Major Histocompatibility Complex (MHC) Class I molecules present peptides to CD8⁺ T cells and are essential for most adaptive immune responses. The first described-spliced tapasin (“isoform 1”) plays a critical role in MHC-I antigen presentation by facilitating peptide loading onto MHC-I molecules in the endoplasmic reticulum (ER). This thesis examines the expression, localization and function of two novel, alternatively-spliced isoforms of human tapasin that lack exon 7 (“isoform 2”) or both exons 6 and 7 (“isoform 3”). Isoform 1 contains a di-lysine ER-retention motif; the two novel isoforms encode different carboxy (C) termini that lack this motif. It was hypothesized that isoforms 2 and 3 would function in MHC-I cross-presentation of exogenous antigens in non-ER compartments. Isoform 2, like isoform 1, was found to be mainly ER-localized; however, both these isoforms were also found to co-localize in smaller amounts with the trans Golgi network and endo/lysosomes by confocal microscopy. Isoform 3 lacks a transmembrane domain and was found to be secreted from cells as well as being found within the ER. All isoforms were widely expressed at the RNA level in many tissues and cell types; however, mature dendritic cells (DCs) expressed the highest levels of all three isoforms, consistent with the high cross-presenting abilities of DCs. Both isoform 1 and 2 stabilized the transporters associated with antigen processing (TAP) in murine tapasin-/- cells, but isoform 3 did not due to its missing transmembrane domain. Isoform 1 and 2 mediated very similar effects on endogenous MHC-I presentation of self and viral peptides, on surface MHC-I thermostability, and on MHC-I maturation rates. Isoform 3 was found to decrease loading of exogenous peptides onto MHC-I. None of the isoforms influenced cross-presentation of the soluble antigen ovalbumin in a mouse dendritic cell line. This thesis also examines the effect of antigen presentation machinery (APM) re-expression in MHC-I-deficient tumor cell lines, B16F10 and CMT.64, which are deficient in TAP and tapasin. Virally-driven TAP1 and Tapasin expression increased MHC-I expression in the tumor cell lines, augmented tumor cell immunogenicity, and decreased tumor growth in vivo due to increased tumor cell elimination by the immune system. / Science, Faculty of / Zoology, Department of / Graduate

Cutaneous malignant melanoma is an aggressive form of skin cancer, characterized by strong chemoresistance and poor patient prognosis. The molecular mechanisms underlying its resistance to chemotherapy remain unclear but are speculated to involve dysregulation of apoptosis and reinforcement of survival signaling. In this work, we show that aberrant expression of two key proteins, PUMA and p-Akt, is associated with melanoma tumor progression and poor patient survival. We report that PUMA expression is reduced in melanoma tumors compared to dysplastic nevi, while p-Akt expression is elevated in melanoma tissue compared to dysplastic nevi. We propose a two-pronged therapeutic strategy of (1) boosting PUMA expression and (2) inhibiting Akt phosphorylation. We demonstrate that exogenous overexpression of PUMA, via adenoviral-mediated gene expression (ad-PUMA), forces melanoma cells to undergo rapid mitochondrial-mediated apoptosis in vitro. We also report that a small molecule Akt inhibitor, API-2, greatly inhibits melanoma cell growth in vitro. Using a SCID mouse melanoma xenograft model, we show that combination treatment of ad-PUMA and API-2 dramatically suppresses tumor growth in an additive manner, leading to over 80% growth inhibition compared to controls. We also investigate the role of NF-κB overexpression in melanoma. Our lab previously reported that expression of the p50 subunit of NF-κB, in particular, correlates with melanoma progression and poor patient survival. Here, we use cDNA microarray analysis to show that p50 overexpression upregulates IL-6 in melanoma cells. We further demonstrate that p50-mediated IL-6 expression stimulates the growth of endothelial cells in vitro and promotes angiogenesis in vivo. This work supports the hypothesis that melanoma cells exploit multiple mechanisms to sustain a survival advantage, including: 1) suppression of apoptosis (via PUMA down-regulation), 2) increased activation of survival pathways (via increased p-Akt), and 3) upregulation of pro-angiogenic factors (via p50-mediated IL-6 induction). This work suggests that the specific targeting of one or more key mediators of these processes may be an effective therapeutic strategy for treating malignant melanoma. / Medicine, Faculty of / Medicine, Department of / Experimental Medicine, Division of / Graduate

