• Journal of Korean Neurosurgical Society
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• v.62 no.6
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• pp.626-634
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• 2019

Objective : Nerve growth factor (NGF) is a member of the neurotrophic factor family and plays a vital role in the physiological processes of organisms, especially in the nervous system. Many recent studies have reported that NGF is also involved in the regulation of tumourigenesis by either promoting or suppressing tumor growth, which depends on the location and type of tumor. However, little is known regarding the effect of NGF on interspinal schwannoma (IS). In the present study, we aimed to explored whether mouse nerve growth factor (mNGF), which is widely used in the clinic, can influence the growth of interspinal schwannoma cells (ISCs) isolated from IS in vitro. Methods : ISCs were isolated, cultured and identified by S-100 with immunofluorescence analysis. S-100-positive cells were divided into five groups, and separately cultured with various concentrations of mNGF (0 [phosphate buffered saline, PBS], 40, 80, 160, and 320 ng/mL) for 24 hours. Western blot and quantantive real time polymerase chain reaction (PCR) were applied to detect tyrosine kinase A (TrkA) receptor and p75 neurotrophin receptor ($p75^{NTR}$) in each group. Crystal violet staining was selected to assess the effect of mNGF (160 ng/mL) on ISCs growth. Results : ISCs growth was enhanced by mNGF in a dose-dependent manner. The result of crystal violet staining revealed that it was significantly strengthened the cells growth kinetics when cultured with 160 ng/mL mNGF compared to PBS group. Western blot and quantantive real time PCR discovered that TrkA receptor and mRNA expression were both up-regualated under the condition of mNGF, expecially in 160 ng/mL, while the exoression of $p75^{NTR}$ demonstrated no difference among groups. Conclusion : From these data, we conclude that exogenous mNGF can facilitate ISC growth by activating both TrkA receptor and $p75^{NTR}$. In addition, patients who are suffering from IS should not be administered mNGF in the clinic.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.5
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• pp.444-450
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• 2005

Epidermal growth factor (EGF) activates many intracellular effector molecules, which subsequently influence the expression levels of many genes involved in cell growth, apoptosis and signal transduction, etc. In this study, the early response of gene expressions due to EGF treatment was monitored using oligonucleotide DNA microarrays in rat schwannoma cell lines. An immunoblotting experiment showed the successful activation of EGF receptors and an effector protein, STAT5, due to EGF treatment. The microarray study showed that 35 genes were significantly induced and 2 were repressed within 60 min after the treatment. The list of induced genes included early growth response 1, suppressor of cytokine signaling 3, c-fos, interferon regulatory factor 1 and early growth response 2, etc. According to the microarray data, six of these were induced by more than 10-fold, and showed at least two different induction patterns, indicating complicated regulatory mechanisms in the EGF signal transduction.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.247-268
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• 1996

