Androgen deprivation induces human prostate epithelial neuroendocrine differentiation of androgen-sensitive LNCaP cells

Neuroendocrine (NE) cells are the minor cell populations in normal prostate epithelial compartments. During prostate carcinogenesis, the number of NE cells in malignant lesions increases, correlating with its tumorigenicity and hormone-refractory growth. It is thus proposed that cancerous NE cells promote prostate cancer (PCa) cell progression and its androgen-independent proliferation, although the origin of the cancerous NE cells is not clear. To investigate the role of cancerous NE cells in prostate carcinogenesis, we characterized three NE subclone cell lines–NE-1.3, NE-1.8 and NE-1.9, which were transdifferentiated from androgen-sensitive human PCa LNCaP cells by culturing in an androgen-depleted environment, resembling clinical androgen-ablation therapy. These subclone cells acquire many features of NE cells seen in clinical prostate carcinomas, for example exhibiting a neuronal morphology and expressing multiple NE markers, including neuron-specific enolase, chromogranin B, neurotensin, parathyroid hormone-related peptide, and to a lesser degree for chromogranin A, while lacking androgen receptor (AR) or prostate specific antigen (PSA) expression. These cells represent terminally differentiated stable cells because after 3 months of re-culturing in a medium containing androgenic activity, they still retained the NE phenotype and expressed NE markers. Despite these NE cells having a slow growth rate, they readily developed xenograft tumors. Furthermore, media conditioned by these NE cells exhibited a stimulatory effect on proliferation and PSA secretion by LNCaP cells in androgen-deprived conditions. Additionally, we found that receptor protein tyrosine phosphatase α plays a role in upregulating multiple NE markers and acquiring the NE phenotype. These NE cells thus represent cancerous NE cells and could serve as a useful cell model system for investigating the role of cancerous NE cells in hormone-refractory proliferation of PCa cells.

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Xanthine Oxidase/Dehydrogenase Activity as a Source of Oxidative Stress in Prostate Cancer Tissue

Diagnostics ◽

10.3390/diagnostics10090668 ◽

2020 ◽

Vol 10 (9) ◽

pp. 668

Author(s):

Andrej Veljković ◽

Jovan Hadži-Dokić ◽

Dušan Sokolović ◽

Dragoslav Bašić ◽

Ljubinka Veličković-Janković ◽

...

Keyword(s):

Oxidative Stress ◽

Prostate Cancer ◽

Xanthine Oxidase ◽

Dehydrogenase Activity ◽

Tumor Tissue ◽

Specific Antigen ◽

Cancer Tissue ◽

Prostate Carcinogenesis ◽

Promising Treatment

Prostate cancer (PC) is one of the most frequent malignancies. Better biomarkers are constantly wanted, such as those which can help with the prediction of cancer behavior. What is also needed is a marker which may serve as a possible therapeutic target. Oxidative stress (OS), which is a hallmark of cancer, is included in the pathogenesis and progression of PC. We have conducted the present study to determine whether xanthine oxidase/dehydrogenase activity is the source of OS in prostate tissue. We have also determined the concentration of TBA-reactive substances (TBARS) and advanced oxidation protein products (AOPP), as well as the activity of catalase. Xanthine oxidase (XO) activity is significantly higher (p < 0.001) in tumor tissue when compared to the control healthy tissue. The concentration of TBARS (p < 0.001) and AOPP (p < 0.05) are also higher in tumor tissue. Catalase has raised its activity (p < 0.05) versus the control. There is also a strong correlation between XO activity and prostate-specific antigen (PSA) levels in the serum. These results indicate a significant role of XO activity in OS in prostate carcinogenesis, and it could be a possible theranostic biomarker, which can be important for a better understanding of the disease, its evolution, and prognosis. A promising treatment may be using XO inhibitors such as allopurinol as adjuvant therapy.

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Alteration of Androgen Receptor Protein Stability by Triptolide in LNCaP Cells

Medicina ◽

10.3390/medicina54030039 ◽

2018 ◽

Vol 54 (3) ◽

pp. 39

Author(s):

Wei Li ◽

Bi-De Liu ◽

Kai Liao ◽

Yong Liu ◽

Zi-Jin Wan ◽

...

