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OBJECTIVE: We evaluated the influence of the renin-angiotensin system (RAS) on intestinal inflammation and fibrosis. DESIGN: Cultured human colonic myofibroblast proliferation and collagen secretion were assessed following treatment with angiotensin (Ang) II and Ang (1-7), their receptor antagonists candesartan and A779, and the ACE inhibitor captopril. Circulating and intestinal RAS components were evaluated in patients with and without IBD. Disease outcomes in patients with IBD treated with ACE inhibitors and angiotensin receptor blockers (ARBs) were assessed in retrospective studies. RESULTS: Human colonic myofibroblast proliferation was reduced by Ang (1-7) in a dose-dependent manner (p<0.05). Ang II marginally but not significantly increased proliferation, an effect reversed by candesartan (p<0.001). Colonic myofibroblast collagen secretion was reduced by Ang (1-7) (p<0.05) and captopril (p<0.001), and was increased by Ang II (p<0.001). Patients with IBD had higher circulating renin (mean 25.4 vs 18.6 mIU/L, p=0.026) and ACE2:ACE ratio (mean 0.92 vs 0.69, p=0.015) than controls without IBD. RAS gene transcripts and peptides were identified in healthy and diseased bowels. Colonic mucosal Masson's trichrome staining correlated with Ang II (r=0.346, p=0.010) and inversely with ACE2 activity (r=-0.373, p=0.006). Patients with IBD who required surgery (1/37 vs 12/75, p=0.034) and hospitalisation (0/34 vs 8/68, p=0.049) over 2 years were less often treated with ACE inhibitors and ARBs than patients not requiring surgery or hospitalisation. CONCLUSIONS: The RAS mediates fibrosis in human cell cultures, is expressed in the intestine and perturbed in intestinal inflammation, and agents targeting this system are associated with improved disease outcomes.
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Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Bencimidazoles/farmacología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Miofibroblastos/efectos de los fármacos , Sistema Renina-Angiotensina/efectos de los fármacos , Tetrazoles/farmacología , Adulto , Compuestos de Bifenilo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Estudios de Cohortes , Colon/citología , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos , Femenino , Fibrosis/tratamiento farmacológico , Fibrosis/patología , Humanos , Enfermedades Inflamatorias del Intestino/patología , Masculino , Miofibroblastos/citología , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To interrogate enriched prostate cancer cells and autologous non-malignant prostate epithelial cells from men with localized prostate cancer, in order to identify early oncogenic pathways. PATIENTS AND METHODS: We collected malignant and matched non-malignant prostatectomy samples from men with adenocarcinoma involving two or more contiguous areas in only one lobe of the prostate. Tissue samples from both lobes were subjected to digestion and single-cell suspensions were prepared. Epithelial cell adhesion molecule-positive cells from cancerous and contralateral non-malignant (control) samples were isolated using magnetic beads, ensuring uniform populations were obtained for each donor. Unbiased RNA sequencing analysis was used to measure gene expression and for detection of transcribed mutations or splice variants that were over- or under-represented in malignant prostate epithelial cells relative to autologous control prostate epithelial cells. RESULTS: From five patient samples we identified 17 genes that were altered in prostate cancer epithelial cells, with 82% of genes being downregulated. Three genes, TDRD1, ANGTL4, and CLDN3, were consistently upregulated in malignant tissue. Malignant cells from three of the five patients showed evidence of upregulated ERG signalling, however, only one of these contained a TMPRSS2-ERG rearrangement. We did not identify mutations, gene rearrangements, or splice variants that were consistent amongst the patients. CONCLUSIONS: Events occurring early in prostate cancer oncogenesis in these samples were characterized by a predominant downregulation of gene expression along with upregulation of TDRD1, ANGTL4 and CLDN3. No consistent mutations or splice variants were observed, but upregulation of ERG signalling was seen both in the presence and absence of the classic TMPRSS2-ERG rearrangement.
