• BMB Reports
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• v.47 no.10
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• pp.581-586
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• 2014

Epidermal growth factor (EGF) is known to play key roles in skin regeneration and wound-healing. Here, we demonstrate that Pep2-YAC, a tripeptide covering residues 29-31 in the B loop of EGF, promotes the proliferation of HaCaT keratinocytes with activity comparable to EGF. The treatment of HaCaT cells with Pep2-YAC induced phosphorylation, internalization, and degradation of EGFR and organization of signaling complexes, which consist of Grb2, Gab1, SHP2, and PI3K. In addition, it stimulated the phosphorylation of ERK1/2 at Thr 202/Tyr 204 and of Akt1 at Ser 473 and the nuclear translocation of EGFR, STAT3, c-Jun, and c-Fos. These results suggest that Pep2-YAC may be useful as a therapeutic agent for skin regeneration and wound-healing as an EGFR agonist.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.4879-4881
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• 2012

Epidermal growth factor receptor (EGFR) overexpression is associated with resistance to chemotherapy and radiotherapy. The EGFR modulates DNA repair after radiation-induced damage through an association with the catalytic subunit of DNA protein kinase. DNA double-strand breaks (DSBs) are the most lethal type of DNA damage induced by ionizing radiation, and non-homologous end joining is the predominant pathway for repair of radiation-induced DSBs. Some cell signaling pathways that respond to normal growth factors are abnormally activated in human cancer. These pathways also invoke the cell survival mechanisms that lead to resistance to radiation. The molecular connection between the EGFR and its control over DNA repair capacity appears to be mediated by one or more signaling pathways downstream of this receptor. The purpose of this mini-review was not only to highlight the relation of the EGFR signal as a regulatory mechanism to DNA repair and radiation resistance, but also to provide clues to improving existing radiation resistance through novel therapies based on the above-mentioned mechanism.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.590-597
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• 2013

Principle component and emission localization of volatile compounds were investigated according to scent intensity of rose flower. Scent intensity in cultivars and bred-line of Rosa hybrida was divided into three levels; light ('Feel Lip', 'Venus Berry'), medium ('GR07-135'), strong ('Honey Blue'). The major volatile compounds were different depending on the cultivars and selected line; 3,5-dimethoxytoluene (DMT), benzene, 1,3,5-trimethoxy ('Feel Lip'), megastigma-4,6(Z),8(E)-triene ('Venus Berry'), DMT, benzene,1-ethenyl-4-methoxyand, phenylethylalcohol ('GR07-135') and germacrene-D, DMT ('Honey Blue'). The adaxial epidermal cells were conical papillate shape, whereas the abaxial epidermal cells were flat shape. The adaxial epidermal cells of 3 cultivars and 1 selected line were surrounded by thick cell wall and covered by waxy cuticle of 2 cultivars and 1 selected line (except 'Honey Blue'). The adaxial epidermal cells contained starches in 'Feel Lip', osmiophlic droplets in 'Venus Berry', starchs, plastids, vacuoles in 'GR07-135' and plastoglobules, plastids, vacuoles in 'Honey Blue'. Based on these results, it appears that plastids and vacuoles in adaxial epidermal cells with conical papillate shape are associated production and emission of volatile compounds in scent R. hybrida.

• Journal of Periodontal and Implant Science
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• v.26 no.4
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• pp.841-858
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• 1996

