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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
551

Regulation of Steroid Receptor Activity in the Breast and Urogenital Tract

Rosenblatt, Adena 16 July 2009 (has links)
Steroid receptors are important in the pathogenesis of a variety of disease states and modulate cellular processes through differential gene expression. Therefore, understanding the regulation of steroid receptors is essential. Environmental sodium arsenite, a toxin associated with male infertility, and arsenic trioxide, a possible prostate cancer therapeutic agent, are inorganic trivalent semimetals. The mechanism of arsenic action in male urogenital tract tissues is not clear. Since androgen receptor (AR) plays an important role in spermatogenesis and prostate cancer, we explored the possibility that trivalent arsenic regulates AR function. We found that arsenic inhibited AR transcriptional activity in prostate cancer and Sertoli cells by inhibiting AR recruitment to an AR target gene enhancer in vivo. Consistent with a deficiency in AR chromatin binding, arsenic disrupted AR amino and carboxyl-termini interaction. Furthermore, ATO caused a significant decrease in prostate cancer cell proliferation that was more pronounced in cells expressing AR compared to cells depleted of AR. Thus, arsenic-induced male infertility may be due to inhibition of AR activity and arsenic may serve as an effective therapeutic option in prostate cancer. Rac1, a Rho GTPase, modulates a variety of cellular processes and is hyperactive in cancer. Estrogen receptor (ER) regulates genes associated with cell proliferation, tumor development, and survival in breast cancer. Therefore, we examined the possibility of crosstalk between Rac1 and ER signaling. We found that Rac1 enhanced ER transcriptional activity in breast cancer cell lines. Vav3, a Rho guanine nucleotide exchange factor, was an upstream activator and P21/Cdc42/Rac1 activating kinase-1 (PAK-1) was a downstream effector of Rac1 enhancement of ER activity. These results suggest that Rac1 may be a beneficial therapeutic target. To test this hypothesis, we used EHT 1864, a small molecule Rac1 inhibitor. EHT 1864 inhibited ER transcriptional activity and estrogen-induced breast cancer cell proliferation. Furthermore, EHT 1864 inhibited ER activity by downregulation of ER mRNA and protein levels. Since ER plays a critical role in the pathogenesis of breast cancer and EHT 1864 inhibits ER activity and breast cancer cell proliferation, Rac1 inhibition is a novel and compelling therapeutic target in breast cancer.
552