The study of rhabdomyosarcomas induced by nickel sulphide was undertaken in order to investigate their growth and responsiveness characteristics and to evaluate their possible usefulness as experimental tumour systems. A study was also made on the carcinogenic specificity of nickel sulphide. Intramuscular injections of 0.5 to 20 mg. of Ni₃S₂ resulted in tumours after two to six months, which grew fairly rapidly, once palpable. On transplantation they proved to be highly malignant, causing 100 per cent takes within approximately two weeks and death of the host within three to eight weeks. Detailed histological study was performed on many sections of tumour and muscle in order to establish identity of the rhabdomyosarcomas and to observe such cytological phenomena as muscle degeneration, tissue disruption and development of anaplasia. The carcinogenic activity of Ni₃S₂ was emphasized by the rapidity of tumour induction observed after very low doses, while the difference in latent periods suggested some correlation between dose and response. Injections of Ni₃S₂ into body organs illustrated the extreme toxicity of the substance in individual tissues. Although results were somewhat inconclusive within the time limit of the experiment, the general tenor of the data suggested that Ni₃S₂ had a toxic rather than tumourigenic action on most tissues. The appearance of rhabdomyosarcomas when the compound was in contact with abdominal or leg musculature gave evidence that nickel sulphide might have some specificity for striated muscle. Preliminary experiments with NiS indicated that its carcinogenicity, if any, was considerably less than that of Ni₃S₂, with different solubility in muscle being a possible explanation. Several of the induced tumours were used for metabolic and experimental therapy studies with various compounds. Numerous experiments indicated that the tumour was essentially unreliable for such studies since growth rates and response were not reproducible in different tumour generations. However, some general trends were noted. Response to the corticoids ranged from residual to complete inhibition of many tumours during the period of treatment with Cortisol or cortisone. Subcutaneous injections of testosterone showed acceleration of growth in some tumour lines. Tests with the Vinca alkaloids suggested some correlation with clinical anti-tumour effects, indicating an increased effectiveness of both Vinblastine and Vincristine when administered during the first week after transplantation. / Medicine, Faculty of / Cellular and Physiological Sciences, Department of / Graduate

The purpose of this cross-sectional ethnography was to develop theory and knowledge about how women in Canada live with breast cancer. Cross-sectional ethnography describes a number of individuals from a cross-section of a culture or subculture for a unit of study (Boyle, 1994). A cross-section of women with breast cancer were studied, not an interacting group of women with breast cancer (Werner & Schoepfle, 1987 ). As a result of counselling women with breast cancer over a period of two years, I have learned that despite the differing treatment protocols and differing kinds and stages of breast cancer, women with breast cancer are members integrated into a subculture which has many common words, phrases, images, and themes. Thirteen women with breast cancer form the unit of study for this research. Cancer is a complex array of diseases which develop in 25% of the population; one woman in nine is diagnosed with breast cancer in Canada (Holland, 1989), and one woman in three with breast cancer will die of metastases (Elliott, Rahimi, Tremblay, Shenoy, Rossiter, & Saulnier, 1997). The incidence of breast cancer is increasing annually (O’Donnell, Coughlin, & LeMarbre, 1992); breast cancer is the most frequent cancer in women and is the leading cause of death in women between the ages of 35 and 55 (Andrulis, 1997). Secondary goals of this research were to have the emergent knowledge published to provide increased choices and actions for those newly diagnosed with breast cancer, and to provide data, facts and information to counsellors, professionals and others working and living with breast cancer. Psychological distress