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Sjöblom L, Saramäki O, Annala M, Leinonen K, Nättinen J, Tolonen T, Wahlfors T, Nykter M, Bova GS, Schleutker J, Tammela TLJ, Lilja H, Visakorpi T. Microseminoprotein-Beta Expression in Different Stages of Prostate Cancer. PLoS One 2016; 11:e0150241. [PMID: 26939004 PMCID: PMC4777373 DOI: 10.1371/journal.pone.0150241] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/02/2016] [Indexed: 11/18/2022] Open
Abstract
Microseminoprotein-beta (MSMB, MSMB) is an abundant secretory protein contributed by the prostate, and is implicated as a prostate cancer (PC) biomarker based on observations of its lower expression in cancerous cells compared with benign prostate epithelium. However, as the current literature on MSMB is inconsistent, we assessed the expression of MSMB at the protein and mRNA levels in a comprehensive set of different clinical stages of PC. Immunohistochemistry using monoclonal and polyclonal antibodies against MSMB was used to study protein expression in tissue specimens representing prostatectomies (n = 261) and in diagnostic needle biopsies from patients treated with androgen deprivation therapy (ADT) (n = 100), and in locally recurrent castration-resistant PC (CRPC) (n = 105) and CRPC metastases (n = 113). The transcript levels of MSMB, nuclear receptor co-activator 4 (NCOA4) and MSMB-NCOA4 fusion were examined by qRT-PCR in prostatectomy samples and by RNA-sequencing in benign prostatic hyperplasia, PC, and CRPC samples. We also measured serum MSMB levels and genotyped the single nucleotide polymorphism rs10993994 using DNA from the blood of 369 PC patients and 903 controls. MSMB expression in PC (29% of prostatectomies and 21% of needle biopsies) was more frequent than in CRPC (9% of locally recurrent CRPCs and 9% of CRPC metastases) (p<0.0001). Detection of MSMB protein was inversely correlated with the Gleason score in prostatectomy specimens (p = 0.024). The read-through MSMB-NCOA4 transcript was detected at very low levels in PC. MSMB levels in serum were similar in cases of PC and controls but were significantly associated with PC risk when adjusted for age at diagnosis and levels of free or total PSA (p<0.001). Serum levels of MSMB in both PC patients and controls were significantly associated with the rs10993994 genotype (p<0.0001). In conclusion, decreased expression of MSMB parallels the clinical progression of PC and adjusted serum MSMB levels are associated with PC risk.
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Affiliation(s)
- Liisa Sjöblom
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland.,Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
| | - Outi Saramäki
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland.,Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
| | - Matti Annala
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - Katri Leinonen
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland.,Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
| | - Janika Nättinen
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - Teemu Tolonen
- Department of Pathology, Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
| | - Tiina Wahlfors
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - Matti Nykter
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - G Steven Bova
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - Johanna Schleutker
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland
| | - Teuvo L J Tammela
- Prostate Cancer Research Center, School of Medicine, University of Tampere, Tampere, Finland.,Department of Urology, Tampere University Hospital, Tampere, Finland
| | - Hans Lilja
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland.,Departments of Laboratory Medicine, Surgery, and Medicine, Memorial Sloan Kettering Cancer Center, New York, United States of America.,Nuffield Department of Surgical Sciences, University of Oxford, Oxford, United Kingdom.,Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Tapio Visakorpi
- Prostate Cancer Research Center, Institute of Biosciences and Medical Technology (BioMediTech), University of Tampere, Tampere, Finland.,Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
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Fokidis HB, Adomat HH, Kharmate G, Hosseini-Beheshti E, Guns ES, Soma KK. Regulation of local steroidogenesis in the brain and in prostate cancer: lessons learned from interdisciplinary collaboration. Front Neuroendocrinol 2015; 36:108-29. [PMID: 25223867 DOI: 10.1016/j.yfrne.2014.08.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 08/28/2014] [Accepted: 08/28/2014] [Indexed: 11/16/2022]
Abstract
Sex steroids play critical roles in the regulation of the brain and many other organs. Traditionally, researchers have focused on sex steroid signaling that involves travel from the gonads via the circulation to intracellular receptors in target tissues. This classic concept has been challenged, however, by the growing number of cases in which steroids are synthesized locally and act locally within diverse tissues. For example, the brain and prostate carcinoma were previously considered targets of gonadal sex steroids, but under certain circumstances, these tissues can upregulate their steroidogenic potential, particularly when circulating sex steroid concentrations are low. We review some of the similarities and differences between local sex steroid synthesis in the brain and prostate cancer. We also share five lessons that we have learned during the course of our interdisciplinary collaboration, which brought together neuroendocrinologists and cancer biologists. These lessons have important implications for future research in both fields.
