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The objective of the study reported here was to document the distribution of epidermal growth factor receptor (EGFr) and quantitate receptor density in normal as well as ulcerated equine gastric squamous mucosa. Fifteen horses with endoscopically normal stomachs were divided into three equal groups. Group 1 was a normal control. A protocol that alternated 24 hour periods of free-choice hay with 24 hours of feed deprivation was utilized to induce squamous mucosal gastric ulceration in Group 2 (48 hours total off-feed) and Group 3 (96 hours total off-feed). Gastric tissue was collected from 3 stomach locations at post-mortem examination and an avidin-biotin immunoperoxidase technique was developed to stain the formalin-fixed tissue for EGFr. A computerized image analysis system was used to measure EGFr area and mean intensity values at four sites within the epithelium from the basal cell layers to the lumen in the ulcer/erosion margin, erosion bed, and 10-14 mm distant from the lesion. / Master of Science

There is a growing interest in using naturally-occurring compounds as cancer chemopreventive or chemotherapeutic agents. This study investigated the anticancer potential of the graviola fruit extract (GFE) on specific human breast cancer (BC) cells. GFE was found in our preliminary screening to selectively inhibit the growth of certain human BC cells (MDA-MB-468) but did not affect non-transformed breast epithelial MCF-10A cells. GFE treatment was very effective against the growth of MDA-MB-468 BC cells with an IC50 of 4.8 µg/ml. In vitro, effects of GFE treatment on MDA-MB-468 BC cells were further examined for apoptosis and cell proliferation. Apoptosis, determined qualitatively and quantitatively, was enhanced and accompanied by caspase-3 activation. GFE treatment also induced cell cycle arrest at the G1 cell cycle phase and significantly reduced the percentage of MDA-MB-468 cells in S-phase following 24h of exposure. Moreover, the results from analysis of the mRNA expression of epidermal growth factor receptor (EGFR), which plays an important role in regulating cell development and death, by qRT-PCR, suggested that GFE-induced selective growth inhibition of MDA-MB-468 BC cells is associated with a significant inhibition of EGFR gene expression in the cells. In vivo, dietary treatment with GFE significantly inhibited MDA-MB-468 tumor growth implanted in mice by reducing tumor wet weight and significantly reduced EGFR and p-ERK protein expression in tumors. Overall, GFE attenuated cell proliferation, induced apoptosis, modulated cell cycle regulation and downregulated EGFR gene expression both in vitro and in vivo. These discoveries support the further studies to fully elucidate the antitumor potential of GFE and its components as a dietary agent for BC. / Master of Science in Life Sciences

Osteoarthritis (OA) ist eine chronische Erkrankung der Gelenke des menschlichen Körpers, insbesondere des Kniegelenkes. Sie ist durch entzündliche und degenerative Prozesse gekennzeichnet, die Patienten in ihrer Beweglichkeit stark einschränkt. In der komplexen Pathophysiologie kommt es unter anderem zu zellmorphologischen Veränderungen der knorpelbildenden Zellen, den Chondrozyten, und zu destruktiven Veränderungen der Knorpelmatrix. Bisherige therapeutische Ansätze bestehen in meist in einer rein symptomatischen Therapie durch Schmerzmittel sowie der operativen endoprothetischen Versorgung als Ultima Ratio. Eine kurative Therapie ist bisher nicht möglich. Einen Ansatz für eine kurative Therapie könnte eine Subpopulation der Zellen des Knorpelgewebes bieten. Chondrogene Progenitor Zellen (CPCs) stellen als Vorläuferzellen der Chondrozyten, gesteuert durch das prochondrogene Gen SOX9 und das proosteogene Gen RUNX2, einen möglichen regenerativen Ansatz in der Behandlung dar. Eine Rolle in diesem Prozess könnten die Wachstumsfaktoren TGF- β3 und EGF sowie das Matrixmolekül Biglycan darstellen. In dieser Arbeit konnte gezeigt werden, dass diese Wachstumsfaktoren, deren Rezeptoren und das Matrixmolekül Biglycan im osteoarthrischen Knorpel eine Rolle spielen. Insbesondere konnte in vitro gezeigt werden, dass CPCs unter dem Einfluss dieser Moleküle zu einer vermehrten SOX9 und verminderten RUNX2-Expression angeregt werden. Unter der Hypothese, dass sich CPCs auf diese Art zu Chondrozyten differenzieren lassen und so den Knorpel wiederherstellen, könnten diese Moleküle einen möglichen Baustein einer zukünftigen Therapie der OA darstellen.

