Background: The aim of this thesis was to study the relationship of pre-diagnostic circulating concentrations of sex steroid hormones (androgens, estradiol, 17-hydroxyprogesterone, and progesterone), growth factors (insulin-like growth factor-I (IGF-I), placental growth hormone (GH)), sex hormone binding globulin (SHBG), and anti-Müllerian hormone (AMH) with risk of epithelial ovarian cancer (EOC) overall, and by tumor invasiveness and histology. A longitudinal study was used to assess patterns of hormonal changes during a single pregnancy, and in two consecutive pregnancies. Materials & Methods: A case-control study was nested within the Finnish Maternity Cohort and the Northern Sweden Maternity Cohort. A total of 1 052 EOC cases were identified through linkages with the cancer registries in both countries. For each case, 2-3 controls were selected. Cases and controls were matched on cohort, age and date at blood draw, as well as for parity at blood draw and at diagnosis (n=2 695). Odds ratios (OR) and corresponding 95% confidence intervals [CI] were estimated using conditional logistic regression. The longitudinal study was based on 71 pregnant Finnish women, who donated blood samples in each trimester of pregnancy. Results: Higher androgen concentrations were associated with an increased risk of overall EOC (e.g., testosterone ORT3 vs. T1: 1.56 [1.30-1.87], ptrend<0.0001), while the risk of endometrioid tumors increased with higher estradiol concentrations (ORT3 vs. T1: 2.76 [1.04-7.33], ptrend=0.03). Higher IGF-I was associated with a non-significant decrease in risk for invasive (ORT3 vs. T1: 0.79 [0.62-1.02], ptrend=0.07) and endometrioid tumors (ORT3 vs. T1: 0.55 [0.28-1.07], ptrend=0.07). The inverse association between IGF-I levels and risk of invasive EOC was stronger in analyses limited to women aged <55 years at diagnosis (ORT3 vs. T1: 0.74 [0.57-0.96], ptrend=0.03). No associations were observed between pre-diagnostic progesterone, SHBG, placental GH, and AMH with EOC risk overall, or by tumor invasiveness and histology. The longitudinal study showed that hormone concentrations were more strongly correlated between consecutive trimesters of a pregnancy than between the 1st and 3rd trimesters. Further, 3rd trimester hormone concentrations can be estimated from 1st or 2nd trimester measurements. Conclusion: Higher pre-diagnostic androgens, estradiol, and IGF-I are associated with EOC risk, and associations differ by tumor invasiveness and histology.

Ovarian cancer is a significant concern for women’s health as it is the most lethal of all gynaecological malignancies. One of the reasons for the high mortality of this disease is that traditionally used chemotherapeutic treatments tend to have poor initial or sustained efficacy against ovarian tumours. Resistance to such treatments may in part be mediated by autophagy, a cell survival process in which unnecessary or damaged components of the cytoplasm are engulfed within a double-membraned vesicle known as an autophagosome and ultimately degraded upon fusion of the autophagosome with a lysosome. Autophagy has been shown to be employed by cells to aid in their survival under stresses such as nutrient deprivation, hypoxia, chemotherapy treatment, and growth factor withdrawal. As these stresses are commonly encountered by ovarian cancer cells, it is possible that autophagy promotes ovarian cancer cell survival. This thesis aims to investigate which stimuli induce autophagy in ovarian cancer cells and whether or not this induction can promote cell survival. In addition, there is a particular focus on the comparison of autophagy utilization between subtypes of ovarian cancer, as the subtypes are in fact considered different diseases and may vary in their usage of autophagy. The first chapter of this thesis provides relevant background information on autophagy as well as ovarian cancer and its subtypes. In the second chapter, I describe studies in which tumours from a large cohort of patients with ovarian cancer are assessed for LC3A, a marker of autophagy, in addition to markers of other cellular processes including hypoxia. Here I found that LC3A was significantly associated with poor patient survival in patients with the clear cell subtype of ovarian cancer, but not other subtypes. I also found that LC3A expression was associated with markers of hypoxia in the clear cell patient tumours and that clear cell carcinoma cell lines preferentially induced autophagy in response to hypoxia in vitro as compared to cell lines of the high-grade serous subtype. These results indicate that clear cell ovarian tumours are uniquely dependent upon autophagy in response to hypoxia. In the third chapter, I investigated the autophagic response to treatment with the standard ovarian cancer chemotherapy drugs carboplatin and paclitaxel in a syngeneic mouse model of ovarian cancer. I found that these drugs did indeed induce autophagy and that the cancer cells utilized autophagy to promote resistance to these chemotherapeutics. In addition, when the tumour cells were grown in syngeneic mice, treatment with the autophagy inhibitor hydroxychloroquine resulted in a significant suppression of tumour growth. Together, my findings indicate that further investigation into the use of autophagy inhibitors in ovarian cancer patients is warranted and that different specific rational drug combinations for each subtype will likely yield optimal results. / Graduate