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Affiliation(s)
- H Bobby Fokidis
- Department of Biology, Rollins College, Winter Park, FL 37289, USA; Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada.
| | - Hans H Adomat
- Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada
| | | | | | - Emma S Guns
- Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada; Department of Urological Sciences, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kiran K Soma
- Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Brain Research Centre, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
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3
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Pospisil P, Wang K, Al Aowad AF, Iyer LK, Adelstein SJ, Kassis AI. Computational Modeling and Experimental Evaluation of a Novel Prodrug for Targeting the Extracellular Space of Prostate Tumors. Cancer Res 2007; 67:2197-205. [PMID: 17332350 DOI: 10.1158/0008-5472.can-06-3309] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We are developing a noninvasive approach for targeting imaging and therapeutic radionuclides to prostate cancer. Our method, Enzyme-Mediated Cancer Imaging and Therapy (EMCIT), aims to use enzyme-dependent, site-specific, in vivo precipitation of a radioactive molecule within the extracellular space of solid tumors. Advanced methods for data mining of the literature, protein databases, and knowledge bases (IT. Omics LSGraph and Ingenuity Systems) identified prostatic acid phosphatase (PAP) as an enzyme overexpressed in prostate cancer and secreted in the extracellular space. Using AutoDock 3.0 software, the prodrug ammonium 2-(2'-phosphoryloxyphenyl)-6-iodo-4-(3H)-quinazolinone (IQ(2-P)) was docked in silico into the X-ray structure of PAP. The data indicate that IQ(2-P) docked into the PAP active site with a calculated inhibition constant (K(i)) more favorable than that of the PAP inhibitor alpha-benzylaminobenzylphosphonic acid. When (125)IQ(2-P), the radioiodinated form of the water-soluble prodrug, was incubated with PAP, rapid hydrolysis of the compound was observed as exemplified by formation of the water-insoluble 2-(2'-hydroxyphenyl)-6-[(125)I]iodo-4-(3H)-quinazolinone ((125)IQ(2-OH)). Similarly, the incubation of IQ(2-P) with human LNCaP, PC-3, and 22Rv1 prostate tumor cells resulted in the formation of large fluorescent IQ(2-OH) crystals. No hydrolysis was seen in the presence of normal human cells. Autoradiography of tumor cells incubated with (125)IQ(2-P) showed accumulation of radioactive grains ((125)IQ(2-OH)) around the cells. We anticipate that the EMCIT approach will enable the active in vivo entrapment of radioimaging and radiotherapeutic compounds within the extracellular spaces of primary prostate tumors and their metastases.
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Affiliation(s)
- Pavel Pospisil
- Department of Radiology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
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Loberg RD, St John LN, Day LL, Neeley CK, Pienta KJ. Development of the VCaP androgen-independent model of prostate cancer. Urol Oncol 2006; 24:161-8. [PMID: 16520280 PMCID: PMC1557359 DOI: 10.1016/j.urolonc.2005.11.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Prostate epithelial cell growth is dependent on the presence of androgens, and transition of prostate cancer to an androgen-independent phenotype results in a highly aggressive, currently incurable cancer. We have developed a new preclinical model of androgen-independent prostate cancer derived from the VCaP prostate cancer epithelial cell line. VCaP cells were subcutaneously implanted and serially passaged in castrated male severe combined immunodeficient mice. Androgen independence was confirmed by WST-1 (a tetrazolium salt) cell proliferation assay in the absence or presence of dihydrotesterone (1-100 nM). VCaP androgen-sensitive cells responded dose dependently to dihydrotesterone, whereas VCaP androgen-independent cells did not alter their proliferation in response to dihydrotesterone. Gene expression of androgen receptor, B-cell lymphoma-2, prostate cancer antigen 3, prostate acid phosphatase, 6 transmembrane epithelial antigen of the prostate, and survivin was determined by polymerase chain reaction amplification. B-cell lymphoma-2 expression was up regulated in the VCaP androgen-independent lines compared to the VCaP androgen-sensitive, suggesting a possible mechanism of androgen independence. Furthermore, tumor-associated angiogenesis was assessed by immunofluorescence confocal microscopy of CD31. VCaP androgen-independent tumors showed enhanced angiogenesis compared to VCaP androgen-sensitive tumors. These results illustrate the development of a novel model of prostate cancer androgen independence and provide a new system to study angiogenesis and the transition to androgen independence.
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Affiliation(s)
- Robert D Loberg
- Department of Urology, University of Michigan Urology Center, Ann Arbor, MI 48109-0946, USA.
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Nam RK, Reeves JR, Toi A, Dulude H, Trachtenberg J, Emami M, Daigneault L, Panchal C, Sugar L, Jewett MAS, Narod SA. A Novel Serum Marker, Total Prostate Secretory Protein of 94 Amino Acids, Improves Prostate Cancer Detection and Helps Identify High Grade Cancers at Diagnosis. J Urol 2006; 175:1291-7. [PMID: 16515983 DOI: 10.1016/s0022-5347(05)00695-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE New biomarkers for prostate cancer are needed. We determined whether a novel serum marker, total PSP94 can be used to accomplish these goals. MATERIALS AND METHODS We conducted a case-control study of 1,212 men with no previous history of prostate cancer and who underwent a prostate biopsy from 1998 to 2000 because of an increased PSA or an abnormal DRE. Serum PSP94 levels were assessed using a sandwich enzyme-linked immunosorbent assay technique. Cases were patients with prostate cancer, and controls were patients who had no evidence of cancer. Multivariate logistic regression analysis was used to determine whether or not PSP94 levels improved the predictive value for prostate cancer. RESULTS Of the 1,212 men 596 (49.2%) had cancer detected. The median PSP94 level was significantly lower among cases (2.60 ng/ml) than among controls (3.40 ng/ml, p <0.0001). The adjusted odds ratios for the presence of prostate cancer for patients with the lowest quartile of PSP94, compared to patients in the highest quartile was 2.70 (95% CI 1.8 - 4.0, p <0.0001). Among a subgroup of 649 men in whom PSA had a low predictive value (PSA less than 20 ng/ml, normal DRE and less than 70 years), 260 (40.1%) were found to have cancer. In this subgroup total PSP94 levels helped discriminate between patients with high grade disease (Gleason score 8 or more, median 1.90 ng/ml), moderate grade disease (Gleason score 7, median 2.34 ng/ml) and low grade disease (Gleason score 6 or less, median 2.60 ng/ml, p = 0.007). PSA and the FTPSA were not able to distinguish between patients with different grades in this group. CONCLUSIONS Patients with low total PSP94 levels had a high probability for having prostate cancer detected at biopsy. The total PSP94 level was able to help identify patients with high grade disease among a subset of patients in whom PSA and FTPSA are least informative.