Prostate cancer : epidemiological studies of risk factors

Thellenberg Karlsson, Camilla January 2008 (has links)
In spite of the fact that prostate cancer is the most common male cancer in both Sweden and many other countries in the developed world, little is known of risk factors and predisposing conditions. The only well recognized risk factors are age, race and familial aggregation. More knowledge about risk factors could lead to better preventive measures together with better treatments. One way to evaluate this is to study second primary cancers; the connection between two different cancers can give valuable insight in etiology or clues to shared risk factors. This thesis aims at evaluating risk factors for prostate cancer. We constructed a cohort of 135,713 men diagnosed with prostate cancer and reported to the Swedish Cancer Registry 1958-1996. The cohort was followed for second primary cancers and a doubled risk of male breast cancer was found. We also noted increased risks for small intestine cancers and melanoma. As a follow-up on the increased risk of male breast cancer, we performed a nested case – control study. Included cases were men with first prostate and then breast cancer (n = 41) matched to men with only prostate cancer (n =81). For these men, we collected medical records and extracted data regarding treatment. Furthermore, all men diagnosed with both prostate and breast cancer irrespective which came first (n = 83) were used as probands. To both these sets of cases with breast and prostate cancer, we identified first degree relatives and grandchildren from parish offices throughout Sweden. Linking to the Cancer Registry retrieved all cancer diagnoses amongst relatives. Results from this study show a relation between estrogen treatment of prostate cancer and the risk of developing breast cancer. We also found that a small part of the cases with both cancers appeared in families with inheritance patterns possibly attributed to BRCA2. As estrogen treatment seemed involved in increased risk of breast cancer after prostate cancer, we wanted to investigate the newly discovered Estrogen receptor β and the relation to prostate cancer risk. Previous reports have shown that ERβ acts as a negative regulator of proliferation. ERβ expression occurs mainly in prostatic epithelial cells and the expression gradually diminishes when cancer develops and aggravates. We used a single nucleotide polymorphism (SNP) association study approach to evaluate genetic variation in ERβ as a risk factor for prostate cancer. One SNP, located in the promoter region associated with a small increased risk of prostate cancer whereas variation in the rest of the gene did not. In the last paper, we investigated trans-urethral resection (TURP) of the prostate due to benign prostate hyperplasia (BPH) as a risk factor for later development of prostate cancer. Evidence has gathered that both BPH and prostate cancer are associated to inflammation. By comparing incidence and mortality in a cohort of 7,901 men with the general population there appeared to be an increased risk of prostate cancer but decreased mortality. Analyzing this increased risk further, we conducted a nested case - control study with men extracted from the cohort. Cases had a TURP and later developed prostate cancer and controls just had a TURP. We then evaluated the specimens from TURP regarding extent of inflammation, degree of androgen receptor down regulation and expression of p53, all factors previous associated with prostate cancer. None of these parameters differed between cases and controls and they can therefore not explain the increased risk. Decreased mortality but increased risk might be explained by surveillance bias, which means more medical attention to these patients, resulting in diagnosing clinically non-significant cancers. In summary, our results show a doubled risk of male breast cancer following prostate cancer. A risk that can be attributed to the use of estrogen to treat prostate cancer or to some extent a possible mutation in BRCA2. We also propose that a SNP change in the ERβ promoter confer a small increased risk of prostate cancer. A small risk elevation of prostate cancer following TURP most probable could depend on surveillance bias.
553

Metastatic spinal cord compression in prostate cancer : clinical and morphological studies / Ryggmärgskompression vid metastaserande prostatacancer : kliniska och morfologiska studier

Crnalic, Sead January 2012 (has links)
Background: Bone metastases occur in most patients with advanced hormone-refractory prostate cancer causing pain, pathologic fractures, and spinal cord compression. Few studies specifically address surgical treatment of metastatic spinal cord compression (MSCC) in prostate cancer. Criteria for identifying patients who may benefit from surgery are poorly defined. Most of the current knowledge regarding tumor biology in prostate cancer is based on studies of primary tumors or soft tissue metastases. The mechanisms regulating growth of bone metastases are not fully established. Aims: a) to evaluate outcome after surgery for MSCC in prostate cancer and to identify prognostic factors for survival and functional recovery; b) to evaluate current practice for referral of prostate cancer patients with MSCC; c) to analyze expression of androgen receptor (AR), cell proliferation, apoptosis, and prostate-specific antigen (PSA) in bone metastases with regard to survival after surgery for complications of bone metastases. Patients and Methods: We retrospectively evaluated the hospital records of 68 consecutive patients operated for metastatic spinal cord compression. Tumor tissue from bone metastases was obtained on spinal surgery (54 patients), fracture surgery (4 patients) and biopsy (2 patients), and analyzed by immunohistochemistry. Results: Study I: Mortality and complication rate after surgery was high. Patients with hormone-naïve disease and those with hormone-refractory disease with good performance status and without visceral metastases had more favorable survival. The ability to walk after surgery was related to better survival. Study II: A new score for prognosis of survival after surgery for spinal cord compression includes: hormone status of prostate cancer, Karnofsky performance status, evidence of visceral metastasis, and preoperative serum PSA. The score is simple, tumor specific, and easy to apply in clinical practice. Study III: Our results suggest that delays in diagnosis and treatment may have negative impact on functional outcome. Pretreatment ability to walk, hormone status of prostate cancer, and time from loss of ambulation influenced neurological recovery after surgery for spinal cord compression. Study IV: High nuclear AR immunostaining in bone metastases and high preoperative serum PSA were associated with a poor outcome after metastasis surgery in patients with hormone-refractory prostate cancer. Short-term effect of castration therapy disclosed that nuclear AR immunostaining was decreased and apoptosis was increased, but cell proliferation remained largely unaffected. Conclusion:  Prostate cancer patients with metastatic spinal cord compression represent a heterogeneous group. We identified prognostic factors for survival and functional outcome, which may help clinicians in making decisions about treatment. Our results also implicate the need for development of local and regional guidelines for treatment of patients with spinal cord compression, as well as the importance of information to patients at risk.
554