Ovarian cancer, with the highest mortality rate amongst gynaecological malignancies in Australia, is the eighth most common cancer and the fifth cause of cancer-related deaths in women. Currently, five-year survival for women diagnosed with ovarian cancer is only 40 % and despite many patients experiencing remission, approximately 80 % of them will relapse due to residual micrometastasis. The limited impact of standard therapies on the prognosis for recurrent chemotherapy-resistant disease and the need to identify less toxic alternatives has motivated the development of strategies to combat the aggressive and life-threatening burden of ovarian cancer. A novel therapy against cancer utilises dendritic cells (DC), potent antigen presenting cells, to deliver tumour antigens to the immune system for the stimulation of cytotoxic T-lymphocyte (CTL) responses. DC immunotherapy has been used for the treatment of patients with ovarian cancer; however, clinical responses after the injection of antigen-loaded DC have been disappointing. Therefore, the identification of additional tumour associated antigens (TAA) is required. A TAA highly expressed in ovarian cancer cells, CA125, is a candidate target for DC-based immunotherapy. Initially, CTL responses to CA125 were studied in the context of HLA-A*0201. CD8+ T-cell responses specific for CA125 peptides (with high affinity for the MHC class I) were generated from cultures initiated with peptide-loaded monocyte-derived DC (Mo-DC). To expand the evaluation of T-cell recognition of CA125 to non-HLA-A*0201 individuals, messenger RNA (mRNA) was investigated as an antigen-loading vehicle. RNA encodes for the repertoire of epitopes presented by the TAA, potentially inducing immune responses in the context of multiple MHC class I and II molecules to known/unknown antigens. One focus of this study was to investigate a novel mRNA transfection system utilising mannan for the delivery of mRNA into DC. Initially the immunomodulating effect of mannan was examined in terms of DC activation. Mannan induced the phenotypic and functional maturation of immature Mo-DC in vitro. Next, the ability of oxidised mannan (OxM) linked to mRNA was investigated for its capacity to deliver enhanced green fluorescent protein (EGFP) mRNA into DC. We observed high transfection efficiencies in the murine and in human DC systems using low mRNA concentrations, in the absence of significant cell viability impairment. Interestingly, upon mRNA delivery via the OxM-PEI complex, DC maturation was induced to considerably higher levels as compared with that achieved with electroporation and non-transfected controls, this was measured by phenotype (CD83) and IL-12 secretion. Within this study, OxM-PEI did not deliver TAA encoding mRNA into DC for the stimulation of CTL. In summary, mannan is a novel strategy to deliver mRNA and a strong maturation signal simultaneously to human Mo-DC. The functional capacity of this system requires further investigation before it can be considered for clinical use. Electroporation has evolved as a superior method for mRNA delivery into DC as reported in the literature. Therefore, a comprehensive study was performed encompassing the critical issues associated with transfection efficiency, in order to standardise an electroporation protocol for use in DC immunotherapy schedules. EGFP was used as a model antigen to optimise mRNA uptake by Mo-DC by monitoring the expression of the reporter gene by FACS analysis. Influenza matrix protein 1 mRNA was, then, utilised as a model antigen for MHC class I restricted antigen presentation, for confirmation of the optimised loading parameters. The efficiency of this delivery system was assessed using CA125 mRNA in stimulating antigen-specific T-cell responses in PBMC of healthy individuals. CD4+ and CD8+ antigen-specific T-cell responses were generated recognising CA125 mRNA loaded Mo-DC and also ovarian cancer cell lines endogenously expressing CA125. This study has identified CA125 specific T-cell responses in healthy donors, allowing further investigation into the potential for its use as a candidate TAA in ovarian cancer immunotherapy. Furthermore, the use of Mo-DC transfected with mRNA encoding TAA is a promising strategy for the delivery of TAA in the generation of antigen-specific T-cell responses. In summary, the results gained from this PhD thesis should be taken into consideration when designing future DC immunotherapy strategies to combat one of the leading causes of cancer mortality in women, ovarian cancer.

