transforming-growth-factor-beta has been researched along with Prostatic-Neoplasms--Castration-Resistant* in 16 studies
1 review(s) available for transforming-growth-factor-beta and Prostatic-Neoplasms--Castration-Resistant
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Efficacy Against Human Prostate Cancer by Prostate-specific Membrane Antigen-specific, Transforming Growth Factor-β Insensitive Genetically Targeted CD8
Current immunotherapy has limited efficacy on metastatic castrate-resistant prostate cancer (mCRPC). We therefore sought to improve the antitumor ability of mCRPC patient-derived CD8. We investigated the role of a novel chimeric antigen receptor T-immunotherapy based on autologous metastatic castrate-resistant prostate cancer patient-derived prostate-specific membrane antigen (PSMA)-specific, transforming growth factor-ß insensitive CD8 Topics: Animals; Antigens, Surface; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Disease Models, Animal; Glutamate Carboxypeptidase II; Humans; Immunotherapy; Male; Mice; Mice, Nude; Molecular Targeted Therapy; Neoplasm Metastasis; Prostate-Specific Antigen; Prostatic Neoplasms, Castration-Resistant; Transforming Growth Factor beta; Treatment Outcome | 2018 |
2 trial(s) available for transforming-growth-factor-beta and Prostatic-Neoplasms--Castration-Resistant
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PSMA-targeting TGFβ-insensitive armored CAR T cells in metastatic castration-resistant prostate cancer: a phase 1 trial.
Chimeric antigen receptor (CAR) T cells have demonstrated promising efficacy, particularly in hematologic malignancies. One challenge regarding CAR T cells in solid tumors is the immunosuppressive tumor microenvironment (TME), characterized by high levels of multiple inhibitory factors, including transforming growth factor (TGF)-β. We report results from an in-human phase 1 trial of castration-resistant, prostate cancer-directed CAR T cells armored with a dominant-negative TGF-β receptor (NCT03089203). Primary endpoints were safety and feasibility, while secondary objectives included assessment of CAR T cell distribution, bioactivity and disease response. All prespecified endpoints were met. Eighteen patients enrolled, and 13 subjects received therapy across four dose levels. Five of the 13 patients developed grade ≥2 cytokine release syndrome (CRS), including one patient who experienced a marked clonal CAR T cell expansion, >98% reduction in prostate-specific antigen (PSA) and death following grade 4 CRS with concurrent sepsis. Acute increases in inflammatory cytokines correlated with manageable high-grade CRS events. Three additional patients achieved a PSA reduction of ≥30%, with CAR T cell failure accompanied by upregulation of multiple TME-localized inhibitory molecules following adoptive cell transfer. CAR T cell kinetics revealed expansion in blood and tumor trafficking. Thus, clinical application of TGF-β-resistant CAR T cells is feasible and generally safe. Future studies should use superior multipronged approaches against the TME to improve outcomes. Topics: Humans; Immunotherapy, Adoptive; Male; Prostate-Specific Antigen; Prostatic Neoplasms, Castration-Resistant; Receptors, Chimeric Antigen; T-Lymphocytes; Transforming Growth Factor beta; Tumor Microenvironment | 2022 |
Quick efficacy seeking trial (QuEST1): a novel combination immunotherapy study designed for rapid clinical signal assessment metastatic castration-resistant prostate cancer.
Advances in immunotherapy utilizing immune checkpoint inhibitors (ICIs) have transformed the treatment landscapes of several malignancies in recent years. Oncologists are now tasked with extending these benefits to a greater number of patients and tumor types. Metastatic castration-resistant prostate cancer (mCRPC) infrequently responds to ICIs, while the cellular vaccine approved for mCRPC, sipuleucel-T, provides a 4-month survival benefit but does not produce clinical responses as monotherapy. However, many novel and generally well-tolerated immune oncology agents with potential for immune synergy and/or additive effects are undergoing clinical development. This availability presents opportunities to develop adaptive-design combination clinical trials aimed to generate, expand, and facilitate antitumor immune responses. Here we describe a currently accruing phase I/II trial (NCT03493945) testing a brachyury-targeted antitumor vaccine, TGF-β TRAP/anti-PD-L1 antibody, an IL-15 agonist, and an IDO1 inhibitor in mCRPC.. This trial ( NCT03493945 ) was registered in National Clinical Trials on April 11th 2018. Topics: Antibodies, Bispecific; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; B7-H1 Antigen; Cancer Vaccines; Fetal Proteins; Humans; Immunotherapy; Indoleamine-Pyrrole 2,3,-Dioxygenase; Interleukin-15; Male; Oximes; Prostatic Neoplasms, Castration-Resistant; Proteins; Recombinant Fusion Proteins; Sulfonamides; T-Box Domain Proteins; Tissue Extracts; Transforming Growth Factor beta; Treatment Outcome; Vaccines, DNA; Viral Vaccines | 2018 |
13 other study(ies) available for transforming-growth-factor-beta and Prostatic-Neoplasms--Castration-Resistant
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Molecular classification of hormone-sensitive and castration-resistant prostate cancer, using nonnegative matrix factorization molecular subtyping of primary and metastatic specimens.