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Adenocarcinoma/genética , Adenocarcinoma/patología , Carcinogénesis/genética , Células Epiteliales/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Adenocarcinoma/cirugía , Anciano , Proteína 4 Similar a la Angiopoyetina/genética , Proteínas de Ciclo Celular/genética , Claudina-3/genética , Regulación hacia Abajo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Reordenamiento Génico , Humanos , Masculino , Persona de Mediana Edad , Prostatectomía , Neoplasias de la Próstata/cirugía , ARN Lider Empalmado/fisiología , Serina Endopeptidasas/genética , Transducción de Señal , Regulador Transcripcional ERG/genética , Regulación hacia ArribaRESUMEN
OBJECTIVE: To characterize circulating oestrogen receptor ( ER) mutants and splice variants in men with advanced prostate cancer. MATERIALS AND METHODS: Sequential blood samples were obtained from men with advanced prostate cancer, and from healthy controls. Blood-derived RNA samples were analysed using droplet digital PCR for the presence of six ERα mutations (E380Q, L536Q, Y537C, Y537S, Y537N and D538G), and six ERα and ERß splice variants (ERα-66, ERα-36, ERß1, ERß2, ERß4 & ERß5). RESULTS: A total of 94 samples were collected from 42 men with advanced prostate cancer. Four mutations (E380Q, L536Q, Y537S and D538G) and all six splice variants were detected in patient samples. Splice variants were detectable in non-cancer control samples. The presence of ER mutations was associated with bone metastases and castration resistance. ERß splice variant concentrations decreased after successive lines of treatment. CONCLUSIONS: The ER mutations were detectable in plasma from patients with advanced prostate cancer. ER splice variants were frequently detected in both men with and without prostate cancer.
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Empalme Alternativo/fisiología , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/genética , Mutación , Neoplasias de la Próstata/genética , Anciano , Anciano de 80 o más Años , Empalme Alternativo/genética , Australia , Receptor alfa de Estrógeno/sangre , Receptor beta de Estrógeno/sangre , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , ARN Mensajero/genéticaRESUMEN
BACKGROUND: Serum free thiols (SFTs) reflecting oxidative stress appear to correlate with inflammatory bowel disease (IBD) activity. We aimed to evaluate the performance of SFTs concentrations vs endoscopic and histological activity, compare SFTs with established biomarkers, and identify clinical and laboratory parameters independently associated with SFT levels in IBD patients. METHODS: Patients with confirmed IBD undergoing routine ileocolonoscopy for activity assessment were prospectively recruited, with serum samples obtained concurrently for SFTs and routine bloods, plus fecal calprotectin and immunochemical tests were collectedâ ±30 days from ileocolonoscopy. Endoscopic activity was assessed via established indices and histological activity graded as inactive/mild/moderate. Receiver-operating characteristic curve analyses were utilized to assess performance of SFTs vs endoscopic activity, and multiple regression analysis was used to identify factors associated with SFT levels. RESULTS: A total of 141 (80 Crohn's disease, 61 ulcerative colitis) patients were recruited. Median SFTs were significantly lower in moderate vs inactive/mild endoscopic activity (309 µM vs 433/471 µM, respectively; Pâ <â .01). There was no significant difference in median SFTs across inactive/mild/moderate histological activity. SFTs achieved higher sensitivity than C-reactive protein in predicting moderate, endoscopically active disease (89% vs 78%; area under the curve, 0.80 each) yet was outperformed by fecal calprotectin (100%; area under the curve, 0.93). Advancing age and increasing albumin levels were independently associated with SFT levels, and thus are possible confounders. CONCLUSIONS: This prospective study has demonstrated the potential of SFTs as a serum biomarker in IBD. It was more sensitive than C-reactive protein, yet less sensitive than fecal biomarkers for prediction of endoscopically active IBD.
