Testicular cancer (TC) is the most common cancer affecting men of reproductive age; however treatment with bleomycin, etoposide, and cis-platin (BEP) results in extremely high cure rates. The post-treatment quality of life of TC patients is therefore a major concern. The goal of this study was to determine the effects of BEP on sperm count, motility, and morphology in an animal model. Male Sprague Dawley rats were treated with BEP for 9 weeks. Rats were killed, and the numbers, motility, and morphology of the spermatozoa from the epididymides were analyzed. After BEP treatment, sperm counts decreased by almost 10-fold when compared to control (11.9x107 versus 1.65x107 sperm per epididymis). The percent of spermatozoa that were motile was > 30% lower in the treated group compared to control group. Morphological defects increased significantly in both the midpiece and principal piece of the flagella. These results indicate that BEP treatment has significant effects on spermatogenesis in the rat model.

Despite more conservative surgical treatment for breast cancer, lymphedema and arm dysfunction remain sources of significant morbidity. The study for this thesis was conducted to explore methods for defining and identifying lymphedema and arm dysfunction after treatment for breast cancer. / In order to establish cut-points in the differences in the sizes of arms to define the presence of lymphedema among women previously treated for breast cancer, the distributions of the differences in the sizes of arms, using measures of circumference and volume, among 40 women with no history of breast cancer were determined. The selected cut-points in the differences were defined as the mean plus one, two, or three standard deviations. / A questionnaire (referred to as the Lymphedema Identification Tool) based on self-reported symptoms was developed to identify women with lymphedema. The Lymphedema Identification Tool and the 'Disabilities of the Arm, Shoulder and Hand' (DASH) questionnaire were sent to 596 women previously treated for stage I or II breast cancer and 50 women attended an evaluation session. At this evaluation session, measurements of the sizes of their arms were made and the Lymphedema Identification Tool and the DASH were repeated. This allowed for the evaluation of test-retest reliability, internal consistency reliability, and criterion validity of the Lymphedema Identification Tool. / From these measurements and responses to the questionnaires, the association between arm dysfunction, as assessed by the DASH questionnaire, and the presence of lymphedema, as determined by the measurements of arm sizes and by women's self-report was determined. In addition, through the development of logistic regression models, the Lymphedema Identification Tool, the DASH questionnaire, age at diagnosis, and body mass index were found to predict the presence of lymphedema, as defined by the measurements of arms. / Lymphedema appears to be a condition associated with a spectrum of symptoms and functional impairment varying from mild to severe. This thesis, even though results are preliminary, suggests a methodology for identifying lymphedema and arm dysfunction.

Human nonspecific cross-reacting antigen (NCA), a close relative of the tumour marker human carcinoembryonic antigen (CEA), is also an in vitro homotypic intercellular adhesion molecule capable of inhibiting differentiation when expressed ectopically in myoblasts. Moreover, NCA appears to be overexpressed at the transcriptional level to a greater extent and more frequently in colorectal carcinomas than CEA. This study examines the transcriptional control mechanisms responsible for orchestrating NCA expression. The region within 283 bp upstream of the translational start site of the NCA gene was found to be capable of directing high levels of expression in functional promoter assays. Footprinting experiments identified three cis-acting elements and mobility-shift assays revealed that the first of these elements is bound by USF1 and USF2, and the second two are bound by Sp1 and Sp3. No cis-acting elements corresponding to CEA FP4 or the silencer CEA FP5 of the CEA promoter were detected in the NCA promoter, which may contribute to the differential expression of NCA versus CEA in tumourigenesis.