in women with breast cancer is often translated into psychopathology by those following the medical model in breast cancer treatment (Mathieson, 1991). Depression and anxiety diagnoses are predominant in women with breast cancer, with rates of depression diagnoses as high as 75% (Massie & Holland, 1989). A study by Garcia, Cristal-Luna, Li, Uai, Gonzalez, Tarmayo, Masadao, Lola, and Matumog (1997) concluded that the presence of cancer disrupts almost every aspect of an individual’s life and that depressive symptoms were experienced throughout the course of chemotherapy. Symptoms experienced by breast cancer patients are often translated by DSM IV criteria into psychiatric disorders, most often depression and anxiety (Derogatis, Abeloff, & Melisaratos, 1983). After counselling women in two cancer Clinics, I began to understand that the experience of having breast cancer imposes many stresses which are in fact, normal, given the context of the cultural stigmata and traumata which result from the diagnosis and treatment o f this disease. Women caught up in the shock of diagnosis and the invasive treatments alluded to colloquially as “slash, burn, and poison” blamed themselves. Most of all they asked: “How do other women live with breast cancer?" This study is an initial response to that question. Thirteen women who had been diagnosed with breast cancer participated in this study. A cross-sectional ethnography was the research method. Ethnographic questioning (Spradley, 1979) is used to organize and analyse data. Using the North American culture as background, and the subculture of those with breast cancer as foreground, ethnographic questioning elicited the shared contexts of 13 women’s life worlds as they described their experiences after a diagnosis of breast cancer. This ethnographic method facilitated the analysis of the women’s experiences by searching for cognitive and behavioural themes of meaning in the women’s verbal descriptions. Dominant themes which emerged and recurred through the 13 interviews were: 1) adaptation to ambiguity and stress; 2) sadness and anger; 3) fear and terror; 4) lack of support; 5) dehumanization; 6) disempowerment and trivialization; 7) shame and stigma; 8) coping; 9) minimization and denial; 10) it (cancer) changes everything; 11) the game of survival; 12) the doctor is God; and 13) metaphors, images, and other cultural symbols specific to those with a diagnosis of breast cancer. Conclusions recommend the inclusion of these and other themes in the psychotherapeutic frameworks utilized by those counselling individuals with a diagnosis of breast cancer. / Graduate

The purpose of this study was to explore the socioeconomic needs and concerns of a group of new breast cancer patients and their families with consideration of changes in roles and relationships and patient's feelings about self. The study was conducted in co-operation with the A. Maxwell Evans Clinic, a cancer treatment centre under the direction of the Cancer Control Agency of British Columbia. The scope of this study was restricted to new breast cancer patients referred to the New Patients Clinic in May, 1978 and their primary care-givers. In this study, the primary care-givers were family members most responsible for the patient's rehabilitation. The sample consisted of 16 patients and 14 primary care-givers. Two of the patients' primary care-givers were not available at the time of the interview. The sample included patients with breast cancer in Stages 1, 2, 3 and 4. One interview schedule was designed for the patient and a shorter form for the primary care-giver. An open-ended question about the patients and primary care-givers' greatest concerns were included to identify needs not covered by scheduled topics and to give respondents an opportunity to expand and priorize concerns. Socioeconomic change was defined in terms of changes in place of residence, work activities outside the home, family roles and responsibilities, relationships with family and friends, and feelings about self. The findings indicated that the area of greatest change was in family roles and relationships. Most primary care-givers were interested in talking to the interviewer about some anxieties concerning their new role as primary care-giver. Some primary care-givers also were interested in more information about how to create a rehabilitative environment for the patient. All patients were generally positive toward the Clinic. Several patients expressed a number of suggestions for improving support services and offered ideas about . the attitudes of significant others which affect the patient's sense of well-being and ability to recover. The researcher makes some recommendations for enhancing and developing supportive services for the consideration of the medical team and the specialized social services department in a cancer clinic. The recommendations include approaches to help families recognize and develop new roles to help the patient recover. / Arts, Faculty of / Social Work, School of / Graduate