Epidermal growth factor(EGF) is one of polypeptide growth factors. EGF has been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. The purposes of this study is to evaluate the effects of EGF on the human periodontal ligament cells and human gingival fibroblast cells that promote regeneration of periodntal tissue. The mitogenic effects of epidermal growth factor on human periodontal ligament cells and human gingival fibroblasts were evaluated by determining the incorporation of 5-Bromo-2'-deoxy-uridine into DNA of the cells in a dose dependent manner. The prepared cells were the primary cultured gingival fibroblast and periodontal ligament cells from humans, the fourth or sixth subpassages were used in the experiments. Cells were seeded in DMEM containing 10% FBS. 1, 10, 50, 100, $200{\eta}g/ml$ and epidermal growth factor were added to the quiescent cells for 24 hours, 48 hours and 72 hours. They were labeled with $10\{mu}l/200{\mu}l$ 5-Bromo-2'-deoxy-uridine for the last 6 hours of each culture. The results of the five determinants were presented as mean and S.D.. The results were as follows : The DNA synthetic activity of human gingival fibroblasts were increased dose dependently by epidermal growth factor at 24 hours, 48 hours and 72 hours. The mitogenic effects were similar at the 24 and 48 hours of epidermal growth factor, but the DNA synthetic activity of human gingival fibroblasts generally decreased at 72 hours. The DNA synthetic activity of human periodontal ligament cells were increased dose dependently by epidermal growth factor at 24 hours but the DNA synthetic activity decreased at $200{\eta}g/ml$ of each hour. Generally the maximum mitogenic effects were observed at the 48 hours application of epidermal growth factor. The DNA synthetic activity of human periodontal ligament cells generally decreased lower at 24, 72 hours than at 48 hours the application of epidermal growth factor. In the comparison of DNA synthetic activity between human gingival fibroblasts and human periodontal ligament cells, human periodontal ligament cells had slightly higher proliferation activity than human gingival fibroblasts for a longer time at the high dosage of the epidermal growth factor. In conclusion, epidermal growth factor have important roles in the stimulation of DNA synthesis in human periodontal ligament cells and human gingival fibroblasts, and thus may be useful for clinical applications in periodontal regenerative procedures.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4265-4269
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• 2015

Introduction: The aim of the study was to explore the distribution of eyelid tumors in Ankara, the capital city of Turkey, from a histopathological point of view. Materials and Methods: Medical records of 1,502 patients who had eyelid surgery because of tumoral lesions were retrospectively reviewed after obtaining institutional review board approval. A total of 1,541 lesions with histopathologic diagnosis were included. Inflammatory tumoral lesions were excluded. The lesions were categorized into three groups according to the origin: epidermal, adnexal tumors and 'others', including melanocytic, neural and vascular lesions. Results: Of the total of 1,541, 908 lesions were epidermal in origin. Only 22 (1.5%) were malignant, and 6.0% was premalignant lesions such as actinic keratosis and Bowen's disease. Twenty-one of 22 malignant lesions were basal cell carcinoma. There was only one patient with squamous cell carcinoma and no sebaceous cell carcinoma. Among the benign tumors (92.5%), squamous papilloma was the most frequent (21.8% of all lesions). The other frequent lesions were nevus (17.6%), seborrheic keratosis (17.3%), hydrocystomas (10.6%), xanthelasma (7.6%) and epidermal cysts (7.2%). Conclusions: The results of this study are in accordance with published literature. The absence of sebaceous cell carcinomas needs to be stressed.

• International Journal of Oral Biology
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• v.43 no.3
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• pp.161-169
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• 2018

We previously demonstrated that epidermal growth factor (EGF) enhances cell migration and invasion of breast cancer cells in a SMAD ubiquitination regulatory factor 1 (SMURF1)-dependent manner and that SMURF1 induces degradation of ${\beta}-catenin$ in C2C12 cells. However, the relationship between EGF-induced SMURF1 and ${\beta}-catenin$ expression in breast cancer cells remains unclear. So, we investigated if EGF and SMURF1 regulate ${\beta}-catenin$ expression in MDAMB231 human breast cancer cells. When MDAMB231 cells were incubated with EGF for 24, 48, and 72 hours, EGF significantly increased expression levels of SMURF1 mRNA and protein while suppressing expression levels of ${\beta}-catenin$ mRNA and protein. Overexpression of SMURF1 downregulated ${\beta}-catenin$ mRNA and protein, whereas knockdown of SMURF1 increased ${\beta}-catenin$ expression and blocked EGF-induced ${\beta}-catenin$ downregulation. Knockdown of ${\beta}-catenin$ enhanced cell migration and invasion of MDAMB231 cells, while ${\beta}-catenin$ overexpression suppressed EGF-induced cell migration and invasion. Furthermore, knockdown of ${\beta}-catenin$ enhanced vimentin expression and decreased cytokeratin expression, whereas ${\beta}-catenin$ overexpression decreased vimentin expression and increased cytokeratin expression. These results suggest that EGF downregulates ${\beta}-catenin$ in a SMURF1-dependent manner and that ${\beta}-catenin$ downregulation contributes to EGF-induced cell migration and invasion in MDAMB breast cancer cells.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.477-484
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• 1994

