• Title/Summary/Keyword: EGFR protein

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Objective Quantitation of EGFR Protein Levels using Quantitative Dot Blot Method for the Prognosis of Gastric Cancer Patients

  • Xin, Lei;Tang, Fangrong;Song, Bo;Yang, Maozhou;Zhang, Jiandi
    • Journal of Gastric Cancer
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    • v.21 no.4
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    • pp.335-351
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    • 2021
  • Purpose: An underlying factor for the failure of several clinical trials of anti-epidermal growth factor receptor (EGFR) therapies is the lack of an effective method to identify patients who overexpress EGFR protein. The quantitative dot blot method (QDB) was used to measure EGFR protein levels objectively, absolutely, and quantitatively. Its feasibility was evaluated for the prognosis of overall survival (OS) of patients with gastric cancer. Materials and Methods: Slices of 2×5 ㎛ from formalin-fixed paraffin-embedded gastric cancer specimens were used to extract total tissue lysates for QDB measurement. Absolutely quantitated EGFR protein levels were used for the Kaplan-Meier OS analysis. Results: EGFR protein levels ranged from 0 to 772.6 pmol/g (n=246) for all gastric cancer patients. A poor correlation was observed between quantitated EGFR levels and immunohistochemistry scores with ρ=0.024 and P=0.717 in Spearman's correlation analysis. EGFR was identified as an independent negative prognostic biomarker for gastric cancer patients only through absolute quantitation, with a hazard ratio of 1.92 (95% confidence interval, 1.05-3.53; P=0.034) in multivariate Cox regression OS analysis. A cutoff of 208 pmol/g was proposed to stratify patients with a 3-year survival probability of 44% for patients with EGFR levels above the cutoff versus 68% for those below the cutoff based on Kaplan-Meier OS analysis (log rank test, P=0.002). Conclusions: A QDB-based assay was developed for gastric cancer specimens to measure EGFR protein levels absolutely, quantitatively, and objectively. This assay should facilitate clinical trials aimed at evaluation of anti-EGFR therapies retrospectively and prospectively for gastric cancer.

Clinical Significance of the Expression of p53, p21, EGFR and c-erbB-2 in Squamous Cell Carcinoma of the Head and Neck (두경부 편평세포암종에서 p53, p21, EGFR 및 c-erbB-2 발현의 임상적 의의)

  • Lee Jun-Han;Do Nam-Yong;Park Sung-Yong;Kim Gun-Hyung;Cho Sung-Il
    • Korean Journal of Head & Neck Oncology
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    • v.21 no.2
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    • pp.139-145
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    • 2005
  • Background and Objectives: Because of squamous cell carcinoma of the head and neck undergoes a generally poor hospital course, the prognostic significance of the squamous cell carcinomas in head and neck have been evaluated to identify those features associated with aggressive biologic behavior according to the immunologic and histopathologic characteristics. Materials and Method: To assess the significance of EGFR, c-erbB-2, p21 and p53 protein in head and neck tumors and their correlation with prognostic factors, samples from 74 patients with squamous cell carcinomas of larynx, pharynx, and oral cavity were studied immunohistochemically. Results: EGFR, c-erbB-2, p21, and p53 protein were expressed 94.6%, 24.3%, 85.1%, and 55.4% in 74 cases of head and neck squamous cell carcinoma, respectively. The positive expression of EGFR was associated significantly with clinical stage and the negative expressions of p21 was associated significantly with histopathologic differentiation. There were no significant relationships between the reactivity of EGFR, c-erbB-2, p21, and p53 protein. Conclusion: The expression of EGFR, c-erbB-2, p21 and p53 protein could be related to oncogenesis, and the expression of p21 and EGFR protein can be used as a prognosticator in head and neck squamous cell carcinoma under certain limitations, but c-erbB-2 and p53 protein expression alone is not enough for evaluating prognosis of the carcinoma.

