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1.
Fr J Urol ; 34(9): 102675, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38969304

ABSTRACT

OBJECTIVE: Information on bladder cancer (BC) according to the risk scoring for recurrence or progression in a general population is scarce despite its clinical relevance. The objective was to describe the characteristics of incident BC in a general population, with a focus on the initial management of high-risk non-muscle invasive BC (HR-NMIBC). MATERIALS: BC incident in 2011-2012 recorded in a population-based cancer registry were studied. Data was extracted from medical files. NMIBC were classified according to potential risk for recurrence/progression. Individual and tumor characteristics of incident BC were described. Incidence, initial management and survival (12/31/2021) of HR-NMIBC were assessed. RESULTS: Among 538 BC cases, 380 were NMIBC [119 low (22.1%), 163 intermediate (30.3%), 98 high (18.2%) risk] and 147 (27.3%) were MIBC. HR-NMIBC diagnostic and therapeutic management [imaging, re-TUR, multidisciplinary team meetings (MDT) assessment, specific treatment] revealed discrepancies with guidelines recommendations. Seventy-two out of 98 cases were assessed in an MDT with a median time from diagnosis of 18days [first quartile: 12-third quartile: 32]. Globally, treatment agreed with MDT decisions. Intravesical instillation was the most common treatment (n=56) but 27 HR-NMIBC did not receive specific treatment after TUR. Five and 10years overall survival was 52% [42-63] and 41% [31-51], respectively. Five years net survival was 63% [47-75]. CONCLUSIONS: Despite National cancer plans aiming to improve care giving and despite the severity of HR-NMIBC, guideline-recommended patterns of care were underused in this region. This may deserve attention to identify obstacles to guideline adoption to try to improve BC patient care and survival.

2.
Int J Qual Health Care ; 36(2)2024 May 18.
Article in English | MEDLINE | ID: mdl-38722033

ABSTRACT

Bladder cancer (BC) is a common malignancy in Europe and North America. Among BCs, muscle-invasive BCs (MIBCs) are distinguished, as they require aggressive treatment due to their spreading potential and poor prognosis. Despite its clinical relevance, little information on MIBC in a general population setting is available. This study aims to report practice patterns and survival outcomes for MIBC patients in a general population setting. MIBCs among BC incidence in 2011 and 2012 recorded in a French population-based cancer registry (810 000 inhabitants) were included in the study. Data were extracted from the medical files. Individual, tumour-related characteristics and initial management including diagnostic tools, multidisciplinary team meeting (MDT) assessment, and treatment delivered were described. Cystectomy, chemoradiation, radiotherapy, and chemotherapy were considered as specific treatments. Matching between MDT decision and the treatment provided was detailed. Management practices were discussed according to the guideline's recommendations. Overall survival (using the Kaplan-Meier method) and net survival (using the Pohar-Perme estimator) were calculated. Among 538 incident BC cases, 147 (27.3%) were MIBCs. Diagnostic practices displayed a relevant locoregional assessment of BC. Almost all cases (n = 136, 92.5%) were assessed during an uro-oncological MDT with a median time from diagnosis of 18 days (first quartile:12-third quartile:32). Discrepancies appeared between MDT decisions and treatments delivered: 71 out of 86 subjects received the recommended cystectomy or chemoradiation (with or without neoadjuvant chemotherapy); 6 out of 11 had the recommended radio- or chemotherapy; and 9 patients did not undergo any specific treatment despite the MDT decision. Cystectomy was the most common treatment performed; the time to surgery appeared consistent with the guideline's recommendations. Forty people only received supportive care. Still, the 5-year overall and net survival was poor, with 19% (13-26) and 22% (14-31), respectively. The 5-year net survival was 35% (23-48) for people who underwent curative-intent treatments. MIBC management remains challenging even for cases assessed during an MDT. Many people did not undergo any specific treatment. Prognosis was poor even when curative-intent therapies were delivered. Efforts to reduce exposure to risk factors such as tobacco smoking and occupational exposures must be maintained.