Molecular Genetic Studies on Prostate and Penile Cancer

Andersson, Patiyan January 2008 (has links)
This thesis is comprised of two parts. In the first part we study the influence of four frequently disputed genes on the susceptibility for developing prostate cancer, and in the second part we attempt to establish a basic understanding of the molecular genetic events in penile cancer. In a prostate cancer cohort we have investigated the relation of prostate cancer risk and single nucleotide polymorphisms (SNPs) in four different genes coding for the androgen receptor (AR), the vitamin D receptor (VDR), insulin (INS) and insulin receptor substrate 1 (IRS1). Despite strong biological indications of an involvement of these genes in prostate carcinogenesis, the results from different studies are contradictory and inconclusive. The action of the AR varies between individuals in part owing to a repetitive CAG sequence (polyglutamine) in the first exon of the AR gene. The results presented in this thesis show that in our cohort of prostate cancer patients the average number of repeats is 20.1, which is significantly (p<0.001) fewer repeats compared to healthy control individuals, where the average is 22.5 repeats. We find a 4.94 fold (p=0.00003) increased risk of developing prostate cancer associated with having short repeat lengths (≤19 repeats), compared with long repeats (≥23 repeats). In paper I we also study the TaqI polymorphism in the VDR gene, and find that it does not modify the risk of prostate cancer. In the INS gene we study the +1127 PstI polymorphism and find no overall effect on the risk of prostate cancer. However, we do find that the CC genotype is associated with low grade disease defined as having a Gleason score ≤6 (OR=1.46; p=0.018). In the IRS1 gene we study the G972R polymorphism and observe that the R allele is significantly associated with a 2.44 fold increased prostate cancer risk (p=0.010). The knowledge of molecular genetic events in penile cancer is very scarce and to date very few genes have been identified to be involved in penile carcinogenesis. We chose therefore to analyse the penile cancer samples using genome-wide high-density SNP arrays. We find major regions of frequent copy number gain in chromosome arms 3q, 5p and 8q, and slightly less frequent in 1p, 16q and 20q. The chromosomal regions of most frequent copy number losses are 3p, 4q, 11p and 13q. We suggest four candidate genes residing in these areas, the PIK3CA gene (3q26.32), the hTERT gene (5p15.33), the MYC gene (8q24.21) and the FHIT gene (3p14.2). The mutational status of the PIK3CA and PTEN genes in the PI3K/AKT pathway and the HRAS, KRAS, NRAS and BRAF genes in the RAS/MAPK pathway was assessed in the penile cancer samples. We find the PIK3CA, HRAS and KRAS genes to be mutated in 29%, 7% and 3% of the cases, respectively. All mutations are mutually exclusive. In total the PI3K/AKT and RAS/MAPK pathways were found to be activated through mutation or amplification in 64% of the cases, indicating the significance of these pathways in the aetiology of penile cancer.
555

Att leva med kroppsliga förändringar vid obotlig cancersjukdom med fokus på prostatacancer : ”jag är frisk – bortsett från att jag har cancer som är dödlig, men det är liksom en annan sak”