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PURPOSE: The Lumi-Solve photo-angioplasty drug eluting balloon catheter (DEBc) may afford safety advantages over current DEBc. Lumi-Solve utilises the guidewire (GW) port and lumen to deliver fibre-optic UV365nm light to the angioplasty balloon which may be problematic. We explore and evaluate alternative Lumi-Solve design options to circumvent fibre-optic use of the GW port and lumen which may enhance efficacy and clinical utility. METHODS: Effects of guidewire shadowing (GWS) on visible and UV365nm light transmission were evaluated and modelled in-silico. To evaluate the effect of a dedicated intra-balloon fibre-optic port, modified angioplasty balloons and sections of translucent polyethylene terephthalate (PET) GW port tubing were utilised. Investigation of the effect of GWS on chemical and biological photo-activation of balloon surface drug was performed utilising LCMS analysis and inhibition of histone deacetylase activity (HDACi) was measured in human umbilical vein endothelial cells (HUVEC). RESULTS: Parallel fibre-optic and GW port configurations generated a GWS of approximately 18.0% of the evaluable balloon surface area and attenuated both visible and UV light intensity by 20.0-25.0% and reduced chemical photo-activation of balloon surface drug and HDACi by at least 40-45%. Alternative fibre-optic port configurations including a spiral design significantly mitigated GWS effects on UV light transmission. CONCLUSIONS: To avoid use of the GW port and its associated complications a dedicated third port and lumen for the Lumi-Solve fibre-optic may be required. To maximize balloon surface chemical and biological photo-activation, non-parallel, intra-balloon, fibre-optic lumen trajectories, including a spiral design may be useful.
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Angioplastia de Balón , Dispositivos de Acceso Vascular , Humanos , Angioplastia de Balón/efectos adversos , Células Endoteliales de la Vena Umbilical HumanaRESUMEN
BACKGROUND: Intraoperative tumour spillage can be concerning during cancer excisions, given it can lead to tumour-cell re-implantation and local recurrence. Examples include bladder tumour recurrences post-transurethral resection, or peritoneal spillage during laparotomy/laparoscopy for bowel and ovarian cancers. One approach to reducing implantation is mechanical wash out of free-floating tumour cells. Irrigation with water may have additional effectiveness compared to iso-osmotic irrigants (e.g. saline) by causing osmotic cytolysis, but this is not well-characterised. This in vitro study aimed to ascertain the time-course of osmotic effects of water on various cancer cell lines to provide guidance for clinical usage. METHODS: Assays were conducted on six cancer cell lines (bladder [HT1197, HT1376], colon [KM12, LIM2405], kidney [SKRC52], and ovarian [COV434]). Cells were exposed to water or 0.9% saline and cell counts were performed using a haemocytometer at 10, 20, 40, 60, 120 and 180 min. Cell viability was determined using Trypan Blue exclusion. RESULTS: In all cell lines, exposure to water led to 100% cell lysis within a median time of 40 min (range 10-180 min), while exposure to saline led to a gradual decline in cell viability (median 50.2%, range 6.7%-100.0%) over 3 h, and did not result in complete cell lysis. An increase in osmotic gradient equivalent to a concentration of 5% NaCl was sufficient to impede the effects of water-mediated cell lysis. CONCLUSION: Our studies suggest that water has a rapid osmolytic effect on cancer cells. The required exposure time to reach 0% cell viability varied between individual cell lines.
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Neoplasias Ováricas , Agua , Cistectomía , Humanos , Recurrencia Local de Neoplasia , Solución Salina , Irrigación TerapéuticaRESUMEN
Management of advanced prostate cancer remains complex, with substantial changes in treatment options emerging in recent years having implications for treatment selection and sequencing. Recognition of the importance of androgen signaling has led to life-prolonging treatments, as well as "liquid biopsy" techniques to guide these treatments in some settings. Therapies that target estrogen receptor signaling are efficacious but infrequently used options for treatment of castration-resistant prostate cancer. It is possible that nuances of estrogen receptor (ER) signaling, or selective modulation of ER signaling, might favorably influence outcomes in castration-resistant prostate cancer. Expression of ERs and their variants has been investigated in other cancers such as breast. Constitutively activating gene alterations can potentially lead to ER activation and subsequently promote cancer progression. The identification of these aberrations may help identify cancer phenotypes that are susceptible or resistant to therapies involved in ER signaling. This review outlines the current literature regarding ER signaling in prostate cancer, and provides background for exploration of potentially useful ER signaling biomarkers in advanced prostate cancer.