Subject(s)
Cystectomy , Practice Patterns, Physicians' , Urinary Bladder Neoplasms , Humans , Urinary Bladder Neoplasms/therapy , Urinary Bladder Neoplasms/mortality , Male , Female , Aged , Middle Aged , Practice Patterns, Physicians'/statistics & numerical data , Aged, 80 and over , France/epidemiology , Neoplasm Invasiveness , Registries
3.
Sci Rep ; 10(1): 19651, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33184390

ABSTRACT

Urinary incontinence of idiopathic nature is a common complication of bladder cancer, yet, the mechanisms underlying changes in bladder contractility associated with cancer are not known. Here by using tensiometry on detrusor smooth muscle (DSM) strips from normal rats and rats with bladder cancer induced by known urothelial carcinogen, N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), we show that bladder cancer is associated with considerable changes in DSM contractility. These changes include: (1) decrease in the amplitude and frequency of spontaneous contractions, consistent with the decline of luminal pressures during filling, and detrusor underactivity; (2) diminution of parasympathetic DSM stimulation mainly at the expense of m-cholinergic excitatory transmission, suggestive of difficulty in bladder emptying and weakening of urine stream; (3) strengthening of TRPV1-dependent afferent limb of micturition reflex and TRPV1-mediated local contractility, promoting urge incontinence; (4) attenuation of stretch-dependent, TRPV4-mediated spontaneous contractility leading to overflow incontinence. These changes are consistent with the symptomatic of bladder dysfunction in bladder cancer patients. Considering that BBN-induced urothelial lesions in rodents largely resemble human urothelial lesions at least in their morphology, our studies establish for the first time underlying reasons for bladder dysfunction in bladder cancer.


Subject(s)
Muscle Contraction , TRPV Cation Channels/metabolism , Urinary Bladder Neoplasms/physiopathology , Urinary Bladder/physiopathology , Urinary Incontinence/etiology , Animals , Butylhydroxybutylnitrosamine/toxicity , Disease Models, Animal , Male , Rats , Rats, Wistar , Urinary Bladder/drug effects , Urinary Bladder/metabolism , Urinary Bladder Neoplasms/chemically induced , Urinary Bladder Neoplasms/metabolism , Urinary Incontinence/metabolism , Urinary Incontinence/pathology
4.
iScience ; 23(7): 101263, 2020 Jul 24.
Article in English | MEDLINE | ID: mdl-32585596

ABSTRACT

Mitochondria are important cell death checkpoints, and mitochondrial Ca2+ overload is considered as a potent apoptotic intrinsic pathway inducer. Here, we report that this Ca2+ apoptosis link is largely ineffective in inducing cell-death just by itself and required a concomitant inhibition of autophagy to counteract its pro-survival action. In such condition, an acute mitochondrial stress revealed by a DRP1-mediated mitochondrial dynamic remodeling is observed concomitantly with mitochondrial depolarization, release of cytochrome c, and efficient apoptosis induction. We also uncover that mitochondrial Ca2+ status modulates the function of autophagy as a sensitizer for chemotherapies. This priming mediated by mitochondrial Ca2+ overload and inhibition of autophagy sensitizes many cancer cells types to different chemotherapies with independent mechanisms of action. Collectively, our results redefine an important cell signaling pathway, uncovering new combined therapies for the treatment of diseases associated with mitochondrial Ca2+ homeostasis disorders such as cancer.

5.
Urol Oncol ; 38(11): 847.e9-847.e16, 2020 11.
Article in English | MEDLINE | ID: mdl-32466877

ABSTRACT

OBJECTIVE: To validate a nomogram predicting lymph node invasion (LNI) in prostate cancer patients undergoing radical prostatectomy taking into consideration multiparametric-magnetic resonance imaging (mp-MRI) parameters and targeted biopsies in a western European cohort. PATIENTS AND METHODS: A total of 473 men diagnosed by targeted biopsies, using software-based MRI-ultrasound image fusion system, and operated by radical prostatectomy with extended pelvic lymph node dissection across 11 Europeans centers between 2012 and 2019 were identified. Area under the curve of the receiver operator characteristic curve, calibration plot and decision curve analysis were used to evaluated the performance of the model. RESULTS: Overall, 56 (11.8%) patients had LNI on final pathologic examination with a median (IQR) of 13 (9-18) resected nodes. Significant differences (all P < 0.05) were found between patients with and without LNI in terms of preoperative PSA, clinical stage at DRE and mp-MRI, maximum diameter of the index lesion, PI-RADS score, Grade Group on systematic and targeted biopsies, total number of dissected lymph nodes, final pathologic staging and Grade Group. External validation of the prediction model showed a good accuracy with an area under the curve calculated as 0.8 (CI 95% 0.75-0.86). Graphic analysis of calibration plot and decision curve analysis showed a slight underestimation for predictive probability for LNI between 3% and 22% and a high net benefit. A cut-off at 7% was associated with a risk of missing LNI in 2.6%, avoiding unnecessary surgeries in 55.9%. CONCLUSIONS: We report an external validation of the nomogram predicting LNI in patients treated with extended pelvic lymph node dissection in a western European cohort and a cut-off at 7% seems appropriate.