Keyword(s):

Protein Synthesis ◽

Androgen Receptor ◽

Protein Stability ◽

Protein Level ◽

Receptor Protein ◽

Calpain Inhibitor ◽

Lncap Cells ◽

Western Blot Assay ◽

The Stability

Background and Objective: Although triptolide was effective for prostate cancer (PCa), the mechanism is still unclear. Androgen receptor (AR) plays a large role in the development and progression of PCa, even after castration. The present study aimed at investigating the effects of triptolide on AR protein stability and the possible mechanism. Materials and Methods: By blocking protein synthesis with cycloheximide (CHX), the effect of triptolide on AR protein stability was investigated with western blot assay. The potential role of calpains in triptolide reduced AR protein stability was investigated with calpain inhibitor and Ca2+ chelator. Results: Triptolide down-regulated AR protein level when protein synthesis was blocked by CHX, demonstrating the decrease of AR protein stability. The AR protein level was restored when the cells were co-treated with triptolide and calpain inhibitor or Ca2+ chelator, indicating the important role of calpains. Conclusions: The results indicate that triptolide can activate calpain via promoting intracellular Ca2+ accumulation, and thus decrease the stability of AR protein, subsequently resulting in the breakdown of the AR protein in LNCaP cells. This work provides an experimental basis and evidence to elucidate the anti-PCa mechanisms of triptolide.

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The Molecular Effects of Sulforaphane and Capsaicin on Metabolism upon Androgen and Tip60 Activation of Androgen Receptor

International Journal of Molecular Sciences ◽

10.3390/ijms20215384 ◽

2019 ◽

Vol 20 (21) ◽

pp. 5384 ◽

Cited By ~ 3

Author(s):

Catalina Carrasco-Pozo ◽

Kah Ni Tan ◽

Tayner Rodriguez ◽

Vicky M. Avery

Keyword(s):

Androgen Receptor ◽

Bioactive Compounds ◽

Cell Metabolism ◽

Prostate Gland ◽

Specific Antigen ◽

Protective Role ◽

Metabolic Reprogramming ◽

Lncap Cells ◽

Pathway Activation

Androgen receptor (AR) stimulators, such as androgen and Tip60, play a pivotal role in prostatic carcinogenesis as androgen receptor signaling is critical for the growth and transformation of the prostate gland. Moreover, androgen and Tip60 promotes HIF-1α activation, involved in metabolic reprogramming by increasing glycolysis, a hallmark in cancer initiation and development. In this study we evaluated the effect of androgen and Tip60 stimulus in AR pathway activation and HIF-1α stabilization, in terms of proliferation and cell metabolism in androgen-sensitive LNCaP cells. The protective role of the bioactive compounds sulforaphane and capsaicin against the effect of these stimuli leading to pro-carcinogenic features was also addressed. Sulforaphane and capsaicin decreased nuclear AR, prostate specific antigen and Bcl-XL levels, and cell proliferation induced by androgen and Tip60 in LNCaP cells. These bioactive compounds prevented the increase in glycolysis, hexokinase and pyruvate kinase activity, and reduced HIF-1α stabilization induced by androgen and Tip60 in LNCaP cells. The protective role of sulforaphane and capsaicin on prostate cancer may rely on mechanisms involving the inhibition of Tip60, AR and HIF-1α effects.

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Leupaxin, a Novel Coactivator of the Androgen Receptor, Is Expressed in Prostate Cancer and Plays a Role in Adhesion and Invasion of Prostate Carcinoma Cells

Molecular Endocrinology ◽

10.1210/me.2006-0546 ◽

2008 ◽

Vol 22 (7) ◽

pp. 1606-1621 ◽

Cited By ~ 22

Author(s):

Silke Kaulfuss ◽

Michal Grzmil ◽

Bernhard Hemmerlein ◽

Paul Thelen ◽

Stefan Schweyer ◽

...