O presente estudo comparou os efeitos da ativação e inibição do EGFR em duas linhagens de câncer de pulmão, cultivadas em monocamada ou esferoides. Os esferoides foram cultivados sem elementos de matriz extracelular. As células A549 e HK2 apresentaram, respectivamente, 3 e 6 cópias do gene ErbB1 por núcleo, embora a expressão de EGFR seja menor nas células HK2. A ativação de EGFR por EGF ou inibição por AG1478 não promoveu mudanças na proliferação celular. Entretanto, as células cultivadas em monocamada, estimuladas com EGF, exibiram alterações na disposição dos microfilamentos de actina e aumento na velocidade de migração celular. UO126 e LY294002 foram adicionados às culturas para inibir, respectivamente, as vias ERK e Akt. A linhagem A549, cultivada em monocamada, não apresentou envolvimento das vias de sinalização de ERK e Akt na migração celular induzida por EGF, mas foi observado o envolvimento dessas vias nos esferoides. Já a linhagem HK2 apresentou o envolvimento de Akt para promover a migração celular após estímulo com EGF nas duas formas de cultivo. / This study compared the effects of activation and inhibition of EGFR in two cell lines of lung cancer, grown in monolayer or spheroids. Spheroids were cultured without extracellular matrix components. HK2 and A549 cells showed, respectively, 3 and 6 ErbB1 gene copies per nucleus, while EGFR expression is lower in the HK2 cells. The activation by EGF or EGFR inhibition by AG1478 did not cause changes in cell proliferation. However, cells cultured in monolayers stimulated with EGF, showed changes in the arrangement of actin microfilaments and increased the speed of cell migration. UO126 and LY294002 were added to the cultures to inhibit, respectively, the ERK and Akt pathways. A549 cells grown in monolayer did not show involvement of ERK and Akt signaling pathways in the cell migration induced by EGF, but was observed involvement of such pathways in the spheroids. HK2 cells showed involvement of Akt to promote cell migration after EGF stimulation in monolayers and in spheroids.

Yau Mei-sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 96-112). / Abstracts in English and Chinese. / Abstract / Abstract (Chinese Version) / Acknowledgements / List of Abbreviations / Table of Contents / List of Tables / List of Figures / Chapter Chapter 1 --- Introduction / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Hepatocellular Carcinoma / Chapter 2.2 --- Epidermal Growth Factor Receptor / Chapter 2.2.1 --- Activation of Epidermal Growth Factor Receptor / Chapter 2.2.2 --- Epidermal Growth Factor Receptor Signaling Pathways / Chapter 2.2.3 --- Expression Level and Patient Survival / Chapter 2.2.4 --- Epidermal Growth Factor Receptor Activity and Tumor Cell Growth / Chapter 2.2.5 --- Epidermal Growth Factor Receptor Activity and Radiation / Chapter 2.3 --- "Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor, ZD1839" / Chapter 2.3.1 --- Tumor Cell Growth Control Activities of ZD1839 / Chapter 2.3.2 --- Factors Affecting the Tumor Cell Growth Control Activities of ZD1839 / Chapter 2.3.3 --- Radiosensitization Activities of ZD1839 / Chapter 2.3.4 --- Factors Affecting the Radiosensitization Activities of ZD1839 / Chapter 2.4 --- Study Objectives / Chapter Chapter 3 --- Materials and Methods / Chapter 3.1 --- ZD1839 / Chapter 3.2 --- Cell lines and Cell Culture / Chapter 3.3 --- Immunoblot Analysis / Chapter 3.3.1 --- Total Protein Extraction / Chapter 3.3.2 --- Protein Amount Determination / Chapter 3.3.3 --- Protein Separation / Chapter 3.3.4 --- Blotting / Chapter 3.3.5 --- Antibody Labeling / Chapter 3.3.6 --- Detection of Antibody Binding / Chapter 3.4 --- Cytotoxicity Assay / Chapter 3.5 --- Nucleotide sequence analysis / Chapter 3.5.1 --- Total RNA Extraction / Chapter 3.5.2 --- RNA Amount Determination / Chapter 3.5.3 --- Reverse Transcription - Polymerase