Lindqvist, Olav January 2007 (has links)
The overall aim of this thesis is to illuminate and describe bodily changes and problems in incurable cancer, with focus on prostate cancer, from the patient’s perspective. The thesis consists of four papers, each of which illuminates various aspects of the phenomenon studied. The study population consisted of 24 participants, three women with different cancer diagnoses in the palliative phase, and 21 men with hormone refractory prostate cancer (HRPC) and skeletal metastases. Data are based on interviews (papers I–IV) and a quality of life questionnaire (paper I). The study design is cross-sectional (papers I–III) and longitudinal (paper IV). Qualitative description, descriptive statistics, phenomenological hermeneutics, and analysis of discourse were used to analyze data. The findings of study I show that the dominating symptoms for the men with HRPC (n=20) were pain and fatigue, and three different variants of each problem were described. The men said that changes in their sex life were not an extensive problem, even if it was scored as such. The symptoms differed in occurrence, extent, and meaning between the men, and were not necessarily experienced as problems. In study II, pain and fatigue were again the most prominent problems in men with HRPC (n=18), but pain and fatigue were seen to have different meanings. Pain was seen as synonymous with cancer. Pain can be alleviated, but it is a threat, both now and in the future, and symbolizes a painful death. Fatigue was viewed as a hindrance in the present. It was experienced as less threatening than pain, but as something that cannot really be changed. Fatigue represents the natural course death will take, as eventually sleep into death. An important finding of study II is that one meaning of bodily problems is to live in a cyclical movement of losing and reclaiming wellness. Understanding, and, to some extent, being in control of, bodily problems makes it possible to experience wellness. When the bodily problems increase or change, or when new problems appear or become a hindrance in the daily life, the experience of being ill returns. The findings of study III show that one meaning of fatigue in patients with cancer in the palliative phase (n=4) is a lived bodily experience of approaching death. This can be understood through the paradox of struggling against fatigue, and hoping to overcome it, yet expecting failure. The body, through fatigue, signals to the person that death is approaching, but the person is not yet “ready”. Paper IV shows that the way two of the men with HRPC talked about the past, present, and future changed during the disease trajectory. In the first interview, the men were open towards both the past and the future, while just before death, their narration was totally dominated by the concrete experience of the illness. The past became the past in the illness and not in life, and the present was flooded with extensive bodily changes. Also, the future had shrunk, although it also had been transferred to beyond death. Pain, fatigue, nausea, and other bodily problems figured largely in this change. This thesis provides important insights into the phenomenon of bodily changes when living with incurable cancer, with focus on prostate cancer. The thesis shows the connection between bodily changes and time, where different bodily changes have different meanings, and meanings seem to change during the illness trajectory (papers I–IV); and bodily changes close to death seem to take “all” time; what is left is the present filled with problems (paper IV). Further, it shows that bodily changes have a great influence on the cyclical movement between losing and reclaiming wellness in incurable cancer (paper II). The clinical implications of the thesis are that alleviation of pain and other bodily problems must be based on the meaning the patient gives the bodily changes taking place. That is, alleviation with the purpose to free time and to facilitate living in wellness as death is approaching.
556

Genetic variation and prostate cancer : population-based association studies in Sweden

