La polarité planaire ou PCP est un processus dans lequel les cellules et des structures apicales sedéveloppent et s’orientent dans le plan de l’épithélium. Cette polarité est régulée par un ensemble deprotéines incluant Vangl2. Un mutant murin de Vangl2 nommé looptail présente une forme sévèred’absence de fermeture du tube neural. Des pertes de fonctions de Vangl2 sont également retrouvées chezdes enfants atteints de défaut de fermeture du tube neural. Vangl2 possède un motif d’interaction pour desdomaines PDZ et s’organise en protéine à quatre domaines transmembranaires. Malgré de nombreusesdonnées génétiques disponibles concernant la perte de fonction de Vangl2, beaucoup reste à faire pourélucider les mécanismes moléculaires impliqués. Le locus du gène vangl2 humain est localisé dans unerégion fréquemment réarrangée dans différents cancers incluant les cancers du sein. Nous nous sommesintéressés à l’expression de Vangl2 dans les cancers du sein. Nous montrons que Vangl2 est surexprimédans des cancers du sein de sous-type basal (cancers du sein agressifs et de mauvais pronostic) danslesquels le locus génétique de Vangl2 est significativement amplifié et où le niveau d’expression del’ARNm et de la protéine est également élevé. De plus, par des études in vitro et in vivo, nous démontronsle rôle de Vangl2 dans la croissance tumorale et dans les processus de migration cellulaire. Ces effets sontdépendants de son motif d’interaction aux domaines PDZ et sont dépendants de Scrib, une autre protéinede la PCP, étudiée dans l’équipe et impliquée dans les processus de migration cellulaire. Par desexpériences de gain et de perte de fonction dans des cellules de cancers du sein, nous démontrons quel’expression de Vangl2 régule la signalisation JNK via l’activité des GTPases Rac1 et Cdc42 importantespour les processus de réorganisation du cytosquelette d’actine. L’ensemble de nos données indique un rôlerégulateur de Vangl2 dans les processus de tumorigenèse l’impliquant dans la croissance tumorale, laprolifération et migration cellulaires. / Planar cell polarity (PCP) is a process by which cells and apical structures grow in a uniformorientation within the plane of the epithelium. This type of polarity is regulated by a set of “core” proteinsincluding Vangl2. A vangl2 mutant, known as looptail exhibits a severe form of neural tube defect.Mutations of vangl2 associated to neural tube defects were also described in human. Vangl2 possesses aPDZ binding motif and is potentially organized in a four transmembrane domain structure. While geneticdata has very well described the importance of Vangl2 in embryonic development, its molecular functionsare still unknown. The human vangl2 gene is localized in a region with frequent rearrangements involvedin multiple cancers, including breast cancer. We decided to explore the expression of Vangl2 in breastcancer and defined Vangl2 as a PCP “core” protein associated with a signature of poor prognosis basaltypebreast cancer. The Vangl2 genetic locus is amplified in breast cancers, and this amplificationcorrelates with high mRNA and protein levels. Moreover, in in vitro and in vivo studies, we demonstratethe role of Vangl2 in tumor growth and cell migration. These functions are dependent on its PDZ bindingmotif and implicates Scrib, a PCP protein containing PDZ domains and involved in cell migration. Finally,using gain-of-function and loss-of-function approaches in breast cancer cell lines, we demonstrate thatVangl2 modulates the JNK pathway activation via the Rac1 and Cdc42 GTPases which are important forcytoskeleton reorganization. Together, our data reveal that Vangl2 has a role in tumor growth, cellproliferation and cell migration.