Chain Reaction (RT-PCR) / Chapter 3.5.3.1 --- Reverse Transcription / Chapter 3.5.3.2 --- High Fidelity Polymerase Chain Reaction / Chapter 3.5.4 --- Purification of PCR Product / Chapter 3.5.5 --- Cycle Sequencing Reaction / Chapter 3.5.6 --- DNA Precipitation and Sequencing / Chapter 3.6 --- Clonogenic Assay / Chapter 3.7 --- Immunohistochemical Analysis / Chapter Chapter 4 --- Results / Chapter 4.1 --- Immunoblot Analysis / Chapter 4.2 --- Cytotoxicity Assay / Chapter 4.2.1 --- Effect of ZD 1839 on cell morphology / Chapter 4.2.2 --- Effect of ZD 1839 on cell growth / Chapter 4.3 --- Nucleotide sequence analysis / Chapter 4.3.1 --- RNA Concentration of HCC cells / Chapter 4.3.2 --- Sequencing of TK domain within EGFR / Chapter 4.3.3 --- Sequencing of TK domain within HER2 / Chapter 4.4 --- Clonogenic assay / Chapter 4.4.1 --- Effects of ZD 1839 pre-treatment on radiation response / Chapter 4.4.2 --- Effects of ZD 1839 continuous treatment on radiation response / Chapter 4.5 --- Immunohistochemical Analysis / Chapter Chapter 5 --- Discussion / Chapter 5.1 --- Important Findings / Chapter 5.2 --- EGFR Expression of HCC Cells / Chapter 5.3 --- Cytotoxicity of ZD1839 on HCC Cell Lines / Chapter 5.4 --- Factors Affecting the Cytotoxicity of ZD1839 / Chapter 5.4.1 --- Effect of EGFR Expression on ZD1839 Cytotoxicity / Chapter 5.4.2 --- Effect of EGFR Mutations on ZD 1839 Cytotoxicity / Chapter 5.4.3 --- Effect of HER2 Expression on ZD1839 Cytotoxicity / Chapter 5.4.4 --- Effect of HER2 Mutations on ZD 1839 Cytotoxicity / Chapter 5.5 --- Radiation Response ofHCC Cell Lines upon ZD1839 Treatment / Chapter 5.6 --- Factors Affecting Radiation Response of ZD1839-treated HCC Cell Lines / Chapter 5.6.1 --- Effect of Growth Arrest on Radiation Response of HCC Cell Lines / Chapter 5.6.2 --- Other Factors Affecting Radiation Response of HCC Cell Lines / Chapter Chapter 6 --- Conclusion / References

Poon, Fan Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 109-124). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Table of Content --- p.vi / List of Figures --- p.xi / List of Tables --- p.xiii / List of Abbreviations --- p.xiv / List of papers published during the study --- p.xvi / Chapter Chapter 1 --- Introduction and Aim of Study --- p.1 / Chapter 1.1 --- General Introduction --- p.1 / Chapter 1.2 --- Project objective and potential significances --- p.6 / Chapter Chapter 2 --- Literature Reviews --- p.8 / Chapter 2.1 --- Cancer genetics --- p.8 / Chapter 2.1.1 --- Oncogenes and TSGs --- p.8 / Chapter 2.1.2 --- Kundsońةs two-hit event of cancer gene --- p.9 / Chapter 2.2 --- Cancer Epigenetics --- p.9 / Chapter 2.2.1 --- Types of Epigenetic regulation --- p.10 / Chapter 2.2.2 --- DNA methylation in TSGs --- p.10 / Chapter 2.2.2.1 --- Promoter CpG island in DNA methylation --- p.10 / Chapter 2.2.2.2 --- Protection system in DNA methylation --- p.11 / Chapter 2.2.2.3 --- Transcriptional silencing by DNA methylation --- p.11 / Chapter 2.2.2.4 --- DNA methylation of TSG silencing in cancers --- p.13 / Chapter 2.2.3 --- Hypomethylation of the cancer genome --- p.14 / Chapter 2.2.4 --- Clinical relevance of cancer epigenetic --- p.14 / Chapter 2.3 --- EGFR/STAT/SOCS pathway --- p.15 / Chapter 2.3.1 --- General Introduction of the EGFR pathway --- p.15 / Chapter 2.3.2 --- EGFR survival signaling pathways --- p.16 / Chapter 2.3.3 --- EGFR/STAT/SOCS signaling --- p.17 / Chapter 2.3.4 --- EGFR/STAT/SOCS signaling and cancers --- p.18 / Chapter 2.3.4.1 --- EGF and cancers --- p.18 / Chapter 2.3.4.2 --- EGFR/STAT/SOCS pathway and cancers --- p.18 / Chapter 2.3.4.3 --- EGF survival signaling as a target for cancer therapy --- p.19 / Chapter 2.4 --- TSGs in the EGFR/STAT/SOCS pathway --- p.20 / Chapter 2.4.1 --- Suppressors of cytokine signaling (SOCS) family --- p.20 / Chapter 2.4.2 --- Signal transducers and activators of