Lindström, Sara January 2007 (has links)
Prostate cancer constitutes the most common malignancy and the most common cause of cancer‐related death in Swedish men. A large body of evidence suggests that inherited genetic variants contribute to both development and progression of prostate cancer. The aim of this thesis is to identify genetic variants that alter prostate cancer risk and progression. All papers included in this thesis are based on a Swedish population‐based case‐control study (CAPS) comprising 2,965 incident prostate cancer cases and 1,823 controls. In paper I, we investigated if genetic variants in the E‐cadherin gene altered prostate cancer risk. Seven haplotype tagging SNPs(tagSNPs) were selected and genotyped in CAPS and families with hereditary prostate cancer. We confirmed association of a promoter SNP rs16260 previously reported to increase risk of hereditary prostate cancer (OR: 2.6; 95% CI: 1.6‐4.3) for homozygous ‘A’ carriers. In paper II, we assessed 46 polymorphisms earlier reported to be associated with prostate cancer risk. Six polymorphisms in five different genes were replicated. Interestingly, three of these genes were involved in the androgen biosynthesis. In paper III, we followed up on the results from paper II by genotyping 23 tagSNPs located in the hormone regulating genes AR, CYP17 and SRD5A2. Multiple SNPs and haplotypes were associated with prostate cancer risk, especially in the AR gene. Combining risk alleles from all genes revealed a substantial risk increase for each additional allele carried (OR: 1.12; 95% CI: 1.1‐1.2, P=0.00009). In paper IV, we collected information about cause of death for all case patients in CAPS. At time of follow‐up 300 study subjects were deceased from prostate cancer. We assessed AR, CYP17 and SRD5A2 variants for association with lethal prostate cancer and found overall no association. However, one AR promoter SNP was associated with an increased risk of dying from prostate cancer amongst men who received palliative hormonal therapy as primary treatment. In paper V, we assessed common genetic variation at the ERG locus for association between prostate cancer risk and survival. ERG is recognized as a protooncogene frequently overexpressed in prostate cancer. A total of 21 tagSNPs in the 5’ region of ERG were genotyped. There was no correlation between ERG SNPs and prostate cancer risk but common genetic variation located approximately 100,000 basepairs upstream of ERG was significantly associated with prostate cancer specific survival. In summary, our results suggest that common genetic variation in Ecadherin alters prostate cancer risk in Swedish men with a positive family history of prostate cancer. Moreover, common genetic variation in the androgen‐related genes AR, CYP17 and SRD5A2 affects the risk of developing prostate cancer but is unlikely to alter prostate cancer progression. However, genetic variants in AR may affect hormonal therapy response. Finally, ERG polymorphisms are associated with prostate cancer‐specific death but are not likely to play a role in prostate cancer development.
557

Prostate cancer and inflammatory genes

Lindmark, Fredrik January 2005 (has links)
Prostate cancer remains a significant health concern for men throughout the world. Accumulating epidemiologic and molecular evidence suggests that inflammation is an important component in the aetiology of prostate cancer. Supporting this hypothesis, population studies have found an increased risk of prostate cancer in men with a prior history of certain sexually transmitted infections or prostatitis. More general evidence of a relationship between inflammation and prostate cancer has been provided by reports indicating that daily use of non steroidal anti-inflammatory drugs (NSAIDs) may be associated with a lower incidence of prostate cancer. The exact mechanism whereby inflammation might act in tumour development and progression remains to be elucidated, but is likely to be complex. The genetic contribution to inflammatory responses involved in the development of prostate cancer has not yet been extensively or systematically studied. However, this thesis evaluates the role of various inflammation-related genes in the pathogenesis of prostate cancer. The macrophage scavenger receptor 1 (MSR1) is a transmembrane protein that is mainly expressed by macrophages. This receptor mediates the binding, internalization and processing of a wide range of macromolecules, and is suggested to play a major role in the recognition and clearance of pathogenic and damaged cells. Recent reports have suggested MSR1 to be a candidate gene for hereditary prostate cancer. Therefore, we screened the MSR1 gene among men with hereditary prostate cancer and identified 18 sequence variants. One previously reported truncation mutation was found more frequently in men with prostate cancer than in unaffected men, in accordance with previously published results. However, the difference in frequencies we found between these groups was not statistically significant. In addition, we genotyped five common polymorphisms in MSR1 in 215 men with unselected prostate cancer and 425 controls. No association between any of the five common variants and prostate cancer were found. We then performed a comprehensive genetic study using extensive populationbased case-control material to evaluate possible associations between sequence variants in inflammation-related genes and prostate cancer. The first gene to be examined was interleukin-1 receptor antagonist (IL-1-RN), encoding a cytokine that plays an important role in regulation of the inflammatory response by binding to the IL-1 receptor and thus inhibiting the binding of the pro-inflammatory cytokines IL-1α and IL-1β. Collectively, these three cytokines exert a central role in the protection against diverse lesions, ranging from microbial colonisation to infection and malignant transformation. The genetic analysis of IL-1RN revealed that the most common haplotype was significantly associated with prostate cancer risk for patients with prostate cancer, and further this association appears to be stronger in cases with advanced disease. The macrophage inhibitory cytokine-1 (MIC-1), a member of the transforming growth-factor-β superfamily has been shown to exert diverse biological functions, including regulation of macrophage activity in the inflammatory response and both growth inhibition and induction of apoptosis in epithelial and other tumour cell lines. The genetic analysis of MIC-1 revealed that a seuqence variant (H6D) appears to be associated with a decreased prostate cancer risk. We also performed measurements of MIC-1 serum levels among patients with prostate cancer and healthy controls. These data indicate that serum MIC-1 levels are associated with an increased risk for prostate cancer. Further, the clear relation between clinical stage and MIC-1 level also suggest that MIC-1 may be useful as a prognostic factor, where high serum concentration is associated with a poor prognosis. In summary, our results provide further support for the assumption that polymorphisms in inflammatory genes play critical roles in prostate cancer susceptibility. Additional studies are needed to elucidate the mechanisms whereby the demonstrated variations contribute to prostate cancer development.
558