Subject(s)
Lymphatic Metastasis/pathology , Nomograms , Prostatic Neoplasms/pathology , Aged , Europe , Humans , Image-Guided Biopsy , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Invasiveness , Prognosis , Retrospective Studies , Risk Assessment
7.
Mol Carcinog ; 56(8): 1851-1867, 2017 08.
Article in English | MEDLINE | ID: mdl-28277613

ABSTRACT

Previous studies showed the effects of resveratrol (RES) on several cancer cells, including prostate cancer (PCa) cell apoptosis without taking into consideration the impact of the tumor microenvironment (TME). The TME is composed of cancer cells, endothelial cells, blood cells, and cancer-associated fibroblasts (CAF), the main source of growth factors. The latter cells might modify in the TME the impact of RES on tumor cells via secreted factors. Recent data clearly show the impact of CAF on cancer cells apoptosis resistance via secreted factors. However, the effects of RES on PCa CAF have not been studied so far. We have investigated here for the first time the effects of RES on the physiology of PCa CAF in the context of TME. Using a prostate cancer CAF cell line and primary cultures of CAF from prostate cancers, we show that RES activates the N-terminal mutated Transient Receptor Potential Ankyrin 1 (TRPA1) channel leading to an increase in intracellular calcium concentration and the expression and secretion of growth factors (HGF and VEGF) without inducing apoptosis in these cells. Interestingly, in the present work, we also show that when the prostate cancer cells were co-cultured with CAF, the RES-induced cancer cell apoptosis was reduced by 40%, an apoptosis reduction canceled in the presence of the TRPA1 channel inhibitors. The present work highlights CAF TRPA1 ion channels as a target for RES and the importance of the channel in the epithelial-stromal crosstalk in the TME leading to resistance to the RES-induced apoptosis.


Subject(s)
Anticarcinogenic Agents/pharmacology , Antioxidants/pharmacology , Calcium Channels/metabolism , Cancer-Associated Fibroblasts/drug effects , Nerve Tissue Proteins/metabolism , Prostate/drug effects , Prostatic Neoplasms/drug therapy , Stilbenes/pharmacology , Transient Receptor Potential Channels/metabolism , Amino Acid Sequence , Apoptosis/drug effects , Calcium/metabolism , Calcium Channels/analysis , Calcium Channels/genetics , Cancer-Associated Fibroblasts/metabolism , Cancer-Associated Fibroblasts/pathology , Cell Line, Tumor , Humans , Male , Mutation , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/genetics , Prostate/metabolism , Prostate/pathology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Resveratrol , TRPA1 Cation Channel , Transient Receptor Potential Channels/analysis , Transient Receptor Potential Channels/genetics , Tumor Microenvironment/drug effects
8.
J Endourol ; 31(5): 538-544, 2017 05.
Article in English | MEDLINE | ID: mdl-28326794

ABSTRACT

OBJECTIVES: Confocal laser endomicroscopy (CLE) uses a low-energy laser light source to obtain microscopic histology images of bladder tissue exposed to a fluorescent dye. To evaluate the feasibility of using CLE with two fluorophores: fluorescein (FLUO) and hexylaminolevulinate (HAL) to determine histologic and cytologic bladder cancer criteria. METHODS: Patients eligible for HAL-photodynamic diagnosis-assisted transurethral resection of bladder tumor were included. The procedures were performed with the patient under regional or general anesthesia (60-90 minutes) after bladder instillation of HAL (50 mL, 8 mmol/L; Hexvix®; Ipsen, France). Resected tissue was examined ex vivo using CLE either with Cellvizio® system (CVI) single laser (488 nm) or with Cellvizio Dual system (CVII) double laser (488, 660 nm). RESULTS: Twenty-one patients were included, 12 examined by CVI and 9 by CVII. Sample examination on CVI after HAL-CLE-only histologic analysis was not possible because HAL is mostly cytoplasmic and gives poor details on cellular architecture. On the contrary, FLUO-CLE gives good extracellular architecture and not clear information of nucleocytoplasmic abnormality. Samples on CVII for seven out of nine patients clearly showed cytoplasm of suspect cells and nuclei. In real time, fluorescence observed on bandwidth (673-800 nm) with HAL and FLUO was associated with the presence of cancer, with a sensibility and specificity of 80% and 100%, respectively. CONCLUSIONS: Real-time cytodetection was feasible using two fluorophores (FLUO and HAL) and the new system of CVII. This technology was useful to observe cytoplasm, nuclei, and nucleocytoplasmic abnormality, but an improved system is necessary (to overcome the overlapping of fluorescence) to increase the specificity.