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Carcinogénesis/metabolismo , Neoplasias de la Próstata/metabolismo , Receptores de Estrógenos/metabolismo , Transducción de Señal , Humanos , Biopsia Líquida , Masculino , Empalme del ARN/genética , Receptores de Estrógenos/genéticaRESUMEN
"Cancer stem cells" that resist conventional treatments may be a cause of therapeutic failure in melanoma. We report a subpopulation of clonogenic melanoma cells that are characterized by high prominin-1/CD133 expression in melanoma and melanoma cell lines. These cells have enhanced clonogenicity and self-renewal in vitro, and serve as a limited in vitro model for melanoma stem cells. In some cases clonogenic CD133(+) melanoma cells show increased expression of some cancer/testis (CT) antigens. The expression of NY-ESO-1 in an HLA-A2 expressing cell line allowed CD133(+) clonogenic melanoma cells to be targeted for killing in vitro by NY-ESO-1-specific CD8(+) T-lymphocytes. Our in vitro findings raise the hypothesis that if melanoma stem cells express CT antigens in vivo that immune targeting of these antigens may be a viable clinical strategy for the adjuvant treatment of melanoma.
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Antígenos CD/metabolismo , Antígenos de Neoplasias/inmunología , Vacunas contra el Cáncer/uso terapéutico , Glicoproteínas/metabolismo , Melanoma/inmunología , Proteínas de la Membrana/inmunología , Péptidos/metabolismo , Neoplasias Cutáneas/inmunología , Antígeno AC133 , Linfocitos T CD8-positivos/inmunología , Ensayo de Unidades Formadoras de Colonias , Citotoxicidad Inmunológica , Técnica del Anticuerpo Fluorescente , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , Melanoma/secundario , Melanoma/terapia , Fragmentos de Péptidos/inmunología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/terapia , Linfocitos T Citotóxicos/inmunologíaRESUMEN
BACKGROUND: The intestinal vitamin D receptor (VDR) remains poorly characterized in patients with inflammatory bowel disease (IBD). METHODS: Colonoscopic biopsies and intestinal resection specimens from the terminal ileum, ascending and sigmoid colon, from patients with and without IBD, were analyzed for VDR mRNA quantification by polymerase chain reaction, and protein localization and semi-quantification by immunohistochemistry. The relationship between VDR and intestinal inflammation, serum 25(OH)D and oral vitamin D intake was elicited. RESULTS: A total of 725 biopsies from 20 patients with Crohn's disease (CD), 15 with ulcerative colitis (UC) and 14 non-IBD controls who underwent colonoscopy were studied. VDR gene expression and protein staining intensity was similar across all three groups, and across the intestinal segments. Sigmoid colon VDR mRNA expression inversely correlated with faecal calprotectin (r = -0.64, p = 0.026) and histological score (r = -0.67, p = 0.006) in UC, and histological score (r = -0.58, p = 0.019) in patients with CD. VDR staining intensity was higher in quiescent than diseased segments. No relationship with serum 25(OH)D or oral vitamin D intake was noted. Immunohistochemical staining of 28 intestinal resection specimens from 15 patients (5 each with CD, UC and non-IBD controls) showed diffuse VDR staining in the mucosa, submucosa and circular muscle. CONCLUSIONS: VDR transcript expression and protein staining intensity are inversely related to inflammation in IBD, but unrelated to serum 25(OH)D, and similar to non-IBD controls. Strategies to upregulate intestinal VDR, potentially translating to modulation of disease activity, require investigation.
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The isolation and molecular analysis of highly purified cell populations from complex, heterogeneous tissues has been a challenge for many years. Spermatogenesis in the testis is a particularly difficult process to study given the unique multiple cellular associations within the seminiferous epithelium, making the isolation of specific cell types difficult. Laser-capture microdissection (LCM) is a recently developed technique that enables the isolation of individual cell populations from complex tissues. This technology has enhanced our ability to directly examine gene expression in enriched testicular cell populations by routine methods of gene expression analysis, such as real-time RT-PCR, differential display, and gene microarrays. The application of LCM has however introduced methodological hurdles that have not been encountered with more conventional molecular analyses of whole tissue. In particular, tissue handling (i.e. fixation, storage, and staining), consumables (e.g. slide choice), staining reagents (conventional H&E vs. fluorescence), extraction methods, and downstream applications have all required re-optimisation to facilitate differential gene expression analysis using the small amounts of material obtained using LCM. This review will discuss three critical issues that are essential for successful procurement of cells from testicular tissue sections; tissue morphology, capture success, and maintenance of molecular integrity. The importance of these issues will be discussed with specific reference to the two most commonly used LCM systems; the Arcturus PixCell IIe and PALM systems. The rat testis will be used as a model, and emphasis will be placed on issues of tissue handling, processing, and staining methods, including the application of fluorescence techniques to assist in the identification of cells of interest for the purposes of mRNA expression analysis.