Overexpression of EGFR Protein in Bruneian Lung Cancer Patients

  • Han, Yu Hao;Hamid, Mas R.W. Abdul;Telisinghe, Pemasiri Upali;Hussin, Juniadah Binti Haji;Mabruk, Mohamed
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.1
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    • pp.233-237
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    • 2015
  • Background: Lung cancer is the leading cause of cancer death in Brunei Darussalam, accounting for almost 20% of the total. The epidermal growth factor receptor (EGFR) is a member of the erbB family of tyrosine kinase receptor proteins, which includes c-erbb2(HER2/neu), erb-B3, and erb-B4. EGFR overexpression is found in a third of all epithelial cancers, often associated with a poor prognosis. Materials and Methods: Protein expression of EGFR in 27 cases of lung cancer tissue samples and 9 cases of normal lung tissue samples was evaluated using an immunohistochemical approach. Results: The results demonstrated significant increase and overexpression of EGFR in Bruneian lung cancer tissue samples in comparison to normal lung tissue. However, there was no significant relationship between clinicopathologic variables (age and sex) of patients and EGFR protein expression. Conclusions: EGFR is overexpressed in Bruneian lung cancer patient tissue samples in comparison to normal lung tissue samples. This may indicate that EGFR protein over expression plays an important role in the genesis of this type of cancer in Brunei Darussalam.

Signal Transduction of MUC5AC Expression in Airway Mucus Hypersecretory Disease (기도의 점액 과분비 질환에서 MUC5AC의 발현의 신호 전달 경로에 관한 연구)

  • Shim, Jae Jeong
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.1
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    • pp.21-30
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    • 2003
  • Background : Mucin synthesis in airways has been reported to be regulated by the epidermal growth factor receptor (EGFR) system. Epidermal growth factor receptor transactivation was identified as a critical element in G-protein-coupled receptors (GPCRs)-induced mitogenic signaling. EGF receptor transactivation by G-protein-coupled receptors requires metalloproteinase cleavage of proHB-EGF. This study was hypothesized that lipopolysaccharide (LPS)-induced mucin production associates with epidermal growth factor receptor transactivation, and MUC5AC production associates with epidermal growth factor receptor transactivation by G-protein-coupled receptors that regulates by metalloproteinase. Method : MUC5AC mucin production was examined in NCI-H292 cells and MUC5AC protein synthesis was assessed using ELISA. For the evaluation of mechanism of LPS-induced MUC5AC production, $TNF{\alpha}$ was measured using ELISA with or without pretreatment of heterotrimeric G-protein inhibitor, mastoparan. MUC5AC protein was measure with pretreatment of polyclonal $TNF{\alpha}$ antibody or mastoparan on LPS-induced MUC5AC production. For the evaluation of relation of G-protein and MUC5AC production, G-protein stimulant, mastopara-7, or matrix metalloproteinase, ADAM10, was added to NCI-H292 cells. MUC5AC protein was measure with pretreatment of polyclonal EGF antibody on mastoparan-7-induced MUC5AC production. Results : LPS alone did not increase significantly MUC5AC production. LPS with $TNF{\alpha}$ induced dose-dependently MUC5AC production in NCI-H292 cells. LPS increased dose-dependently $TNF{\alpha}$ secretion, which was inhibited by mastoparan. LPS with $TNF{\alpha}$-induced MUC5AC production was inhibited by neutralizing polyclonal $TNF{\alpha}$ antibody, mastoparan or AG 1472. Mastoparan-7 or ADAM10 increased dose-dependently MUC5AC production, which was inhibited by polyclonal neutralizing EGF antibody. Conclusion : In LPS-induced MUC5AC synthesis, LPS causes $TNF{\alpha}$ secretion, which induces EGFR expression. EGFR tyrosine kinase phosphorylation result in MUC5AC production. EGF-R transactivation by G-protein-coupled receptors requires matrix metalloproteinase cleavage of proHB-EGF.

Differential Expression of EGFR Protein by Immunohistochemical Staining Methods and the Relationship Between the Degree of EGFR Protein Expression and EGFR Gene Mutation (면역조직화학적 염색 방법에 따른 상피세포 성장 수용체 단백(EGFR)의 발현정도의 차이 및 EGFR의 발현정도와 EGFR 유전자의 돌연변이와의 상관관계에 대한 고찰)