Submitted by ALINE EVANGELISTA SANTIAGO null (evalineva@hotmail.com) on 2017-12-19T17:39:39Z No. of bitstreams: 1 DISSERTAÇÃO PDF (1).pdf: 6165905 bytes, checksum: 0fe2e6627556b7a80341cb2a27e96540 (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2017-12-20T13:25:02Z (GMT) No. of bitstreams: 1 santiago_ae_me_bot.pdf: 6165905 bytes, checksum: 0fe2e6627556b7a80341cb2a27e96540 (MD5) / Made available in DSpace on 2017-12-20T13:25:02Z (GMT). No. of bitstreams: 1 santiago_ae_me_bot.pdf: 6165905 bytes, checksum: 0fe2e6627556b7a80341cb2a27e96540 (MD5) Previous issue date: 2017-11-24 / Introdução: A concentração plasmática de citocinas, quimiocinas e micropartículas (MPs) em mulheres com câncer de mama e de ovário é uma forma não invasiva de avaliar a resposta inflamatória/regulatória sistêmica associada a esses tumores e o papel do microambiente formado na resposta pró e antitumoral na paciente. Portanto, o objetivo deste estudo foi comparar o perfil da resposta inflamatória sistêmica do câncer epitelial de ovário (CEO) e do câncer de mama através da medição de citocinas, quimiocinas e MPs, para assim avaliar se existe ou não diferença nesse padrão de resposta inflamatória sistêmica. Métodos: Noventa e quatro mulheres sem evidência de malignidade (n = 30), com câncer de mama (n = 38) ou câncer de ovário epitelial (n = 26) foram avaliadas. Foram coletadas amostras plasmáticas e de tecido tumoral. A avaliação dos marcadores inflamatórios foi realizada pela dosagem de citocinas (IL-1, IL-2, IL-6, IL-10, IL-12, IL-17A, TNF-α e IFN- ), quimiocinas (CXCL8, CXCL -9, CXCL 10, CCL 2, CCL5) e MPs (neutrófilos, leucócitos, monócitos, eritrócitos, células endoteliais, plaquetas e linfócitos) por citometria de fluxo / Cytometric Bead Array. As diferenças entre os grupos foram avaliadas por Kruskal-Wallis. As diferenças com p<0,05 foram consideradas significantes. Resultados: Os níveis plasmáticos das citocinas pró-inflamatórias IL-6 (p=<0,001), TNF-α (p=0,004) e IL-12 (p=0,0019) foram significativamente maiores em pacientes com câncer de ovário em comparação com as mulheres com câncer de mama e com o grupo controle. Pacientes com câncer de ovário foram também associadas a maiores níveis de IL-10 (p<0,001) e das quimiocinas CXCL-9 (p<0,001) e CXCL-10 (p<0,001) em comparação aos outros grupos. Os níveis de MPs derivados de neutrófilos aumentaram significativamente em amostras plasmáticas de pacientes com CEO em comparação com mulheres com câncer de mama e do grupo controle (p<0,001). Em contraste, as MPs derivadas de células endoteliais foram menores nas pacientes com CEO em comparação com os demais grupos (p=0,0491). Houve um equilíbrio entre citocinas, quimiocinas e MPs nos grupos de câncer de mama e controle. A rede de citocinas e quimiocinas inflamatórias/regulatórias em pacientes com CEO apresentou maior complexidade em relação aos demais grupos e com fortes interações nas redes entre fatores inflamatórios e imunológicos plasmáticos. Esta rede incluiu mais biomarcadores associados com correlações negativas e positivas entre eles. Conclusão: Este estudo é uma pesquisa promissora e original. Os resultados podem refletir as discrepâncias entre a carcinogênese no câncer de ovário e de mama, sugerindo um padrão inflamatório sistêmico maior no CEO. MPs podem servir como uma nova fonte de informação relacionada à doença. / Introduction: The plasma concentration of cytokines, chemokines and microparticles (MPs) in women with breast and ovarian cancer is a noninvasive way of assessing the systemic inflammatory / regulatory response associated with these tumors and the role of the microenvironment formed in the pro and antitumor response in the patient. Therefore, the objective of this study was to compare the profile of the systemic inflammatory response of epithelial ovarian cancer (EOC) and breast cancer by measuring cytokines, chemokines and MPs, in order to evaluate whether or not there is a difference in this pattern of inflammatory response systemic. Methods: Ninety-four women with no evidence of malignancy (n = 30), breast cancer (n = 38) or epithelial ovarian cancer (n = 26) were evaluated. Plasma samples and tumor tissue were collected. The evaluation of inflammatory markers was performed by the measurement of cytokines (IL-1, IL-2, IL-6, IL-10, IL-12, IL-17A, TNF-α and IFN-), chemokines (CXCL8, CXCL -9, CXCL 10, CCL 2, CCL 5) and MPs (neutrophils, leukocytes, monocytes, erythrocytes, endothelial cells, platelets and lymphocytes) by flow cytometry / Cytometric Bead Array. The differences between the groups were assessed by Kruskal-Wallis. Differences with p <0.05 were considered significant. Results: Plasma levels of the proinflammatory cytokines IL-6 (p = 0.001), TNF-α (p = 0.004) and IL-12 (p = 0.0019) were significantly higher in ovarian cancer patients compared to women with breast cancer and the control group. Patients with ovarian cancer were also associated with higher levels of IL-10 (p <0.001) and CXCL-9 (p <0.001) and CXCL-10 (p <0.001) chemokines compared to the other groups. Levels of MPs derived from neutrophils increased significantly in plasma samples of EOC patients compared to women with breast cancer and the control group (p <0.001). In contrast, MPs derived from endothelial cells were lower in patients with EOC compared to the other groups (p = 0.0491). There was a balance between cytokines, chemokines and MPs in the breast cancer and control groups. The network of inflammatory / regulatory cytokines and chemokines in patients with EOC presented greater complexity in relation to the other groups and with strong interactions in the networks between inflammatory and immunological plasmatic factors. This network included more biomarkers associated with negative and positive correlations between them. Conclusion: This study is a promising and original research. The results may reflect the discrepancies between carcinogenesis in ovarian and breast cancer, suggesting a higher systemic inflammatory pattern in the EOC. MPs can serve as a new source of disease-related information.