Subject(s)
Microscopy, Confocal/methods , Urinary Bladder Neoplasms/diagnostic imaging , Administration, Intravesical , Aged , Aged, 80 and over , Aminolevulinic Acid/analogs & derivatives , Aminolevulinic Acid/chemistry , Cell Nucleus/metabolism , Cross-Sectional Studies , Cytoplasm/metabolism , Diagnosis, Computer-Assisted , Female , Fluorescein/chemistry , Fluorescence , Fluorescent Dyes , France , Humans , Lasers , Male , Middle Aged , Photochemotherapy/methods , Prospective Studies , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/surgery
9.
Cancer Prev Res (Phila) ; 10(3): 177-187, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28096238

ABSTRACT

Accruing evidence indicates that exposure to environmental compounds may adversely affect human health and promote carcinogenesis. Triclosan (TCS), an antimicrobial agent widely used as a preservative in personal care products, has been shown to act as an endocrine disruptor in hormone-dependent tissues. Here, we demonstrate a new molecular mechanism by which TCS stimulates the secretion by human prostate cancer stromal cells of vascular endothelial growth factor (VEGF), a factor known to promote tumor growth. This mechanism involves an increase in intracellular calcium levels due to the direct activation of a membrane ion channel. Using calcium imaging and electrophysiology techniques, we show for the first time that environmentally relevant concentrations of TCS activate a cation channel of the TRP family, TRPA1 (Transient Receptor Potential Ankirin 1), in primary cultured human prostate cancer stromal cells. The TCS-induced TRPA1 activation increased basal calcium in stromal cells and stimulated the secretion of VEGF and epithelial cells proliferation. Interestingly, immunofluorescence labeling performed on formalin-fixed paraffin-embedded prostate tissues showed an exclusive expression of the TRPA1 channel in prostate cancer stromal cells. Our data demonstrate an impact of the environmental factor TCS on the tumor microenvironment interactions, by activating a tumor stroma-specific TRPA1 ion channel. Cancer Prev Res; 10(3); 177-87. ©2017 AACR.


Subject(s)
Anti-Infective Agents, Local/toxicity , Calcium Channels/metabolism , Nerve Tissue Proteins/metabolism , Prostatic Neoplasms/metabolism , Stromal Cells/drug effects , Transient Receptor Potential Channels/metabolism , Triclosan/toxicity , Vascular Endothelial Growth Factor A/metabolism , Carcinogens, Environmental/toxicity , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Male , Stromal Cells/metabolism , TRPA1 Cation Channel , Tumor Microenvironment/drug effects
10.
Oncotarget ; 7(20): 29063-80, 2016 May 17.
Article in English | MEDLINE | ID: mdl-27074561

ABSTRACT

Since its cloning a decade ago, TRPM8 channel has emerged as a promising prognostic marker and a putative therapeutic target in prostate cancer (PCa). However, recent studies have brought to light the complexity of TRPM8 isoforms in PCa. Consequently, the respective role of each TRPM8 isoform needs to be deciphered prior to considering TRPM8 as an attractive therapeutic target. Full-length (6 transmembrane (TM)-domain) TRPM8 channel is overexpressed in early PCa and repressed in advanced prostate tumors whereas the localization of the truncated, 4TM-TRPM8 channel (4 transmembrane (TM)-domain), in the membranes of endoplasmic reticulum (ER) is independent of the pathogenic status of epithelial cells. In the same line, expression of non-channel cytoplasmic small TRPM8 isoforms (namely sM8) is conserved in cancer cells. In this study, we identify sM8s as putative regulator of PCa cell death. Indeed, suppression of sM8 isoforms was found to induce concomitantly ER stress, oxidative stress, p21 expression and apoptosis in human epithelial prostate cancer cells. We furthermore demonstrate that induction of such mechanisms required the activity of 4TM-TRPM8 channels at the ER-mitochondria junction. Our study thus suggests that targeting sM8 could be an appropriate strategy to fight prostate cancer.