  • Yoon, In-Sook;Kim, Keuk-Jun;Lee, Eun-Hwa;Seok, Sang-Hee;Kim, Sang-Hee;Kim, Hyun-Yong;Song, Ho-Jung;Lee, Tae-Jong
    • Korean Journal of Clinical Laboratory Science
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    • v.39 no.3
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    • pp.217-222
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    • 2007
  • In the last 5 years the Epidermal Growth Factor Receptor (EGFR) has emerged as one of the most important targets for drug development in oncology. Monoclonal antibodies targeting the external domain of EGFR have been shown to have clinical benefits in colorectal and head and neck cancer when combined with chemotherapy and/or radiation. Also the targeting of the epithelial growth factor receptor (EGFR) kinase domain using the closely related inhibitors gefitinib and erlotinib has generally been ineffective against solid tumors, many of which over express the receptor. We found that there were some differential expressions according to primary antibodies of the EGFR protein which being used as one of the histological tumor markers for non-small cell lung cancer (NSCLC). We also found that there are some differential expressions according to antibodies, the pH of the antigen retrieval (AR) buffer solutions and kinds of enzymes. There were some differential expressions according to the secondary antibodies and the detection systems. We analyzed the correlations between the immunohistochemical expressions of the EGFR protein and the gene mutations of the EGFR. The differences between automatic stainers and manual staining methods were also evaluated.

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Mutations in the tyrosine kinase domain of the EGFR gene are rare in the Korean Oral Squamous Cell Carcinoma

  • Lee, Eun-Ju
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.9
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    • pp.101-106
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    • 2016
  • The epidermal growth factor receptor(EGFR) protein kinase signaling is an important pathway in cancer development and recently reported that EGFR and its kinase domain molecules are mutated in various of cancers including head and neck cancer. Functional deregulation of EGFR due to mutations in coding exons and copy number amplification is the most common event in cancers, especially among receptor tyrosine kinases(TK). We have analyzed Korean oral squamous cell carcinomas (OSCC) cell lines for mutations in EGFRTK. Exons encoding the hot-spot regions in the TK domain of EGFR (exons 17 to 23) were amplified by using polymerase chain reaction(PCR) and sequenced directly. EGFR expression was also analyzed in 8 OSCC cell lines using western blotting. Data analysis of the EGFR exons 17 to 23 coding sequences did not show any mutations in the 8 OSCC cell lines that were analyzed. The absence of mutations indicate that protein overexpression might be responsible for activation rather than mutation.

A small molecule approach to degrade RAS with EGFR repression is a potential therapy for KRAS mutation-driven colorectal cancer resistance to cetuximab

  • Lee, Sang-Kyu;Cho, Yong-Hee;Cha, Pu-Hyeon;Yoon, Jeong-Soo;Ro, Eun Ji;Jeong, Woo-Jeong;Park, Jieun;Kim, Hyuntae;Kim, Tae Il;Min, Do Sik;Han, Gyoonhee;Choi, Kang-Yell
    • Experimental and Molecular Medicine
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    • v.50 no.11
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    • pp.12.1-12.12
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    • 2018
  • Drugs targeting the epidermal growth factor receptor (EGFR), such as cetuximab and panitumumab, have been prescribed for metastatic colorectal cancer (CRC), but patients harboring KRAS mutations are insensitive to them and do not have an alternative drug to overcome the problem. The levels of ${\beta}$-catenin, EGFR, and RAS, especially mutant KRAS, are increased in CRC patient tissues due to mutations of adenomatous polyposis coli (APC), which occur in 90% of human CRCs. The increases in these proteins by APC loss synergistically promote tumorigenesis. Therefore, we tested KYA1797K, a recently identified small molecule that degrades both ${\beta}$-catenin and Ras via $GSK3{\beta}$ activation, and its capability to suppress the cetuximab resistance of KRAS-mutated CRC cells. KYA1797K suppressed the growth of tumor xenografts induced by CRC cells as well as tumor organoids derived from CRC patients having both APC and KRAS mutations. Lowering the levels of both ${\beta}$-catenin and RAS as well as EGFR via targeting the $Wnt/{\beta}$-catenin pathway is a therapeutic strategy for controlling CRC and other types of cancer with aberrantly activated the $Wnt/{\beta}$-catenin and EGFR-RAS pathways, including those with resistance to EGFR-targeting drugs attributed to KRAS mutations.