It has been known for a long time that gonadotropins and steroid hormones play a pivotal role in a series of reproductive biological phenomena including the maturation of ovarian follicles and oocytes, ovulation and implantation, maintenance of pregnancy and fetal growth & development, parturition and mammary development and lactation. Recent investigations, however, have elucidated that in addition to these classic hormones, multiple growth factors also are involved in these phenomena. Most growth factors in reproductive organs mediate the actions of gonadotropins and steroid hormones or synergize with them in an autocrine/paracrine manner. The insulin-like growth factor(IGF) system, which is one of the most actively investigated areas lately in the reproductive organs, has been found to have important roles in a wide gamut of reproductive phenomena. In the present communication, published literature pertaining to the intrauterine IGF system will be reviewed preceded by general information of the IGF system. The IGF family comprises of IGF-I & IGF-II ligands, two types of IGF receptors and six classes of IGF-binding proteins(IGFBPs) that are known to date. IGF-I and IGF-II peptides, which are structurally homologous to proinsulin, possess the insulin-like activity including the stimulatory effect of glucose and amino acid transport. Besides, IGFs as mitogens stimulate cell division, and also play a role in cellular differentiation and functions in a variety of cell lines. IGFs are expressed mainly in the liver and messenchymal cells, and act on almost all types of tissues in an autocrine/paracrine as well as endocrine mode. There are two types of IGF receptors. Type I IGF receptors, which are tyrosine kinase receptors having high-affinity for IGF-I and IGF-II, mediate almost all the IGF actions that are described above. Type II IGF receptors or IGF-II/mannose-6-phosphate receptors have two distinct binding sites; the IGF-II binding site exhibits a high affinity only for IGF-II. The principal role of the type II IGF receptor is to destroy IGF-II by targeting the ligand to the lysosome. IGFs in biological fluids are mostly bound to IGFBP. IGFBPs, in general, are IGF storage/carrier proteins or modulators of IGF actions; however, as for distinct roles for individual IGFBPs, only limited information is available. IGFBPs inhibit IGF actions under most in vitro situations, seemingly because affinities of IGFBPs for IGFs are greater than those of IGF receptors. How IGF is released from IGFBP to reach IGF receptors is not known; however, various IGFBP protease activities that are present in blood and interstitial fluids are believed to play an important role in the process of IGF release from the IGFBP. According to latest reports, there is evidence that under certain in vitro circumstances, IGFBP-1, -3, -5 have their own biological activities independent of the IGF. This may add another dimension of complexity of the already complicated IGF system. Messenger ribonucleic acids and proteins of the IGF family members are expressed in the uterine tissue and conceptus of the primates, rodents and farm animals to play important roles in growth and development of the uterus and fetus. Expression of the uterine IGF system is regulated by gonadal hormones and local regulatory substances with temporal and spatial specificities. Locally expressed IGFs and IGFBPs act on the uterine tissue in an autocrine/paracrine manner, or are secreted into the uterine lumen to participate in conceptus growth and development. Conceptus also expresses the IGF system beginning from the peri-implantation period. When an IGF family member is expressed in the conceptus, however, is determined by the presence or absence of maternally inherited mRNAs, genetic programming of the conceptus itself and an interaction with the maternal tissue. The site of IGF action also follows temporal (physiological status) and spatial specificities. These facts that expression of the IGF system is temporally and spatially regulated support indirectly a hypothesis that IGFs play a role in conceptus growth and development. Uterine and conceptus-derived IGFs stimulate cell division and differentiation, glucose and amino acid transport, general protein synthesis and the biosynthesis of mammotropic hormones including placental lactogen and prolactin, and also play a role in steroidogenesis. The suggested role for IGFs in conceptus growth and development has been proven by the result of IGF-I, IGF-II or IGF receptor gene disruption(targeting) of murine embryos by the homologous recombination technique. Mice carrying a null mutation for IGF-I and/or IGF-II or type I IGF receptor undergo delayed prenatal and postnatal growth and development with 30-60% normal weights at birth. Moreover, mice lacking the type I IGF receptor or IGF-I plus IGF-II die soon after birth. Intrauterine IGFBPs generally are believed to sequester IGF ligands within the uterus or to play a role of negative regulators of IGF actions by inhibiting IGF binding to cognate receptors. However, when it is taken into account that IGFBP-1 is expressed and secreted in primate uteri in amounts assessedly far exceeding those of local IGFs and that IGFBP-1 is one of the major secretory proteins of the primate decidua, the possibility that this IGFBP may have its own biological activity independent of IGF cannot be excluded. Evidently, elucidating the exact role of each IGFBP is an essential step into understanding the whole IGF system. As such, further research in this area is awaited with a lot of anticipation and attention.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.300-308
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• 2000

The Fibroblast growth factors(FGFs) plays an important role in the control of osteogenesis during skeletal development. Especially, FGF-2 is a potent mesodermal inducer during embryogenesis and FGF receptors (FGFRs) messages are strongly expressed in developing bones. In this study, we investigated the effect of bFGF on osteopontin(OPN) gene expression in ST-2 cells and tried to elucidate the mechanism of its stimulatory effects. The obtain results were as follows; The treatment of bFGF(1ng/ml) upregulates OPN, fibronectin mRNA levels and downregulates type I collagen mRNA levels. But, there was no remarkable difference in alkaline phosphatase mRNA levels between two groups. The OPN gene expression increased in a dose-dependent manner up to 10ng/ml and OPN gene began to occur at around 3h with continuous increase up to 24h then decreased to basal level at 48h. 30 minutues pretreatment with cycloheximide (500ng/ml), a protein synthesis inhibitor, prior to addition bFGF resulted in blocking bFGF induced OPN expression. These results suggest that bFGF increased the level of OPN mRNA in a dose and time-dependent manner via the synthesis of certain transcriptional regulatory proteins.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.34-36
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• 2002

Epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) have been shown to stimulate proliferation and differentiation of various somatic cells, including placental trophoblasts and also to enhance fetal growth and development when maternally administered. Since an increase of the expression of placental EGF and IGF-I receptors in rat, mouse, and human with the gestation advanced, both EGF and IGF-I were considered to play pivotal roles on fetal growth by regulating some function of placental cells. Amino acids are crucial importance for both maternal and fetal requirements of energy source and essential constituent of fetal mass during pregnancy. Impaired fetal and placental uptake of amino acids has been observed in several models of growth retardation in the rat. Amino acid is concentrated in the fetal side through active transport by amino acid transporters and is one of the important metabolic fuels for the fatal growth. Therefore, at first plasma amino acid concentrations in mothers and fetuses were measured as an index of uphill transport across the placenta associated with EGF and IGF-1. The EGF administration at the concentration of 0, 0.1, or 0.2 $\mu\textrm{g}$/g to pregnant rats from day 18 to 21 of gestation apparently increased fetal/maternal ratio of serum proline concentration and also fatal growth in EGF dose-dependent manner. When IGF-I in doses of 0, 1, 2, and 4 $\mu\textrm{g}$/g were administrated, the ratio of leucine, isoleucine, tryptophan, phenylalanine, tyrosine and also fetal growth significantly increased with a dose-dependent manner. These results suggested that EGF and IGF-I enhanced fatal growth by, as one of its possible mechanisms, promoting placental activity to transfer some amino acid supplies from the mother to the fetus in late pregnancy.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.3
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• pp.496-502
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• 2011

The present study was undertaken to investigate the effect of bee venom acupuncture therapy on the hair follicle growth by macroscopic, microscopic and immunohistochemical observation of skin 10 and 17 days after treatment. The results were as follows : Macroscopic hair follicle growth of 0.2 ml S.B.V. acupuncture treated group was more prominent than those of 0.1 ml S.B.V. acupuncture treated group and control group. Microscopic observation indicated that the hair follicle growth of control group reached anagen phase IV of hair growing cycle, and that of 0.1 ml and 0.2 ml S.B.V. acupuncture treated groups reached anagen phase VI and catagen, respectively. Immunohistochemical observations of the expression of various cytokines, enzymes and receptors in association with hair follicle cycle after local treatment of S.B.V. acupuncture therapy are as follows: Expression of fibroblast growth factor was more intense in epidermis and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of 0.1 ml S.B.V. acupuncture treated group and control group. Expression of epidermal growth factor was more intense in bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of 0.1 ml S.B.V. acupuncture treated group and control group. Expression of c-kit receptor was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of control group. Expression of vascular endothelial growth factor was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of control group. Expression of protein kinase C-${\alpha}$ was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than control group. It is concluded that bee venom acupuncture therapy promoted the expression of various cytokines, enzymes and receptors related to the hair growth cycle for hair growth. This findings indicates that bee venom acupuncture therapy is applicable to the treatment of hair loss.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.4
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• pp.281-289
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• 2019

Vascular endothelial growth factor (VEGF)-C and its receptor, vascular endothelial growth factor receptor (VEGFR)-3, are responsible for lymphangiogenesis in both embryos and adults. In epilepsy, the expression of VEGF-C and VEGFR-3 was significantly upregulated in the human brains affected with temporal lobe epilepsy. Moreover, pharmacologic inhibition of VEGF receptors after acute seizures could suppress the generation of spontaneous recurrent seizures, suggesting a critical role of VEGF-related signaling in epilepsy. Therefore, in the present study, the spatiotemporal expression of VEGF-C and VEGFR-3 against pilocarpine-induced status epilepticus (SE) was investigated in C57BL/6N mice using immunohistochemistry. At 1 day after SE, hippocampal astrocytes and microglia were activated. Pyramidal neuronal death was observed at 4 days after SE. In the subpyramidal zone, VEGF-C expression gradually increased and peaked at 7 days after SE, while VEGFR-3 was significantly upregulated at 4 days after SE and began to decrease at 7 days after SE. Most VEGF-C/VEGFR-3-expressing cells were pyramidal neurons, but VEGF-C was also observed in some astrocytes in sham-manipulated animals. However, at 4 days and 7 days after SE, both VEGFR-3 and VEGF-C immunoreactivities were observed mainly in astrocytes and in some microglia of the stratum radiatum and lacunosum-moleculare of the hippocampus, respectively. These data indicate that VEGF-C and VEGFR-3 can be upregulated in hippocampal astrocytes and microglia after pilocarpine-induced SE, providing basic information about VEGF-C and VEGFR-3 expression patterns following acute seizures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.2
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• pp.66-73
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• 2009