Expression and prognostic value of LRIG1 and the EGF-receptor family in renal cell and prostate cancer

Thomasson, Marcus January 2009 (has links)
The epidermal growth factor receptor (EGFR) family consists of four (EGFR, ErbB2, Erbb3, and ErbB4) receptor tyrosine kinases (RTK) whose signalling is important for physiological and malignant cellular functions such as proliferation, survival, migration, and differentiation. EGFR and ErbB2 in particular are established oncogenes in many solid tumours and are targets for anti-cancer treatment. LRIG1 (leucine-rich repeats and immunoglobulin-like domains-1) is a protein that negatively regulates the EGFR-family, and other RTKs and is a proposed tumour suppressor. This thesis examines the expression of the EGFR-family members and LRIG1 in renal cell carcinoma (RCC) and in prostate cancer (PC). In RCC, up-regulation of EGFR was shown for all RCC types analysed: clear cell (ccRCC), papillary (pRCC), and chromophobe (chRCC). ErbB2 was down-regulated in ccRCC. ErbB3 expression was low in non-neoplastic kidney and not significantly altered in RCC. ErbB4 was strongly down-regulated in the vast majority of RCCs of all types. LRIG1 was down-regulated in ccRCC. No prognostic value was found for any of these factors in RCC. In prostate cancer cells, LRIG1 was shown to be up-regulated by androgen stimulation and suppressed the growth of prostate cancer cells. In prostate cancer, the expression and prognostic value of LRIG1 was investigated in two patient series, one with untreated patients and one with patients who had undergone prostatectomy. In the untreated patient series, LRIG1 correlated with malignancy grade (Gleason score) and poor outcome for patients (both cancer specific and overall survival), being an independent prognostic factor. In contrast, in the series of patients who had undergone prostatectomy, LRIG1 expression correlated with a good outcome (overall survival). Thus in RCC, there were alterations in gene-expression of the EGFR-family members and LRIG1 between kidney cortex and RCC and between the RCC types. Despite few associations with clinical factors, these alterations are likely to be of biological importance. In prostate cancer LRIG1 was up-regulated by androgen stimulation and inhibited cell proliferation. LRIG1 expression had prognostic value in prostate cancer, maybe as a secondary marker of androgen receptor activation or because of growth inhibition of prostate cancer cells. Contradicting findings in untreated patients and patients treated with prostatectomy poses the question of whether the prognostic value of LRIG1 and other markers vary depending on the specific biological and clinical circumstances in the materials studied.
559

Examining the prostate stroma and vasculature : importance and potential as targets for therapy

