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Antiangiogenic and finasteride therapies: Responses of the prostate microenvironment in elderly mice. Life Sci 2014; 106:58-70. [DOI: 10.1016/j.lfs.2014.04.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 04/14/2014] [Accepted: 04/19/2014] [Indexed: 01/05/2023]
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Karagiannis GS, Saraon P, Jarvi KA, Diamandis EP. Proteomic signatures of angiogenesis in androgen-independent prostate cancer. Prostate 2014; 74:260-72. [PMID: 24166580 DOI: 10.1002/pros.22747] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 09/30/2013] [Indexed: 12/30/2022]
Abstract
INTRODUCTION The observation that angiogenesis, the process of new blood vessel formation, in healthy prostate and early prostate cancer is androgen-dependent gave rise to significant questions on how hypervascularization and increased angiogenesis is also achieved at the molecular level in advanced androgen-independent prostate cancer. The exact paracrine molecular network that is hardwired into the proteome of the endothelial and cancer subpopulations participating in this process remains partially understood. METHODS Here, we interrogated the signaling pathways and the molecular functional signatures across the proteome of endothelial cells after interacting with various secretomes produced by androgen-dependent and -independent prostate cancer cells. RESULTS We found the significant overexpression (P < 0.05) of prominent markers of angiogenesis, such as vonWillebrand factor (vWF) (∼ 2.5-fold) and CD31 (∼ 2-fold) in HUVECs stimulated with conditioned media from the androgen-independent prostate cancer cell line PC3. By mining the proteome of PC3 conditioned media, we discovered a signature of chemokine CXC motif ligands (i.e., CXCL3, CXCL5, CXCL6 and CXCL8) that could potentially coordinate increased angiogenesis in androgen-independent prostate cancer and verified their increased expression (P < 0.05) in both in vitro and xenograft models of androgen-independence. DISCUSSION Our findings form the basis for understanding the regulation of crucial metastatic phenomena during the transition of androgen-dependent prostate cancer into the highly aggressive, androgen-independent state and provide further insight on potential therapeutic targets of cancer-related angiogenesis.
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MESH Headings
- Androgens/pharmacology
- Cell Line, Tumor
- Chemokines, CXC/analysis
- Chemokines, CXC/genetics
- Culture Media, Conditioned/chemistry
- Endothelium, Vascular/chemistry
- Endothelium, Vascular/metabolism
- Gene Expression
- Human Umbilical Vein Endothelial Cells
- Humans
- Male
- Neovascularization, Pathologic/metabolism
- Platelet Endothelial Cell Adhesion Molecule-1/analysis
- Platelet Endothelial Cell Adhesion Molecule-1/genetics
- Prostatic Neoplasms/blood supply
- Prostatic Neoplasms/metabolism
- Prostatic Neoplasms, Castration-Resistant/blood supply
- Prostatic Neoplasms, Castration-Resistant/metabolism
- Proteomics
- RNA, Messenger/analysis
- Signal Transduction
- von Willebrand Factor/analysis
- von Willebrand Factor/genetics
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Affiliation(s)
- George S Karagiannis
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
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Verdoorn BP, Feng C, Ricke WA, Sahasrabudhe DM, Kilari D, Kohli M. An observational study of plasma vascular endothelial growth factors (VEGF) A and D expression in non-localized prostate cancer. JOURNAL OF MENS HEALTH 2012; 9:182-189. [PMID: 24416090 DOI: 10.1016/j.jomh.2012.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND The aim of the study was to measure plasma levels of the vascular endothelial growth factors (VEGF) A and D in serially collected blood specimens from non-localized prostate cancer (PCa) subjects. METHODS Plasma VEGF A and D levels were measured in two serial specimens 3-6 months apart in two groups of non-localized stage PCa patients. Group 1 was comprised of patients with biochemical relapse after localized PCa treatments and/or patients with clinically metastatic hormone-sensitive stage PCa prior to receiving hormonal therapy. Group 2 included patients failing hormonal therapy for non-localized hormone-sensitive stage PCa. VEGF A and D levels were compared within each cancer group between the two time-points using the Wilcoxon Rank Sum test. RESULTS At the first time-point in Group 1 (n = 46), median VEGF-A and D levels were measured at 5.2 (pg/ml) (range = 0-97) and 319 (range = 172-780) (pg/ml). For Group 2 (n = 34) VEGF-A level was 9.6 pg/ml (range = 0-78) and VEGF-D level was 377 pg/ml (range = 243-989) for the first measurement. Median time-period for the serial second specimen was 189 days in Group 1 and 84 days in Group 2. At the second time-point, in Group 1, VEGF-A levels were 0.0 pg/ml (P = 0.0002) while VEGF-D increased to 349 pg/ml (P = 0.002). For Group 2 patients at the second time-point, median VEGF-A was 0.0 pg/ml (P = 1.0) and VEGF-D was measured at 442 pg/ml (P = 0.008). CONCLUSIONS Higher plasma VEGF-D than VEGF-A expression in advanced PCa stages suggests a greater role for VEGF-D dependent lymph angiogenesis in advanced stage PCa, which needs further evaluation.