transcription (STATs) family --- p.22 / Chapter 2.4.3 --- Sprouty (SPRY) family --- p.23 / Chapter 2.4.4 --- Protein Inhibitor of Activated STAT (PIASs) family --- p.25 / Chapter 2.4.5 --- Ras and Rab Interactor (RIN) family --- p.26 / Chapter 2.4.6 --- Ras-association domain family (RASSF) --- p.26 / Chapter 2.4.7 --- Glycine N-methyltransferase (GNMT) --- p.28 / Chapter 2.5 --- Nasopharyngeal carcinoma (NPC) --- p.30 / Chapter 2.5.1 --- Epidemiology of NPC --- p.30 / Chapter 2.5.2 --- Histopathology of NPC --- p.30 / Chapter 2.5.3 --- Genetic and epigenetic alteration in NPC --- p.31 / Chapter 2.5.4 --- EGFR signaling in NPC --- p.32 / Chapter 2.6 --- Esophageal squamous cell carcinoma (ESCC) --- p.33 / Chapter 2.6.1 --- Epidemiology of ESCC --- p.34 / Chapter 2.6.2 --- Histopathology of ESCC --- p.34 / Chapter 2.6.3 --- Genetic and epigenetic alteration in ESCC --- p.35 / Chapter 2.6.4 --- EGFR signaling in ESCC --- p.36 / Chapter Chapter 3 --- Materials and Methods --- p.38 / Chapter 3.1 --- General Materials --- p.38 / Chapter 3.1.1 --- "Cell lines, tumor and normal tissue samples" --- p.38 / Chapter 3.1.2 --- Maintenance of cell lines --- p.38 / Chapter 3.1.3 --- Drugs treatment of cell lines --- p.39 / Chapter 3.1.4 --- Total RNA extraction --- p.39 / Chapter 3.1.5 --- Genomic DNA extraction --- p.40 / Chapter 3.2 --- General techniques --- p.40 / Chapter 3.2.1 --- Agarose gel electrophoresis of DNA --- p.40 / Chapter 3.2.2 --- TA cloning and blunt end cloning of PCR product --- p.40 / Chapter 3.2.3 --- Transformation of cloning products to E. coli competent cells --- p.41 / Chapter 3.2.4 --- Preparation of plasmid DNA --- p.41 / Chapter 3.2.4.1 --- Mini-prep plasmid DNA extraction --- p.41 / Chapter 3.2.4.2 --- Midi-prep of plasmid DNA --- p.42 / Chapter 3.2.5 --- Measurement of DNA or RNA concentrations --- p.42 / Chapter 3.2.6 --- DNA sequencing of plasmid DNA and PCR products --- p.42 / Chapter 3.3 --- Preparation of reagents and medium --- p.43 / Chapter 3.4 --- Semi-quatitative Reverse-Transcription (RT) PCR expression analysis --- p.44 / Chapter 3.4.1 --- Reverse transcriptin reaction --- p.44 / Chapter 3.4.2 --- Semi-quantitative RT-PCR --- p.44 / Chapter 3.4.2.1 --- Primers design --- p.44 / Chapter 3.4.2.2 --- PCR reaction --- p.46 / Chapter 3.5 --- Methylation analysis of candidate genes --- p.47 / Chapter 3.5.1 --- Bisulfite treatment of genomic DNA --- p.47 / Chapter 3.5.2 --- Methylation-specific PCR (MSP) --- p.48 / Chapter 3.5.2.1 --- Bioinformatics prediction of CpG island --- p.48 / Chapter 3.5.2.2 --- Primers design --- p.48 / Chapter 3.5.2.3 --- PCR reaction --- p.49 / Chapter 3.5.3 --- Bisulfite Genomic Sequencing (BGS) --- p.50 / Chapter 3.6 --- Construction of expression vectors of candidate genes --- p.51 / Chapter 3.6.1 --- Sub-cloning of expression vector of candidate genes --- p.51 / Chapter 3.6.1.1 --- Mouse Socsl expression vector --- p.51 / Chapter 3.6.1.2 --- SPRY1 expression vector --- p.51 / Chapter 3.6.1.3 --- GNMT expression vector --- p.52 / Chapter 3.6.2 --- Restriction digestion of cloning vectors and expression --- p.52 / Chapter 3.6.3 --- Ligation of cloning fragments --- p.53 / Chapter 3.6.4 --- Colony formation assay on monolayer culture --- p.53 / Chapter 3.6.5 --- Statistical analysis --- p.54 / Chapter Chapter 4 --- Screening of candidate TSGs in EGFR pathway --- p.55 / Chapter 5.3.3 --- Restoration of GNMT expression by pharmacological demethylation --- p.89 / Chapter 5.3.4 --- Confirmation of the methylation status of GNMT promoter by BGS --- p.90 / Chapter 5.3.5 --- Methylation status of GNMT in ESCC and NPC primary tumors --- p.90 / Chapter 5.3.6 --- GNMT inhibited the growth of tumor cells in-vitro --- p.90 / Chapter 5.3.7 --- Discussion --- p.95 / Chapter Chapter 6 --- General Discussion --- p.100 / Chapter Chapter 7 --- Summary --- p.105 / Chapter Chapter 8 --- Future Study --- p.107 / Reference --- p.109