In Africa, Prostate cancer (PCa) is the most frequently diagnosed solid organ tumour in males and use of prostate specific antigen (PSA) is presently fraught with diagnostic inaccuracies. Not least, in a multi-ethnic society like South Africa, proteome differences between African, Caucasian and Mixed-Ancestry PCa patients are largely unknown. Hence, discovery and validation of affordable, non-invasive and reliable diagnostic biomarkers of PCa would expand the frontiers of PCa management. We have employed two high-throughput proteomics technologies to identify novel urine- and blood-based biomarkers for early diagnosis and treatment monitoring of prostate cancer in a South African cohort as well as elucidate proteome differences in patients from our heterogeneous cohort. We compared the urinary proteomes of PCa, Benign Prostatic Hyperplasia (BPH), disease controls comprising patients with other uropathies (DC) and normal healthy controls (NC) both by pooling and individual discovery shotgun proteomic assessment on a nano-Liquid chromatography (nLC) coupled Hybrid Quadrupole-Orbitrap Mass Spectrometer platform. In-silico verification of identified biomarkers was performed using the Human Protein Atlas (HPA) as well as SRMAtlas; and verified potential biomarkers were experimentally prevalidated using a targeted parallel reaction monitoring (PRM) proteomics approach. Further, we employed the CT100+ antigen microarray platform to assess the differential humoral antibody response of PCa, DC and BPH patients in our cohort to a panel of 123 tumour-associated cancer antigens. Candidate antigen biomarkers were analyzed for ethnic group variation in our cohort and potential cancer diagnostic and immunotherapeutic inferences were drawn. Using these approaches, we identified 5595 and 9991 non-redundant peptides from the pooled and individual experiments respectively. While nine proteins demonstrated ethnic trend, 37 and 73 proteins were differentially expressed by pooled and individual analysis respectively. All 32 verified biomarkers were prevalidated with parallel reaction monitoring. Good PRM signals for 12 top ranking biomarker was observed, including PSA and prostatic acid phosphatase. We also identified 41 potential diagnostic and immunotherapeutic antigen biomarkers. Proteogenomic functional pathway analyses of differentially expressed antigens showed similar enrichments of biologic processes. We identified herein novel urinary and blood-based potential diagnostic biomarkers and immunotherapeutic targets of PCa in a South African PCa Cohort using multiple proteomics approaches.

Research report in partial fulfillment for the degree of MMed (Pulmonology), faculty of Health Sciences, University of the Witwatersrand / Introduction: cancer remains the most common malignancy, with an estimated 1.04 million new cases each year worldwide, accounting for 12.8% of new cancer cases. Of these cases, 58% occur in the developing world. Lung cancer is the most common cancer among men, with an incidence of approximately 37.5 new cases per million. The incidence is lower in women, at 1.08 cases per million population. Lung cancer is the leading cause of morbidity and mortality in the world. There is evidence in the literature of racial and gender differences in the distribution of lung cancer. However data from South Africa is sparse. Aim: The primary objective of this study was to investigate whether differences existed in demographic and histological features of lung cancer when comparing black versus white patients with cancer of the lung in Johannesburg Methods: A retrospective case record review of 817 patients presenting to the pulmonology units of the three hospitals, between January 1992 and December 1998, was undertaken. Demographic, clinical, laboratory and histological features were captured and analyzed, using the GraphPad InStat 3.10 program for