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Tomić TT, Gustavsson H, Wang W, Jennbacken K, Welén K, Damber JE. Castration resistant prostate cancer is associated with increased blood vessel stabilization and elevated levels of VEGF and Ang-2. Prostate 2012; 72:705-12. [PMID: 21809353 DOI: 10.1002/pros.21472] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 07/13/2011] [Indexed: 11/09/2022]
Abstract
BACKGROUND Angiogenesis is important for the progression of prostate cancer and may be a target for treatment in castration resistant (CR) disease. This study was performed to investigate blood vessel stabilization and expression of the pro-angiogenic factors vascular endothelial growth factor (VEGF) and Angiopoietin-2 (Ang-2) in CR and hormone naïve (HN) prostate cancer. The effect of androgen deprivation therapy (ADT) on these parameters was also studied. METHODS VEGF and Ang-2, as well as pericyte coverage of blood vessels were studied in HN and CR prostate tumors by immunohistochemistry. The effects of ADT on VEGF expression and microvessel density (MVD) were investigated in biopsies at diagnosis, 3 months after starting ADT and at tumor relapse. Plasma was also analyzed for VEGF and Ang-2 with ELISA. RESULTS CR tumors had higher levels of VEGF and Ang-2 as well as increased blood vessel stabilization compared to HN tumors. Three months after initiated ADT an increase of VEGF but not MVD in the tumors was observed. In contrast, plasma levels of VEGF decreased after ADT, and increased again at time of tumor relapse. Ang-2 levels were unaffected. CONCLUSIONS CR prostate cancer is associated with elevated levels of VEGF and Ang-2, indicating that these factors could be used as targets for anti-angiogenic treatment. Still, the observed increase in blood vessel stabilization in CR tumors could influence the outcome of anti-angiogenic treatment. Furthermore, increased VEGF expression after 3 months of ADT justifies the use of VEGF-based anti-angiogenic drugs in combination with ADT for the treatment of advanced prostate cancer.
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Affiliation(s)
- Tajana Tešan Tomić
- Sahlgrenska Cancer Center, Department of Urology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
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Rudolfsson SH, Bergh A. Hypoxia drives prostate tumour progression and impairs the effectiveness of therapy, but can also promote cell death and serve as a therapeutic target. Expert Opin Ther Targets 2008; 13:219-25. [DOI: 10.1517/14728220802626249] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Laitinen S, Martikainen PM, Tammela TLJ, Visakorpi T. Cellular Changes in Prostate Cancer Cells Induced by Intermittent Androgen Suppression. Eur Urol 2007; 52:725-32. [PMID: 17141945 DOI: 10.1016/j.eururo.2006.11.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Accepted: 11/21/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES This study used tumour specimens from a clinical trial on intermittent androgen suppression (IAS) to study the effects of castration on tissue morphology, cell proliferation, apoptosis, and the expression of androgen receptor (AR). METHODS A total of 113 representative needle biopsy specimens were available from 29 patients for evaluation of the Gleason score as well as Ki-67, cleaved caspase-3, and AR immunostaining. RESULTS At 6 mo from the beginning of the first androgen withdrawal, cell proliferation activity was significantly (p = 0.002) reduced, whereas no effect on apoptosis was found. A nonsignificant trend to an increase in Gleason score after castration was found. Subsequent cycles of withdrawals had no significant effect on any of the measured parameters. The Gleason score, proliferation activity, and apoptosis rate showed only heterogeneous, nonsignificant changes after the first progression. Strong nuclear AR staining was evident in all cancer specimens. CONCLUSIONS The findings suggest that the long-term (months) effect of androgen withdrawal on tumour growth is due to the inhibition of proliferation. Because the tumours seem to become resistant to castration at the first cycle of treatment withheld, it is possible that IAS does not postpone the emergence of ablation-resistant tumours. There was no consistent sign of increased proliferation or Gleason score during the treatment, suggesting that the biologic aggressiveness of a particular tumour is defined already at an early stage of disease. The constant nuclear expression of AR in cancer cells indicates that the AR signalling remains active despite of the androgen withdrawal.