Tumoricidal activities of nitrogen monoxide (NO) are mediated mainly by its effects on iron metabolism. In the present study we used different exogenous NO congeners to investigate the effects of different redox forms of NO on iron metabolism and cellular proliferation of human K562 erythroleukemia cells. Treatment of K562 cells for 18 h with the nitrosonium ion (NO$ sp+$) donor, sodium nitroprusside (1 mM), decreased mRNA binding activity of iron regulatory factor (IRF), transferrin receptor (TfR) mRNA, TfR number and also iron uptake. However, cellular proliferation was not decreased. On the contrary, treatment of K562 cells with the nitric oxide (NO$ cdot$) donor, S-nitroso-N-acetylpenicillamine (1 mM), slightly increased IRF activity, TfR mRNA level, TfR number and iron uptake. Furthermore, cellular proliferation was decreased. We speculate that NO$ sp+$ may regulate IRF, the key regulatory molecule in iron metabolism, via S-nitrosylation of critical free sulphydryl group(s), while NO$ cdot$ may ligate to FeS cluster in IRF. The new concept of different redox forms of NO opens an interesting possibility of IRF inactivation by NO$ sp+$, which may be a very important step in the inhibition of growth of target tumor cells by activated cytotoxic macrophages.

This population-based multi-centered case-control study of incident postmenopausal breast cancer was carried out in Montreal. Case subjects included all incident histologically confirmed breast cancer among postmenopausal women, age 51--75 years, diagnosed in 1996 and 1997 in all major hospitals. Control subjects had other histologically-confirmed sites of cancer from the same hospital, and were approximately frequency-matched by age to the case subjects. Detailed information was obtained on active smoking and exposure to environmental tobacco smoke (ETS) in the home before the age of 18 and in the workplace as an adult. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) between the risk of postmenopausal breast cancer and various indices of smoking and exposure to ETS. The OR for breast cancer among women with exposure to active smoking only was 0.71 (9596 CI: 0.34--1.48), for early exposure to ETS only, the OR was 1.09 (95% CI: 0.65--1.85), and for occupational exposure to ETS only, the OR was 1.00 (95% CI: 0.53--1.90). When occupational and early exposures to ETS were combined, the OR was 1.40 (95% CI: 0.81--2.40). In summary, I found no associations between the incidence of postmenopausal breast cancer and active smoking or exposure to ETS.

Background. Practice guidelines for screening mammography diverge on the recommended age at which systematic screening should begin for women aged 40 to 69 years. 'Routine' guidelines recommend screening starting at 40 years; 'age-selective', at 50 years and only for younger women who have a first-degree family history of breast cancer. Objectives. (1) To estimate and compare recently-licensed family physicians' adherence to 'routine' and 'age-selective' guidelines in women aged 40 to 69 years, (2) To identify intrinsic physician and practice environment factors which predict referral rates for women aged 50 to 69 years as well as age-selective referral. Study Design. A census sample of 743 recently-licensed family physicians was followed for 18-months of incipient medical practice. Mammograms were identified from physician claims to the Regie de l'assurance-maladie du Quebec for every clinically eligible woman aged 40 to 69 years who had a complete physical examination by a study physician in a community setting (primary care practice). Adherence to 'routine' guidelines was measured as the percent of women with a screening mammogram referred by the study physician in the study period. Adherence to 'age-selective' guidelines was referral rates in older (50-to-69 years) minus younger (40-to-49 years) women. Multiple linear regression was used to identify predictors of mammography referral. Results: Study physicians referred 6% (SD: 10) of younger women and 12% (SD: 15) of older women in their primary care practice. The correlation or ranks of adherence to 'routine' and 'selective' guidelines corresponded poorly (Spearman r = 0.51). Factors positively associated with higher referral rates in women aged 50 to 69 years were female gender, prevention competence, later medical school graduation, the combination of comprehensive inquiry and continuity care, and the extent of community-based care. Negatively associated factors were higher patient volume and shared primar