Hereditary non-polyposis colon cancer syndrome (HNPCC) is associated with an increased risk of developing several types of cancer and is the most common cause of hereditary ovarian cancer after BRCA1 and BRCA2 mutations. HNPCC results from a germline mutation in one of the DNA mismatch repair (MMR) genes: MLH1, MSH2, PMS1, PMS2, MSH6, MSH3 and MLH3. While there has been extensive investigation of MMR deficiency in colorectal cancer, MMR in ovarian cancer is relatively under-investigated. The goal of this project was to study MMR deficiency in ovarian cancer at both the clinical and molecular level. The first aim was to examine the frequency of MMR loss in a large patient cohort and investigate the clinical consequences of MMR deficiency. The second aim was to describe the molecular characteristics of MMR deficiency in ovarian cancer cell lines and establish an in vitro cell line model of MMR deficiency in ovarian cancer. The third aim was to identify synthetic lethal strategies for the treatment of ovarian cancer to maximise cytotoxicity in a MMR-deficient background. In order to characterise the clinical consequences of MMR deficiency, a large patient cohort was studied with regard to MMR status. Three tissue microarrays consisting of 581 ovarian tumours were constructed, and expression of the four most frequently lost MMR proteins: MLH1, MSH2, PMS2 and MSH6 were detected by immunohistochemistry. Afterwards, MMR status and histology subtypes were analysed in combination with the associated clinical data. The overall incidence of MMR deficiency (loss of any MMR protein) was 15.7%, with PMS2 being the most frequently lost protein (9.7%). In addition, MMR deficiency tended to appear in a grouped fashion: MLH1 with PMS2; MSH2 with MSH6. Patients with non-serous subtypes of ovarian cancer, clear cell or mucinous especially, had higher incidence of MMR deficiency compared to patients with serous ovarian cancer. Overall MMR deficient patients were more likely to be diagnosed at early stages compared with MMR proficient patients, and this is probably due to the association between MMR deficiency and non-serous histology. However, platinum-based treatment for patients with MMR deficiency gives no advantage over those without MMR deficiency. Therefore better treatments for this subgroup of patients may be needed. The features of MMR deficiency in ovarian cancer were also characterized at the molecular level. After quantifying mRNA and protein expression of MMR genes in 19 ovarian cell lines, three cell lines (SKOV3, TOV21G and IGROV1) were found to have a defect in MLH1 expression at both the mRNA and protein level. Interestingly, the three cell lines also carried a defect in PMS2 expression at the protein level but not at the mRNA level, which is consistent with our clinical data demonstrating that MLH1 protein and PMS2 protein are paired in loss. In addition, across the 19 cell lines, MLH1 and PMS2 showed positive correlation at both the mRNA level (R=0.53, p=0.02) and protein level (R=0.72, p=0.0006). In order to study co-expression of MLH1 and PMS2, a plasmid encoding the cDNA for MLH1 was transfected into the three MLH1 deficient cell lines; and conversely siRNA targeting MLH1 was transfected into the MMR proficient cell line A2780 and expression of MLH1 protein and PMS2 protein was quantified. The results showed that re-introduction of MLH1 into MLH1 deficient cells resulted in increased expression of PMS2 protein, while knocking down MLH1 in MMR proficient cells leads to decreased PMS2 protein expression. This indicates that MLH1 may play a crucial role in regulating PMS2 protein expression. As the three MLH1 and PMS2 protein deficient cell lines all express PMS2 mRNA, the regulation of PMS2 expression by MLH1 is likely to be at the translational or post-translational level. However, the expression of PMS2 protein was not increased in the absence of MLH1, even when the proteasomal and lysosomal protein degradation pathways were blocked (as seen with SKOV3 cells), suggesting decreased PMS2 protein expression is not due to rapid degradation in the absence of MLH1. Therefore MLH1 may play a role in regulating the synthesis of PMS2 protein at the translational level, rather than preventing the degradation of PMS2. Thus, to investigate the mechanism by which PMS2 protein levels are regulated by MLH1, future work should focus on translational regulation of PMS2. In order to identify synthetic lethal strategies to target MMR deficiency in ovarian cancer, an isogenic cell line model of MMR deficiency was established by stable transfection of a plasmid for MLH1 and its corresponding empty vector into SKOV3 cells. The MLH1+ cell line SAC-1 and MLH1- cell line SN-5 were selected for drug screening based on their phenotype and growth rate. The AlamarBlue assay, with z’ above 0.5, was chosen for drug screening and a kinase inhibitor library containing 362 drugs of known target was screened. Two drugs with similar structures that targeted PLK1 showed greater growth inhibition of SN-5 compared with SAC-1. When the two cell lines were treated with another PLK1 inhibitor, BI2536, with different structure, a 2-fold difference in growth inhibition between SAC-1 and SN-5 was also observed, suggesting PLK1 is a potential synthetic lethal target for MLH1 deficiency in ovarian cancer. Together these data demonstrate that clinically, MMR deficiency is associated with non-serous subtypes of ovarian cancer and specific MMR proteins are paired in loss. While current standard therapy offers no selective benefit to ovarian cancer patients with MMR deficiency, inhibiting PLK1 activity may confer selective benefit.