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Affiliation(s)
- Robert K Nam
- Division of Urology, Sunnybrook and Women's College Health Sciences Centre and University Health Network, Toronto, Ontario, Canada.
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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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Lazure C, Villemure M, Gauthier D, Naudé RJ, Mbikay M. Characterization of ostrich (Struthio camelus) beta-microseminoprotein (MSP): identification of homologous sequences in EST databases and analysis of their evolution during speciation. Protein Sci 2001; 10:2207-18. [PMID: 11604528 PMCID: PMC2374068 DOI: 10.1110/ps.06501] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Beta-microseminoprotein, alternatively called prostatic secretory protein of 94 amino acids, is a hydrophilic, unglycosylated, small protein rich in conserved half-cystine residues. Originally found in human seminal plasma and prostatic fluids, its presence was later shown in numerous secretions and its homologs were described in many vertebrate species. These studies showed that this protein had rapidly evolved, but they failed to unambiguously identify its biological role. Here, we show that a protein isolated from ostrich pituitary gland is closely related to a similar one isolated from chicken serum and that the two are structurally related to the mammalian beta-microseminoprotein. The complete 90-amino acid sequence of the ostrich molecule was established through a combination of automated Edman degradation and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometric procedures, including postsource decay (PSD) and ladder sequencing analyses. This study documents for the first time that beta-microseminoprotein is present in aves. It is also the first report of a C-terminal amidated form for a member of this protein family and the first in which the disulfide linkages are established. Database searches using the herein-described amino acid sequence allowed identification of related proteins in numerous species such as cow, African clawed frog, zebrafish, and Japanese flounder. These small proteins show a strikingly high rate of amino acid substitutions, especially across phyla boundaries. Noticeably, no beta-microseminoprotein-related gene could be found in the recently completed fruit fly genome, indicating that if such a gene exists in arthropods, it must have extensively diverged from the vertebrate ones.
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Affiliation(s)
- C Lazure
- Laboratory of Structure and Metabolism of Neuropeptides, Institut de recherches cliniques de Montréal (affiliated with the University of Montréal), Montréal, Québec H2W 1R7, Canada.
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PSP94 EXPRESSION AFTER ANDROGEN DEPRIVATION THERAPY: A COMPARATIVE STUDY WITH PROSTATE SPECIFIC ANTIGEN IN BENIGN PROSTATE AND PROSTATE CANCER. J Urol 2000. [DOI: 10.1097/00005392-200011000-00108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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PSP94 EXPRESSION AFTER ANDROGEN DEPRIVATION THERAPY: A COMPARATIVE STUDY WITH PROSTATE SPECIFIC ANTIGEN IN BENIGN PROSTATE AND PROSTATE CANCER. J Urol 2000. [DOI: 10.1016/s0022-5347(05)67113-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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10
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Affiliation(s)
- T R Tennant
- Section of Urology, Department of Surgery, University of Chicago, Chicago, Illinois 60637, USA
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Abstract
Rapid advances in positional cloning studies have identified most of the genes on the human Y chromosome, thereby providing resources for studying the expression of its genes in prostate cancer. Using a semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) procedure, we had examined the expression of the Y chromosome genes in a panel of prostate samples diagnosed with benign prostatic hyperplasia (BPH), low and/or high grade carcinoma, and the prostatic cell line, LNCaP, stimulated by androgen treatment. Results from this expression analysis of 31 of the 33 genes, isolated so far from the Y chromosome, revealed three types of expression patterns: i) specific expression in other tissues (e.g., AMELY, BPY1, BPY2, CDY, and RBM); ii) ubiquitous expression among prostate and control testis samples, similar to those of house-keeping genes (e.g., ANT3, XE7,ASMTL, IL3RA, SYBL1, TRAMP, MIC2, DBY, RPS4Y, and SMCY); iii) differential expression in prostate and testis samples. The last group includes X-Y homologous (e.g., ZFY, PRKY, DFFRY, TB4Y, EIF1AY, and UTY) and Y-specific genes (e.g., SRY, TSPY, PRY, and XKRY). Androgen stimulation of the LNCaP cells resulted in up-regulation of PGPL, CSFR2A, IL3RA, TSPY, and IL9R and down regulation of SRY, ZFY, and DFFRY. The heterogeneous and differential expression patterns of the Y chromosome genes raise the possibility that some of these genes are either involved in or are affected by the oncogenic processes of the prostate. The up- and down-regulation of several Y chromosome genes by androgen suggest that they may play a role(s) in the hormonally stimulated proliferation of the responsive LNCaP cells.