Windows. The histological cell types of lung cancer were characterized using the 1981 WHO classification. Results: A total of 817 patients with lung cancer were enrolled in the study. The age group of the total sample ranged between 26-92 years with a mean±SEM of 61.0±0.04 years. There were 574 (70.3%) male patients versus 222 (27.2%) female patients. The remaining 21 (2.6%) patients had no data recorded with respect to their gender. The racial stratification of these patients in decreasing order of frequency was whites 441 (54.0%), blacks 337 (41.3%), mixed race 24 (3.0%) and Indians 15 (1.8%). The study group consisted of the 778 black and white patients. The black patients were younger (mean ±SEM, 57.3±0.5years) than the white patients (mean ±SEM, 64.0±9.9) irrespective of gender (p <0.001). Overall 632 patients were smokers, either current or ex-smokers. The amount of cigarettes consumed was significantly higher in white patients compared to black patients (mean pack years for white patients was 52.7 ± 27.1 versus 21.7± 14.3 pack years for black patients (p <0.001)). This difference was irrespective of gender. The mode of diagnosis in the 778 lung cancer patients was bronchoscopy in the majority 479 (54.0%), followed by sputum cytology in 152 (18.3%) and fine needle aspiration in 105 (12.7%). Tissue biopsy was utilized to diagnose 23 (2.7%) of the lung cancers. In some cases more than a single modality of diagnosis was utilized. The radiological features of the 778 lung cancer patients varied. The majority had a mass on chest radiograph; a lung mass in 357 (46.5%) patients, a hilar mass in 166 (21.6%), and a mediastinal mass in 18 (0.3%) patients. Pleural effusions were found in 82 (10.7%), lung atelectasis in 78 (10.2%), an infiltrate in 29 (3.8%) and consolidation in 25 (3.3%). Histological cell types of lung cancer in the 778 patients consisted of the following, in descending order of frequency; squamous cell carcinoma in 341 (43.8%), adenocarcinoma in 167 (21.5%), small cell carcinoma in 129 (16.6%) and large cell carcinoma in 68 (8.7%) of the cases. Other histological cell types accounted for 73 (9.4%) of the patients. Small cell carcinoma was overall more common amongst white patients especially males and in black patients it was exclusively in females (p<0.0005). However the black female patients tended to have more small cell carcinoma (40 (45.5%)), compared to the white female patients who had more squamous cell carcinoma (54 (45.0%)) in the majority. There was a small proportion of patients considered to be operable with intent to cure -74 (9.5%). This was a poor operability rate compared to an expected operability rate of 15-20%. This rate was as distressing when divided along racial lines; 29 (8.6%) of black patients and 45 (10.2%) of white patients being considered operable. Discussion: The demographics of the study group were different. The black patients tended to be significantly younger and smoked less cigarettes compared to the white patients. There was a significantly greater number of male patients with lung cancer than female patients. This difference was irrespective of race. The ranked frequency of histological subtypes was similar in both race groups. However, the black female had more small cell carcinoma, compared to white females with a preponderance of squamous cell carcinoma. The operability of all lung cancer patients, irrespective of gender and race, was dismal at 9.5%, compared to the standard norm of 15-25% operability rate. This is worrying when one considers the fact that surgery is the means to a cure. It either suggests there is a delay in seeking medical care and/or the lack of medical resources to permit screening and early diagnosis of the malignancy. Conclusions: This study did not demonstrate any ranked frequency differences in histological cell type distribution between black and white patients. Squamous cell carcinoma was the most common histological cell type regardless of race. Small cell carcinoma was significantly more common among white patients, especially the males while among the black patients it was exclusively found in the females. Black patients with lung cancer tended to present at an earlier age. Black females were less likely to develop lung cancer when compared with the white females. The black patients smoked fewer cigarettes than the white patients irrespective of gender. The operability of our patients, in the study, was poor in all race groups.

