Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2007 Apr 14

Radiotherapy is second only to surgery in the curative management of patients with cancer, and yet the molecular mechanisms that determine the sensitivity of tumours to radiation remain largely unclear. A high-throughput radiosensitivity screening method based on clonogenicity was developed and a siRNA library against kinase targets was screened. The gold standard colony formation endpoint was chosen for determining reproductive cell death after radiation treatment, since effects on proliferation often do not reflect survival. Thiamine pyrophosphokinase-1 (TPK1), a key component of Vitamin B1/thiamine metabolism, was identified as a target for radiosensitisation. TPK1 knockdown caused significant radiosensitisation in cancer but not normal tissue cell lines. Other means of blocking this pathway such as knockdown of thiamine transporter-1 (THTR1) or treatment with the thiamine analogue pyrithiamine hydrobromide (PyrH) caused significant tumour specific radiosensitisation. There was persistent DNA damage in cells irradiated after TPK1 and THTR1 knockdown or PyrH treatment. Thus this screen allowed the identification of thiamine metabolism as a novel radiosensitisation target that affects DNA repair. Short-term modulation of thiamine metabolism could be a clinically exploitable strategy to achieve tumour specific radiosensitisation. Three additional genes, signal recognition particle-72 kDa (SRP72), glycogen synthase 3-beta (GSK3β) and MAP/Microtubule Affinity-Regulating Kinase 2 (MARK2) were also investigated. Knockdown of these genes radiosensitised both tumour and normal tissue cell lines and expression of two of them, GSK3β and SRP72 were found to be associated with poor recurrence-free survival in early breast cancer patients.

A compreensão dos mecanismos que regulam o endométrio e suas implicações clínicas podem contribuir para melhorar as taxas de implantação do embrião humano. Apesar de muitas proteínas e moléculas influenciarem a receptividade endometrial, sua contribuição coordenada para o processo de implantação do embrião ainda é pouco compreendida. Dentre a complexa rede que guia este processo em direção à preparação de um endométrio receptivo se encontram as citocinas, das quais a interleucina-11 (IL-11) e o fator inibidor de leucemia (LIF) desempenham papel essencial. Estudos demonstram que a interrupção das vias de sinalização celular dessas citocinas prejudica ou mesmo impede a implantação, implicando diretamente na fertilidade feminina. Além disso, a hiperinsulinemia afeta negativamente a fertilidade da mulher. Dentro desse contexto, a metformina, fármaco antidiabético, pode exercer efeitos positivos sobre a expressão da IL-11 e LIF, revertendo o possível prejuízo do excesso de insulina sobre a secreção dessas citocinas. Para avaliar esse efeito, utilizou-se um modelo de cultura primária de células estromais de endométrio humano expostas aos hormônios sexuais femininos estrogênio e progesterona, divididas em grupos: controle, metformina, insulina, e associação insulina e metformina. Utilizando RT-qPCR e ensaio imunoenzimático de ELISA, foram avaliadas a expressão gênica e proteica, respectivamente, das duas citocinas. Não foram observadas diferenças entre os grupos. O ensaio de MTT para avaliar a proliferação celular permitiu a verificação da ação antiproliferativa da metformina sobre o grupo hiperinsulinêmico. Embora as hipóteses formuladas nesse estudo encontrem forte sustentação na literatura, no modelo proposto não foi possível encontrar diferenças na expressão da IL-11 e LIF. Dada a complexa regulação de todos os fatores considerados nessa pesquisa e suas múltiplas inter-relações, mais estudos são necessários para esclarecer os mecanismos que orquestram essa complexa rede. / The understanding of the endometrium regulation and its clinical implications can help to improve implantation rates of the human embryo. Although many proteins and molecules influence the endometrial receptivity, their coordinated contribution to embryo implantation process is still poorly understood. Among the complex pathways involved in this process toward the preparation to a receptive endometrium are the cytokines, including interleukin -11 (IL- 11) and leukemia inhibitory factor (LIF) that play an essential role. It has been shown that disruption of cellular signaling pathways of these cytokines impairs or even prevents implantation, direct implications on fertility. Moreover, the hyperinsulinemia can negatively affected women's fertility. Within this context, metformin, an antidiabetic drug, may exert positive effects on the expression of IL-11 and LIF, reversing the possible effects insulin excess. To evaluate this effect, a model of primary culture of human endometrial stromal cells exposed to female sex hormones estrogen and progesterone was used. Cells were divided in groups: control, metformin, insulin, association insulin and metformin. From qRT-PCR and ELISA immunoenzymatic assay gene expression and protein, respectively, of the two cytokines were evaluated. No differences were observed between groups. Additionally, the assay to evaluate cell proliferation MTT found the important antiproliferative action of metformin on hyperinsulinemic group. In the proposed model could not find differences in the expression of IL-11 and LIF. Given the complex regulation of all factors considered in this study and their multiple interrelationships, more studies are required to unravel the mechanisms that orchestrate this complex network.