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Expresión Génica , Rayos Láser , Microdisección/instrumentación , Microdisección/métodos , Testículo/citología , Animales , Separación Celular , Masculino , ARN Mensajero/biosíntesis , Ratas , Testículo/metabolismoRESUMEN
Ectopic pregnancies complicate 1-2 pregnancies and are a leading cause of maternal death. An effective oral drug therapy that replaces surgery might make its treatment safer, cheaper, simpler and therefore more widely accessible. The only current medical treatment offered to women is intramuscular methotrexate, but this only reliably resolves smaller ectopic pregnancies. As such, many ectopic pregnancies require surgical excision. We show that vinorelbine, an orally available chemotherapeutic agent, potently induced placental cell death but did not harm fertility in mice. Vinorelbine was 100-1000 times more potent than methotrexate in inducing placental cell death in vitro, and more potent than combination methotrexate and gefitinib (another proposed treatment for ectopic pregnancy being evaluated in phase III trials). Mechanistically, it caused microtubule condensation, blocked mitosis and activated the apoptosis cascade in placental cells. Vinorelbine was more efficacious than methotrexate±gefitinib in reducing the volume of placental cell tumors xenografted subcutaneously in SCID mice. Mice exposed to vinorelbine and allowed to breed, following a four week washout period, displayed normal fertility, however long-term fertility was not assessed. Human Fallopian tubes treated with vinorelbine did not exhibit up-regulation of apoptosis molecules. Our findings show that placental cells appear sensitive to vinorelbine and it has potential as a tablet-only approach to treat ectopic pregnancy.
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Muerte Celular/efectos de los fármacos , Fertilidad/efectos de los fármacos , Placenta/citología , Placenta/efectos de los fármacos , Vinblastina/análogos & derivados , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Gefitinib , Xenoinjertos , Humanos , Metotrexato/farmacología , Ratones , Microtúbulos/metabolismo , Miosis/tratamiento farmacológico , Embarazo , Embarazo Ectópico/tratamiento farmacológico , Embarazo Ectópico/patología , Quinazolinas/farmacología , Trofoblastos/efectos de los fármacos , Trofoblastos/metabolismo , Vinblastina/farmacología , Vinblastina/uso terapéutico , VinorelbinaRESUMEN
After many years of limited treatment options for patients with metastatic castration-resistant prostate cancer (mCRPC), multiple systemic therapies are now available, providing patients with significant improvements in survival, symptom control and bone health. Most of the recent advances in this area have been based on better understanding of mCRPC biology, particularly with respect to the key role of androgen receptor signalling. However, most therapies are targeted towards the malignant epithelial cell component of the cancer and it should not be forgotten that cancer cells exist in close and symbiotic relationships with other components of the tumour. Paracrine and stromal signals are often critical to the growth of the cancer and represent new potential therapeutic targets that are separate from the malignant epithelial cells. The stroma produces numerous growth factors, including vascular endothelial growth factor family members, platelet-derived growth factors and fibroblast growth factors, which are all critical for tumour growth. Targeting prostate-cancer-associated fibroblasts in order to destroy the physical and functional scaffold of a cancer is also a logical approach. The interaction between prostate cancer and the immune system remains an active topic of basic and clinical research, with cytokines, chemokines and growth factors being potential targets for therapy. The biology of epithelial-mesenchymal transition and of circulating tumour cells might also provide insight into new therapeutic targets.