Subject(s)
Prostatic Neoplasms/pathology , TRPM Cation Channels/metabolism , Animals , Apoptosis/physiology , Cell Line, Tumor , Female , Heterografts , Humans , Male , Mice , Mice, Nude , Prostatic Neoplasms/metabolism , Protein Isoforms/metabolism
11.
Springerplus ; 2(1): 54, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23450760

ABSTRACT

Bisphenol A (BPA), the principal constituent of reusable water bottles, metal cans, and plastic food containers, has been shown to be involved in human prostate cancer (PCa) cell proliferation. The aim of the present study was to explore the effect of BPA on PCa cell migration and the pathways involved in these processes. Using the transwell technique, we clearly show for the first time that the pre-treatment of the cells with BPA (1-10 nM) induces human PCa cell migration. Using a calcium imaging technique, we show that BPA pre-treatment induces an amplification of Store-Operated Calcium Entry (SOCE) in LNCaP cells. RT-PCR and Western blot experiments allowed the identification of the ion channel proteins which are up-regulated by BPA pre-treatments. These include the Orai1 protein, which is known as an important SOCE actor in various cell systems, including human PCa cells. Using a siRNA strategy, we observed that BPA-induced amplification of SOCE was Orai1-dependent. Interestingly, the BPA-induced PCa cell migration was suppressed when the calcium entry was impaired by the use of SOCE inhibitors (SKF96365, BTP2), or when the extracellular calcium was chelated. Taken together, the results presented here show that BPA induces PCa cells migration via a modulation of the ion channel protein expression involved in calcium entry and in cancer cell migration. The present data provide novel insights into the molecular mechanisms involved in the effects of an environmental factor on cancer cells and suggest both the necessity of preventive measures and the possibility of targeting ion channels in the treatment of PCa cell metastasis.

12.
Urology ; 80(5): 1162.e1-5, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22950991

ABSTRACT

OBJECTIVE: To improve the sensitivity of white light cystoscopy, photodynamic diagnosis (PDD) is useful but has low specificity. Recently, confocal laser endomicroscopy (CLE) has been used for the diagnosis of urothelial cell carcinoma. The main objective was to examine the feasibility of simultaneous PDD and CLE. A secondary objective was to determine whether hexyl aminolevulinic acid (HAL) can be used just as fluorescein for CLE. METHODS: In the present prospective single-center study with a same-patient comparison, patients with suspected urothelial cell carcinoma underwent surgical exploration after receiving a bladder instillation of HAL. After resection of suspected lesions under blue light, the samples were inspected ex vivo using CLE with and without fluorescein. Simultaneous blue light CLE inspection was performed. All samples were then transferred to the pathology laboratory for the classic analysis. RESULTS: Of the 12 patients studied, blue light cystoscopy revealed suspect lesions in 11; 10 had pathology proven urothelial cell carcinoma. CLE analysis was not modified by sample exposure to blue light, which facilitated orientation of the fiber toward the suspect red fluorescence areas. The fluorescence obtained with HAL-CLE was insufficient for microscopic histologic analysis, unlike the resolution obtained with fluorescein. Comparing CLE and the pathologic findings was possible and conclusive for 4 of 12 samples. CONCLUSION: Combining PDD and CLE ex vivo demonstrated the usefulness of HAL for guiding blue light CLE. HAL was insufficient to allow histologic CLE, which required the use of fluorescein. The results of this pilot study have indicated the feasibility of CLE. However, an in vivo method incorporating fluorescein and PDD will be required to improve the diagnostic specificity of PDD alone.