A compreensão dos mecanismos que regulam o endométrio e suas implicações clínicas podem contribuir para melhorar as taxas de implantação do embrião humano. Apesar de muitas proteínas e moléculas influenciarem a receptividade endometrial, sua contribuição coordenada para o processo de implantação do embrião ainda é pouco compreendida. Dentre a complexa rede que guia este processo em direção à preparação de um endométrio receptivo se encontram as citocinas, das quais a interleucina-11 (IL-11) e o fator inibidor de leucemia (LIF) desempenham papel essencial. Estudos demonstram que a interrupção das vias de sinalização celular dessas citocinas prejudica ou mesmo impede a implantação, implicando diretamente na fertilidade feminina. Além disso, a hiperinsulinemia afeta negativamente a fertilidade da mulher. Dentro desse contexto, a metformina, fármaco antidiabético, pode exercer efeitos positivos sobre a expressão da IL-11 e LIF, revertendo o possível prejuízo do excesso de insulina sobre a secreção dessas citocinas. Para avaliar esse efeito, utilizou-se um modelo de cultura primária de células estromais de endométrio humano expostas aos hormônios sexuais femininos estrogênio e progesterona, divididas em grupos: controle, metformina, insulina, e associação insulina e metformina. Utilizando RT-qPCR e ensaio imunoenzimático de ELISA, foram avaliadas a expressão gênica e proteica, respectivamente, das duas citocinas. Não foram observadas diferenças entre os grupos. O ensaio de MTT para avaliar a proliferação celular permitiu a verificação da ação antiproliferativa da metformina sobre o grupo hiperinsulinêmico. Embora as hipóteses formuladas nesse estudo encontrem forte sustentação na literatura, no modelo proposto não foi possível encontrar diferenças na expressão da IL-11 e LIF. Dada a complexa regulação de todos os fatores considerados nessa pesquisa e suas múltiplas inter-relações, mais estudos são necessários para esclarecer os mecanismos que orquestram essa complexa rede. / The understanding of the endometrium regulation and its clinical implications can help to improve implantation rates of the human embryo. Although many proteins and molecules influence the endometrial receptivity, their coordinated contribution to embryo implantation process is still poorly understood. Among the complex pathways involved in this process toward the preparation to a receptive endometrium are the cytokines, including interleukin -11 (IL- 11) and leukemia inhibitory factor (LIF) that play an essential role. It has been shown that disruption of cellular signaling pathways of these cytokines impairs or even prevents implantation, direct implications on fertility. Moreover, the hyperinsulinemia can negatively affected women's fertility. Within this context, metformin, an antidiabetic drug, may exert positive effects on the expression of IL-11 and LIF, reversing the possible effects insulin excess. To evaluate this effect, a model of primary culture of human endometrial stromal cells exposed to female sex hormones estrogen and progesterone was used. Cells were divided in groups: control, metformin, insulin, association insulin and metformin. From qRT-PCR and ELISA immunoenzymatic assay gene expression and protein, respectively, of the two cytokines were evaluated. No differences were observed between groups. Additionally, the assay to evaluate cell proliferation MTT found the important antiproliferative action of metformin on hyperinsulinemic group. In the proposed model could not find differences in the expression of IL-11 and LIF. Given the complex regulation of all factors considered in this study and their multiple interrelationships, more studies are required to unravel the mechanisms that orchestrate this complex network.

The fast paced evolution of technology has changed the way people interact with service providers in a significant way; the introduction of new service delivery channels has mainly been based on technological advances rather than on customer needs. During the last 20 years the banks have extended their service offerings from just having the branch offices to the multichannel service delivery systems of today, including; phones, computers and smartphone apps. Previous research has concluded that there were many barriers for mobile banking to become a widespread service delivery channel for banks, such as technical limitations, trust issues and social obstacles. In order to understand the role of the smartphone in this multichannel ecology, a qualitative interview study was undertaken focusing on the customers’ perception of the bank. The results show that the choice of channel is dependent on personal characteristics, perceived risk, context and how the task itself is perceived. The results show that the current role of the smartphone is complementary to the other channels, providing the customer with basic banking services wherever they are; it supports the customer in the activity of managing ones private economy and providing the informant with the feeling of control. The results also include insights into the life of three customers and their interaction with their bank over the course of one month in the form of customer journey maps.

No / Radiotherapy is a major treatment modality used to treat muscle-invasive bladder cancer, with patient outcomes similar to surgery. However, radioresistance is a significant factor in treatment failure. Cell-free extracts of muscle-invasive bladder tumors are defective in nonhomologous end-joining (NHEJ), and this phenotype may be used clinically by combining radiotherapy with a radiosensitizing drug that targets homologous recombination, thereby sparing normal tissues with intact NHEJ. The response of the homologous recombination protein RAD51 to radiation is inhibited by the small-molecule tyrosine kinase inhibitor imatinib. Stable RT112 bladder cancer Ku knockdown (Ku80KD) cells were generated using short hairpin RNA technology to mimic the invasive tumor phenotype and also RAD51 knockdown (RAD51KD) cells to show imatinib's pathway selectivity. Ku80KD, RAD51KD, nonsilencing vector control, and parental RT112 cells were treated with radiation in combination with either imatinib or lapatinib, which inhibits NHEJ and cell survival assessed by clonogenic assay. Drug doses were chosen at approximately IC40 and IC10 (nontoxic) levels. Imatinib radiosensitized Ku80KD cells to a greater extent than RAD51KD or RT112 cells. In contrast, lapatinib radiosensitized RAD51KD and RT112 cells but not Ku80KD cells. Taken together, our findings suggest a new application for imatinib in concurrent use with radiotherapy to treat muscle-invasive bladder cancer. Cancer Res; 73(5); 1611-20. (c)2012 AACR.