Adenoviruses have proven to be particularly helpful in unraveling the intricacies of cell growth regulation and apoptosis, greatly increasing our understanding of oncogenesis. At the onset of this work, adenoviruses were thought to induce apoptosis via a p53-dependent cell death pathway exclusively, and we set out to develop an assay system to study the ability of viral proteins to inhibit p53-induced apoptosis. We started using the p53-null human Saos-2 osteogenic carcinoma cells when we found that p53 expression led to rapid cell death. The morphology of these cells by electron microscopy confirmed that death was by apoptosis and this death was significantly reduced with Bcl-2 overexpression. We then demonstrated that the E1B-55K protein of human adenovirus type 5 (Ad5), which was known to bind and repress p53 transcriptional activity, blocks cell death following p53 expression. These results directly show that E1B-55K is able to inhibit p53-induced apoptosis. This ability is important for adenovirus replication because alone, the 289-residue (289R) and 243R E1A products of Ad5 induce p53-dependent apoptosis which would inhibit progeny production. / During the course of this work, we also found that the 289R E1A protein is able to induce p53-independent apoptosis, and the remainder of this thesis work is focused on that question. Preliminary results suggested that p53-independent cell death required expression of additional Ad5 early gene products. We found that E1B-19kDa and Bcl-2 inhibited this p53-independent killing. Neither early regions E2 or E3 were necessary for cell death, but analysis of a series of E1A mutants indicated that mutations disrupting transactivation of E4 gene expression abolished killing. Furthermore, Saos-2 cells infected with an E1B +/E4- viral mutant remained viable for considerably longer times than those infected with wt Ad5. In addition, an E1-/E4- adenovirus vector was unable to induce cell killing in E1A-expressing cell lines, indicating that an E4 product is essential for E1A-induced p53-independent apoptosis. / To identify which E4 products are involved, studies were conducted in p53-deficient human Saos-2 cells infected with various Ad5 E4 mutants. An E4orf6-deficient mutant was defective in cell killing whereas another which expressed only E4orf6 and E4orf4 killed like wt virus, suggesting that E4orf6 may be responsible for cytotoxicity; however, a mutant expressing only E4orf4 induced high levels of cell death, indicating that this E4 product may also be cytotoxic. To define the E4 cell death-inducing functions more precisely, cDNAs encoding individual E4 products were introduced into cells by DNA transfection together with a cDNA encoding firefly luciferase. Enzymatic activity was high in all cases except with E4orf4 where levels were less than 20% of controls. In addition, drug selection of cells following transfection with a puromycin-containing retroviral vector encoding individual E4 products yielded a high number of cell colonies except when E4orf4 was expressed. These data demonstrated that E4orf4 is the only E4 product capable of independent cell killing. Death was due to apoptosis, as evidenced by the morphology of DAPI stained cell nuclei. This identification of a p53-independent apoptosis pathway has offered considerable insight into how the virus may ultimately be killing the host cell. Additionally, it has directed us to another cellular apoptosis pathway which will contribute to our understanding of the life and death balance in the cell.

Background. The early diagnosis and treatment of breast cancer has become an important health care concern. A recent study reported the median waiting time for breast cancer surgery in Quebec was 34 days with 14% of women waiting in excess of 90 days. Understanding the determinants of long waiting is essential to develop optimum interventions to reduce delay. Objective. The purpose of this study was to identify the determinants of waiting time to surgery among women with primary breast cancer in Quebec between 1992 and 1997. Methods. The target population was all women 20 years and older diagnosed with primary breast cancer in Quebec between 1992 and 1997. The data was compiled from physician fee-for-service claims maintained by the Regie de I'assurance maladie du Quebec (RAMQ); the Quebec hospital discharge database (MedEcho), and the 1991 Canadian census. Waiting time was defined as the number of days from the initial breast diagnostic procedure to the first definitive surgical treatment. Three-level hierarchical linear models were used for statistical analysis. Findings . Overall, 13,383 women with primary breast cancer treated by 614 surgeons in 107 hospitals were identified. No statistically significant variation of waiting time was found among hospitals. Longer waiting times for breast cancer surgery were observed for women 50 to 64 years of age, without comorbidity, with history of benign breast disease, living in the lower education areas, having surgery at day-surgery setting, having surgery in more recent years, or having surgery performed by younger a surgeon (20 to 49 years old). Women who had surgery performed in a teaching hospital had longer waiting times and this effect was larger when mastectomy was performed. These results could be used to identify women and care delivery practices at higher risk for delays which could be the focus of interventions.