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Nuclear Export ◽

Mutational Analysis ◽

Specific Antigen ◽

High Rate ◽

Dependent Manner ◽

Lncap Cells ◽

Normal Prostate ◽

Progression Marker

Abstract In the present study, we demonstrate that leupaxin mRNA is overexpressed in prostate cancer (PCa) as compared with normal prostate tissue by using cDNA arrays and quantitative RT-PCR analyses. Moderate to strong expression of leupaxin protein was detected in approximately 22% of the PCa tissue sections analyzed, and leupaxin expression intensities were found to be significantly correlated with Gleason patterns/scores. In addition, different leupaxin expression levels were observed in PCa cell lines, and at the subcellular level, leupaxin was usually localized in focal adhesion sites. Furthermore, mutational analysis and transfection experiments of LNCaP cells using different green fluorescent protein-leupaxin constructs demonstrated that leupaxin contains functional nuclear export signals in its LD3 and LD4 motifs, thus shuttling between the cytoplasm and the nucleus. We could also demonstrate for the first time that leupaxin interacts with the androgen receptor in a ligand-dependent manner and serves as a transcriptional activator of this hormone receptor in PCa cells. Down-regulation of leupaxin expression using RNA interference in LNCaP cells resulted in a high rate of morphological changes, detachment, spontaneous apoptosis, and a reduction of prostate-specific antigen secretion. In contrast, knockdown of leupaxin expression in androgen-independent PC-3 and DU 145 cells induced a significant decrease of both the invasive capacity and motility. Our results therefore indicate that leupaxin could serve as a potential progression marker for a subset of PCa and may represent a novel coactivator of the androgen receptor. Leupaxin could function as a putative target for therapeutic interventions of a subset of advanced PCa.

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Estrogen receptor β2 and β5 are associated with poor prognosis in prostate cancer, and promote cancer cell migration and invasion

Endocrine Related Cancer ◽

10.1677/erc-09-0294 ◽

2010 ◽

Vol 17 (3) ◽

pp. 675-689 ◽

Cited By ~ 86

Author(s):

Yuet-Kin Leung ◽

Hung-Ming Lam ◽

Shulin Wu ◽

Dan Song ◽

Linda Levin ◽

...

Keyword(s):

Prostate Cancer ◽

Cell Migration ◽

Specific Antigen ◽

Ectopic Expression ◽

Migration And Invasion ◽

Independent Prognostic Marker ◽

Prostate Carcinogenesis ◽

Kaplan Meier ◽

Cell Invasiveness

Estrogens play a pivotal role in the development and progression of prostate cancer (PCa). Their actions are mediated by estrogen receptors (ERs), particularly ERβ in the prostate epithelium. With the discovery of ERβ isoforms, data from previous studies that focused principally on the wild-type ERβ (ERβ1) may not be adequate in explaining the still controversial role of ERβ(s) in prostate carcinogenesis. In this study, using newly generated isoform-specific antibodies, immunohistochemistry (IHC) was performed on a tumor microarray comprised of 144 specimens. IHC results were correlated with pathological and clinical follow-up data to delineate the distinct roles of ERβ1, ERβ2, and ERβ5 in PCa. ERβ2 was commonly found in the cytoplasm and was the most abundant isoform followed by ERβ1 localized predominantly in the nucleus, and ERβ5 was primarily located in the cytoplasm. Logistic regression analyses demonstrated that nuclear ERβ2 (nERβ2) is an independent prognostic marker for prostate specific antigen (PSA) failure and postoperative metastasis (POM). In a Kaplan–Meier analysis, the combined expression of both nERβ2 and cytoplasmic ERβ5 identified a group of patients with the shortest POM-free survival. Cox proportional hazard models revealed that nERβ2 predicted shorter time to POM. In concordance with IHC data, stable, ectopic expression of ERβ2 or ERβ5 enhanced PCa cell invasiveness but only PCa cells expressing ERβ5 exhibited augmented cell migration. This is the first study to uncover a metastasis-promoting role of ERβ2 and ERβ5 in PCa, and show that the two isoforms, singularly and conjointly, have prognostic values for PCa progression. These findings may aid future clinical management of PCa.

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Deregulated expression of selected histone methylases and demethylases in prostate carcinoma

Endocrine Related Cancer ◽

10.1530/erc-13-0375 ◽

2013 ◽

Vol 21 (1) ◽

pp. 51-61 ◽

Cited By ~ 40

Author(s):

Filipa Quintela Vieira ◽

Pedro Costa-Pinheiro ◽

João Ramalho-Carvalho ◽

Andreia Pereira ◽

Francisco Duarte Menezes ◽

...