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Affiliation(s)
- Sari Laitinen
- Cancer Genetics, Institute of Medical Technology, University of Tampere and Tampere University Hospital, Tampere, Finland
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Shidaifat F, Gharaibeh M, Bani-Ismail Z. Effect of castration on extracellular matrix remodeling and angiogenesis of the prostate gland. Endocr J 2007; 54:521-9. [PMID: 17527004 DOI: 10.1507/endocrj.k07-009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
This study was conducted to evaluate the long term effect of castration on the prostate gland proliferation, extracellular matrix remodeling and angiogenesis. Prostate gland proliferation was assessed by immunolocalization of proliferating cell nuclear antigen (PCNA). The expression level of vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-beta) and metaloprotenase-13 (MMP-13) by the prostate gland were assessed by immunohistochemistry and quantitative real-time PCR. The expression of the above mentioned parameters by the prostate gland of mature intact dogs were compared to that of castrated dogs six months post-castration. The results showed that castration induced a remarkable atrophy of the prostate gland which was associated with a highly significant decrease in the PCNA proliferation index. Although TGF-beta protein was immunolocalized to the epithelial and stroma cells of the prostate gland from both intact and castrated dogs, castration induced a significant up-regulation of TGF-beta mRNA expression. VEGF mRNA expression and its encoded protein immunolocalization were decreased significantly by the prostate gland from castrated dogs as compared to that of intact dogs. Castration, on the other hand, resulted in no significant change in MMP-13 mRNA expression despite an effect on its cellular immunolocalization which appeared to be localized to the epithelial and stromal cells of the prostate gland from castrated dogs as compared to epithelial cells of the prostate gland from intact dogs. These results indicated that castration-induced prostate gland regression continued to exert a potent suppressive effect on prostate gland proliferation which might be mediated by the elevated level of TGF-beta. Moreover, the low expression level of VEGF might reflect a reduced blood flow demand by the regressed and growth-dormant prostate after castration.
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Affiliation(s)
- Falah Shidaifat
- Department of Basic Veterinary Medical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid, Jordan
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Mercader M, Sengupta S, Bodner BK, Manecke RG, Cosar EF, Moser MT, Ballman KV, Wojcik EM, Kwon ED. Early effects of pharmacological androgen deprivation in human prostate cancer. BJU Int 2007; 99:60-7. [PMID: 17227493 DOI: 10.1111/j.1464-410x.2007.06538.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVES To assess the early histological effects of pharmacological androgen deprivation (AD), which have been assessed only over longer periods, as surgical castration leads rapidly to diminished cell proliferation and enhanced cell death within the prostate. PATIENTS AND METHODS With Institutional Review Board approval, 35 patients were randomly assigned (seven in each group) to receive 0, 7, 14, 21 and 28 days of AD (flutamide, 250 mg orally three times/day, and one injection with leuprolide acetate 7.5 mg) before radical prostatectomy. The surgical specimens were assessed by conventional histology and immunohistochemistry, while macroarray analysis and quantitative real-time polymerase chain reaction (QRT-PCR) were used to examine gene expression. RESULTS There were morphological changes within the prostatic tissues as early as 7 days after initiating AD, similar to the response to castration. There was tumour cell vacuolization indicating cellular injury, glandular atrophy and mononuclear cell infiltration as prominent and progressive effects but, by contrast with castration studies, there were no changes in epithelial proliferation or apoptosis. Macroarray analysis, validated by QRT-PCR and immunohistochemistry, showed up-regulation of numerous and potentially counter-effective genes involved in the cell cycle and apoptosis. CONCLUSIONS Pharmacological AD induces significant involution within prostatic tissues over 7-28 days, but allows the persistence of some viable tumour cells capable of proliferation.