Subject(s)
Carcinoma, Transitional Cell/diagnosis , Cystoscopy , Fluorescein , Microscopy, Confocal/methods , Photosensitizing Agents , Urinary Bladder Neoplasms/diagnosis , Urothelium/pathology , Administration, Intravesical , Diagnosis, Differential , Feasibility Studies , Fluorescein/administration & dosage , Fluorescent Dyes/administration & dosage , Humans , Photosensitizing Agents/administration & dosage , Pilot Projects , Prospective Studies , Reproducibility of Results
14.
J Clin Invest ; 117(6): 1647-57, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17510704

ABSTRACT

In recent years, the transient receptor potential melastatin member 8 (TRPM8) channel has emerged as a promising prognostic marker and putative therapeutic target in prostate cancer (PCa). However, the mechanisms of prostate-specific regulation and functional evolution of TRPM8 during PCa progression remain unclear. Here we show, for the first time to our knowledge, that only secretory mature differentiated human prostate primary epithelial (PrPE) luminal cells expressed functional plasma membrane TRPM8 ((PM)TRPM8) channels. Moreover, PCa epithelial cells obtained from in situ PCa were characterized by a significantly stronger (PM)TRPM8-mediated current than that in normal cells. This (PM)TRPM8 activity was abolished in dedifferentiated PrPE cells that had lost their luminal secretory phenotype. However, we found that in contrast to (PM)TRPM8, endoplasmic reticulum TRPM8 ((ER)TRPM8) retained its function as an ER Ca(2+) release channel, independent of cell differentiation. We hypothesize that the constitutive activity of (ER)TRPM8 may result from the expression of a truncated TRPM8 splice variant. Our study provides insight into the role of TRPM8 in PCa progression and suggests that TRPM8 is a potentially attractive target for therapeutic intervention: specific inhibition of either (ER)TRPM8 or (PM)TRPM8 may be useful, depending on the stage and androgen sensitivity of the targeted PCa.


Subject(s)
Prostate/cytology , Prostate/metabolism , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , TRPM Cation Channels/metabolism , Alternative Splicing , Base Sequence , Biomarkers, Tumor/metabolism , Cell Differentiation , Cell Line, Tumor , Cell Membrane/metabolism , Endoplasmic Reticulum/metabolism , Epithelial Cells/cytology , Epithelial Cells/metabolism , Humans , Male , Prostatic Neoplasms/genetics , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , RNA, Small Interfering/genetics , Subcellular Fractions/metabolism , TRPM Cation Channels/genetics
16.
Cancer Res ; 66(4): 2038-47, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16489003

ABSTRACT

One major clinical problem with prostate cancer is the cells' ability to survive and proliferate upon androgen withdrawal. Because Ca2+ is central to growth control, understanding the mechanisms of Ca2+ homeostasis involved in prostate cancer cell proliferation is imperative for new therapeutic strategies. Here, we show that agonist-mediated stimulation of alpha1-adrenergic receptors (alpha1-AR) promotes proliferation of the primary human prostate cancer epithelial (hPCE) cells by inducing store-independent Ca2+ entry and subsequent activation of nuclear factor of activated T cells (NFAT) transcription factor. Such an agonist-induced Ca2+ entry (ACE) relied mostly on transient receptor potential canonical 6 (TRPC6) channels, whose silencing by antisense hybrid depletion decreased both hPCE cell proliferation and ACE. In contrast, ACE and related growth arrest associated with purinergic receptors (P2Y-R) stimulation involved neither TRPC6 nor NFAT. Our findings show that alpha1-AR signaling requires the coupled activation of TRPC6 channels and NFAT to promote proliferation of hPCE cells and thereby suggest TRPC6 as a novel potential therapeutic target.


Subject(s)
Calcium/metabolism , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Transient Receptor Potential Channels/metabolism , Adenosine Triphosphate/pharmacology , Adrenergic alpha-1 Receptor Agonists , Adrenergic alpha-Agonists/pharmacology , Calcium Signaling/physiology , Cell Growth Processes/physiology , Epithelial Cells/metabolism , Epithelial Cells/pathology , Humans , Male , NF-kappa B/metabolism , NFATC Transcription Factors/metabolism , Phenylephrine/pharmacology , Receptors, Purinergic/metabolism , TRPC Cation Channels/metabolism , TRPC6 Cation Channel , Up-Regulation
18.
Biochem J ; 377(Pt 3): 569-78, 2004 Feb 01.
Article in English | MEDLINE | ID: mdl-14565846

