Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 103-121).

Thesis (Ph. D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 157-202).

Thesis (Ph. D.)--University of Virginia, 1999. / Spine title: SNON modulates gene activity. Includes bibliographical references (p. 208-232). Also available online through Digital Dissertations.

Thesis (doctoral)--University of Göteborg, 1989. / Extra t.p. with thesis statement inserted. Includes bibliographical references.

Orientador: Solange Bento Farah / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-20T13:10:27Z (GMT). No. of bitstreams: 1 Cerutti_JaneteMaria_D.pdf: 5121566 bytes, checksum: bf43be08156195f0d58ec199165339ea (MD5) Previous issue date: 1995 / Doutorado / Genetica / Doutor em Ciências Biológicas

Orientador: Carmen Silvia Bertuzzo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T22:32:33Z (GMT). No. of bitstreams: 1 Santiago_MariliaBueno_M.pdf: 1534598 bytes, checksum: 1b88c82597c2b286ee6cd5c4c13cec4b (MD5) Previous issue date: 2011 / Resumo: O câncer é um dos problemas mais comuns da medicina atual, com cerca de 481.100 novos casos por ano, atingindo mais de um terço da população mundial. O câncer de cabeça e pescoço em sua maioria é representado por neoplasias epiteliais do tipo carcinoma de células escamosas (CEC) que acometem as vias superiores aéro-digestivas. A grande maioria dos casos é representada por tumores esporádicos. Estudos têm associado o CEC a alguns polimorfismos como o Kras-LCS6, que reduz significativamente o tempo de vida em pacientes com tumores de cabeça e pescoço e sugere que esta variante pode alterar o fenótipo ou a resposta terapêutica da doença e o polimorfismo associado ao transporte sódio dependente de vitamina C, SLC23A2-05, que modifica o risco de câncer de cabeça e pescoço em indivíduos portadores do HPV16 Humano, HPV positivos têm risco aumentado, enquanto nos negativos este risco se reduz. O objetivo do presente estudo foi avaliar a prevalência dos polimorfismos Kras-LCS6 e SLC23A2-05 em uma amostra de pacientes com carcinoma de células escamosas de cabeça e pescoço, verificando a importância desses polimorfismos no acometimento e na gravidade da doença, através de um estudo de associação. Foi utilizada a técnica de PCR associada a digestão enzimática. Foram avaliados 165 casos e 230 controles para cada polimorfismo. No polimorfismo Kras-LCS6 a freqüência gênica dos alelos T e G encontradas foram de 0,91 e 0,09 na amostra do grupo caso e 0,90 e 0,10 na amostra controle. Para o polimorfismo SLC23A2-05 a freqüência gênica dos alelos C e G foram de 0,47 e 0,53, respectivamente, tanto no grupo de caso quanto no grupo controle. Da análise do teste de regressão logística, nenhuma associação foi encontrada entre os polimorfismos analisados e o CEC, bem como com o estadiamento da doença / Abstract: Cancer is one of the most common problems in medicine today, with approximately 481,100 new cases per year, reaching more than a third of the world population. Head and neck cancer is mostly represented by type of skin cancer squamous cell carcinoma affecting the upper aero-digestive pathways. The majority of cases is represented by sporadic tumors Studies have associated some gene polymorphisms with head and neck squamous cell carcinoma (HNSCC) as the Kras-LCS6, which reduces significantly the survival in patients with head and neck tumors and suggests that this variant may alter the phenotype of the disease or therapeutic response and polymorphisms associated with sodium-dependent vitamin C, SLC23A2-05, which modifies the risk of head and neck cancer in individuals with the Human HPV16, positive HPV have an increased risk, while in the negative this risk is reduced. The aim of this study was to evaluate the prevalence of polymorphisms Kras-LCS6 and SLC23A2-05 in a sample of patients with head and neck squamous cell carcinomas, verifying the importance of these polymorphisms in the onset and severity of the disease, through a study of association. We used the PCR method combined with PCR-RFLP. We evaluated 165 cases and 230 controls for each gene polymorphism. In Kras-LCS6 Polymorphism found the gene frequency of 0.91 and 0.09 T and G alleles in the sample of patients and 0.90 and 0.10 in the control sample. For the SLC23A2-05 polymorphism gene frequency of the C and G alleles were 0.47 and 0.53, respectively, both in the patient group and control group. In logistic regression test analysis, we don't found any association between two polymorphisms studied and HNSCC, as well as with the disease staging / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

The epidermal growth factor receptor (EGFR) gene was examined as a proto-oncogene. Initially, the cellular homolog of the retroviral oncogene erb-B was shown to be localized to the same region of human chromosome 7 as the EGFR gene, giving support to the idea that these genes are closely related. To determine how some cells can over-express the EGFR gene, somatic cell hybrids constructed between a human EGFR-overproducing cell line and a mouse EGFR-deficient cell line were examined. EGFR gene amplification was observed in one of these hybrids along with EGFR gene rearrangement, which is thought to generate an abnormal mRNA. When examining tumor tissue, the EGF receptor (EGFR) was found to be elevated relative to normal adjacent tissue in 9 out of 15 primary human squamous cell carcinomas. Only 2 of these 9 tumors had EGFR gene amplification, suggesting alternative mechanisms potentially involved in increasing EGFR levels. Because placental tissue expresses high levels of EGFR, it was thought that some tissues may normally possess high EGFR levels and that some cancerous tissues inappropriately mimic the mechanisms active in the placenta. From the examination of several tissue samples, EGFR mRNA levels and EGFR protein half-life were also postulated as contributing factors regulating the EGFR levels. The EGFR gene was implicated as a proto-oncogene by evidence which suggests that either a qualitative or a quantitative change in the receptor may be involved in tumorigenesis. Finally, to begin to better understand what role EGFR hyperproduction plays in tumorigenesis, a DNA vector was constructed which produces antisense-RNA for inhibiting EGFR expression.

No description available.

published_or_final_version / Surgery / Doctoral / Doctor of Philosophy

The Best PhD Thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,2009-2010 / published_or_final_version / Clinical Oncology / Doctoral / Doctor of Philosophy