Background: Estrogen receptor (ER)- and progesterone receptor (PR)-negative (ER-PR-) breast cancer is associated with higher grade and poorer prognosis compared with other breast cancer subtypes. High parity, coupled with lack of breastfeeding, has been associated with an increased risk of ER-PR- cancer. The mechanism of this etiology is unclear, and may be obfuscated by ER and PR correlation with each other as well as other prognostic tumor characteristics. Methods: Using population-based and clinic-based ascertained cases and controls from the Breast Cancer Family Registry, I examined reproductive risk factors, including parity, breastfeeding, and oral contraceptive (OC) use, in relation to ER and PR status, using polytomous logistic regression (for the population-based data) and the method of generalized estimating equations (GEE) (for the clinic-based data) as well as the pseudo-conditional likelihood approach, which accounts for correlated outcome variables. Results: High parity (≥ 3 live births) combined with lack of breastfeeding, was positively associated with ER-PR- tumors (odds ratio [OR]=1.57, 95% confidence interval [CI] 1.10-2.24, population-based cases vs. controls) relative to nulliparity. There was no association with ER-PR- tumors and parity in women who breastfed (OR=0.93, 95%CI 0.71-1.22) relative to nulliparous women. Associations with ER-PR- cancer were higher across all races/ethnicities among women who did not breastfeed compared with women who did. Population-based and clinic-based data were generally in agreement (OR=2.07, 95% CI 1.09-3.91, clinic-based cases vs. controls, relative to nulliparity). When adjusted for the correlation of PR-status and grade, to ER-status, the association between high parity +lack of breastfeeding and ER- status, was maintained. OC use before year 1975 was associated with an increased risk of ER-PR- tumors (OR=1.32, 95% CI 1.04-1.67, population-based data, cases vs. controls) relative to never use of OCs. For women who began OC use in 1975 or later there was no increased risk. Analysis of OC use in clinic-based data agreed with the findings of the population-based data. Conclusions: My findings support that there are modifiable factors for ER-PR- breast cancer, and that breastfeeding in particular may mitigate the increased risk of ER-PR-cancers seen from multiparity. The mechanism of both risk and risk mitigation may operate primarily through the estrogen, rather than progesterone, pathway.

Includes bibliographies. / [xvii], 173, [38] leaves, [18] leaves of plates : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis presents the development of an assay for reverse transcription-polymerase chain reaction (RT-PCR) to be applied to the immunomagnetic isolation of carcinoma cells, as a possible means of detecting small numbers of breast cancer cells in a haemopoietic environment. The messenger RNA expression of two different genes, CD44 and the cytokeratin K19, is assessed for suitability as tumour markers for the Immunobead RT-PCR method, and clinical results using K19 are presented. / Thesis (M.D.)--University of Adelaide, Dept. of Medicine, 1977?

Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Made available in DSpace on 2014-08-20T14:37:50Z (GMT). No. of bitstreams: 1 tese_isabel cristina_pereira.pdf: 914766 bytes, checksum: c37475e752545b7fee514cfc04ce4f2e (MD5) Previous issue date: 2012-06-27 / The longevity of dogs has increased the number of neoplasm cases, and the breast neoplasm is one of the most frequent diagnosed in this species. The female dogs are important as a study population as they present similarities between the breast neoplasms developed in humans and canines, thus allowing the use of the compared pathology in an attempt to have a better understanding of the disease. Changes in calcium and magnesium levels may be related to the presence and occurrence of breast neoplasms, but there is no defined standardization of these changes. The study aimed to analyze epidemiological data in canine patients with breast neoplasms, determine levels of serum calcium and magnesium in dogs with breast neoplasms before and after excision, and associate variation of calcium and magnesium blood levels with the neoplasms malignity. The study had a sample of 53 females 53 female dogs with tumors in the mammary gland, from which we obtained data of descriptive characteristics of the sample, regarding the review of the animal, exposure to risk factors and tumor development, associated with the morphological characteristics and anatomical location. Excision of tumor masses was performed for histopathological analysis evaluating the surgical margin and classifying the patients according to the biological behavior and malignancy degree: high malignancy (HM), intermediate malignancy (IM), low malignancy (LM) and benign (B). In further study, there was a loss of 17 dogs in the study for the analysis of mineral levels the period of 180 days and analyzed 36 dogs with mammary neoplasms and 28 healthy dogs without breast tumors were studied as controls. Dogs were evaluated on day zero (before surgery) in regard to assessments of tumor mass, and on that date, surgery was carried out in order to send the tumoral part