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Affiliation(s)
- Y F Lau
- Division of Cell and Developmental Genetics, Department of Medicine, VA Medical Center, 111C5, University of California, San Francisco, San Francisco, California 94121, USA.
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Wu D, Guo Y, Chambers AF, Izawa JI, Chin JL, Xuan JW. Serum bound forms of PSP94 (prostate secretory protein of 94 amino acids) in prostate cancer patients. J Cell Biochem 1999; 76:71-83. [PMID: 10581002 DOI: 10.1002/(sici)1097-4644(20000101)76:1<71::aid-jcb8>3.0.co;2-b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
PSP94 (prostate secretory protein of 94 amino acids) was regarded as a possible prostate cancer marker, however, it has been controversial. All prior studies were designed to test the free form in serum using antibodies to PSP94. Results presented here demonstrate that PSP94 exists in prostate cancer patients in two forms, free and bound, and that the majority is present as serum bound complexes. This result was demonstrated by using both native and SDS-PAGE analyses of serum proteins from prostate cancer patients. Chromatographic separation of serum total proteins by a molecular sieve column generated two peaks (peak I and II), which were reactive with rabbit antiserum to human PSP94 in Western blot experiments. Peak I was eluted before the IgG fraction at a molecular weight larger than 150 kDa, and peak II appeared after serum albumin ( approximately 67 kDa) was eluted. By using a biotinylated PSP94 as an indicator of the free form of PSP94, we demonstrate that peak I contains serum PSP94-bound complexes and peak II is likely the free form of serum PSP94. Since the molecular weight of serum PSP94-bound complexes is close to IgG during molecular sieve separation, serum PSP94 complexes were further purified through two rounds of protein A column separation, followed by DEAE-ion exchange column chromatography. In vitro dissociation tests of the purified PSP94-bound complexes showed that the binding of serum PSP94-complexes is probably via disulfide bonds and is chemically stable. The results presented here indicate that serum PSP94-bound complexes must be considered in evaluating the clinical utility of PSP94 as a prostate cancer marker.
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Affiliation(s)
- D Wu
- Department of Surgery, University of Western Ontario, London, Ontario N6A 4G5, Canada
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13
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Chan PS, Chan LW, Xuan JW, Chin JL, Choi HL, Chan FL. In situ hybridization study of PSP94 (prostatic secretory protein of 94 amino acids) expression in human prostates. Prostate 1999; 41:99-109. [PMID: 10477906 DOI: 10.1002/(sici)1097-0045(19991001)41:2<99::aid-pros4>3.0.co;2-c] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The prostatic secretory protein of 94 amino acids (PSP94), also named beta-microseminoprotein, is one of the major proteins secreted by the human prostate. However, its value as a prognostic marker for prostate cancers is still under debate. The aim of the present study was to examine the expression pattern of this protein in fetal, pubertal, and aged human prostates. METHODS Nonisotopic in situ hybridization using a digoxigenin-labeled riboprobe for PSP94 and immunohistochemistry were used to demonstrate the expression of PSP94 in different regions or zones of fetal, pubertal, and adult human prostates. Its localization pattern was also compared with those of two other major secretory proteins, prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), by immunohistochemistry. RESULTS PSP94 mRNA and its protein were localized to the secretory epithelium of normal pubertal and adult human prostates. No hybridization signal and immunoreactivity of PSP94 were seen in fetal prostates at 6-7 months of gestation, whereas some glandular cells were positive to PSA and PAP immunostainings. In the adult prostates, PSP94 expression was intense in the acini in the peripheral zone, less intense in the transition zone, and variable in the central zone. Such a zonal expression pattern was more apparent in the pubertal prostates. However, no obvious differential expression pattern was observed in the immunohistochemistry of PAP and PSA, which showed a uniform staining of the secretory epithelia of the acini in all anatomic zones. The hybridization signals and immunoreactivity of PSP94 became reduced or lost in premalignant prostatic intraepithelial neoplastic lesions and different grades of prostatic carcinomas. CONCLUSIONS Fetal prostates at 6-7 months of gestation already synthesize PSA and PAP but not PSP94. The delayed expression of PSP94 appears to correlate with the development of the prostate gland. A differential expression pattern of PSP94 is demonstrated in different anatomical zones, showing that this protein is more expressed and synthesized in the acini in the peripheral zone than in the central and transition zones. However, such a zonal pattern is not seen in the immunohistochemistry of PSA and PAP. The present study also shows that PSP94 is downregulated in different grades of prostate cancers.