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Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Comunicación Paracrina , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Células del Estroma/patología , Animales , Humanos , Masculino , Comunicación Paracrina/efectos de los fármacos , Comunicación Paracrina/fisiología , Células del Estroma/efectos de los fármacos , Células del Estroma/fisiologíaRESUMEN
Abnormal trophoblast growth can cause life-threatening disorders such as ectopic pregnancy, choriocarcinoma, and placenta accreta. EnGeneIC Delivery Vehicles (EDVs) are nanocells that can promote tissue-specific delivery of drugs and may be useful to medically treat such disorders. The objective of this study was to determine whether EDVs loaded with the chemotherapeutic doxorubicin and targeting the epidermal growth factor receptor (EGFR, very highly expressed on the placental surface) can regress placental cells in vitro, ex vivo, and in vivo. In female SCID mice, EGFR-targeted EDVs induced greater inhibition of JEG-3 (choriocarcinoma cells) tumor xenografts, compared with EDVs targeting an irrelevant antigen (nontargeted EDVs) or naked doxorubicin. EGFR-targeted EDVs were more readily taken up by human placental explants ex vivo and induced increased apoptosis (M30 antibody) compared with nontargeted EDVs. In vitro, EGFR-targeted EDVs administered to JEG-3 cells resulted in a dose-dependent inhibition of cell viability, proliferation, and increased apoptosis, a finding confirmed by continuous monitoring by xCELLigence. In conclusion, EGFR-targeted EDVs loaded with doxorubicin significantly inhibited trophoblastic tumor cell growth in vivo and in vitro and induced significant cell death ex vivo, potentially mediated by increasing apoptosis and decreasing proliferation. EDVs may be a novel nanoparticle treatment for ectopic pregnancy and other disorders of trophoblast growth.
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Doxorrubicina/administración & dosificación , Receptores ErbB/metabolismo , Nanopartículas/administración & dosificación , Embarazo Ectópico/tratamiento farmacológico , Neoplasias Trofoblásticas/tratamiento farmacológico , Animales , Femenino , Ratones , Ratones SCID , Embarazo , Células Tumorales Cultivadas , Neoplasias Uterinas/tratamiento farmacológicoRESUMEN
The production of mature sperm is reliant on androgen action within the testis, and it is well established that androgens act on receptors within the somatic Sertoli cells to stimulate male germ cell development. Mice lacking Sertoli cell androgen receptors (AR) show late meiotic germ cell arrest, suggesting Sertoli cells transduce the androgenic stimulus co-ordinating this essential step in spermatogenesis. This study aimed to identify germ cell proteins responsive to changes in testicular androgen levels and thereby elucidate mechanisms by which androgens regulate meiosis. Testicular androgen levels were suppressed for 9 weeks using testosterone and estradiol-filled silastic implants, followed by a short period of either further androgen suppression (via an AR antagonist) or the restoration of intratesticular testosterone levels. Comparative proteomics were performed on protein extracts from enriched meiotic cell preparations from adult rats undergoing androgen deprivation and replacement in vivo. Loss of androgenic stimulus caused changes in proteins with known roles in meiosis (including Nasp and Hsp70-2), apoptosis (including Diablo), cell signalling (including 14-3-3 isoforms), oxidative stress, DNA repair, and RNA processing. Immunostaining for oxidised DNA adducts confirmed spermatocytes undergo oxidative stress-induced DNA damage during androgen suppression. An increase in PCNA and an associated ubiquitin-conjugating enzyme (Ubc13) suggested a role for PCNA-mediated regulation of DNA repair pathways in spermatocytes. Changes in cytoplasmic SUMO1 localisation in spermatocytes were paralleled by changes in the levels of free SUMO1 and of a subunit of its activating complex, suggesting sumoylation in spermatocytes is modified by androgen action on Sertoli cells. We conclude that Sertoli cells, in response to androgens, modulate protein translation and post-translational events in spermatocytes that impact on their metabolism, survival, and completion of meiosis.
