Clinical information was collected from 283 randomly chosen ovarian cancer cases from at the Saskatoon Cancer Centre between the years 1983-1995. The data was evaluated for its significance in predicting survival and relapse free survival (RFS) using univariate and multivariate analysis. Several clinical prognostic factors were identified by univariate analysis. Additionally, using Cox's regression model the independent markers of survival and RFS were FIGO stage, and residual disease in 173 and 178 patients respectively. Data on CA 125 serum level, (available in 89 patients) was a marker of prognostic significance in the patients treated with platinum based chemotherapy. CA 125 and CEA antigen expression were also evaluated in seventy one cases. It was found that mucinous neoplasms exclusively expressed CEA antigen. This study indicates that the evaluation of serum level CEA may be a complementary tool for patients with cancers not expressing CA 125. In this retrospective study, DNA from paraffin embedded tissue (PET) in patients with ovarian carcinoma was examined to identify gene abnormalities in p53, p16INK4A, RB-1, p21WAF1/CIP1, Cyclin D1, Erb-B2, and MSH2. Adverse outcome was also examined in addition to survival and RFS, to identify novel molecular prognostic markers. P53 overexpression in 44 of 112 (39%) was associated with reduced survival and RFS (' p' = '0.04' and 'p' = '0.008 '). Aneuploid DNA content, found in 34 of 112 (30%) cases, was associated with shorter survival and RFS ('p' = '0.03' and 'p' = '0.01'). Dot blot hybridization of G1-S control genes (p16INK4A, Cyclin D1, RB-1, and CDK4) did not identify amplification or deletion events to be associated with adverse outcome. A number of gene alterations in 59 of 63 (94%) ovarian cancer cases were detected by dot blot hybridization; the lack of association with clinical outcome indicated that there may be some other genes in addition to those examined that are of prognostic significance. For eighteen cases, microsatellite instability (MSI) was evaluated by using fluorescently labeled primers at nine loci. LOH was a common event in ovarian carcinoma but MSI was infrequent. Molecular and clinical marker multivariate analysis indicated: (a) residual disease for survival, (b) stage and residual disease for RFS, were independent markers of prognosis.

No description available.

Since high-risk Human Papillomavirus (HPV) plays a critical role in cervical carcinogenesis, it is essential to improve our understandings on the role of HPV-related molecular markers in cervical neoplasia. The aim of this study was to investigate the expression and prognostic significance of selected HPV-related markers, including HPV16/18 E2 binding sites (E2BS) methylation, Pak 1, c-FLIP, Notch 1 and Brd4 expressions, as well as the potential functions of Pak 1 in cervical neoplasia. First, the differential expressions of these markers among clinical samples of normal cervical epithelium, low-grade and high-grade cervical intraepithelial neoplasia (CINs) and cervical cancer were studied. Methylation status of E2BS 1, 2 and 4 was determined by pyrosequencing. Expressions of the target proteins were assessed by immunohistochemistry. Both HPV16/18 E2BS 1&2 and E2BS4 methylation progressively increased from normal cervix through CINs to cancer. More importantly, HPV16 E2BS1&2 (for transcriptional repression of E6/E7 oncoproteins) became more heavily methylated than E2BS4 (for transcriptional activation of E6/E7) in cervical cancer, favouring the differential binding of E2 protein to E2BS4. Pak 1, c-FLIP, Notch 1 and Brd4 were all overexpressed in cervical cancer. Their expressions increased progressively from normal cervix to low-grade +/- high-grade CINs. Pak 1 and c-FLIP expression was positively correlated with HPV18 E6 and HPV16 E7 expression respectively. Notch 1 expression was inversely correlated with HPV16 E7 and HPV18 E6 expressions. Brd4 expression was positively correlated with HPV16 E2 and inversely correlated with HPV16 E7 expressions. The prognostic significance of the molecular markers was investigated by correlation with clinical parameters. Heavier methylation at E2BS1&2 relative to E2BS4 was associated with better overall and disease-free survival in cervical cancer patients. HPV16 E2BS1&2 hypermethylation, weak cytoplasmic Brd4 expression, strong c-FLIP or Notch 1 expression were associated with higher risk of recurrent abnormal smears after treatment of CINs. The role of Pak 1 in cervical cancer was further explored by comparing its functions between cervical cancer cell lines with and without transient knock-down of Pak 1 by siRNAs. It was demonstrated that the significant functions of Pak 1 in cervical cancer were on promoting cell proliferation and inhibiting apoptosis. Transient HPV16 E6 inhibition showed no effect on total / phosphorylated Pak 1 expressions. Lastly, the function of Pak 1 on the regulation of cervical cancer cell radiosensitivity was also investigated. Pak 1 inhibition increased cell sensitivity in response to irradiation by enhancing apoptosis and inhibiting cell proliferation. Conclusively, differential methylation status at HPV16/18 E2BS, as well as Pak 1, c-FLIP, Notch 1 and Brd4 proteins contribute to cervical carcinogenesis, and are potential prognostic markers in cervical cancer and CIN patients. Pak 1 inhibitor may be a potential adjunctive agent to improve radiotherapy. / published_or_final_version / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy

published_or_final_version / abstract / Surgery / Doctoral / Doctor of Philosophy

published_or_final_version / Surgery / Master / Master of Philosophy

published_or_final_version / Surgery / Doctoral / Doctor of Philosophy

published_or_final_version / Medicine / Master / Doctor of Medicine

Abstract In tumourigenesis, genetic alterations accumulate in the genes responsible for cell growth, proliferation and DNA repair: proto-oncogenes, tumour suppressor and DNA repair genes. Inactivation of tumour suppressor gene function is commonly recognised as a deletion of one of the two alleles; LOH, loss of heterozygosity. In the present study, LOH of several chromosomal regions was studied in both breast and ovarian cancer. LOH for chromosome region 11q was examined in a large breast cancer consortium cohort (N = 988) and in a Finnish ovarian cancer cohort (N = 78), and the clinical significance of these alterations was evaluated. In breast cancer, LOH of the studied markers at 11q23.1, harbouring approximately 2 Mb of DNA, was seen to be associated with shortened cancer-specific survival. Two candidate genes, ATM (the ataxia telangiectasia disorder gene) and DDX10 (a putative RNA helicase gene) map to this chromosomal region. In ovarian cancer, LOH at 11q23.1–q24 was assigned mainly to two chromosomal regions, A and B, which are proximal and distal to 11q23.2–q23.3, respectively. Only the distal B region was seen to be associated with an aggressive disease course. Therefore, it appears that inactivation of the ATM or DDX10 genes is not crucial for determining the outcome of ovarian cancer. The CHK1 gene at 11q24, encoding a protein kinase required for DNA damage checkpoint function, is a putative target gene at the B region. On the basis of the present results, the main TSG in the studied region involved in the progression of breast cancer maps to 11q23.1 and the corresponding gene for ovarian cancer more distally to 11q23.3-q24. In addition, LOH at 3p, 6q, 8p, 11p, 16q and 17p was examined and their role in the genetic evolution of ovarian cancer was evaluated. Of the studied chromosomal regions, LOH at 17p appeared to be an early event and LOH at 16q24.3, 11q23.3/q24 and 11p appear to occur later in the progression of ovarian cancer.

Prognostic indicators, measured at diagnosis, are important in breast cancer. They help clinicians select optimal treatment, provide rational bases for stratification of treatment trials and assist analysis of response to treatment. Univariate statistical survival curves have identified many such indicators. However, they do not explain why some patients, classified as favoured by one or other factor(s), experience early treatment failure, nor why a substantial number with unfavourable signs remain recurrence-free many years later. This study was undertaken to identify independent prognostic factors with the use of multivariate regression. A Cox proportional hazards model of disease-specific survival was based on 1184 primary breast cancer patients referred to the Cancer Control Agency of B.C. between 1975 and 1981 (median follow-up 60 months). Significant univariate associations with overall survival were found for estrogen receptor concentration ([ER]), axillary nodal status (NO, Nl-3, N4+), clinical stage (TNM I, II, III, IV), histologic differentiation and confluent tumor necrosis (minimal, marked). These factors were assessed at primary diagnosis. A subset of 859 patients with complete data on these variables and also histologic type, menopausal status, age, tumor size and treatment was used to fit the multivariate model. Nodal status was the most important independent factor but three others, TNM stage, [ER] and tumor necrosis, were needed to make adequate predictions. A derived Hazard Index defined risk groups with 8-fold variation in survival. Five-year predicted survival ranged from 36% (N4+, loge[ER]=0, marked necrosis) to 96% (NO, loge[ER]=6, no necrosis) with TNM I and 0% to 70% for the same categories in TNM IV. This wide variation occurred across all stages. Study of post-recurrence survival (369 patients) yielded a model with only three independent predictors: [ER], nodal status and tumor necrosis. Survival - overall, recurrence-free and post-recurrent - is predictable by modelling a few factors measureable at diagnosis. Use of ER concentration, rather than the more common ER status (+ or -), greatly strengthens the model. Presence of ER was also shown to be increasingly important as 'protective', attenuating the effect of other factors, as risk of mortality increases. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate

published_or_final_version / abstract / Surgery / Master / Master of Surgery