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Affiliation(s)
- Maria Mercader
- Department of Urology, Mayo Clinic, Rochester, MN 55905, USA
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Ohlson N, Bergh A, Stattin P, Wikström P. Castration-induced epithelial cell death in human prostate tissue is related to locally reduced IGF-1 levels. Prostate 2007; 67:32-40. [PMID: 16998819 DOI: 10.1002/pros.20480] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Castration rapidly reduces stroma insulin-like growth factor (IGF)-1 synthesis and action in mouse prostate epithelium. We explore if similar changes are of importance for castration-induced prostate regression in humans. METHODS Epithelial and surrounding stroma cells were micro-dissected from patient biopsies obtained before and shortly after castration. IGF-1 mRNA levels were quantified by RT-PCR and related to epithelial apoptosis and IGF-1, IGF-1 receptor, and androgen receptor (AR) immunoreactivity. RESULTS IGF-1 mRNA was principally produced in the stroma and IGF-R1 in the epithelium. Stroma IGF-1 mRNA levels were significantly decreased after castration in non-malignant but not malignant tissue. Lack of stroma IGF-1 reduction after castration was associated with low stroma AR expression before therapy. Reduction of IGF-1 mRNA levels in the tumor stroma and/or epithelium was associated with epithelial apoptosis after therapy. CONCLUSIONS Low AR expression and maintained stroma IGF-1 synthesis may result in limited tumor cell death after castration therapy.
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Affiliation(s)
- Nina Ohlson
- Department of Medical Biosciences, Pathology, Umeå University, Umeå, Sweden
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Hammarsten P, Halin S, Wikstöm P, Henriksson R, Rudolfsson SH, Bergh A. Inhibitory Effects of Castration in an Orthotopic Model of Androgen-Independent Prostate Cancer Can Be Mimicked and Enhanced by Angiogenesis Inhibition. Clin Cancer Res 2006; 12:7431-6. [PMID: 17189416 DOI: 10.1158/1078-0432.ccr-06-1895] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Today, the most important treatment of advanced prostate cancer is castration; unfortunately, however, the long-term effect of this therapy is insufficient. Recent studies suggest that castration-induced prostate involution could be caused by primary effects in the prostate vasculature; therefore, we examined if antivascular treatments could mimic the effects of castration. EXPERIMENTAL DESIGN Androgen-independent AT-1 prostate cancer cells were grown inside the ventral prostate in adult rats. Tumor-bearing animals were treated with an inhibitor of vascular endothelial growth factor receptor 2 and epidermal growth factor receptor signaling, N-(4-bromo-2-fluorophenyl)-6-methoxy-7-[(1-methylpiperidin-4-yl)methoxy]quinazolin-4-amine (ZD6474, AstraZeneca, Södertälje, Sweden), and short-term effects (after 3 days) were compared with those induced by castration. RESULTS Castration caused decreased vascular density in the normal tissue surrounding the tumor and consequently increased tumor hypoxia and apoptosis, and moderately decreased tumor growth. ZD6474 treatment resulted in decreased tumor vascular density accompanied by increased tumor hypoxia, apoptosis, and decreased tumor growth, suggesting that castration and antiangiogenic therapy work through similar mechanisms. Interestingly, castration or ZD6474 alone worked by reducing vascular density in the surrounding normal tissue and ZD6474 also in the tumor. Combined treatment with castration + ZD6474 was more effective than castration and ZD6474 alone in inducing tumor hypoxia, apoptosis, necrosis, and decreasing tumor vascular density. CONCLUSION These findings show that a drug that targets the vasculature in the tumor and in the surrounding ventral prostate lobe could mimic and even enhance the effects of castration. Our present findings thus suggest that castration + ZD6474 could be a particularly effective way to treat prostate tumors.