for anatomopathologic evaluation taking into account the classification in biological behavior. Serum calcium and magnesium dosage (absorbance spectrophotometry) was performed prior to the excision of tumors (on day zero) and at 60 and 180 days after surgery, and at the same time interval the serum levels of minerals in the control group were evaluated. Of the 53 dogs studied, 24 showed high malignant tumors, 12 intermediate malignant tumors, 13 low malignancy tumors and four benign tumors. The elderly patients were the most frequent ones in the malignancy group. There was no relationship between biological behavior when compared to: age range, size, breed, time of onset and development, previous ovariohysterectomy and the use of contraceptives. As for location, of the 171 breasts affected, the development of neoplasms of greater malignancy occurred in medial abdominal and inguinal mammary glands. It was demonstrated the relationship between margin involvement and development of pulmonary metastasis. The neoplasic mobility and consistency were identified as prognostic factors for dogs with mammary neoplasms, while the other variables studied were not related to prognosis, while the other studied variables were not related with the prognosis. Data concerning the 36 females suffering from canine mammary neoplasms, which were observed, 13 had tumors of high malignancy (HM), nine of intermediate malignancy (IM), 10 of low malignancy (LM) and four benign (B). The average of calcium levels in the control group was 10.07 mg / dl and magnesium of 2.04 mg / dl. Mean levels of calcium serum of patients in group LM and IM were respectively 8.63 mg / dl and 8.77 mg / dl, both differing statistically (p <0.001) from the control group. The patients in the HM group had a mean calcium of 12.00 mg / dl and differed significantly (p <0.001) from the mean levels obtained in the control group. Regarding the serum levels of magnesium, it was demonstrated statistical difference between the control group (2.04 mg / dl) and the LM groups (p <0.001), IM groups (p = 0.002) and HM groups (p <0.001), with averages of 57 mg / dl, 1.67 mg / dl and 2.56 mg / dl, respectively. Both in the serum levels of calcium and magnesium no statistical differences between control group and group L were shown. It was observed that in animals with mammary neoplasms, the blood values of the studied minerals differed between the first and last collection in the LM groups (p = 0.0125) and HM groups (p = 0,0,0087) in the levels of calcium and in the same LM groups (p = 0.0124) and MA (p = 0.0015) in the levels of magnesium. The results showed that neoplasm mobility and consistency were correlated with malignancy and worse prognosis of the patient, and a strong relationship between margin involvement and lung metastases. Also, dogs with tumors of low malignancy and intermediate malignancy have hypocalcemia and hypomagnesemia, as well as in the cases of malignant neoplasms there is high hypercalcemia and hypermagnesemia, both going back to the physiological levels after six months of surgical excision / A longevidade dos cães tem aumentado a casuística de neoplasmas, sendo que o neoplasma mamário é um dos mais frequentes diagnosticados nesta espécie. As fêmeas caninas são importantes como população de estudo das neoplasias uma vez que existem similaridades entre os neoplasmas mamários desenvolvidos em humanos e caninos, possibilitando desta forma o uso da patologia comparada, buscando maior entendimento da doença. Alterações nos níveis de cálcio e magnésio podem estar relacionadas a presença e ocorrência de neoplasmas mamários, porém não existe uma padronização definida dessas alterações. O trabalho teve como objetivos analisar dados epidemiológicos em pacientes caninos com neoplasmas mamários e determinar níveis de cálcio e magnésio séricos e após exérese; e associar variação de níveis sanguíneos de cálcio e magnésio com a malignidade dos neoplasmas. O estudo teve uma amostra de 53 fêmeas caninas com tumoração em glândula mamária, das quais foram obtidos dados de características descritivas da amostra referentes a resenha do animal, exposição a fatores de risco e do desenvolvimento tumoral, associado as características morfológicas e localização anatômica. Foi realizada exérese das massas tumorais para análise histopatológica avaliando margem cirúrgica e classificando os pacientes segundo comportamento biológico e diferentes graus de malignidade: alta malignidade (AM), malignidade intermediária (MI), baixa malignidade (BM) e benignos (B). Na continuação do estudo, houve uma perda de 17 cães para o estudo de análise de níveis de minerais no período de 180 dias, sendo estudadas 36 fêmeas com neoplasmas mamários e 28 cães saudáveis sem tumores mamários, como controles. Os cães foram avaliados no dia zero (prévio à cirurgia) em relação à massa tumoral e nessa data foi realizada exérese para encaminhamento de peça tumoral para avaliação anatomopatológica e classificados segundo comportamento biológico. A dosagem sérica de cálcio e magnésio (espectrofotometria de absorbância), foi realizada prévia à exérese dos tumores (no dia zero) e aos 60 e 180 dias após o procedimento cirúrgico, no mesmo intervalo de tempo foram