Structured abstract Study objectives: Ovarian carcinoma 1/ comparison of sensitivities among monitored markers CA 125, HE4, CA 19-9, CEA, TK, TPS, MonoTotal 2/ comparison of false positivity of markers CA 125 and HE4 3/ use of CA 125, HE4 and ROMA index in the diagnostics of ovarian carcinoma 4/ use of CA 125 and HE4 in the follow-up of ovarian cancer Endometrial carcinoma 1/ feasibility of use of biomarkers CA125 and HE4 in patients with endometrial cancer in pre- operative management Study design: Retrospective data analysis Settings: Department of Obstetrics and Gynecology, Medical Faculty and Teaching Hospital in Pilsen Patients and Methods: Ovarian cancer 1/ Sensitivity of markers CA 125, HE4, CA 19-9, CEA, TK, TPS, and MonoTotal was assessed in 266 patients - 19 with ovarian cancer and 247 with benign disorders. 2/ False positivity of markers CA125 and HE4 was evaluated in a total of 390 patients with benign diagnoses - 60 women with endometriosis, 70 pregnant patients, 67 patients with ascites, 60 with pleural effusion, 25 with cardiac failure , 80 with renal insufficiency and 28 with hepatic failure. 3/ As a part of this objective we evaluated 552 patients with abnormal pelvic abnormality - 30 women had a histologically confirmed malignant ovarian tumor. Other 522 women had a benign condition. The...

Structured abstract Hypothesis Cancer stem cells (CSCs) are subpopulations of cells which could contribute to tumor growth, metastasis formation and chemoresistance. CSCs can be detected by surface markers assessed by immunohistochemistry methods. A typical surface marker for CSCs is CD44 (standard form). We assumed, that CD44(s) could serve as a prognostic factor and marker of chemoresistance in patients with epithelial ovarian cancer. The aim of study 1. To recruit group of patients with histologically verified epithelial ovarian carcinoma. 2. To evaluate prognostic significance of known prognostic factors in our series of patients. 3. To assess the expression of CD44 in specimens of primary tumors and specimens of implantation metastasis using immnunohistochemistry and analyze their correlation. 4. To evaluate the expression of CD44 in relation to known prognostic factors. To analyze the significance of CD44 expression evaluation for overall survival, disease-free interval and chemoresistance. To find CD44 positivity cut-off by using statistical methods Materials and Methods A retrospective study was performed on 87 patients with histologically verified EOC. All patients were tested for primary tumor specimens, 48 of them were tested with regard to both specimens of primary tumor and implantation...

Acute myeloid leukaemia (AML) and ovarian cancer (OVC) are two difficult to treat cancers. AML is often treatable however minimal residual disease (MRD) endures such that many patients who achieve remission eventually relapse and succumb to the disease. OVC affects approximately 7000 women in the U.K. every year. It can occur at any age but is most common after menopause. Diagnosis at an early stage of disease greatly improves the chances of survival however, patients tend to be diagnosed in the later stages of disease when treatment is often less effective. Immunotherapy has the potential to reduce MRD and delay or prevent relapse. In order for immunotherapy to work, tumour antigens need to be identified and characterised so they can be effectively targeted. Personalised treatments require the identification of biomarkers, for disease detection and confirmation, as well as to provide an indication of best treatment and the prediction of survival. PASD1 has been found to be frequently expressed in haematological malignancies and I wanted to determine if there was a correlation between the presence of antigen-specific T cells in the periphery of patients with AML and PASD1 protein expression in the leukaemic cells. The expression of other leukaemia antigens were concurrently examined as comparators. I performed RT-PCR on nine antigens and immunocytochemistry on PASD1 in 18 samples from AML patients. I found a correlation between PASD1 expression in AML samples and the presence of PASD1-specific T cells as detected on the pMHC array. OVC lacks suitable targets for immunotherapy with few CTAs having been identified. I examined the expression of SSX2IP and the CTAs PASD1 and SSX2 in OVC. I compared the protein expression of these known tumour antigens to the “gold standard” biomarker for the diagnosis of OVC, CA125 and two other proteins known to be promising in the diagnosis of OVC, HE4 and WT1. I analysed commercially available paraffin-embedded OVC multiple tissue arrays (MTAs) containing 191 samples, predominantly stage I (n= 166), II (n= 15) and III (n= 6) OVC as well as healthy donor (n= 8) and normal adjacent tissues (n= 8). Scoring was performed in a single blinded fashion. I found SSX2A to be expressed at a score level of 3 with a frequency (37/191) that exceeded that of CA125 (14/191), HE4 (14/191), WT1 (1//191) or PASD1 (0/191). To confirm this expression I used two additional commercially-available antibodies that recognise the region common to SSX2A and B, and an antibody specific for SSX2A. Using SSX2 peptides, I blocked the immunolabelling of SSX2 in SSX2-positive cell lines showing that the immunolabelling of SSX2 and SSX2A was specific. I demonstrated that the expression of SSX2 and specifically SSX2A was reproducible and restricted to ovarian cancer with little or no expression in endometrial tissues, or diseased or inflamed endometrial tissue. In summary, these studies demonstrated that PASD1 expression in leukaemia cells correlated with the presence of PASD1-specific T cells in the periphery of presentation AML patients. I have shown that PASD1 specific-T cells are present in AML patients at diagnosis and that immunotherapy targeting PASD1 could be used to break tolerance and clear residual leukaemia cells during first remission. Analysis of the expression of three antigens in OVC, identified the specific expression of SSX2, in particular SSX2A in OVC but not healthy or diseased endometrial tissues. The expression of SSX2A was more frequent and more specific to OVC, than HE4 and WT1, and more frequent at higher intensity, especially in early stage OVC, than CA125. SSX2 and explicitly SSX2A requires further investigation to determine whether the high level of background at score 2 can be reduced with better blocking of non-specific sites. This may require the use of different SSX2 antibodies or an improved staining protocol.