This thesis comprises three independent but interrelated manuscripts. (1) The results from seven epidemiological studies of adult cancers in relation to residential exposure to power frequency magnetic fields (MF) indicated that the association between leukemia and MF has been inconsistent. It also indicated that the risks of brain tumors and breast cancer, the other cancers frequently suspected of being associated with occupational exposure to MF, were rarely investigated. Based on these epidemiological results, the analysis of the roles of chance and bias, and the criteria for causal inferences, it appears that the evidence is not strong enough to support the putative causal relationship between residential MF and adult cancers. (2) A case-control study, using matching on date of birth, sex, and date of diagnosis, was therefore carried out in northern Taiwan to further evaluate the risks of adult ($ sbsp{=}{>}$ 15 years of age) leukemia, brain tumors, and female breast cancers in relation to residential exposure to 60 Hz MF. Cases were newly diagnosed cancers reported to the cancer registry between 1987 and 1992 and controls were incident cancers from sites other than those previously suspected of being associated with MF during the same period. Assessment of MF in the residences occupied by the study subjects at the time of diagnosis was performed by modeling power information of high-voltage transmission lines. The results were based on the separate analysis of 708 leukemia, 455 brain tumors, and 1,562 female breast cancers. The risk of leukemia for exposure to MF $>$ 0.2 $ mu$T relative to the reference level ($<$0.1 $ mu$T) was significantly elevated (odds ratio = 1.51, 95% confidence interval 1.05-2.19). A dose-response relationship showed a gradient increase in relative risk estimates for leukemia with MF. The relative risk estimates for brain tumors and female breast cancers were slightly elevated, but were statistically compatible to null. (3) To valida

The importance of developing relevant ovarian cancer models led us to test the applicability of a system comprised of epithelial ovarian cancer cell lines. The high frequency of loss of heterozygosity (LOH) and rearrangements of chromosome 17 in ovarian tumors provide evidence of a role of chromosome 17 genes in ovarian tumorigenesis. Oligonucleotide microarray expression analysis was applied to assess the expression profiles of 864 probe sets that map to chromosome 17. The TOV112D ovarian cancer cell line, a spontaneously immortalized and tumorigenic ovarian cancer cell line derived from an endometrioid histopathological subtype, which has been shown to exhibit LOH of chromosome 17, was used as a model to identify candidate genes based on Affymetrix expression microarray analyses in comparative analysis with three primary cultures derived from normal ovarian surface epithelium (NOSE). Two-way comparative analyses identified 81 probe sets, representing 64 differentially expressed genes, which exhibited at least a three-fold difference in expression relative to the mean of NOSE samples. The expression of these 64 candidate genes was investigated by microarray analysis in 31 fresh solid malignant ovarian tumors of different histopathologies, six ovarian tumors of borderline pathology, 32 primary cultures of ovarian tumors, 28 primary cultures of malignant ovarian ascites, and 16 NOSE samples. The chromosome 17 expression profile of TOV112D monolayer was compared with this cell line grown as a three-dimensional spheroid, solid tumors and monolayer cultures of these tumors from intraperitoneal and subcutaneous injection into nude mice. The expression profiles of selected candidates were validated by RT-PCR. About 63% of the candidates overexpressed at least three-fold relative to TOV112D were also overexpressed in some of the solid malignant ovarian tumors, and about 91% of the candidates that were underexpressed at least three-fold in TOV112D were also underexpressed in some of these tumors. The same differential pattern of gene expression of candidates was also observed in primary cultures of ovarian tumors and ovarian ascites, however, the effect in primary cultures was reduced. These results indicate that TOV112D, representing a spontaneously immortalized long-term passage, was more representative of solid ovarian tumors compared with the primary cultures. Growth conditions showed little impact on the expression profile of candidates when TOV112D was grown in different culture environments such as in vitro monolayer or mouse tumor xenograft. The finding that TOV112D identified differentially expressed genes in ovarian tumor samples regardless of histopathological subtype indicates that it is a useful model, not only to study the endometrioid subtype, but also serous and clear cell subtypes of epithelial ovarian cancer. Comparison of the expression profiles of our candidate genes identified by microarray analysis with published reports revealed that eight genes (ACACA, SFRS2, CCL2, CSF3, IGFBP4, KRT19, ITGA3, and TIMP2) were previously implicated in ovarian cancer, and 23 including MAC30 and TBX2 were implicated in tumorigenesis of other types of cancers. The use of long-term ovarian cancer cultures provides scientists with a model to study candidate genes, some of which may prove important for early detection or represent targets for the development of new ovarian cancer treatments.