Tumor angiogenesis is a process leading to formation of blood vessels within tumors and is crucial for maintaining a supply of oxygen and nutrients to support tumor growth and metastasis. Vascular endothelial growth factor(VEGF) plays a key role in tumor angiogenesis including induction of endothelial cell proliferation, migration, survival and capillary tube formation. VEGF binds to two distinct receptors on endothelial cells. VEGFR-2 is considered to be the dominant signaling receptor for endothelial cell permeability, proliferation, and differentiation. Bevacizumab(Avastin, Genetech, USA) is a monoclonal antibody against vascular endothelial growth factor. It is used in the treatment of cancer, where it inhibits tumor growth by blocking the formation of new blood vessels. The goal of this study is to identify the anti-tumor effect of Bevacizumab(Avastin) for oral squamous cell carcinoma cell lines. Human squamous cell carcinoma cell line(HN4) was used in this study. We examined the sensitivity of HN4 cell line to Bevacizumab(Avastin) by using in vitro proliferation assays. The results were as follows. 1. In the result of MTT assay according to concentration of Bevacizumab(Avastin), antiproliferative effect for oral squamous cell carcinoma cell lines was observed. 2. The growth curve of cell line showed the gradual growth inhibition of oral squamous cell carcinoma cell lines after exposure of Bevacizumab(Avastin). 3. In the apoptotic index, groups inoculated Bevacizumab(Avastin) were higher than control groups. 4. In condition of serum starvation, VEGFR-2 did not show any detectable autophosphorylation, whereas the addition of VEGF activated the receptor. Suppression of phosphorylated VEGFR-2 and phosphorylated MAPK was observed following treatment with Bevacizumab(Avastin) in a dose-dependent manner. 5. In TEM view, dispersed nuclear membrane, scattered many cytoplasmic vacuoles and localized chromosomal margination after Bevacizumab(Avastin) treatment were observed. These findings suggest that Bevacizumab(Avastin) has the potential to inhibit MAPK pathway in proliferation of oral squamous cell carcinoma cell lines via inhibition of VEGF-dependent tumor growth.

• BMB Reports
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• v.44 no.12
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• pp.772-781
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• 2011

Branched N-glycans are produced by a series of glycosyltransferases including N-acetylglucosaminyltransferases and fucosyltransferases and their corresponding genes. Glycans on specific glycoproteins, which are attached via the action of glycosyltransferases, play key roles in cell adhesion and signaling. Examples of this are adhesion molecules or signaling molecules such as integrin and E-cadherin, as well as membrane receptors such as the EGF and TGF-${\beta}$ receptors. These molecules also play pivotal roles in the underlying mechanism of a variety of disease such as cancer metastasis, diabetes, and chronic obstructive pulmonary disease (COPD). Alterations in the structures of branched N-glycans are also hall marks and are useful for cancer biomarkers and therapeutics against cancer. This mini-review describes some of our recent studies on a functional glycomics approach to the study of branched N-glycans produced by N-acetylglucosaminyltransferases III, IV, V and IX (Vb) (GnT-III, GnT-IV, V and IX (Vb)) and fucosyltransferase 8 (Fut8) and their pathophysiological significance, with emphasis on the importance of a systems glycobiology approach as a future perspective for glycobiology.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.1-8
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• 1999

Transforming growth factor-$\beta$ (TGF-$\beta$) is the prototypical multifunctional cytokine, participating in the regulation of vital cellular activities such as proliferation and differentiations as well as a number of basic physiological functions. The effects of TGF-$\beta$ are critically dependent on the expression and distribution of a family of TGF-$\beta$ receptors, the TGF-$\beta$ types I, II, and III. It is now known that a wide variety of human pathology can be caused by aberrant expression and function of these receptors. the coding sequence of the type II receptor (RII) appears to render it uniquely susceptible to DNA replication errors in the course of normal cell division. By virtue of its key role in the regulation of cell proliferation, TGF-$\beta$ RII should be considered as a tumor suppressor gene. High levels of mutation in the TGF-$\beta$ RII gene have been observed in a wide range of primarily epithelial malignancies, including colon and gastric cancer. It appears likely that mutation of the TGF-$\beta$ RII gene may be a very critical step in the pathway of carcinogenesis.