Introdução: O câncer de ovário é o mais prevalente e letal câncer ginecológico. A quimioterapia é um componente importante do tratamento sistêmico clássico com uma combinação de um agente platinado e um taxano, usualmente. Invariavelmente, câncer de ovário avançado torna-se resistente à quimioterapia. Objetivos: Com base em dados recentes que demonstram um possível papel das neurotrofinas na regulação de quimiosensibilidade, decidimos estudar o impacto do fator neurotrófico derivado de cérebro (BDNF) sobre a atividade antitumoral de diferentes classes de agentes antineoplásicos. Métodos: Para avaliar um possível efeito sinérgico entre BDNF e diferentes combinações de tratamento para câncer de ovário, as células foram expostas a cisplatina, etoposideo, doxorrubicina e paclitaxel concomitantemente com BDNF durante 48 horas. Administração sequencial de BDNF e quimioterapia foi realizada para avaliar o potencial de BDNF em modificar a resposta ao tratamento quimioterápico dependendo de qual agente é aplicado em primeiro lugar. Resultados: Houve uma redução da viabilidade de células OVCAR-3 quando expostas a cisplatina, doxorubicina e etoposideo concomitantemente com BDNF em 61,18% (SE±1.12, p=0.002), 38,96% (SE±1.08, p=0.001) e 49,63% (SE±1.17, p<0.001), respectivamente. BDNF também reduziu significativamente o efeito do paclitaxel e doxorrubicina quando usado antes da quimioterapia com uma redução de efeito de 53,46% (SE±3.48, p=0.001) e 48,25% (SE±1.25, p=0.018), respectivamente. Além disso, o BDNF utilizado sequencialmente à doxorrubicina foi capaz de reverter a quimiotoxicidade deste agente em 37,77% (SE±1.25, p=0.018). Conclusão: Utilizando a linhagem celular de câncer de ovário (OVCAR-3), BDNF exibiu um efeito sinérgico quando administrado concomitantemente com os agentes citotóxicos doxorrubicina, etoposideo e cisplatina. Observamos também um efeito protetor de BDNF quando aplicado 24 horas antes de doxorrubicina e paclitaxel. Notavelmente, quando BDNF foi administrado após a exposição a agentes antineoplásicos, uma reversão da citotoxicidade foi observada apenas para a doxorrubicina e não para os outros agentes. / Background: Ovarian cancer is the most prevalent and lethal of gynecological malignancies. Chemotherapy is an important component of the systemic treatment with a combination of a platinum complex and a taxane one of the classic treatments. Invariably, advanced ovarian cancer becomes resistant to chemotherapy. Objective: Based on recent data demonstrating a possible role of neurotrophins regulating chemosensitivity, we decided to study the impact of brain-derived neurotrophic factor (BDNF) on the antitumor activity of different classes of antineoplastic agents. Methods: Primarily, to evaluate a possible synergistic effect of BDNF and different ovarian cancer treatments combination, cells were exposed to cisplatin, etoposide, doxorubicin and paclitaxel concomitantly with BDNF for 48 hours. Sequential administration of BDNF and any of the agents was carried out to evaluate if BDNF has the potential of enhancing or protecting cells from the effects of treatment depending of each agent is applied first. Results: There were a reduction in viability of OVCAR-3 cells exposed to cisplatin, doxorubicin and etoposide when used concomitantly with BDNF in 61.18% (SE 1.12, p=0.002), 38.96% (SE 1.08, p=0.001) and 49.63% (SE 1.17, p<0.001) respectively. We also found that BDNF reduced significantly the effect of paclitaxel and doxorubicin when used before chemotherapy with a reduction of effect of 53.46% (SE±3.48, p=0.001) and 48.25% (SE±1.25, p=0.018), respectively. Furthermore, BDNF used sequentially to doxorubicin was able to reverse the chemotoxicity of this agent in 37.77% (SE 1.25, p=0.018). Conclusion: In conclusion, using the human ovarian carcinoma cell line OVCAR-3, BDNF exhibited a synergistic effect when administered concomitantly to the cytotoxic agents doxorubicin, etoposide and cisplatin. We have also observed a protective effect of BDNF when applied 24 hours before doxorubicin and paclitaxel. Notably, when BDNF was administered after the exposure to the antineoplastic agents, a reversal of cytotoxicity was observed only for doxorubicin and not for the other agents.

