"December 2003" / Includes bibliographical references (leaves 106-128) / xii, 128 leaves : ill., plates ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine and The Hanson Institute, 2004

Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "December 2008." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (M.Med.Sc.)--University of Western Australia, 2006.

No description available.

FAM3B/PANDER, é uma nova proteína tipo citocina pertencente a família FAM3. Foram reveladas algumas similaridades estruturais entre o FAM3B e outras citocinas associadas ao câncer, como IL-6 e FAM3C suportando a hipótese, de que FAM3B também poderia estar envolvido na progressão tumoral. Considerando que o FAM3B é expresso por tumores de mama, este trabalho dedicou-se a elucidar suas possíveis funções em tumores, a partir de um modelo de superexpressão na linhagem celular tumoral da mama, MDA-MB-231. Ensaios celulares e moleculares sugeriram que o FAM3B é capaz de conferir, proteção à morte celular e de aumentar taxa de migração nas células MDA-MB-231 via, principalmente, Bcl-2 e Bcl-xL. Em concordância, os resultados in vivo demonstraram aumento do volume e peso tumoral, com aumento da expressão de Bcl-2 nos tumores dos animais inoculados com as células MDA-MB-231-FAM3B. Estes resultados indicam que esta proteína, exerce funções nas etapas de invasão e metástase em tumores de mama, o que permite considerar o FAM3B, como um possível candidato a marcador tumoral. / FAM3B/PANDER is a new cytokine-like protein, member of the new FAM3 family. Recent data has been shown similarities between FAM3B/PANDER and others citokines involved in tumor progression, like IL-6 and FAM3C/ILEI, supporting the hypothesis that FAM3B is also involved in tumor progression. In Silico data revealed that FAM3B is expressed by breast tumors and using the overexpression of FAM3B in MDA-MB-231 tumor cell line, the aim was evaluated possible roles of FAM3B in breast tumor progression. The results revealed that FAM3B overexpression inhibits cell death and promotes cell migration in MDA-MB-231 cell line, through, at least in parts, Bcl-2 and Bcl-xL pathways. In agreement, in vivo results shown an increase in volume, weight tumors and increase expression of Bcl-2 in mice with cells overexpressing FAM3B.These results suggest important functions of this protein in cell invasiveness and migration, which allows us to consider, FAM3B as a possible future candidate as a molecular biomarker.

A mouse testis cDNA library was screened with an oligonucleotide probe corresponding to a sequence in the 5$ sp prime$ region of mouse N-cadherin cDNA. A composite clone containing three individual cDNAs was isolated. These included a 711 bp cDNA encoding part of mouse testicular N-cadherin, an unidentified 392 bp cDNA, and a 1500 bp cDNA encoding the mouse homologue of a human breast tumor autoantigen. / The cadherins, the influenza strain A hemagglutinins, and the fibroblast growth factor receptors are three different families of integral membrane glycoproteins that harbour the amino acid motif histidine-alanine-valine (HAV) in regions involved in protein-protein interactions. In order to identify other proteins that possess the HAV motif in functionally important regions, the SwissProt database was searched using a consensus sequence derived from the cadherins, influenza strain A hemagglutinins, and fibroblast growth factor receptors. This search identified the $ alpha$ chains of the HLA class I histocompatibility antigens as a fourth family of integral membrane glycoproteins with an HAV-containing region that is involved in a protein-protein interaction. (Abstract shortened by UMI.)

FAM3B/PANDER, é uma nova proteína tipo citocina pertencente a família FAM3. Foram reveladas algumas similaridades estruturais entre o FAM3B e outras citocinas associadas ao câncer, como IL-6 e FAM3C suportando a hipótese, de que FAM3B também poderia estar envolvido na progressão tumoral. Considerando que o FAM3B é expresso por tumores de mama, este trabalho dedicou-se a elucidar suas possíveis funções em tumores, a partir de um modelo de superexpressão na linhagem celular tumoral da mama, MDA-MB-231. Ensaios celulares e moleculares sugeriram que o FAM3B é capaz de conferir, proteção à morte celular e de aumentar taxa de migração nas células MDA-MB-231 via, principalmente, Bcl-2 e Bcl-xL. Em concordância, os resultados in vivo demonstraram aumento do volume e peso tumoral, com aumento da expressão de Bcl-2 nos tumores dos animais inoculados com as células MDA-MB-231-FAM3B. Estes resultados indicam que esta proteína, exerce funções nas etapas de invasão e metástase em tumores de mama, o que permite considerar o FAM3B, como um possível candidato a marcador tumoral. / FAM3B/PANDER is a new cytokine-like protein, member of the new FAM3 family. Recent data has been shown similarities between FAM3B/PANDER and others citokines involved in tumor progression, like IL-6 and FAM3C/ILEI, supporting the hypothesis that FAM3B is also involved in tumor progression. In Silico data revealed that FAM3B is expressed by breast tumors and using the overexpression of FAM3B in MDA-MB-231 tumor cell line, the aim was evaluated possible roles of FAM3B in breast tumor progression. The results revealed that FAM3B overexpression inhibits cell death and promotes cell migration in MDA-MB-231 cell line, through, at least in parts, Bcl-2 and Bcl-xL pathways. In agreement, in vivo results shown an increase in volume, weight tumors and increase expression of Bcl-2 in mice with cells overexpressing FAM3B.These results suggest important functions of this protein in cell invasiveness and migration, which allows us to consider, FAM3B as a possible future candidate as a molecular biomarker.