avaliadas as dosagens séricas dos minerais no grupo controle. Das 53 cadelas estudadas, 24 apresentavam tumores de alta malignidade, 12 de malignidade intermediária, 13 de baixa malignidade e quatro eram benignos. Os pacientes idosos foram frequentes no grupo de maior malignidade. Não houve relação entre comportamento biológico quando comparado com: faixa de idade, porte, raça, tempo de aparecimento e desenvolvimento ovariohisterectomia prévia e uso de contraceptivos. Quanto a localização, das 171 mamas acometidadas, o desenvolvimento de neoplasma de maior malignidade ocorreu em mamas inguinais e abdominais mediais. Foi demonstrado relação entre comprometimento de margem e desenvolvimento de metástase pulmonar. A mobilidade e consistência neoplásica foram identificados como fatores prognósticos para cães com neoplasma mamário, enquanto as outras variáveis estudadas não foram relacionadas com o prognóstico. Dados referentes às 36 fêmeas caninas portadoras de neoplasmas mamários, que foram acompanhadas, 13 apresentaram tumores de alta malignidade (AM), nove de malignidade intermediária (MI), 10 de baixa malignidade (BM) e quatro benignos (B). A média dos níveis de Cálcio do grupo controle foi de 10,07mg/dl e do magnésio de 2,04mg/dl. Os níveis médios de cálcio sérico dos pacientes do grupo BM e MI foi respectivamente 8,63mg/dl e 8,77mg/dl, ambos diferindo estatisticamente (p< 0,001) do grupo controle. Os pacientes do grupo de AM apresentaram média de cálcio de 12,00mg/dl e diferiram significantemente (p< 0,001) dos níveis médios obtidos no grupo controle. Em relação aos níveis séricos de magnésio foi demonstrado diferença estatística entre o grupo controle (2,04mg/dl) e os grupos BM (p< 0,001), MI (p=0,002) e AM (p< 0,001), com médias de 1,57 mg/dl, 1,67mg/dl e 2,56mg/dl respectivamente. Tanto nos níveis séricos de cálcio quanto de magnésio não foram demonstradas diferenças estatísticas entre o grupo controle e o grupo B. Foi observado que, nos animais com neoplasmas mamários, os valores sanguíneos dos minerais estudados diferiram entre a primeira e última coleta nos grupos BM (p=0,0125) e AM (p=0,0,0087) quanto aos níveis de cálcio e nos mesmos grupos BM (p=0,0124) e AM (p=0,0015) quanto aos níveis de magnésio. Os resultados permitiram concluir que mobilidade e consistência do neoplasma, foram relacionadas com malignidade e pior prognóstico do paciente além de uma forte relação entre comprometimento de margem e metástase pulmonar. Ainda, cães portadores de neoplasias de baixa malignidade e malignidade intermediária apresentam hipocalcemia e hipomagnesemia, assim como nos casos de neoplasmas de alta malignidade ocorre hipercalcemia e hipermagnesemia, ambos retornando aos níveis fisiológicos após seis meses da exérese cirúrgica.

Activin-A is a member of transforming growth factor-β (TGF-β) superfamily of cytokines which includes TGF-βs, Activins, Nodal, bone morphogenetic proteins (BMPs), growth and differentiation factors (GDFs) and anti-Mullerian hormone (AMH). TGF-β, Activin and Nodal are known to activate SMAD2/3, while BMPs and GDFs are known to activate SMAD1/5/8 signaling pathways. Activin-A binds to type II transmembrane serine threonine kinase receptor (ActRIIA or ActRIIB), which in turn activates type I receptor (ActRIB) leading to phosphorylation of SMAD2/SMAD3. Upon phosphorylation, SMAD2/3 forms a complex with SMAD4, which then translocates to nucleus. In the nucleus, SMAD2/3/4 complex, along with other co-factors regulates expression of a large number of genes. Unlike TGF-β, role of Activin in cancer is not well understood. Activin has been shown to be overexpressed in several cancers including metastatic prostate cancer, colorectal cancer, lung cancer, hepatocellular carcinoma and pancreatic cancer. Activin signaling has been shown to promote aggressiveness of esophageal squamous cell carcinoma and enhancing skin tumorigenesis and progression. Nodal, which binds to the same set of receptors, has also been shown to be overexpressed in several cancers. However, role of Activins in breast cancer progression is not well studied. Activin is expressed by normal breast epithelium and is known to play a role in mammary gland development. Earlier, a study had reported downregulation of Activin signaling in breast tumors. On the contrary, increased serum level of Activin has been reported in women with metastatic breast cancers. It is pertinent to mention here that TGF-β, which has been implicated in the progression and metastatic spread of breast cancers, also functions through the same set of downstream effectors- SMAD2 and SMAD3. Hence we wanted to evaluate the status of Activin signaling pathway in breast tumors and investigate its functional role in cancer progression. Gene expression profiling of 80 breast tumors and 20 normal samples was earlier performed in our laboratory revealed overexpression of INHBA in tumors compared to normal tissue samples. An independent set of 30 tumor and 15 normal samples were used to verify these results. Real-time PCR analysis revealed around 11.31 fold upregulation (p<0.001) of INHBA in breast tumors in comparison to normals. While no change in expression of INHA was observed, INHBB was found to be significantly downregulated