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Andrógenos/fisiología , Estradiol/fisiología , Meiosis , Proteoma/metabolismo , Espermatogénesis , Testosterona/fisiología , Animales , Apoptosis , Células Cultivadas , ARN Helicasas DEAD-box/metabolismo , Aductos de ADN/metabolismo , Reparación del ADN , Masculino , Estrés Oxidativo , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Procesamiento Proteico-Postraduccional , Proteómica , Empalme del ARN , Ratas , Ratas Sprague-Dawley , Proteína SUMO-1/metabolismo , Espermatocitos/metabolismo , Espermatocitos/fisiologíaRESUMEN
Claudin-11 and occludin are protein components in tight junctions (TJs) between Sertoli cells which are important for the maintenance of the blood-testis barrier. Barrier formation occurs during puberty, with evidence suggesting hormonal regulation of both claudin-11 and occludin. This study aimed to investigate the regulation of claudin-11 and occludin mRNA expression by testosterone (T) and FSH and their immunolocalisation at rat Sertoli cell TJs in vitro, and to correlate any steroid regulation with the functional capacity of TJs. Sertoli cells formed functional TJs within 3 days as assessed by transepithelial electrical resistance (TER). Both T and dihydrotestosterone significantly (P < 0.01) increased TER twofold and claudin-11 mRNA two- to threefold within 3 days. FSH partially stimulated TER and claudin-11 mRNA, but estradiol had no effect. T also promoted claudin-11 localisation into extensive intercellular contacts. In contrast to claudin-11, Tand FSH did not change occludin mRNA expression, however, T promoted localisation of occludin at cell contacts in a similar manner to claudin-11. Addition of flutamide to T-stimulated cells caused a twofold decrease in both TER and claudin-11 mRNA expression, and resulted in the loss of both proteins from cell contacts. This effect was reversible following flutamide removal. It is concluded that androgens i) co-regulate claudin-11 mRNA expression and TER, implicating claudin-11 in TJ formation and ii) promote the localisation of claudin-11 and occludin at Sertoli cell contacts. Hence, the ability of androgens to maintain spermatogenesis in vivo is partly via their effects on TJ proteins and regulation of the blood-testis barrier.
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Barrera Hematotesticular/efectos de los fármacos , Proteínas del Tejido Nervioso/análisis , Células de Sertoli/química , Testosterona/farmacología , Uniones Estrechas/química , Animales , Células Cultivadas , Claudinas , Hormona Folículo Estimulante/farmacología , Inmunohistoquímica , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Ocludina , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células de Sertoli/efectos de los fármacos , Células de Sertoli/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismoRESUMEN
Spermatogenesis in the rat consists of 14 unique morphologic cellular associations between Sertoli cells and developing germ cells within the seminiferous epithelium. The complexity of the cellular associations leads to difficulty in the isolation of individual cells at a defined stage of development for the study of their unique patterns of gene or protein expression. Thus, laser-capture microdissection is an ideal technique to permit such analysis. This study used laser-capture microdissection and real-time reverse transcription-polymerase chain reaction (RT-PCR) to quantitate the stage-specific expression of a series of genes of functional significance in hormonal regulation and cell-cell interactions in spermatogenesis, including cathepsin-L, CREM-tau, transition protein-1, androgen receptor, beta1-integrin, N-cadherin, and hypoxanthine phosphoribosyltransferase (HPRT). Frozen sections (10 micro m) were obtained from normal adult rat testes. Laser-capture microdissection (LCM) was used to capture all cells in cross-sections of seminiferous tubules that were grouped into stages I-V, VII-VIII, and IX-XIII. Transition protein-1 expression was lowest during stages I-V and increased 5.9-fold during stages VII-VIII and IX-XIII (P < 0.01). Cathepsin-L expression was highest during stages I-V and VII-VIII, falling 4.9-fold during stages IX-XIII (P < 0.05). Similarly, CREM-tau expression was highest during stages I-V and VII-VIII, falling 1.6-fold during stages IX-XIII (P < 0.05). A novel CREM-tau isoform lacking the phosphorylation domain was also characterized but was not stage-specific. beta1-Integrin, N-cadherin, and androgen receptor expression did not change between the spermatogenic stages examined. HPRT housekeeper expression was lowest during stages I-V but increased 1.5-fold during stages VII-VIII and IX-XIII (P < 0.05). This study is the first to apply LCM and real-time RT-PCR analysis to quantitate stage-specific changes in the expression of multiple genes in the seminiferous epithelium.