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Affiliation(s)
- P S Chan
- Department of Surgery, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong
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Kwong J, Chan FL, Jiang S, Guo Y, Imasato Y, Sakai H, Koropatnick J, Chin JL, Xuan JW. Differential expression of PSP94 in rat prostate lobes as demonstrated by an antibody against recombinant GST-PSP94. J Cell Biochem 1999. [DOI: 10.1002/(sici)1097-4644(19990901)74:3<406::aid-jcb9>3.0.co;2-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Garde SV, Basrur VS, Li L, Finkelman MA, Krishan A, Wellham L, Ben-Josef E, Haddad M, Taylor JD, Porter AT, Tang DG. Prostate secretory protein (PSP94) suppresses the growth of androgen-independent prostate cancer cell line (PC3) and xenografts by inducing apoptosis. Prostate 1999; 38:118-25. [PMID: 9973097 DOI: 10.1002/(sici)1097-0045(19990201)38:2<118::aid-pros5>3.0.co;2-g] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND PSP94 (prostate secretory protein of 94 aa; also called PIP), one of the predominant proteins secreted into the seminal fluid, was proposed as an independent diagnostic/prognostic marker for prostate cancers. It was also shown to inhibit rat prostate cancer growth. In this study, we investigated the effect of purified PSP94 on the growth of androgen-independent human prostate cancer cells (PC3) and its potential mechanism of action. METHODS AND RESULTS PSP94, in a dose- and time-dependent manner, inhibited the growth of PC3 cells. The protein demonstrated a stronger inhibitory effect on the colony-forming ability of PC3 cells in soft agar. A daily injection of PSP94 at 5 microg/kg/body weight resulted in a 50-60% inhibition in the growth of PC3 xenografts in athymic mice. PC3 cell growth inhibition by PSP94 resulted from cell death characteristic of morphological apoptosis, which was confirmed by dual fluorescence microscopy, electron microscopy, and DNA fragmentation assays. Mechanistic studies indicated that PSP94 enhanced the expression of proapoptotic protein Bax without affecting Bcl-2 levels. CONCLUSIONS This study suggests that PSP94 may represent a novel, apoptosis-based, antitumor agent applicable to the treatment of hormone-refractory human prostate cancers.
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Affiliation(s)
- S V Garde
- Procyon Biopharma, Inc., London, Ontario, Canada
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16
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Xuan JW, Kwong J, Chan FL, Ricci M, Imasato Y, Sakai H, Fong GH, Panchal C, Chin JL. cDNA, genomic cloning, and gene expression analysis of mouse PSP94 (prostate secretory protein of 94 amino acids). DNA Cell Biol 1999; 18:11-26. [PMID: 10025505 DOI: 10.1089/104454999315583] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The potential use of prostate secretory protein of 94 amino acids (PSP94) as a diagnostic biomarker or a therapeutic agent for prostate cancer has been reported. In order to establish an animal model to further elucidate on its biological role, we cloned the mouse PSP94 cDNA (approximately 500 bp) by reverse transcriptase-polymerase chain reaction (RT-PCR) and disclosed its genomic structure. The whole mouse PSP94 gene (approximately 23 kb) was amplified by long and accurate-PCR and also cloned by screening of a mouse embryo stem-cell genomic library. Computational and statistical analyses have demonstrated several highly conserved characteristics of PSP94 among different species. Comparison of PSP94 from human, two primates, pig, and rodents revealed that the most significant feature is that PSP94 is rich in cysteines (10% of the total sequence) and their positions are highly conserved. The three intron-four exon structure of the human PSP94 gene and the consensus sequence (....GT-intron-AG...) for mRNA splicing are also strongly conserved. A high divergence in cDNA sequence in the protein-coding region and also in the genomic sequence of PSP94 was also observed among these species. Comparing with alpha-globin, a typical evolutionally conserved gene, with the PSP94 gene, the rate of nonsynonymous changes per site per year (kN) is 2 to 6 times higher, indicating that PSP94 gene has been under far fewer evolutionary constraints than other genes and has a potential role as a species barrier in reproductive biology. In order to test this hypothesis, we investigated the gene expression of PSP94 and its tissue distribution in various rodent tissues by RT-PCR and in situ hybridization (ISH). Gene expression was found only in the prostate, suggesting that PSP94 is probably more tissue specific in the prostate of rodents than in mammals. The ISH analysis also revealed a prostate lobe-specific expression of the PSP94 gene in both mice and rats. It was strongly expressed in the lateral prostate, but the findings were negative in the dorsal and ventral lobe. Therefore, it is hypothesized that one of the primary functions of rodent PSP94, as a major prostate secretory protein, is related to reproductive biology.
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Affiliation(s)
- J W Xuan
- Department of Surgery, University of Western Ontario, London, Canada
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17
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Abstract
BACKGROUND Our objective was to investigate the presence of prostate specific antigen (PSA) and alpha-1-antichymotrypsin (ACT) mRNA and protein in prostate cancer cell lines, and the complexing characteristics of expressed PSA. METHODS RT-PCR, immunohistochemistry, and Western blots were employed. Trypsin treatment of PSA was performed to establish the possible presence of an activatable form of PSA. RESULTS ACT mRNA and protein were detected in LNCaP, PC-3, and DU 145 by RT-PCR and by immunohistochemistry, respectively. Only LNCaP cells were positive for PSA mRNA and protein. LNCaP expressed approximately 30% active PSA, approximately 40% putative zymogen form of PSA, and approximately 30% stably inactive PSA. CONCLUSIONS We have shown that the majority of PSA expressed by LNCaP cells is present in free, noncomplexed forms in the conditioned media. A portion (40%) can be activated by trypsin, while the rest is stably inactive PSA. LNCaP cells may serve as a source of the "unreactive" PSA present in prostate cancer patients' serum.