Using a methylotrophic yeast Hansenula polymorpha, a heterologous gene expression and secretion system was developed for the production of hEGF(human Epidermal Growth Factor) which has been shown to promote epithelial cell proliferation and to inhibit gastric acid secretion. The hEGF gene was chemically synthesized according to the preferred codon usage in H. polymor- pha and expressed under the control of the strong and inducible methanol oxidase(MOX) promoter. The mating factor $\alpha$ pre-pro leader sequence of Saccharomyces cerevisiae was employed for hEGF to be secreted into the extracellular medium. This expression cassette was stably integrated into the host chromosomal DNA. Mature hEGF was efficiently expressed and secreted into the extracel- lular medium. About 24 mg/l of hEGF was detected in the cuture supernatant of a transformant with pA-EGF3 under the suboptimal culture conditions.

• Tuberculosis and Respiratory Diseases
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• v.75 no.5
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• pp.188-198
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• 2013

Over the past decade, several kinase inhibitors have been approved based on their clinical benefit in cancer patients. Unfortunately, in many cases, patients develop resistance to these agents via secondary mutations and alternative mechanisms. To date, several major mechanisms of acquired resistance, such as secondary mutation of the epidermal growth factor receptor (EGFR) gene, amplification of the MET gene and overexpression of hepatocyte growth factor, have been reported. This review describes the recent findings on the mechanisms of primary and acquired resistance to EGFR tyrosine kinase inhibitors and acquired resistance to anaplastic lymphoma kinase inhibitors, primarily focusing on non-small cell lung carcinoma.

• Archives of Pharmacal Research
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• v.26 no.8
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• pp.649-652
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• 2003

Polymeric nanoparticles composed of polystyrene (PS) as core and poly(methacrylic acid) (PMA) as corona were prepared by the dispersion copolymerization. The potential of the nanoparticles as carriers for recombinant human epidermal growth factor (EGF) was investigated. The nanoparticles showed monodispersity and good water-dispersibility. The loading content of EGF to the nanoparticles was very high due to electrostatic interaction between EGF and nanoparticles. EGF was released as a pseudo-zero order pattern after initial burst effect. The nanoparticles were sufficient for A431 cells proliferation.

• Journal of Yeungnam Medical Science
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• v.33 no.1
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• pp.64-67
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• 2016

We report on a 64-year-old man with leptomeningeal metastasis (LM) from an epidermal growth factor receptor (EGFR)-mutated adenocarcinoma of the lung. He was treated with paclitaxel, cisplatin. After completion of chemotherapy, he complained of headache, nausea, and vomiting. EGFR-mutated tumor cells were identified from the cerebrospinal fluid (CSF). Second-line therapy with gefitinib, methotrexate was started. After receiving gefitinib for 4 weeks, he had no more headaches or vomiting. Eleven months after initiation of gefitinib, he developed headache and nausea. Chest computed tomography showed aggravation of bone metastasis. Third-line therapy was started with gemcitabine and carboplatin. Two weeks later, he experienced disorientation. After a fourth relapse within the central nervous system, the therapy was switched to erlotinib and significant improvement of LM was achieved. This case shows that LM can be diagnosed by detecting EGFR mutation in CSF and EGFR tyrosine kinase inhibitors are effective for LM from EGFR mutant non-small cell lung cancer.