ABSTRACT

PRL (prolactin) has been implicated in the proliferation and differentiation of numerous tissues, including the prostate gland. However, the PRL-R (PRL receptor) signal transduction pathway, leading to the stimulation of cell proliferation, remains unclear and has yet to be mapped. The present study was undertaken to develop a clear understanding of the mechanisms involved in this pathway and, in particular, to determine the role of K(+) channels. We used androgen-sensitive prostate cancer (LNCaP) cells whose proliferation is known to be stimulated by PRL. Reverse transcriptase PCR analysis showed that LNCaP cells express a long form of PRL-R, but do not produce its intermediate isoform. Patch-clamp techniques showed that the application of 5 nM PRL increased both the macroscopic K(+) current amplitude and the single K(+)-channel open probability. This single-channel activity increase was reduced by the tyrosine kinase inhibitors genistein, herbimycin A and lavandustine A, thereby indicating that tyrosine kinase phosphorylation is required in PRL-induced K(+) channel stimulation. PRL enhances p59( fyn ) phosphorylation by a factor of 2 after a 10 min application in culture. In addition, where an antip59( fyn ) antibody is present in the patch pipette, PRL no longer increases K(+) current amplitude. Furthermore, the PRL-stimulated proliferation is inhibited by the K(+) channel inhibitors alpha-dendrotoxin and tetraethylammonium. Thus, as K(+) channels are known to be involved in LNCaP cell proliferation, we suggest that K(+) channel modulation by PRL, via p59( fyn ) pathway, is the primary ionic event in PRL signal transduction, triggering cell proliferation.


Subject(s)
Potassium Channels/physiology , Prolactin/physiology , Receptors, Prolactin/physiology , Calcium/metabolism , Cell Division/drug effects , Cell Division/physiology , Cell Line, Tumor , Cytosol/chemistry , Cytosol/drug effects , Humans , Ion Channel Gating/drug effects , Ion Channel Gating/physiology , Male , Membrane Potentials/drug effects , Membrane Potentials/physiology , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/metabolism , Neoplasm Proteins/physiology , Patch-Clamp Techniques , Phosphorylation/drug effects , Potassium Channels/metabolism , Prolactin/pharmacology , Protein Isoforms/biosynthesis , Protein Isoforms/metabolism , Protein Isoforms/physiology , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/physiology , Proto-Oncogene Proteins c-fyn , Receptors, Prolactin/biosynthesis , Receptors, Prolactin/metabolism , Signal Transduction/drug effects , Signal Transduction/physiology
20.
J Clin Invest ; 111(11): 1691-701, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12782672

ABSTRACT

The prostate gland is a rich source of alpha1-adrenergic receptors (alpha1-ARs). alpha1-AR antagonists are commonly used in the treatment of benign prostatic hyperplasia symptoms, due to their action on smooth muscle cells. However, virtually nothing is known about the role of alpha1-ARs in epithelial cells. Here, by using two human prostate cancer epithelial (hPCE) cell models - primary cells from resection specimens (primary hPCE cells) and an LNCaP (lymph node carcinoma of the prostate) cell line - we identify an alpha1A subtype of adrenergic receptor (alpha1A-AR) and show its functional coupling to plasmalemmal cationic channels via direct diacylglycerol (DAG) gating. In both cell types, agonist-mediated stimulation of alpha1A-ARs and DAG analogues activated similar cationic membrane currents and Ca(2+) influx. These currents were sensitive to the alpha1A-AR antagonists, prazosin and WB4101, and to transient receptor potential (TRP) channel blockers, 2-aminophenyl borate and SK&F 96365. Chronic activation of alpha1A-ARs enhanced LNCaP cell proliferation, which could be antagonized by alpha1A-AR and TRP inhibitors. Collectively, our results suggest that alpha1-ARs play a role in promoting hPCE cell proliferation via TRP channels.


Subject(s)
Calcium/metabolism , Epithelial Cells/metabolism , Prostatic Neoplasms/metabolism , Receptors, Adrenergic, alpha-1/physiology , Adrenergic alpha-1 Receptor Antagonists , Adrenergic alpha-Antagonists/pharmacology , Blotting, Western , Boron Compounds/pharmacology , Calcium Channel Blockers/pharmacology , Cations , Cell Division , Diglycerides/metabolism , Dioxanes/pharmacology , Electrophysiology , Humans , Imidazoles/pharmacology , Male , Microscopy, Fluorescence , Prazosin/pharmacology , Receptors, Adrenergic, alpha-1/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time Factors , Tumor Cells, Cultured
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