in tumor samples. These results indicated upregulation of Activin-A in breast tumors. Further, a significant upregulation of ACVR2A and SMAD2 which act as signal transducers of Activin signaling pathway, was observed in breast tumors. Interestingly, while an increase in the expression of TGF-β1 was observed, TGFBR2 was found to be significantly downregulated in breast tumors. In addition, PCR analysis revealed significant downregulation of FST, β-glycan, IGSF1 and IGSF10, which act as negative regulators of Activin signaling pathway. Functional antagonism between TGF-β/Activin and BMP signaling pathway has been shown in both development and disease. Further analysis revealed that various BMPs including BMP2, BMP4 and BMP6 are downregulated in breast tumors compared to normal tissue samples. Various components and regulators of BMP signaling pathway were also found to be deregulated, indicating suppression of BMP signaling in breast tumors. To evaluate whether Activin signaling is active in breast tumor cells, immunohistochemistry with another set of 13 normal and 29 tumor samples was performed. Immunohistochemistry analysis revealed that most of the tumors have higher levels of Activin-A compared to normals tissues. Interestingly, no significant changes in expression of Activin-A was observed between normals and low grade tumors, suggesting that Activin-A may play an important role towards the late stages of the disease. In good correlation, breast tumors showed increased phospho SMAD2 and phospho SMAD3 levels compared to normal tissues. Also, in the same set of tumors, BMP2 staining showed a reduced expression pattern compared to normal tissues. Expression of inhibin in some normal and breast tumor samples revealed that most of the tumor samples have lower levels of inhibin compared to normal tissues. In order to understand the role of Activin-A in cancer progression, a panel of cell lines was selected. Treatment of cells with Activin-A resulted in activation of canonical SMAD as well as non-canonical Erk1/2 and PI3K signaling pathways. However, Activin-A treatment did not lead to activation of TAK1/p38 MAPK pathway. To begin with, it was important to evaluate effect of Activin-A on proliferation of various cell lines. Primarily, SMAD2/3 signaling pathway inhibits proliferation of normal epithelial cells, and hence, it is considered to have a tumor suppressive role. owever, this signaling pathway remains intact in most ( 98%) of the breast cancers. BrdU incorporation assay showed that Activin-A does not promote proliferation of cells under monolayer culture conditions. However, soft agar assay results showed that Activin signaling promotes anchorage independent growth of cancer cells. TGF-β is widely known as an inducer of epithelial mesenchymal transition (EMT). Also, EMT is considered to be a prerequisite for epithelial cells to undergo migration and invasion. During EMT, cells loose epithelial characteristics and acquire mesenchymal features along with cytoskeletal rearrangement. Treatment of cells with Activin-A resulted in downregulation of E-cadherin and upregulation of various mesenchymal markers. In addition, confocal microscopy imaging revealed a mesenchymal morphology of cells treated with Activin-A. Also, collagen gel contraction assay results indicated that Activin-A enhances the contractile property of HaCaT cells significantly. Cells undergone EMT are believed to acquire migratory and Invasive behaviour. In agreement with this, both scratch assay and trans-well migration assay showed that Activin-A enhances the migration of various cell lines. Further, Trans-well matrigel invasion assays were performed to assess how Activin affects invasion of various cancer cells. Matrigel invasion assay results showed that Activin-A enhances invasion of various cancer cell lines significantly. Also, RT-PCR, zymography and Luciferase assay results showed that Activin-A induces MMP2 expression. As described earlier, Activin-A activates both canonical as well as non canonical signaling pathways. In this direction, it was interesting to investigate the contribution of SMAD signaling pathway in pro-tumorigenic actions of Activin-A. Inhibiting SMAD3 activity either by its stable knockdown or by using a SMAD3 specific small molecule inhibitor revealed that Activin-A regulation of EMT markers is SMAD3 dependent. Further, it was observed that SMAD3 contributes significantly in mediating Activin-A induced migration and invasion. Hence, it is likely that SMADs may play an important role in breast tumor progression. Next, stable overexpression of Activin-A in MCF-7 or its knockdown in MDA-MB-231 and H460 cells was performed to assess the effect of Activin-A on the behaviour of these cells. BrdU assay indicated no change in proliferation of cells upon overexpression or knockdown of Activin-A. However, soft agar assay results showed that Activin-A expression affects anchorage independent growth of these cells. MCF-7 cells are generally considered to be less aggressive in their tumor forming ability. Activin-A overexpressing MCF7 cells and control cells were respectively injected into right and left flank of immunocompromised mice and followed till the tumors reached to a prominent