Keyword(s):

Epigenetic Alterations ◽

Normal Prostate ◽

Tissue Samples ◽

Histone Methyltransferases ◽

Expression Levels ◽

Prostate Carcinogenesis ◽

Localized Disease ◽

Aggressive Tumors ◽

Therapeutic Decision Making

Prostate cancer (PCa), a leading cause of cancer-related morbidity and mortality, arises through the acquisition of genetic and epigenetic alterations. Deregulation of histone methyltransferases (HMTs) or demethylases (HDMs) has been associated with PCa development and progression. However, the precise influence of altered HMTs or HDMs expression and respective histone marks in PCa onset and progression remains largely unknown. To clarify the role of HMTs and HDMs in prostate carcinogenesis, expression levels of 37 HMTs and 20 HDMs were assessed in normal prostate and PCa tissue samples by RT-qPCR.SMYD3,SUV39H2,PRMT6,KDM5A, andKDM6Awere upregulated, whereasKMT2A-E (MLL1-5)andKDM4Bwere downregulated in PCa, compared with normal prostate tissues. Remarkably,PRMT6was the histone modifier that best discriminated normal from tumorous tissue samples. Interestingly,EZH2andSMYD3expression levels significantly correlated with less differentiated and more aggressive tumors. Remarkably,SMYD3expression levels were of independent prognostic value for the prediction of disease-specific survival of PCa patients with clinically localized disease submitted to radical prostatectomy. We concluded that expression profiling of HMTs and HDMs, especiallySMYD3, might be of clinical usefulness for the assessment of PCa patients and assist in pre-therapeutic decision-making.

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Prevention of Hormone-Related Cancers: Prostate Cancer

Journal of Clinical Oncology ◽

10.1200/jco.2005.08.027 ◽

2005 ◽

Vol 23 (2) ◽

pp. 368-377 ◽

Cited By ~ 42

Author(s):

Howard L. Parnes ◽

Ian M. Thompson ◽

Leslie G. Ford

Keyword(s):

Prostate Cancer ◽

Germ Line ◽

Disease Risk ◽

Cancer Susceptibility ◽

Specific Antigen ◽

Normal Prostate ◽

Prostate Development ◽

Prostate Carcinogenesis ◽

Prostate Cancer Prevention ◽

High Prevalence

Androgens are known to play an important role in normal prostate development, benign prostatic hyperplasia, established prostate cancer, and in prostate carcinogenesis. However, despite convincing experimental and clinical evidence, the epidemiologic data correlating sex steroid levels with disease risk is inconsistent. More recent work has focused on studies of polymorphisms in germ-line DNA in an effort to develop polygenic models of prostate cancer susceptibility and prognosis. Such models have the potential to aid in the selection of men for specific chemopreventive interventions and to help determine which men with localized prostate cancer are most likely to benefit from aggressive therapy. In this review, we will provide a brief summary of androgen metabolic pathways followed by an assessment of the epidemiology literature addressing the relationship between androgens and prostate cancer. Finally, we will address the two major questions that have arisen in response to the recently published results from the Prostate Cancer Prevention Trial: Who are the best candidates for finasteride chemoprevention, and what are the clinical implications of the high prevalence of prostate cancer that was detected in men with prostate-specific antigen levels in the so-called “normal” range?

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Androgens Suppress EZH2 Expression Via Retinoblastoma (RB) and p130-Dependent Pathways: A Potential Mechanism of Androgen-Refractory Progression of Prostate Cancer

Endocrinology ◽

10.1210/en.2010-0436 ◽

2010 ◽

Vol 151 (11) ◽

pp. 5136-5145 ◽

Cited By ~ 55

Author(s):