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Affiliation(s)
- Peter Hammarsten
- Department of Medical Biosciences, Umeå University, Umeå, Sweden
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Ohlson N, Bergh A, Nygren K, Stattin P, Wikström P. The Magnitude of Early Castration-Induced Primary Tumour Regression in Prostate Cancer Does Not Predict Clinical Outcome. Eur Urol 2006; 49:675-83. [PMID: 16387414 DOI: 10.1016/j.eururo.2005.10.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Accepted: 10/04/2005] [Indexed: 11/19/2022]
Abstract
INTRODUCTION This study was designed to test whether early castration-induced short-term cellular changes in primary prostate tumours could predict clinical outcome in advanced disease. PATIENTS AND METHODS Biopsies from 83 patients obtained before and within two weeks after surgical castration were investigated. Tumour epithelial cell apoptosis, proliferation, and prostate specific antigen (PSA) levels were quantified using immunohistochemistry, laser capture micro-dissection, and real time RT-PCR. Cellular effects were related to changes in serum PSA levels and clinical outcome. RESULTS Decreased proliferation and PSA mRNA levels, and increased apoptosis were observed in most tumours. These early cellular responses were not correlated to each other and did not predict serum PSA response or cancer-specific survival. A nadir PSA level below 1 ng/ml predicted a longer cancer-specific survival after castration therapy. CONCLUSION Castration therapy causes primary tumour regression in most patients with advanced prostate cancer, but these primary tumour effects are not predictive for systemic disease control. Studies of early changes in metastases during hormonal therapy will probably give more predictive information for clinical outcome than further studies in primary tumours.
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Affiliation(s)
- Nina Ohlson
- Department of Medical Biosciences, Pathology, Umeå University, Umeå, Sweden.
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Donohue JF, Hayne D, Karnik U, Thomas DR, Foster MC. Randomized, placebo-controlled trial showing that finasteride reduces prostatic vascularity rapidly within 2 weeks. BJU Int 2005; 96:1319-22. [PMID: 16287453 DOI: 10.1111/j.1464-410x.2005.05849.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To measure expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in the prostates of men after transurethral resection of the prostate (TURP) following 2 weeks of treatment with finasteride. PATIENTS AND METHODS Sixty-four men scheduled to undergo TURP were randomized to receive 5 mg of finasteride or placebo daily for 2 weeks before surgery. Sections of prostatic urothelium were stained for VEGF expression and for CD31 to assess MVD. Ten consecutive, non-overlapping high-power fields were analysed in a blinded fashion. RESULTS In all, 31 men received finasteride and 33 placebo; the groups were similar in patient age, resected prostate weight, preoperative catheterization, prostate-specific antigen level, aspirin use, spinal anaesthesia and postoperative diagnosis of prostate cancer. The mean (95% confidence interval) MVD was significantly lower in the finasteride group (60, 55-65) than in the placebo group (71, 64-78; P < 0.01). Similarly, the mean expression of VEGF was significantly lower in the finasteride group (47, 43-52 vs 61, 54-67; P < 0.001) CONCLUSION Finasteride inhibits angiogenic growth factors leading to reduced vascularity, and this is the basis of its action in reducing haematuria of prostatic origin. The present study shows that finasteride influences the prostatic microvasculature after only 2 weeks exposure.
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Affiliation(s)
- John F Donohue
- Department of Urology, Good Hope Hospital, Birmingham, UK.