size. Our results show that Activin-A overexpressing MCF-7 cells have better tumor forming ability in comparison to control cells. In contrast to MCF-7 cells, MDA-MB-231 cells are known to be aggressive in their tumorigenic potential. In order to understand the effect of Activin-A knockdown on the tumor forming ability in MDA-MB-231 cells, 0.5 million cells (optimal cell number generally used is 1-2 million) were injected subcutaneously in immunocompromised mice. The results showed that while control cells gave rise to a tumor in 7 out of 10 animals, Activin-A knockdown cells could form a tumor in only 3 out of 10 animals. Also, the tumors formed by control cells were significantly larger by weight as compared to tumors formed by knockdown cells. Further, immunohistochemistry showed that tumors formed by MCF-7 cells overexpressing Activin-A have higher Ki-67 percentage as compared to control tumors. One of the factors known to be important for tumor growth is VEGF, which leads to recruitment of blood vessels and hence providing nourishment to the tumor cells. Hence Activin-A regulation of VEGF expression was evaluated next. Activin-A treatment or its stable overexpression in MCF-7 cells resulted in increased VEGF expression in these cells. This was also confirmed by VEGF promoter activity assay. To assess if Activin-A can play a role in metastatic spread of cancer cells, tail vein injection of Activin-A overexpressing MCF-7 cells was performed in immunocompromised mice. Even though no significant difference was found in the number of nodules formed by control or Activin-A overexpressing cells, it was observed that Activin-A overexpressing cells formed much bigger nodules as compared to the control cells. This suggests that Activin-A may play an important part in the establishment of metastases from the disseminated cancer cells. Tumor forming ability of cancer cells and aggressiveness of various cancers has been associated with the presence of cells having stem-like phenotype. In this direction, CD44high and CD24low expression status was analysed upon overexpression and knockdown of Activin-A in MCF-7 and MDA-MB-231 cells respectively. FACS analysis of Activin-A overexpressing MCF-7 cells and Activin-A knockdown MDA-MB-231 cells shows that Activin-A expression leads to enrichment of breast cancer stem-like cells. In conclusion, this study highlights the importance of Activin-A signaling pathway in the progression of breast tumors. It is also important to note the role of SMAD signalling in the progression of breast cancers since these effectors are common between TGF-β, Activin and nodal factors, which have been shown to be involved in cancer progression in a context dependent manner.

Indiana University-Purdue University Indianapolis (IUPUI) / Long-term psychosocial consequences of breast cancer are increasingly more important to study as survivors are living longer. However, the survivors do not experience cancer alone; their significant others often suffer just as much if not more than the survivors themselves. In this dissertation, we explore some long-term consequences of cancer within the context of the Social Cognitive Processing Theory (SCPT). SCPT proposes that an individual must be able to discuss their feelings in order to cognitively process a traumatic event, such as cancer. If discussions are hindered, in particular by a significant other, then one will be unable to work through his/her concerns, leading to poor psychological outcomes, such as depression and fear of recurrence. The purpose of this dissertation is to use SCPT to identify causal mechanisms of depressive symptoms and fear of recurrence using a large sample of young breast cancer survivors and their partners. For one paper, we also included a large set of older participants for comparison. This dissertation is divided into three distinct articles. Each article tests long-term consequences of breast cancer and its treatment on breast cancer survivors and their partners using SCPT to explain relationships. First we examine the hypothesized predictors of younger breast cancer survivors’ depressive symptoms including the partner variable of depressive symptoms. The second article addresses the partners by predicting their depressive symptoms using SCPT. The third and final article seeks to identify the relationship of predictors and FOR on both survivors and their partners again using SCPT. For survivors, structural equation modeling analyses found significant direct and indirect paths between depressive symptoms and theoretical variables, including social constraints (stb=.266, p<.001) and intrusive thoughts (stb=.453, p<.001). In partners, cognitive processing variables (intrusive thoughts and cognitive avoidance) mediated the relationship between social constraints and depressive symptoms (F(5,498)= 19.385, R2=.163, p<.001). And finally, cognitive processing mediated the relationship between social constraints and fear of recurrence both for survivors [F(3,213)= 47.541, R2=.401, p<.001] and partners [F(3,215)= 27.917, R2=.280, p<.001). The evidence from these studies supports the use of SCPT in predicting depressive symptoms and fear of recurrence in both long-term survivors and partners.