Chronic inflammation has been linked to cancer. Prostaglandin E2 (PGE2) is the most pro-inflammatory lipid and one of the downstream products of 2 isoforms of cyclooxygenase (COX) enzymes: COX-1 and COX-2. Although both COX isoforms have similar structure and function, they are encoded by different genes and show distinct expression patterns. COX-1 is expressed in most cells and tissues and remains constant under most physiologic conditions to play a housekeeping role whereas the COX-2 form is inducible and usually only expressed in response to various inflammatory stimuli. COX enzymes may be involved in both tumor establishment and maintenance of existing tumors. PGE2 exerts its effects on target cells by coupling to four subtypes of receptors which have been classified as EP1-4. Ovarian cancer is the most lethal gynecological malignancy and mainly occurs in older women. Prevention may be the best approach to reduce ovarian cancer. Ovarian cancer is the fifth leading cause of cancer death among women and the most lethal gynecological malignancy. There are at least 3 well established risk factors for ovarian cancer: age, family history and environmental factors. Ovarian cancer is mainly seen in older women when their ovaries are not reproductively functional. Close to half of the women with ovarian cancer (48%) are in the age group of 65 or older. Epidemiological and preclinical studies indicate that increased dietary intake of omega-3 fatty acids (OM-3FAs) reduces the incidence and growth of various cancers. Thus, increasing the consumption of OM-3FAs may be a nontoxic way to prevent or suppress ovarian cancer. Flaxseed is the richest vegetable source of omega-3 fatty acids which may be effective in the prevention of ovarian cancer. Fish oil is a source of OM-3FAs which may be effective in prevention of ovarian cancer. The main OM-6FA, Linoleic Acid (LA), is a direct precursor of the Arachidonic Acid (AA). Alpha-linolenic acid (ALA) is the main OM-3FA found in flax oil, whereas eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the OM-3FAs in fish oil. ALA is elongated to form EPA and DHA in the intestine. Celecoxib is a non-steroidal anti-inflammatory (NSAID) drug that selectively inhibits COX-2. There are evidences showing that Celecoxib has some anti-cancer properties. Progress in the treatment and prevention of ovarian cancer has been hampered due to the lack of an appropriate animal model and absence of effective chemo-prevention strategies. The domestic hens spontaneously develop ovarian adenocarcinomas that share similar histological appearance and symptoms such as ascites and metastasis with humans. Our first objective was to investigate the effect of flaxseed supplementation for one year on ovarian cancer and correlate its effects to expression of COX enzymes and concentrations of prostaglandins. White Leghorn hens were fed 10% flaxseed-enriched or standard diet for one year. The severity of ovarian cancer was determined by gross pathology and histology. COX-1 and COX-2 localization and protein and mRNA expression and PGE2 and PGE3 concentrations in ovaries were measured by Immunohistochemistry, western blot, quantitative real-time PCR and LC-MS-MS, respectively. The results demonstrated a significant reduction in late stage ovarian tumors in the flaxseed-fed hens compared with the control diet-fed hens. In correlation with decreased ovarian cancer severity, concentrations of PGE2 and expression of COX-2 were diminished in ovaries of flaxseed-fed hens. PGE3 concentrations were below the level of detection. The results demonstrated that in normal ovaries, COX-1 was localized to the granulosa cell layer surrounding the follicles and ovarian surface epithelium (OSE) whereas COX-2 protein was localized to the granulosa cell layer in the follicle. Extensive COX-1 and COX-2 protein expression was found throughout the ovarian carcinoma. Our findings suggest that the flaxseed-mediated reduction in the severity of ovarian cancer in hens is correlated to the reduction in PGE2 in the ovaries of flaxseed-fed hens. Since no effect on ovarian cancer incidence was detected after feeding the 2. 5 year old hens with 10% flaxseed for 1 year, we designed a long-term study using 6 month old hens. Our objectives were: 1) to examine the expression of COX enzymes and PGE2 levels in ovaries and correlate them to ovarian cancer and aging 2) to determine if long-term consumption of a flaxseed enriched diet decreases ovarian cancer severity and incidence in the laying hen and to investigate its potential correlation with the expression of COX enzymes and PGE2 concentration. White Leghorn hens were fed 10% flaxseed-enriched or standard diet for 4 years. The severity and incidence of ovarian cancer were determined by gross pathology and histology. COX-1 and COX-2 protein and mRNA expression and PGE2 concentrations in ovaries were measured by western blot, quantitative real-time PCR and ELISA, respectively. Our results indicated an increase in ovarian cancer incidence and expression of both COX enzymes in ovaries of older hens. In correlation with ovarian cancer