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Affiliation(s)
- E Corey
- Department of Urology, School of Medicine, University of Washington, Seattle 98195, USA.
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18
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Tsurusaki T, Koji T, Sakai H, Kanetake H, Nakane PK, Saito Y. Cellular expression of beta-microseminoprotein (beta-MSP) mRNA and its protein in untreated prostate cancer. Prostate 1998; 35:109-16. [PMID: 9568674 DOI: 10.1002/(sici)1097-0045(19980501)35:2<109::aid-pros4>3.0.co;2-e] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Previous studies have shown that beta-microseminoprotein (beta-MSP) may be used as a diagnostic marker for prostate cancer. However, the level of expression of beta-MSP in prostate cancer detected by immunohistochemistry (IHC) has varied from one study to another. METHODS We analyzed the expression of both beta-MSP mRNA and its protein in a large sample of prostate tumors from 104 patients with untreated prostate cancer, using both nonradioactive in situ hybridization (ISH) and IHC. RESULTS Our results showed that 72 and 96 of 104 specimens were negative for beta-MSP mRNA (69.2%) and beta-MSP (92.3%), respectively. Furthermore, a reduced expression of both beta-MSP mRNA and its protein was detected in all malignant epithelial tissues compared with benign epithelia. Not all malignant tissue samples negative for beta-MSP mRNA were negative for beta-MSP (6.7%), and vice versa (29.8%). Other tissue samples were either negative for both (62.5%) or positive for both (1.0%). CONCLUSIONS Our results showed a lower level of expression of beta-MSP in prostate cancer tissue, compared with benign prostate tissue. This phenomenon may be mainly due to the presence of reduced levels of beta-MSP mRNA.
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Affiliation(s)
- T Tsurusaki
- Department of Urology, Nagasaki University School of Medicine, Sakamoto, Japan.
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19
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Xuan JW, Wu D, Guo Y, Garde S, Baijal-Gupta M, Chin JL. Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (I) immuno-dominant and immuno-recessive area. J Cell Biochem 1997. [DOI: 10.1002/(sici)1097-4644(199705)65:2<172::aid-jcb4>3.0.co;2-r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (II) epitope mapping by monoclonal antibodies. J Cell Biochem 1997. [DOI: 10.1002/(sici)1097-4644(199705)65:2<186::aid-jcb5>3.0.co;2-q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Ma YL, Fujiyama C, Masaki Z, Sugihara H. Reconstruction of prostatic acinus-like structure from ventral and dorsolateral prostatic epithelial cells of the rat in three-dimensional collagen gel matrix culture. J Urol 1997; 157:1025-31. [PMID: 9072537 DOI: 10.1016/s0022-5347(01)65135-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE The study was carried out to reconstruct a prostatic acinus-like structure from prostatic epithelial cells in a new culture system which can provide a more physiological condition than conventional cell culture methods. MATERIALS AND METHODS Prostatic epithelial cells were isolated from ventral and dorsolateral prostates of the rat and were separately cultured in three-dimensional collagen gel matrix. The cultured cells were observed by photo-microscopy and transmission electron microscopy. Differentiation and proliferation of the cultured cells were examined by immunohistochemistry using PAP and PSA kits and a bromodeoxy-uridine (BrdU) kit. The cell area of acinus-like structures in the transverse sections was measured by computer with the Interaktive Bild-Analyse System. RESULTS Dissociated prostatic epithelial cells were organized into three-dimensional spherical or branching cellular aggregates in collagen gel matrix. Through cell proliferation and differentiation, the cellular aggregates formed prostatic acinus-like structures, which consisted of a small intercellular lumen enclosed by one layer of cuboidal epithelial cells. The epithelial cells were connected together by junctional complexes, had microvilli at the luminal surface, and the basal side was surrounded by a distinct basal lamina. In the lumina of acinus-like structures, secretory products were often found. CONCLUSIONS Prostatic acinus-like structures were reconstructed from dissociated prostatic epithelial cells in three-dimensional collagen gel matrix culture. The reconstructed acinus-like structures are similar to prostatic acini in vivo in structure and function. This three-dimensional collagen gel matrix culture model may provide a useful means for investigating prostatic diseases and influences that hormones and growth factors exert on prostatic epithelial cells.