The word "cancer" has different meanings for different people. In general, it is synonymous with fatality, either imminent or in the forseeable future. How each person perceives and attributes meaning to this personal experience, varies according to idiosyncratic factors. These factors are constituted by each individual's unique internal make up and by external influences and it is the combination of the multiplicity of factors that bring about the personal attributions of meaning for each individual. The thesis examines the attributions of meaning of a sample of 42 women with breast cancer, through administration of a semi-structured interview and questionnaire, with follow up interviews. The theoretical concepts which are explored, examine the shift away from the traditional, Newtonian, linear-causal, neutral observer model (as in the traditional medical model), towards an ecosystemic, a-causal, contextual, holistic stance. Ecosystemic thinking is utilised in this research work, and this way of thinking is applied to the findings. In addition, a qualitative, descriptive approach is adopted, so that an in depth emphasis rather than a quantitative, empirical view of the patients in the sample, is undertaken. The applied questionaire focuses on the patient's experience of cancer diagnosis, with more specific reference to the side effects of the chemotherapy. The emphasis is towards the issue of anticipatory nausea and emesis and the possible use of hypnosis in relation to these effects. Each patient's attribution of meaning to these aspects forms the core of the thesis. The study discloses the wide variety of attributions of meaning held by different women in a similar predicament towards different aspects of that predicament. Concomitantly, the study highlights the limitations of the traditional, medical model which contribute to diminishing the personal understanding of each patient, and the impact of this on both treatment and outcome for each patient. / Psychology / D.Phil. (Psychology)

Células tumorais desenvolvem diversas estratégias para escapar da identificação e eliminação pelo sistema imune. Dessa forma, a investigação dos mecanismos envolvidos na comunicação celular no microambiente tumoral e na desregulação local do sistema imune é crítica para uma melhor compreensão da progressão da doença e para o desenvolvimento de alternativas terapêuticas mais eficazes. Nós aqui demonstramos que SIGIRR/IL-1R8, um importante regulador negativo de receptores de Interleucina-1 (ILRs) e receptores do tipo Toll (TLRs), apresenta expressão aumentada em uma linhagem celular epitelial mamária transformada pela superexpressão do oncogene HER2 e em tumores primários de mama, e promove o crescimento tumoral e metástase através da modulação da inflamação associada ao câncer e da atenuação da resposta imune antitumoral. Observamos que IL-1R8 tem sua expressão correlacionada com HER2 em tecidos mamários e sua alta expressão é fator de pior prognóstico em câncer de mama de baixo grau. Notavelmente, níveis aumentados de IL-1R8 foram observados especialmente nos subtipos HER2+ e Luminais de tumores de mama, e sua expressão aumentada em células epiteliais de mama transformadas por HER2 diminui a ativação da via de NF-&#954;B e a expressão de diferentes citocinas pro-inflamatórias (IL-6, IL-8, TNF, CSF2, CSF3 e IFN-&#946;1). Meio condicionado de células transformadas por HER2, mas não de variantes celulares com o gene IL-1R8 silenciado, induz a polarização de macrófagos para o fenótipo M2 e inibe a ativação de células NK. Em um modelo murino transgênico de tumorigênese espontânea mediada por HER2, MMTV-neu, verificamos que a deficiência de IL-1R8 (IL-1R8-/-neu) retardou o aparecimento de tumores e reduziu a incidência, a carga tumoral e a disseminação metastática. Contudo, não foram observadas diferenças significativas no crescimento tumoral quando animais IL-1R8-/-neu receberam medula óssea de animais IL-1R8+/+, confirmando um papel importante da expressão de IL-1R8 em células não hematopoiéticas na tumorigênese da mama. Tumores IL-1R8+/+neu apresentaram maiores níveis de citocinas pró-inflamatórias como IL-1&#946; e VEGF, e menores níveis da citocina imunomodulatória IFN-&#947;. Além disso, tumores que expressavam IL-1R8 apresentaram menor infiltrado de células NK maduras, células dendríticas (DCs) e linfócitos T-CD8+ e um maior infiltrado de macrófagos