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Aslan G, Cimen S, Yorukoglu K, Tuna B, Sonmez D, Mungan U, Celebi I. Vascular endothelial growth factor expression in untreated and androgen-deprived patients with prostate cancer. Pathol Res Pract 2005; 201:593-8. [PMID: 16259113 DOI: 10.1016/j.prp.2005.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The aim of the study was to investigate immunohistochemically the expression of vascular endothelial growth factor (VEGF) in untreated and androgen-deprived patients with prostate cancer. The study included 20 patients with prostate cancer who had undergone transurethral prostatectomy due to infravesical obstruction. All patients had been receiving androgen deprivation therapy for at least 3 months. Transurethral prostatectomy specimens were examined for VEGF expression after androgen deprivation, and the biopsy samples of the same patients were used for the evaluation of VEGF expression before androgen deprivation. VEGF expression was analyzed using immunohistochemistry. Staining patterns determined by the staining scores were compared before and after treatment. The correlation of VEGF expression with PSA, Gleason score, and the percent change in PSA after treatment was also investigated. Eligible biopsy specimens were available in 15 of the 20 patients, allowing for the evaluation of VEGF expression before treatment. All prostate cancer specimens were positive. VEGF was localized mainly in the cytoplasm or on the membrane of carcinoma cells. Staining was strong in 86.7% of patients before androgen deprivation. Heterogeneous staining (strong in 25%, moderate in 35%, and weak in 40%) was observed after treatment. Staining scores were significantly higher in patients before androgen deprivation and showed a significant decrease after androgen deprivation (p = 0.007). Tumor staining correlated with Gleason score. No significant correlation was determined between VEGF expression and pre-treatment PSA and percent change of PSA after treatment. Immunohistochemical results indicate that VEGF expression is downregulated by androgen deprivation therapy. VEGF may be a potential target for therapeutic intervention in prostate cancer.
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Affiliation(s)
- Guven Aslan
- Department of Urology, Dokuz Eylul University School of Medicine, Izmir, Turkey.
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May KML, Vogt A, Bachas LG, Anderson KW. Vascular endothelial growth factor as a biomarker for the early detection of cancer using a whole cell-based biosensor. Anal Bioanal Chem 2005; 382:1010-6. [PMID: 15928947 DOI: 10.1007/s00216-005-3224-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 03/16/2005] [Accepted: 03/24/2005] [Indexed: 11/29/2022]
Abstract
Vascular endothelial growth factor (VEGF) is a cytokine and endothelial cell (EC) mitogen that has been studied for its role in angiogenesis of malignant tumors. Elevated quantities of VEGF in the serum and plasma of patients have been correlated with the presence of cancer and metastasis. Since VEGF induces hyperpermeability of EC monolayers, this protein can be detected in vitro with a whole cell-based biosensor. This biosensor consists of a confluent monolayer of human umbilical vein endothelial cells (HUVECs) attached to a cellulose triacetate (CTA) membrane of an ion-selective electrode (ISE). Previous studies regarding this biosensor have shown that when the biosensor was exposed to a model toxin, such as histamine, the response of the biosensor served as an indirect measurement of the presence of histamine. Similarly, the biosensor responds to the presence of VEGF, but is much more sensitive because VEGF is known to be 50,000-fold more potent than histamine when inducing EC hyperpermeability. The ISE response increased with increasing VEGF concentration. Since lower concentrations required more exposure time, the detection limit was established as a function of exposure time (2-10 h). The practical applicability of the biosensor was also established with cultured human melanoma cells WM793 (nonmetastatic) and 1205LU (metastatic). The resultant change in the potential values revealed significant production of VEGF from the 1205LU cells. A VEGF ELISA was performed to confirm the VEGF concentration in each sample. The biosensor closely predicted the concentrations determined through the ELISA. These results support the use of a cell-based ISE as a quick screening method for the presence of VEGF.
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Affiliation(s)
- Kimberly M L May
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
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Ohlson N, Wikström P, Stattin P, Bergh A. Cell proliferation and apoptosis in prostate tumors and adjacent non-malignant prostate tissue in patients at different time-points after castration treatment. Prostate 2005; 62:307-15. [PMID: 15389788 DOI: 10.1002/pros.20139] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Androgen ablation is the standard treatment for advanced prostate cancer but the short-term cellular effects are largely unknown. METHODS Sextant prostate biopsies were taken from 77 prostate cancer patients before and 1-10 days after castration treatment. Apoptosis, cell proliferation, and morphology were studied in malignant and non-malignant tissue, using stereological and immunohistochemical methods. RESULTS Epithelial cell proliferation was significantly decreased both in non-malignant and malignant epithelium already 1 day after therapy. It remained low until day 7, but increased thereafter in the remaining non-malignant epithelial cells and in some tumors. Epithelial cell apoptosis was significantly increased during the first week and then returned to basal levels. The maximal apoptotic indexes, seven- and two-times the intact levels in the non-malignant and malignant glands, respectively, were found at days 3-4 or even earlier in the tumors. Signs of tumor shrinkage such as glandular collapse and decreased tumor cell size were observed from day 3 in most tumors. DISCUSSION The present study shows that the magnitude and kinetics of the response to castration in the normal human prostate is very similar to the response previously described in rodents. We also demonstrate that most human prostate tumors rapidly respond to castration indicating the need for further evaluation of when and how to best monitor the effects of hormone ablation therapy in prostate cancer patients.