Peru is a South American nation with a growing and aging population of 31 million people with a life expectancy at birth of 76.7 years. The country is divided into 25 regions, 79% of the population is urban, and Lima, the capital, concentrates more than a third of the population.1 Although Peru is an upper-middle-income country, health expenditure represents only 5.1% of the gross domestic product, which is lower than the average of Latin America and the Caribbean (LATAM) (8.56%).2 Out-of-pocket health expenditure is 30.9%.3 Peru has a comprehensive National Cancer Plan and two population-based cancer registries in Lima and Arequipa. / Revisión por pares

Thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Counselling Psychology at the Zululand University, South Africa, 2012. / When a child is diagnosed with paediatric cancer, the entire family is affected. Relating to the impact of this new family diagnosis, it is often the siblings of the ill child who carry the greatest hidden burden of stress. Although there is a sound and growing body of international research pertaining to the sibling cancer experience, South African research on this topic is almost non-existent, and there is still much to be learnt. As a result, the present study aimed to gain a better understanding of the cancer experience from the perspective of South African siblings. To this end, semi-structured interviews were conducted with 10 healthy siblings who have a brother or sister who was diagnosed with paediatric cancer. The sibling sample comprised of 4 boys and 6 girls (Aged 8-18) who reside in the Western Cape Province of South Africa. Data collected through the sibling interviews was analysed by means of thematic analyses. Five overall themes evolved from the siblings’ narratives. These themes related to the concept of cancer; concerns and worries; emotional experiences; changes; and resources and coping. Within each of these overarching themes, various sub-themes were also noted. In order to gain a holistic understanding of the sibling cancer experience, the five themes were contextualised and discussed in terms of various developmental theories including: Erikson’s psychosocial (socio-emotional) developmental theory; Piaget’s cognitive developmental theory; and Bronfenbrenner’s Bioecological systems theory. Although findings relating to the cancer experience for siblings in the present study did not differ tremendously from those noted in previous research, the results still made a valuable contribution to the existing body of knowledge involving siblings and paediatric cancer. Light was shed on the unique cancer experience for 10 South African siblings, and great insight was gained into their unique emotional worlds. In conclusion the present study’s contributions as well as shortcomings were discussed, and intervention guidelines and recommendations for future research were provided.

Although early detection and treatment of prostate cancer (PC) shows clinical benefit, advanced PCs that progress despite androgen deprivation therapy almost invariably result in castration resistance. This progression is lethal as castration-resistant prostate cancer (CRPC) are intimately associated with metastasis and remains the predominant cause of PC-related fatalities. Increasing evidence reveal a critical role of prostate cancer stem cells (PCSCs) in facilitatin g PC progression and acquisition of androgen independence. Taking advantage of our putative DU145 cell derived-PCSC population, we examined a number of candidate proteins for their contribution to PC progression and CRPC development. We identified three PCSC-specific proteins, BChE, CNTN1 and PCSK9. Butyrylcholinesterase (BChE) is a plasma enzyme known for its role in hydrolyzing ghrelin and bioactive esters, and is associated with altered metabolisms. Serum BChE is reduced in several cancer types. In this thesis we revealed a biphasic alteration of BChE and identified its downregulation at early stage of PC and upregulation at advanced stage PC. In a similar manner, we reported a functional role of CNTN1 in PC advancement. We demonstrate evidence for CNTN1-mediated enhancement of LNCaP cell proliferation in vitro and formation of CRPC in vivo, as well as its oncogenic potency in a prostate-specific CNTN1 transgenic model. Furthermore, we constructed a novel CNTN1-associated gene panel that predicts PC relapse risk with high robustness. IQGAP1 is critical in cytoskeletal dynamics which underlies cancer progression, metastasis, and PCSC biology. We showed IQGAP1 downregulation in both CRPCs and advanced PCs, and constructed a 27-gene signature using differentially expressed genes (DEGs) relative to this downregulation. This IQGAP1-relevant 27-gene panel robustly predicts PC relapse following radical prostatectomy and shows high translational value as a complementary panel to currently available commercial multigene panels. PCSK9 is an important protein in the regulation of cholesterol metabolism but its role in cancer is not known. We provide a comprehensive set of evidence supporting its role in the formation of CRPC, likely via mechanisms involving enhanced intratumoral uptake and sustained AR signalling under androgen-deprived conditions. Importantly, bigenic TRAMP mice deficient in PCSK9 have shown significantly prolonged survival and reduced metastasis. Collectively, we identified four factors with pivotal roles in PC development and progression into CRPC, albeit with different mechanisms. The altered expression of these factors in advanced PC and their widespread impact on a diverse range of mechanisms important in cell proliferation and survival underscores the importance of PCSCs in promoting advanced prostate cancer. Taken together, the findings of this thesis will advance our knowledge on PCSC-relevant pathways and their association with prostate cancer progression and metastasis. / Thesis / Doctor of Philosophy (Medical Science)