The aim of this thesis is to establish a simple physical framework that captures and predicts key aspects of the spatial organization of cells in models of breast cancer, while also probing the downstream consequences of particular tumor composition and cell organization within tumors on disease progression. An in vitro model of tumor heterogeneity and a complementary minimal computational model of cell sorting were used to accomplish these goals. We evaluated the tendencies of cells to sort and segregate, the factors driving the sorting process, and the mechanisms of invasion that cells exhibited as a result of different composition and cellular organization. Chapter 1 presents background information on breast cancer progression, the origins and consequences of heterogeneity in tumors and their local microenvironment, existing theoretical and computational approaches to explain cell segregation in tissues, and commonly employed experimental models of cancer invasion. Chapter 2 explores cell sorting of healthy and cancerous breast cells in an in vitro tumor model. This work was motivated by previous observations that mixing genetically distinct breast cancer cells results in cell sorting and the formation of sharp boundaries between cell types, analogous to the segregation of cells during embryonic development. We examined cell segregation among six different breast cell lines and found that more invasive breast cancer cells tended to sort to the outside of mixed cell-type aggregates, such that more aggressive cells were poised to invade the surrounding extracellular matrix. The particular sorting among all binary sets of breast cells studied was found to follow predictions of the differential adhesion hypothesis, which predicts cell sorting to be dependent on a combination of available adhesion proteins and actomyosin contractility. Differential adhesion was found to be a useful lens for not only rationalizing cell sorting tendencies but also directing the assembly of cells. In fact, we showed that through use of a simple contractility inhibiting agent, invasive cell types could be made to sort inside mixed-type aggregates, reducing subsequent invasion. In Chapter 3, we further probed the applicability of differential adhesion frameworks for explaining cell segregation in cancer by employing a Cellular Potts model. Experimentally observed sorting patterns were replicated using a minimal model and varying only two parameters across simulated cell types – one that governs cell morphology and one that governs cell adhesion, thus validating the differential adhesion hypothesis as a useful minimal model to rationalize sorting in this system. Less invasive cell types were found to have more fluid-like character that drives the sorting process and leads to their positioning in the interior of simulated aggregates, surrounded by more invasive cells. We observed evidence of non-equilibrium behavior in certain less adhesive cell types, as well as the capacity for more adhesive cell types to enhance motility and fluidize those that otherwise demonstrate non-equilibrium, slow dynamics. Chapter 4 summarizes these findings and suggests future studies. Throughout this work, we show the value of applying existing views of cell sorting for rationalizing cell segregation and tumor organization in breast cancer. We find that cells sort in a predictable manner that relates to aspects of their adhesive character as captured by differential adhesion, which is shown experimentally to depend on co-regulation of adhesion protein function and actomyosin contractility. These same properties also dictate cell invasive strategy and efficiency, making this a critical area of study to enhance understanding of cancer invasion and metastasis. The drivers of spatial organization of cells in tumors and the consequences of particular organization remain an underexplored topic in breast cancer research. We argue that continued study in this area can yield improved understanding of the impacts of tumor heterogeneity on cancer progression.

No description available.

The application of microanalytical techniques was used to elucidate the enzyme profiles of adenylate cyclase and cAMP-dependent protein kinase within a series of malignant and benign human mammary tumors. The methods allow for determination of enzyme activity in histologically-confirmed neoplastic areas within individual tumors which permits comparisons to be made with particle and cytosolic fractions prepared from mammary tumors. The potential for cAMP formation by adenylate cyclase and mediation of cAMP effects by cAMP-dependent protein kinase were studied to provide information on the levels of enzyme activity and the extent and type(s) of regulation of these enzymes in a cell-free system. Adenylate cyclase (AC) activity levels were higher in benign than malignant tumor tissue on a dry wt basis. A 2 to 3-fold activation by Gpp(NH)p and a 4 to 5-fold stimulation by fluoride was demonstrated. Calmodulin activation of tumor-associated AC was not observed. Membrane-associated AC could be stimulated by PGE₁, prolactin and TSH. Thermal stability studies suggested that AC from malignant tissue was more labile than that from benign tissue. Cyclic AMP-dependent protein kinase associated with human mammary tumors was primarily type II kinase based upon DEAE-Sephacel chromatography and demonstrated a preference for histone VS as a substrate. Cyclic AMP-dependency was supported by enzyme activation by cAMP, by cAMP binding, and inhibition by protein kinase inhibitors and regulatory subunit. The activity ratio was slightly higher in benign than malignant tissue. Histone kinase activity was higher in benign than malignant tumor microsections. Cyclic AMP-binding activity was higher in malignant than benign tumor cytosolic fractions, although cAMP affinity was similar. Catalytic subunit was prepared from tumor histone kinase by cAMP affinity chromatography. Reassociation of tumor catalytic subunit and heterologous regulatory subunit was shown. A cAMP-independent casein kinase was also partially characterized in human mammary tumors. Endogenous phosphorylation in tumor cytosolic fractions was examined and polypeptides identified which showed phosphorylation differences in the presence of cAMP. / Ph. D.