Laura R. Bohrer ◽

Shuai Chen ◽

Timothy C. Hallstrom ◽

Haojie Huang

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Target Genes ◽

Retinoblastoma Protein ◽

Lncap Cells ◽

Normal Prostate ◽

Androgen Ablation ◽

Androgen Treatment ◽

Polycomb Protein ◽

Ezh2 Expression

Androgens and the androgen receptor are important for both normal prostate development and progression of prostate cancer (PCa). However, the underlying mechanisms are not fully understood. The Polycomb protein enhancer of zeste homolog 2 (EZH2) functions as an epigenetic gene silencer and plays a role in oncogenesis by promoting cell proliferation and invasion. EZH2 has been implicated in human PCa progression, because its expression is often elevated in hormone-refractory PCa. Here, we demonstrated that expression of EZH2 is lower in androgen-sensitive LNCaP PCa cells compared with Rf and C4-2 cells, two androgen-refractory sublines that are derived from LNCaP cells. Androgen ablation by castration increased the level of EZH2 proteins in LNCaP xenografts in mice. In contrast, treatment of LNCaP cells in culture with the synthetic androgen methyltrieolone (R1881) at doses of 1 nm or higher suppressed EZH2 expression. Moreover, our data suggest that androgen repression of EZH2 requires a functional androgen receptor and this effect is mediated through the retinoblastoma protein and its related protein p130. We further showed that androgen treatment not only increases expression of EZH2 target genes DAB2IP and E-cadherin but also affects LNCaP cell migration. Our results reveal that androgens function as an epigenetic regulator in prostatic cells by repression of EZH2 expression through the retinoblastoma protein and p130-dependent pathways. Our findings also suggest that blockade of EZH2 derepression during androgen deprivation therapy may represent an effective tactic for the treatment of androgen-refractory PCa.

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Examining the Role of Neoadjuvant Androgen Deprivation in Patients Undergoing Prostate Brachytherapy

Journal of Clinical Oncology ◽

10.1200/jco.2000.18.6.1187 ◽

2000 ◽

Vol 18 (6) ◽

pp. 1187-1192 ◽

Cited By ~ 100

Author(s):

Louis Potters ◽

Taryn Torre ◽

Richard Ashley ◽

Steven Leibel

Keyword(s):

Prostate Cancer ◽

Specific Antigen ◽

Androgen Deprivation ◽

Matched Pair ◽

Prostate Brachytherapy ◽

Absolute Increase ◽

Androgen Ablation ◽

Matched Pair Analysis ◽

Pair Analysis

PURPOSE: To assess the role of neoadjuvant androgen deprivation (NAAD) and transperineal interstitial permanent prostate brachytherapy (TIPPB) using a matched-pair analysis selected from a large cohort of patients undergoing TIPPB. PATIENTS AND METHODS: Six hundred twelve consecutive patients with clinically confined prostate cancer were treated between June 1992, and January 1997, with permanent ultrasound-guided TIPPB with either palladium-103 or iodine-125 as monotherapy or combined with external radiation. Patients with prostate glands ≥ 60 g underwent treatment with NAAD before TIPPB to reduce the prostate volume (n = 163). The median duration of NAAD was 3.4 months before TIPPB (range, 1 to 8 months). To assess the benefit of NAAD, a matched-pair analysis was performed. The American Society of Therapeutic Radiology and Oncology Consensus Group definition of prostate-specific antigen (PSA) relapse-free survival (RFS) was used with the added caveat of an absolute increase of ≥ 1.0 ng/mL. Differences in pretreatment PSA, Gleason scores, and stage were analyzed by Kaplan-Meier curves and the log-rank test. RESULTS: Two hundred sixty-three patients were matched, with a median follow-up duration of 46 months (range, 24 to 76 months). The actuarial 5-year PSA-RFS rate for all 263 patients is 86.5%. The 5-year PSA-RFS rate for patients treated with NAAD and TIPPB was 87.1% compared with 86.9% for those treated with TIPPB only (P = .935). Subgroup analysis by Gleason score groupings, pretreatment PSA, or stage of disease failed to identify any factors for which androgen ablation was beneficial. CONCLUSION: We were unable to identify any improvement with the addition of NAAD to TIPPB in patients with localized prostate cancer in this retrospective matched-pair analysis. Furthermore, there was no subset for which the addition of NAAD was found to be beneficial. Clarification of the role and duration of NAAD in patients with early-stage prostate cancer will require prospective data.

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