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Affiliation(s)
- Nina Ohlson
- Department of Medical Biosciences, Pathology, and Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
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16
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Gustavsson H, Welén K, Damber JE. Transition of an androgen-dependent human prostate cancer cell line into an androgen-independent subline is associated with increased angiogenesis. Prostate 2005; 62:364-73. [PMID: 15389782 DOI: 10.1002/pros.20145] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Androgen-independent prostate cancer is today an incurable disease, but increased understanding of the mechanisms for the transition into an androgen-independent state may increase the possibilities for more efficient strategies in the future. METHODS An androgen-independent subline, LNCaP-19, to the androgen-dependent prostate cancer cell line LNCaP was developed in vitro under standard culture conditions. The characteristics of LNCaP-19 regarding androgen responsiveness, PSA, and VEGF secretion was studied in vitro. The growth in vivo and the microvessel density (MVD) of the tumors were studied after inoculation in nude mice. RESULTS LNCaP-19 grows equally well in dextran-charcoal stripped FBS (DCC-FBS) as in normal FBS, and rapidly gives rise to tumors in both intact and castrated mice, indicating a true androgen-independent growth. The PSA secretion from LNCaP-19 cells was lower than from LNCaP cells, while the VEGF level was comparable to the secretion from LNCaP cells without androgen stimulation. The MVD was increased in the LNCaP-19 tumors, and the vessels also displayed a changed morphology with exclusively small microvessels without lumen. CONCLUSIONS LNCaP-19 shows characteristics resembling those of androgen-independent prostate cancer. An increased MVD and changed vessel morphology in the tumor, makes it an interesting model system for studies regarding angiogenesis in the context of the acquisition of androgen independence.
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Affiliation(s)
- Heléne Gustavsson
- Department of Urology, Institution for the Surgical Sciences, Göteborg University, Göteborg, Sweden
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Wikström P, Lindahl C, Bergh A. Characterization of the autochthonous transgenic adenocarcinoma of the mouse prostate (TRAMP) as a model to study effects of castration therapy. Prostate 2005; 62:148-64. [PMID: 15389804 DOI: 10.1002/pros.20123] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND In order to learn more about short- and long-term effects of castration therapy, relevant model systems for prostate cancer are required. In this study, we examined whether the transgenic adenocarcinoma of the mouse prostate (TRAMP) tumor response to castration in C57BL/6 mice mimics that seen in patients. METHODS Transgenic animals were examined before and 3 days after castration, at the ages of 17, 24, and 36 weeks. Moreover, 24-weeks old animals were castrated and followed for 6 months. Immunohistochemistry (IHC) and stereology were used to evaluate epithelial cell proliferation and death, blood vessel volume, androgen receptor (AR) expression, and transgenic expression of SV40 large T. RESULTS Cancer developed preferentially in the dorso-lateral prostate lobe. Tumor burden and incidence of metastases increased with age. The majority of tumors were well differentiated, while poorly differentiated, large tumors and macroscopic metastases developed in 8% of the animals. Well and moderately differentiated tumors responded to castration with cessation of proliferation and induction of apoptosis. Poorly differentiated tumors and metastases did not respond. Castration prevented local tumor growth for at least 6 months in 82% of the cases. Although, 45% of the treated animals developed wide-spread metastatic disease suggesting that castration may enhance growth of distant metastases. CONCLUSIONS The C57Bl/6 TRAMP tumor in several ways mimics how prostate cancer in patients responds to castration both in the short and long term, but some differences may also exist. This model can preferably be used to elucidate how this treatment works, and to test how it can be improved by additional therapies.
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Affiliation(s)
- Pernilla Wikström
- Department of Medical Bioscience, Pathology, Umeå University, 091 85 Umeå, Sweden.
