal circle of Willis artery which was taken from the autopsy specimen as a control vessel and 17 aneurysmal wall specimens which was taken during surgical clipping of aneurysms. The staining intensity and distribution of immunoreactivity to angiogenesis growth factors and selected wall matrix proteins in control vessel and aneurysmal wall were examined and compared with each other. The difference of staining intensity according to the size of aneurysm was also investigated. Results : There was no immunoreactivity to bFGF and VEGF in the control vessel. bFGF immunoreactivity was exhibited in 15 of 17 aneurysm specimens around smooth muscle cells within the media of aneurysm. VEGF immunoreactivity was also exhibited in all aneurysm specimens in patches or diffusely affecting all layers of the aneurysmal wall. The degrees of intensity of bFGF and VEGF immunoexpression were proportionate roughly to the size of aneurysm. Strong immunoexpression of both factors were noticed in large aneurysm. A regularly arranged and defined band of immunoreactivity of ${\alpha}SMA$ was noticed in the media of the control vessel, whereas diffuse, faint, irregularly arranged ${\alpha}SMA$ was noticed in the aneurysmal wall. A regularly defined band of collagen Type IV immunoreactivity was also noticed in the subendothelium of the control vessel, whereas diffuse disorganized immunoreactivity of collagen Type IV was noticed in the entire wall of the aneurysm. Conclusion : These results indicate substantial evidences of abnormal expression of angiogenesis factors and changes of selected vascular wall matrix proteins in the wall of intracranial aneurysm. The unbalanced changes of angiogenesis factors and vascular wall matrix proteins in the wall of aneurysm may be one of the biological mechanisms for the growth and rupture of aneurysm.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.337.2-337.2
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• 2002

Conjugated linoleic acid (CLA) is a potent inhibitor of mammary carcinogenesis. Cancer cells produce various angiogenic factors which stimulate host vascular endothelial cell mitogenesis and chemotaxis for their growth and metastasis. Basic fibroblast growth factor (bFGF) is a potent angiogenic factor that is expressed in many tumors. In this study. we found that CLA decreased bFGF-induced endothelial cell proliferation and DNA synthesis in a dose-dependent manner. However, CLA did not inhibit endothelial cell migration. Furthermore CLA showed a potent inhibitory effect on embryonic vasculogenesis and bF GF-induced angiogenesis in vivo. Collectively. these results suggest that CLA selectively inhibis the active proliferating endothelial edll induced by bFGF. which may explain its anti-carcinogenix properties in vivo.

• Journal of Ginseng Research
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• 제36권2호
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• pp.135-145
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• 2012

Previously, we reported that Helicobacter pylori-associated gastritis and gastric cancer are closely associated with increased levels of hydrogen sulfide ($H_2S$) and that Korean red ginseng significantly reduced the severity of H. pylori-associated gastric diseases by attenuating $H_2S$ generation. Because the incubation of endothelial cells with $H_2S$ has been known to enhance their angiogenic activities, we hypothesized that the amelioration of $H_2S$-induced gastric inflammation or angiogenesis in human umbilical vascular endothelial cells (HUVECs) might explain the preventive effect of Korean red ginseng on H. pylori-associated carcinogenesis. The expression of inflammatory mediators, angiogenic growth factors, and angiogenic activities in the absence or presence of Korean red ginseng extracts (KRGE) were evaluated in HUVECs stimulated with the $H_2S$ generator sodium hydrogen sulfide (NaHS). KRGE efficiently decreased the expression of cystathionine ${\beta}$-synthase and cystathionine ${\gamma}$-lyase, enzymes that are essential for $H_2S$ synthesis. Concomitantly, a significant decrease in the expression of inflammatory mediators, including cyclooxygenase-2 and inducible nitric oxide synthase, and several angiogenic factors, including interleukin (IL)-8, hypoxia inducible factor-1a, vascular endothelial growth factor, IL-6, and matrix metalloproteinases, was observed; all of these factors are normally induced after NaHS. An in vitro angiogenesis assay demonstrated that NaHS significantly increased tube formation in endothelial cells, whereas KRGE pretreatment significantly attenuated tube formation. NaHS activated p38 and Akt, increasing the expression of angiogenic factors and the proliferation of HUVECs, whereas KRGE effectively abrogated this $H_2S$-activated angiogenesis and the increase in inflammatory mediators in vascular endothelial cells. In conclusion, KRGE was able to mitigate $H_2S$-induced angiogenesis, implying that antagonistic action against $H_2S$-induced angiogenesis may be the mechanism underlying the gastric cancer preventive effects of KRGE in H. pylori infection.

• 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.

• 생명과학회지
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• 제24권4호
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• pp.337-342
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• 2014

Resveratrol (RSV)은 천연 폴리페놀계 화합물로 세포분열, 성장, 세포이동 등과 같은 다양한 효과가 보고되었다. Angiogenin (ANG)은 Vascular endothelial growth factor (VEGF)와 함께 세포의 증식, 신생혈관형성, tubular structures의 형성, 세포이동 등을 이끄는 중요한 단백질이다. 본 연구에서는 RSV에 의한 세포이동효과를 HeLa 세포에서 관찰하였다. Real-time PCR을 통해 HeLa 세포에 RSV $0{\sim}50{\mu}M$을 24시간 동안 처리하였을 때, 농도에 따른 ANG, VEGF 유전자 발현이 의미 있게 증가 하였다. 같은 방법으로, RSV $50{\mu}M$을 시간에 따라(0~48시간) 처리하여 실험하였다. 그 결과, RSV $50{\mu}M$을 24시간 동안 처리하였을 때 ANG, VEGF 유전자 발현이 가장 높게 증가하였고, ANG 단백질 분석에서도 동일한 결과를 얻었다. 또한, MTT assay를 이용한 세포 독성연구에서, RSV $50{\mu}M$의 농도에서는 영향을 미치지 않음을 관찰하여, 이를 최적의 조건으로 결정하였다. RSV가 처리된 세포에서 세포이동효과를 조사하기 위해 wound-healing assay를 수행하였다. RSV가 처리된 그룹에서 세포이동이 의미 있게 증가하였다. 따라서, 본 연구에는 RSV에 의해 ANG, VEGF의 발현이 증가했고, 이에 따라 세포이동이 향상됨을 관찰하였다.

• 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.