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Affiliation(s)
- Y L Ma
- Department of Pathology, Saga Medical School, Japan
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22
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Reconstruction of Prostatic Acinus-Like Structure from Ventral and Dorsolateral Prostatic Epithelial Cells of the Rat in Three-Dimensional Collagen Gel Matrix Culture. J Urol 1997. [DOI: 10.1097/00005392-199703000-00100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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23
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Webber MM, Bello D, Quader S. Immortalized and tumorigenic adult human prostatic epithelial cell lines: characteristics and applications Part 2. Tumorigenic cell lines. Prostate 1997; 30:58-64. [PMID: 9018337 DOI: 10.1002/(sici)1097-0045(19970101)30:1<58::aid-pros9>3.0.co;2-h] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This is Part 2 of a three-part review and deals with tumorigenic cell lines. Several immortalized and malignant adult human prostatic epithelial cell lines have been recently developed. The three most widely used carcinoma cell lines-DU-145, PC-3, and LNCaP-developed between 1977 and 1980, have greatly contributed to our current understanding of prostate cancer. Before a cell line can be accepted as having prostatic epithelial origin, some basic characteristics must be established. Expression of specific cytokeratins but absence of desmin and factor VIII should be first determined to establish epithelial origin. Responsiveness to androgens and expression of androgen receptor and prostate-specific antigen should be examined under stringent culture conditions to establish prostatic epithelial origin. Response to growth factors and expression of their receptors facilitates further characterization of cell behavior. Cell lines immortalized by human papillomaviruses (HPVs) are of special interest because HPVs are involved in a variety of anogenital cancers and may also play a role in prostate carcinogenesis. Malignant transformation of HPV-18 immortalized cells with the ras oncogene provides cell systems for investigating the multistep process of carcinogenesis. Each cell line has some unique characteristics, whether it arose directly from a carcinoma or resulted from immortalization with Simian virus 40 (SV40) or HPV, or was transformed in vitro by oncogenes. Comparisons of these characteristics should facilitate elucidation of the mechanisms involved in the initiation, promotion, and progression of prostate cancer. These cell lines will further serve as useful models for investigating tumor progression, invasion, metastasis, new therapeutic strategies, drug resistance, and its reversal and chemoprevention. The nontumorigenic cell lines were discussed in Part 1 [1]. This review summarizes the characteristics of several currently available tumorigenic, adult human prostatic epithelial cell lines.
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Affiliation(s)
- M M Webber
- Department of Medicine, Michigan State University, East Lansing 48824-1312, USA
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24
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Grant ES, Batchelor KW, Habib FK. Androgen independence of primary epithelial cultures of the prostate is associated with a down-regulation of androgen receptor gene expression. Prostate 1996; 29:339-49. [PMID: 8977630 DOI: 10.1002/(sici)1097-0045(199612)29:6<339::aid-pros1>3.0.co;2-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Epithelial cells cultured from prostatic acini do not demonstrate significant (P > 0.05) growth response to the testosterone metabolite dihydrotestosterone (DHT) at concentrations of 0.001-10.0 nM. In addition, the nonsteroidal antiandrogen hydroxyflutamide (HO-F) does not influence primary epithelial cell proliferation in this concentration range. METHODS Northern blotting carried out with an androgen reception (AR)-specific cDNA probe indicated that the extent of AR gene expression in six unpassaged primary prostatic epithelial cell cultures was insufficient to elicit a detectable signal upon autoradiography. However, RT/PCR analysis of total RNA using two sets of intron-spanning androgen receptor (AR) primers demonstrates the presence of full-length receptor transcripts in two BPH-derived epithelial cell cultures (BPH1 and BPH2) as well as a carcinoma-derived culture (CaP1). RESULTS AR-positive LNCaP cells transfected with the AR reporter plasmid pMMTV/SPAP exhibit significant increases (P < 0.05) in SPAP production upon treatment with DHT. pMMTV/SPAP-transfected primary epithelial cells exhibit no such response when pulsed with either androgen or anti-androgen. CONCLUSIONS These results indicate that the lack of significant AR gene expression underlies the androgen independence of primary prostatic epithelial cell cultures.
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MESH Headings
- Androgen Antagonists/pharmacology
- Androgens/pharmacology
- Androgens/physiology
- Base Sequence
- Blotting, Northern
- Cell Division/drug effects
- Cell Division/physiology
- DNA, Neoplasm/analysis
- DNA, Neoplasm/chemistry
- DNA, Neoplasm/genetics
- Dihydrotestosterone/pharmacology
- Dose-Response Relationship, Drug
- Down-Regulation/drug effects
- Down-Regulation/physiology
- Epithelium/chemistry
- Epithelium/drug effects
- Epithelium/pathology
- Flutamide/analogs & derivatives
- Flutamide/pharmacology
- Gene Expression Regulation, Neoplastic/physiology
- Humans
- Male
- Molecular Sequence Data
- Polymerase Chain Reaction
- Prostatic Neoplasms/chemistry
- Prostatic Neoplasms/pathology
- Prostatic Neoplasms/physiopathology
- RNA, Messenger/analysis
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- Receptors, Androgen/analysis
- Receptors, Androgen/genetics
- Receptors, Androgen/physiology
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- E S Grant
- Department of Surgery/Urology, University of Edinburgh, U.K
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25