Johansson, Anna January 2008 (has links)
Background. Recent studies in cancer research have focused on the reciprocal interaction between cancer cells and their microenvironment. Tumour growth is angiogenesis dependent and the rate of angiogenesis correlates with a poor prognosis in many different cancers. We have shown that the rate of angiogenesis correlates with prognosis in Prostate Cancer (PC). We have also observed that the vasculature is involved during the involution of the prostate in rodents subsequent to hormonal ablation. Patients with metastatic PC are subjected to hormonal ablation therapy – a therapy unfortunately not curative. Our ambition is therefore to find means to enhance the effects of castration therapy of prostate tumours, possibly by a simultaneous inhibition of angiogenesis and of growth factors populating the tumour stroma. The angiopoietins are a family of growth factors that regulate angiogenesis by direct effects on endothelial cells in a context dependent manner. The purpose of this thesis was therefore to examine the role of the angiopoietins and the stroma in general in PC and to explore their potential as novel targets. Materials and Methods. We have had at our disposal access to clinical materials in the form of paraffin embedded samples from untreated PC patients with a long follow up. We have also used animal tumour models and in vitro cell culture systems followed by immunohistochemistry, in situ hybridization, western blotting, laser micro dissection, and quantitative real-time PCR for evaluation of the experiments. Results. In paper I, we found a significant correlation between high levels of angiopoietin 2 (Ang 2) and high vascular density, histological grade, metastases and poor prognosis in PC patients. In the second paper we found that the receptor for the angiopoietins, Tie 2, and the ligand Ang 1 mediated the decrease in vascular stability observed after castration treatment. This was not observed in prostate tumours subsequent to hormonal ablation (paper III), nor was there a decrease of other growth factor receptors. In summary (paper III), we found that a combined inhibition of the tumour stroma in terms of an inhibition of the PDGF-Rs by the use of Imatinib, and the vasculature in terms of a perturbed Tie 2 signalling, inhibited tumour growth. Finally, in paper IV, we found that Imatinib inhibited the castration induced influx of mast cells after castration therapy. The mast cells expressed high levels of FGF 2 and epiregulin, and inhibition of mast cell function inhibited tumour growth, by inhibiting angiogenesis. Conclusions. We have observed that the tumour stroma is of particular importance for tumour growth in PC. Targeting the tumour microenvironment, and in particular by a simultaneous inhibition of the vasculature and stroma, could prove beneficial for patients with advanced PC.
560

Generation of Therapeutic T Cells for Prostate Cancer

Forsberg, Ole January 2009 (has links)
The work presented herein focuses on the activation of the adaptive immune system in order to develop T cell-based immunotherapy for viral infections and cancer. The main goal was to identify and activate viral or tumoral antigen-specific T cells by using different identification, isolation and stimulation techniques. One such approach was that we modified dendritic cells (DCs) with an adenoviral vector encoding the full length pp65 antigen from cytomegalovirus (CMV). Through strategic modification techniques we demonstrate that it is possible to obtain DCs presenting antigen-specific peptides both on major histocompatibility complex (MHC) class I and MHC class II molecules for simultaneous CD8+ and CD4+ T cell activation. We also demonstrate that it is possible to generate prostate antigen-specific CD8+ T cells from a naïve repertoire of T cells by using DCs and HLA-A2-restricted peptides derived from prostate tumor-associated antigens or by using an adenoviral vector encoding the full length prostate tumor-associated antigen STEAP. We further demonstrate that CD8+ T cells directed against several prostate-specific peptide epitopes can be found in peripheral blood and in the prostate tumor area of prostate cancer patients. Furthermore, we have characterized a number of prostate-derived cell lines in terms of HLA haplotype and tumor-association antigen expression. We concluded that our methods for generating T cells restricted to CMV antigen have the ability to be applied for adoptive T cell transfer to patients with CMV disease and that prostate antigen-specific T cells can be found within prostate cancer patients, which enables future development of immunotherapeutic strategies for prostate cancer.

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