M2 e linfócitos T-CD4+. Coletivamente, esses resultados indicam que a expressão de IL-1R8 em tumores de mama pode representar um novo mecanismo de escape da resposta imune e suportam IL-1R8 como potencial alvo terapêutico. / Tumor cells develop numerous strategies to fine-tune inflammation and avoid detection and eradication by the immune system. Identification of new players that regulate the cellular crosstalk within the tumor microenvironment and promote local immune dysregulation is critical to understand disease progression and to improve therapeutic strategies. Here, we demonstrate that SIGIRR/IL-1R8, a negative regulator of IL-1R and TLRs, is up-regulated in a HER2-transformed epithelial mammary cell line and in primary breast tumors and promotes tumor growth and metastasis by modulating cancer-related inflammation and impairing anti-tumor immunity. IL-1R8 expression is correlated with HER2 in mammary tissue, and higher tumor IL-1R8 expression is a poor prognostic factor in lower grade breast tumors. Notably, higher levels of IL-1R8 expression were observed in HER2+ and Luminal breast tumor subtypes and IL-1R8 up-regulation in HER2-transformed mammary epithelial cells inhibited NF-&#954;B activation and the expression of pro-inflammatory cytokines (IL-6, IL-8, TNF&#945;, CSF2, CSF3, IFN-&#946;1). Conditioned medium from HER2-transformed cells, but not from IL-1R8 knockdown variants, induced M2-macrophage polarization and inhibited natural-killer (NK) cell activation. IL-1R8 deficiency in a transgenic mouse model of breast tumorigenesis (MMTV-neu) significantly delayed tumor onset and reduced tumor incidence, burden and metastasis. No significant differences in tumor growth were observed when IL-1R8-/-neu mice were transplanted with bone marrow from IL-1R8+/+ animals, confirming an important role for IL-1R8 expression in non-hematopoietic cells during breast tumorigenesis. IL-1R8+/+neu mammary tumors presented higher levels of pro-inflammatory cytokines such as IL-1&#946; and VEGF, but lower levels of IFN-&#947;. Besides, a lower infiltrate of mature NK cells, dendritic cells (DCs) and CD8+ T cells but higher infiltrate of M2-macrophages and CD4+ T cells were present in IL-1R8 expressing tumors. Collectively, our results support IL-1R8 expression as a novel tumor immune escape mechanism in breast cancer and putative target for immunotherapy.

The word "cancer" has different meanings for different people. In general, it is synonymous with fatality, either imminent or in the forseeable future. How each person perceives and attributes meaning to this personal experience, varies according to idiosyncratic factors. These factors are constituted by each individual's unique internal make up and by external influences and it is the combination of the multiplicity of factors that bring about the personal attributions of meaning for each individual. The thesis examines the attributions of meaning of a sample of 42 women with breast cancer, through administration of a semi-structured interview and questionnaire, with follow up interviews. The theoretical concepts which are explored, examine the shift away from the traditional, Newtonian, linear-causal, neutral observer model (as in the traditional medical model), towards an ecosystemic, a-causal, contextual, holistic stance. Ecosystemic thinking is utilised in this research work, and this way of thinking is applied to the findings. In addition, a qualitative, descriptive approach is adopted, so that an in depth emphasis rather than a quantitative, empirical view of the patients in the sample, is undertaken. The applied questionaire focuses on the patient's experience of cancer diagnosis, with more specific reference to the side effects of the chemotherapy. The emphasis is towards the issue of anticipatory nausea and emesis and the possible use of hypnosis in relation to these effects. Each patient's attribution of meaning to these aspects forms the core of the thesis. The study discloses the wide variety of attributions of meaning held by different women in a similar predicament towards different aspects of that predicament. Concomitantly, the study highlights the limitations of the traditional, medical model which contribute to diminishing the personal understanding of each patient, and the impact of this on both treatment and outcome for each patient. / Psychology / D.Phil. (Psychology)