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Xuan JW, Wu D, Guo Y, Fraser JE, Chin JL. Recombinant PSP94 (prostate secretory protein of 94 amino acids) demonstrates similar linear epitope structure as natural PSP94 protein. J Cell Biochem 1996. [DOI: 10.1002/(sici)1097-4644(199610)63:1<61::aid-jcb5>3.0.co;2-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Xuan JW, Wu D, Guo Y, Fraser JE, Chin JL. Recombinant PSP94 (prostate secretory protein of 94 amino acids) demonstrates similar linear epitope structure as natural PSP94 protein. J Cell Biochem 1996; 63:61-73. [PMID: 8891904 DOI: 10.1002/(sici)1097-4644(199610)63:1%3c61::aid-jcb5%3e3.0.co;2-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PSP94 has the potential to be a useful diagnostic marker and therapeutic agent in prostate cancer. Recently, different immunoassay systems for quantitative analysis of PSP94 in clinical samples have been developed, but the epitope structure of PSP94 protein has not been elucidated. In this study, we report an Escherichia coli expression system for recombinant GST-PSP94 fusion protein. GST-PSP94 contains antigenic determinants similar to natural PSP94 protein (determined both by Western blotting experiments and by ELISA) and can be used to study the structure of natural PSP94 antigen. Since GST-PSP94 was expressed in E. coli and purification involved a denaturing process, we propose that the epitope structure of PSP94 is linear and largely dependent on the primary amino acid sequence, rather than conformational structure. This hypothesis was supported by reciprocal competition in ELISA among natural, GST-PSP94 fusion protein, and purified recombinant PSP94 protein. The results demonstrate that the various forms of PSP94 can compete with each other in binding to rabbit PSP94 polyclonal antibody, although the natural PSP94 has a slightly higher affinity. When natural and recombinant PSP94 protein were denatured in vitro with urea and alkali, no effect on the binding to antibody was found. The epitope activity of natural PSP94 was also shown to be resistant to the treatment of detergent and reducing agent. The location of one of the linear epitopes recognized by the PSP94 antibody was determined to be in the N-terminus by using two synthetic peptides representing N- and C-terminal sequences. Competitive ELISA between the N-terminal peptide and PSP94 protein indicate that both natural and GST-PSP94 have similar immunoactive N-termini.
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Affiliation(s)
- J W Xuan
- Department of Surgery, University of Western Ontario, Canada.
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27
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Dai JL, Maiorino CA, Gkonos PJ, Burnstein KL. Androgenic up-regulation of androgen receptor cDNA expression in androgen-independent prostate cancer cells. Steroids 1996; 61:531-9. [PMID: 8883219 DOI: 10.1016/s0039-128x(96)00086-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The expression of the androgen receptor (AR) gene is regulated by androgens. Although androgens down-regulate AR mRNA in most cell lines and tissues, including the prostate, up-regulation occurs in some tissues. Androgen-mediated reduction in AR mRNA is reproduced in COS1 cells and in the androgen-sensitive human prostate cancer cell line LNCaP when each expresses the AR cDNA. We have previously established that the AR cDNA contains the requisite sequences for this down-regulation. Here we shown that androgen promoted up-regulation of AR mRNA in two androgen-independent human prostate cancer cell lines, PC3 and DU145, when each was transfected with a human AR cDNA. This effect was due to the AR cDNA and not to the heterologous promoter driving AR expression. In addition to up-regulation of AR mRNA, androgen induced comparable increases in AR protein levels in PC3 cells stably expressing an AR cDNA (PC3/AR). Up-regulation of AR in PC3/AR cells was accompanied by failure of these cells to undergo desensitization or inactivation of AR following prolonged (96 h) androgen administration, whereas the same conditions resulted in desensitization of AR transactivation in LNCaP cells and in CVl cells that stably express the AR cDNA. Androgen treatment of PC3/AR cells resulted in induction of an androgen-regulated reporter gene (MMTV-CAT) as well as the native prostate-specific antigen gene, which is silent in untransfected PC3 but is androgen up-regulated in LNCaP and in the prostate. These results suggest that ectopic expression of AR in androgen-independent prostate cancer cell lines establishes both typical and atypical androgenic responses in a target gene-specific manner. Androgenic up-regulation of AR cDNA expression may be due to distinct signaling mechanisms that influence androgen action in androgen-independent prostate cancer cells.
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MESH Headings
- Adenocarcinoma/drug therapy
- Adenocarcinoma/genetics
- Adenocarcinoma/pathology
- Androgens/pharmacology
- Animals
- Cells, Cultured
- Chloramphenicol O-Acetyltransferase/drug effects
- Chloramphenicol O-Acetyltransferase/genetics
- Chloramphenicol O-Acetyltransferase/metabolism
- Cytomegalovirus/genetics
- DNA, Complementary/biosynthesis
- Gene Expression Regulation, Neoplastic/drug effects
- Genes, Reporter
- Genetic Vectors/genetics
- Haplorhini
- Homeostasis
- Humans
- Kidney/cytology
- Kidney/drug effects
- Kidney/metabolism
- Male
- Mammary Tumor Virus, Mouse/genetics
- Promoter Regions, Genetic
- Prostate-Specific Antigen/drug effects
- Prostate-Specific Antigen/genetics
- Prostate-Specific Antigen/metabolism
- Prostatic Neoplasms/drug therapy
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/pathology
- RNA, Messenger/biosynthesis
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Transfection
- Tumor Cells, Cultured
- Up-Regulation/genetics
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Affiliation(s)
- J L Dai
- Department of Molecular and Cellular Pharmacology, University of Miami School of Medicine, FL 33101, USA
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