BACKGROUND: Prostate cancer is by far the most common cancer among Swedish men. Some patients have an aggressive lethal disease, but the majority of affected men have long expected survival. Unfortunately, the diagnostic tools available are insufficient in predicting disease aggressiveness. Novel prognostic markers are therefore urgently needed. Furthermore, metastatic prostate cancer is generally treated with castration, but the long-term effects are insufficient. Additional studies are therefore needed to explore how the effects of this therapy can be enhanced. Prostate growth and regression is beside testosterone controlled by locally produced regulators. Vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) are two of the major regulators in the normal prostate and in prostate tumours. MATERIALS AND METHODS: VEGF and EGFR were explored in the prostate, by treating rats with either anti-VEGF or anti-EGFR treatment during castration and testosterone-stimulated prostate growth. Rats with implanted androgen-independent prostate tumours were treated with an inhibitor of both VEGF receptor-2 (VEGFR-2) and EGFR. Stereological techniques, immunohistochemistry, western blotting and quantitative real-time PCR were used to evaluate these experiments. Furthermore, prostate tissue from untreated prostate cancer patients was used to retrospectively explore the expression of phosphorylated-EGFR (pEGFR) in relation to outcome. RESULTS: Anti-VEGF treatment during testosterone-stimulated prostate growth, inhibited vascular and prostate growth. Anti-EGFR treatment during castration and testosterone-stimulated prostate growth resulted in enhanced castration effects and inhibited prostate growth. Anti-vascular treatment of androgen-independent prostate cancer with an inhibitor of VEGFR-2 and EGFR, that targets the normal and tumour vasculature, enhanced the effects of castration. Low immunoreactivity for pEGFR in prostate epithelial cells, both in the tumour and also in the surrounding non-malignant tissue, was associated with good prognosis. CONCLUSIONS: Anti-vascular treatment, with an inhibitor of VEGFR-2 and EGFR, in combination with castration could be an effective way to treat androgen-insensitive prostate tumours. VEGF and EGFR signalling are necessary components in testosterone-stimulated prostate growth. Phosphorylation of EGFR could be a useful prognostic marker for prostate cancer patients. Tumours may affect the surrounding non-malignant tissue and pEGFR immunoreactivity in the morphologically normal prostate tissue can be used to retrieve prognostic information.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 4 uppsatser. Även tryckt utgåva.

Novel biocompatible nanoprobes for optical imaging of Epidermal Growth Factor receptor (EGFR) were created. 5 and 18 nm gold nanoparticles (AuNPs) and 5 and 45 nm diameter silver nanoparticles (AgNPs) were conjugated to EGF protein via ?-lipoic acid. AgNPs were not previously attached to EGF. TOF-MS confirms EGF-linker formation. ELISA verifies the linked-EGF activity alone and with EGF-NPs. Core-shell silver-gold nanoparticles (AgAuNPs) gave similar results. TEM staining with uranyl acetate exhibits a bright ring, smaller than EGF, around nanoparticles. Dark field microscopy shows localized, intense cytoplasmic scattering, possibly lipid droplets, in cancer cells incubated with or without nanoprobes. Following injection, mice organs were harvested for EGF-NP immune response determination. Sterilization likely inactivated EGF before ICP-MS. Intense surface enhanced Raman scattering (SERS, 632.8 nm) follows MgSO4 induced EGF-AgNPs aggregation. Pelleted EGF-AgNP tagged cancer cells lack SERS indicative intensity contrast. AgAuNPs could provide increased stability, brighter SERS, and reduced silver biocompatibility concerns.