Molecular docking to EGFR tyrosine kinase domain : Structural Validation against Crystal Structures

  • Jang, Jun-Yeong;Cho, Art E.
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.126-130
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    • 2016
  • Epidermal growth factor receptor(EGFR)는 HER family에 속하는 tyrosine kinase receptor로서 다양한 하류경로로 신호를 전달하여 세포 증식, 혈관 형성, 세포 사멸을 억제하는 역할을 한다. EGFR이 폐암의 형성에 중요한 역할을 하고 많은 상피세포 종양에서 비정상적으로 활성화됨에 따라 암 치료에 중요한 역할을 하고 있어 EGFR tyrosine kinase inhibitor(TKI)에 관한 많은 연구가 이루어졌다. 위와 같은 약 개발에 있어서 현재 가상 시뮬레이션을 통한 약 후보물질 개발이 진행되고 있다. 특히, Molecular docking 시뮬레이션은 기존의 실험적인 기술(X-ray crystallography, NMR)로는 연구하기가 어려웠던 protein과 ligand간의 상호작용을 예측하여 이에 대한 정보를 제공할 수 있다. 하지만, 우선적으로 Molecular docking 시뮬레이션은 정확한 validation을 기반으로 진행되어야 신뢰할 수 있는 정보를 얻을 수 있다. 따라서 이번 연구에서는 EDISON에서 제공하는 Dock 프로그램과 일반적으로 잘 알려진 Glide, Autodock 프로그램으로 protein data bank(PDB)에서 제공하는 EGFR wild type cocrystal을 redocking하는 방식을 통하여 최상위 rank pose의 RMSD 값을 통한 validation 성능을 비교함으로써 어떤 프로그램이 EGFR과 ligand 간의 결합예측을 하는데 있어서 보다 더 정확한 결과를 낼 수 있는지 알아보고자 하였고 시뮬레이션 결과 Autodock에서 가장 우수한 결과 값을 보여주었다.

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EGFR Antisense Oligonucleotides Encapsulated with Nanoparticles Decrease EGFR, MAPK1 and STAT5 Expression in a Human Colon Cancer Cell Line

  • Najar, Ahmad Gholamhoseinian;Pashaei-Asl, Roghiyeh;Omidi, Yadollah;Farajnia, Safar;Nourazarian, Ali Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.495-498
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    • 2013
  • Epidermal growth factor receptor (EGFR) is over-expressed in several human cancers. This would suggest that inhibition of EGFR is a reasonable approach for cancer treatment. In this study we investigated EGFR blocking and its effects on the mediated signaling such as MAPK and STATb in HT29 cells. For this aim we used FITC-labeled EGFR antisense oligonucleotides encapsulated with PAMAM nanoparticles to inhibit EGFR expression. Cellular uptake of antisense was investigated by fluorescence microscopy and flow cytometry analysis. The effect of EGFR antisense on the expression of EGFR in HT29 cells was examined by real time PCR and Western blots, which showed that antisense encapsulated with PAMAM decreased the level of EGFR mRNA and protein. In addition, real time PCR results confirmed that EGFR inhibition had an effective role in the reduction of EGFR dependent downstream genes. In conclusion, EGFR antisense encapsulated with PAMAM nanoparticles down regulated EGFR and EGFR-mediated genes.

c-Src Antisense Complexed with PAMAM Denderimes Decreases of c-Src Expression and EGFR-Dependent Downstream Genes in the Human HT-29 Colon Cancer Cell Line

  • Nourazarian, Ali Reza;Pashaei-Asl, Roghiyeh;Omidi, Yadollah;Najar, Ahmad Gholamhoseinian
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.2235-2240
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    • 2012
  • c-Src is one member of non-receptor tyrosine kinase protein family that has over expression and activation in many human cancer cells. It has been shown that c-Src is implicated in various downstream signaling pathways associated with EGFR-dependent signaling such as MAPK and STAT5 pathways. Transactivation of EGFR by c-Src is more effective than EGFR ligands. To inhibit the c-Src expression, we used c-Src antisense oligonucleotide complexed with PAMAM Denderimes. The effect of c-Src antisense oligonucleotide on HT29 cell proliferation was determined by MTT assay. Then, the expression of c-Src, EGFR and the genes related to EGFR-depended signaling with P53 was applied by real time PCR. We used western blot analysis to elucidate the effect of antisense on the level of c-Src protein expression. The results showed, c-Src antisense complexed with PAMAM denderimers has an effective role in decrease of c-Src expression and EGFR-dependent downstream genes.