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Bostwick DG, Burke HB, Djakiew D, Euling S, Ho SM, Landolph J, Morrison H, Sonawane B, Shifflett T, Waters DJ, Timms B. Human prostate cancer risk factors. Cancer 2004; 101:2371-490. [PMID: 15495199 DOI: 10.1002/cncr.20408] [Citation(s) in RCA: 383] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Prostate cancer has the highest prevalence of any nonskin cancer in the human body, with similar likelihood of neoplastic foci found within the prostates of men around the world regardless of diet, occupation, lifestyle, or other factors. Essentially all men with circulating androgens will develop microscopic prostate cancer if they live long enough. This review is a contemporary and comprehensive, literature-based analysis of the putative risk factors for human prostate cancer, and the results were presented at a multidisciplinary consensus conference held in Crystal City, Virginia, in the fall of 2002. The objectives were to evaluate known environmental factors and mechanisms of prostatic carcinogenesis and to identify existing data gaps and future research needs. The review is divided into four sections, including 1) epidemiology (endogenous factors [family history, hormones, race, aging and oxidative stress] and exogenous factors [diet, environmental agents, occupation and other factors, including lifestyle factors]); 2) animal and cell culture models for prediction of human risk (rodent models, transgenic models, mouse reconstitution models, severe combined immunodeficiency syndrome mouse models, canine models, xenograft models, and cell culture models); 3) biomarkers in prostate cancer, most of which have been tested only as predictive factors for patient outcome after treatment rather than as risk factors; and 4) genotoxic and nongenotoxic mechanisms of carcinogenesis. The authors conclude that most of the data regarding risk relies, of necessity, on epidemiologic studies, but animal and cell culture models offer promise in confirming some important findings. The current understanding of biomarkers of disease and risk factors is limited. An understanding of the risk factors for prostate cancer has practical importance for public health research and policy, genetic and nutritional education and chemoprevention, and prevention strategies.
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Letsch M, Schally AV, Busto R, Bajo AM, Varga JL. Growth hormone-releasing hormone (GHRH) antagonists inhibit the proliferation of androgen-dependent and -independent prostate cancers. Proc Natl Acad Sci U S A 2003; 100:1250-5. [PMID: 12538852 PMCID: PMC298759 DOI: 10.1073/pnas.0337496100] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The antiproliferative effects of an antagonist of growth hormone-releasing hormone (GHRH) JV-1-38 were evaluated in nude mice bearing s.c. xenografts of LNCaP and MDA-PCa-2b human androgen-sensitive and DU-145 androgen-independent prostate cancers. In the androgen-sensitive models, JV-1-38 greatly potentiated the antitumor effect of androgen deprivation induced by surgical castration, but was ineffective when given alone. Thus, in castrated animals bearing MDA-PCa-2b cancers, the administration of JV-1-38 for 35 days virtually arrested tumor growth (94% inhibition vs. intact control, P < 0.01; and 75% vs. castrated control, P < 0.05). The growth of LNCaP tumors was also powerfully suppressed by JV-1-38 combined with castration (83% inhibition vs. intact control, P < 0.01; and 68% vs. castrated control, P < 0.05). However, in androgen-independent DU-145 cancers, JV-1-38 alone could inhibit tumor growth by 57% (P < 0.05) after 45 days. In animals bearing MDA-PCa-2b and LNCaP tumors, the reduction in serum prostate-specific antigen levels, after therapy with JV-1-38, paralleled the decrease in tumor volume. Inhibition of MDA-PCa-2b and DU-145 cancers was associated with the reduction in the expression of mRNA and protein levels of vascular endothelial growth factor. The mRNA expression for GHRH receptor splice variants was found in all these models of prostate cancer. Our results demonstrate that GHRH antagonists inhibit androgen-independent prostate cancers and, after combination with androgen deprivation, also androgen-sensitive tumors. Thus, the therapy with GHRH antagonist could be considered for the management of both androgen-dependent or -independent prostate cancers.
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Affiliation(s)
- Markus Letsch
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center, and Section of Experimental Medicine, Department of Medicine, Tulane University School of Medicine, New Orleans, LA 70112, USA
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