incidence and COX enzymes expression, PGE2 concentrations were elevated with age. Ovaries with tumor had elevated COX-1 expression and PGE2 concentration compared to normal ovaries. Our findings suggest that the up-regulation of COX enzymes with age is the main contributing factor in the age associated increase in PGE2. Furthermore, elevated PGE2 in ovaries of hens concomitant with age suggests its important role in early stages of ovarian carcinogenesis. The results demonstrated that there was a reduction in ovarian cancer severity and incidence in hens fed flaxseed diet. In correlation with decreased ovarian cancer severity and incidence, concentration of PGE2 and expression of COX-2 were diminished in ovaries of hens fed flaxseed. Our findings suggest that the lower levels of COX-2 and PGE2 are the main contributing factors in the chemo-suppressive role of long-term flaxseed consumption in ovarian cancer in laying hens. These findings may provide the basis for clinical trials of dietary intervention targeting prostaglandin biosynthesis for the prevention and treatment of ovarian cancer. Based on our previous findings, targeting COX expression and prostaglandin biosynthesis by dietary intervention using OM-3FAs and selective COX inhibitor can be an effective approach to prevent or suppress ovarian cancer. Thus, we conducted a series of studies to assess effect of fish oil, flax oil, Celecoxib, fish oil and Celecoxib combined or flax oil and Celecoxib combined on COX-1 and COX-2 expression, PGE2 concentrations, proliferation and apoptosis in normal and cancerous ovaries of laying hens. This study had not been performed in hens before, thus the first step was to find the optimum doses. In order to do so, we utilized one year old hens, divided them to groups of 6 hens, and fed them different doses of fish oil (50, 100, 175, 375 and 700 mg/kg), flax oil (100, 250, 500, 1000 and 1500 mg/kg) or Celecoxib (35, 65 and 100 mg/kg) for three weeks. The OM3-FAs andomega-6 fatty acids contents of egg yolks were determined by gas chromatography. Proliferation, apoptosis,COX-1, COX-2 and prostaglandin receptor subtype 4 (EP4) protein and mRNA expression and PGE2 concentration in ovaries were measured by PCNA, TUNEL, western blot, quantitative real-time qPCR and ELISA, respectively. The results indicated that 100 mg/kg fish oil was the most effective dose in reducing COX enzymes and PGE2, and increased apoptosis and reduced proliferation in ovaries. The lower doses of fish oil incorporated more OM-3FAs into yolks, reduced OM-6FAs and increased the egg laying frequency but did not affect EP4 expression. Unlike fish oil, the highest dose of flax oil (1500 mg/kg) caused the most significant reduction in COX expression and PGE2 concentration. Celecoxib was not perfectly selective in targeting COX-2, however, treating the hens with 65 mg/kg Celecoxib resulted in the most significant amelioration of PGE2 levels in ovaries. Using the optimum doses of fish oil, flax oil and Celecoxib, we aimed to investigate if these components can alter ovarian cancer end-points in normal and cancerous hen ovaries. There is an adverse relation between ovulation and health of ovaries. Thus, 3-4 year old hens were monitored for egg laying frequency and the hens with the least ovulation rate were selected for health assessment. The hens presenting poor health were scanned using ultrasound and if tumor mass and/or ascites were detected, they were chosen for this study. The hens with normal and cancerous ovaries were divided to groups and were fed fish oil, flax oil, Celecoxib, fish oil and Celecoxib combined, or flax oil and Celecoxib combined for 42 days. The results showed that fish oil and flax oil increased the incorporation of OM-3FAs into egg yolks in both normal and cancerous ovaries of hens. Fish oil reduced COX-1 and COX-2 in normal and cancerous ovaries. Fish oil, flax oil and Celecoxib reduced the COX-2 expression in ovaries. Combination of fish oil and Celecoxib and flax oil and Celecoxib decreased COX and PGE2 more than each of these treatments alone. The cancerous ovaries of hens treated with fish oil, flax oil, Celecoxib, and flax oil and Celecoxib combined increased the percentage of apoptotic cells compared to cancerous ovaries of control hens. The cancerous ovaries of hens treated with fish oil and Celecoxib had the highest number of apoptotic cells indicating that the combination of fish oil and Celecoxib is more effective than fish oil or Celecoxib alone. To our knowledge the present study provides the first insight into the efficacy of fish oil, flax oil, Celecoxib, alone or combined on the reduction of COX enzyme expression, PGE2 concentration and apoptosis in the normal and cancerous ovaries and further demonstrates the utility of the hen model for ovarian cancer. Our studies provided new insight into the potential mechanism of action of flaxseed, fish oil, flax oil and Celecoxib in the reduction of ovarian cancer and will establish the foundation for clinical trials to test the efficacy of dietary intervention for the prevention and suppression of ovarian cancer in women.