Despite the rapidly evolving therapeutic landscape, immunotherapy has demonstrated limited activity in prostate cancer. A greater understanding of the molecular landscape, particularly the expression of immune-related pathways, will inform future immunotherapeutic strategies. Consensus nonnegative matrix factorization (cNMF) is a novel model of molecular classification analyzing gene expression data, focusing on biological interpretation of metagenes and selecting meaningful clusters.. We aimed to identify molecular subtypes of prostate cancer using cNMF and correlate these with existing biomarkers to inform future immunotherapeutic strategies.. A cohort of archival tumor specimens from hormone-sensitive and castration-resistant disease was studied. Whole transcriptomic profiles were generated using TruSeq RNA Access technology and subjected to cNMF. Comprehensive genomic profiling was performed with the FoundationOne assay. NMF subtypes were characterized by gene expression pathways, genomic alterations and correlated with clinical data, then applied to The Cancer Genome Atlas data set.. We studied 164 specimens, including 52 castration-resistant and 13 paired primary/metastatic specimens. cNMF identified four distinct subtypes. NMF1 (19%) is enriched for immune-related and stromal-related pathways with transforming growth factor β (TGFβ) signature. NMF2 (36%) is associated with FOXO-mediated transcription signature and AKT signaling, NMF3 (26%) is enriched for ribosomal RNA processing, while NMF4 (19%) is enriched for cell cycle and DNA-repair pathways. The most common gene alterations included TMPRSS22 (42%), TP53 (23%), and DNA-repair genes (19%), occurring across all subtypes. NMF4 is significantly enriched for MYC and Wnt-signaling gene alterations. TMB, CD8 density, and PD-L1 expression were low overall. NMF1 and NMF4 were NMF2 was associated with superior overall survival.. Using cNMF, we identified four molecularly distinct subtypes which may inform treatment selection. NMF1 demonstrates the most inflammatory signature with asuppressive TGFβ signature, suggesting potential benefit with immunotherapy combination strategies targeting TGFβ and PD-(L)1. Prospective studies are required to evaluate the use of this novel model to molecularly stratify patients for optimal treatment selection. Topics: Biomarkers, Tumor; DNA; Genomics; Hormones; Humans; Male; Prostatic Neoplasms, Castration-Resistant; Transforming Growth Factor beta | 2022 |
The ubiquitin-ligase TRAF6 and TGFβ type I receptor form a complex with Aurora kinase B contributing to mitotic progression and cytokinesis in cancer cells.
Transforming growth factor β (TGFβ) is overexpressed in several advanced cancer types and promotes tumor progression. We have reported that the intracellular domain (ICD) of TGFβ receptor (TβR) I is cleaved by proteolytic enzymes in cancer cells, and then translocated to the nucleus in a manner dependent on the endosomal adaptor proteins APPL1/2, driving an invasiveness program. How cancer cells evade TGFβ-induced growth inhibition is unclear.. We performed microarray analysis to search for genes regulated by APPL1/2 proteins in castration-resistant prostate cancer (CRPC) cells. We investigated the role of TβRI and TRAF6 in mitosis in cancer cell lines cultured in 10% FBS in the absence of exogenous TGFβ. The molecular mechanism of the ubiquitination of AURKB by TRAF6 in mitosis and the formation of AURKB-TβRI complex in cancer cell lines and tissue microarrays was also studied.. During mitosis and cytokinesis, AURKB-TβRI complexes formed in midbodies in CRPC and KELLY neuroblastoma cells. TRAF6 induced polyubiquitination of AURKB on K85 and K87, protruding on the surface of AURKB to facilitate its activation. AURKB-TβRI complexes in patient's tumor tissue sections correlated with the malignancy of prostate cancer.. The AURKB-TβRI complex may become a prognostic biomarker for patients with risk of developing aggressive PC.. Swedish Medical Research Council (2019-01598, ML; 2015-02757 and 2020-01291, CHH), the Swedish Cancer Society (20 0964, ML), a regional agreement between Umeå University and Region Västerbotten (ALF; RV-939377, -967041, -970057, ML). The European Research Council (787472, CHH). KAW 2019.0345, and the Kempe Foundation SMK-1866; ML. National Microscopy Infrastructure (NMI VR-RFI 2016-00968). Topics: Aurora Kinase B; Cell Line, Tumor; Cytokinesis; Humans; Intracellular Signaling Peptides and Proteins; Ligases; Male; Prostatic Neoplasms, Castration-Resistant; Receptor, Transforming Growth Factor-beta Type I; TNF Receptor-Associated Factor 6; Transforming Growth Factor beta; Ubiquitin | 2022 |
Metformin regulates multiple signaling pathways within castration-resistant human prostate cancer cells.
The biguanide metformin has been shown to not only reduce circulating glucose levels but also suppress in vitro and in vivo growth of prostate cancer. However, the mechanisms underlying the anti-tumor effects of metformin in advanced prostate cancers are not fully understood. The goal of the present study was to define the signaling pathways regulated by metformin in androgen-receptor (AR) positive, castration-resistant prostate cancers.. Our group used RNA sequencing (RNA-seq) to examine genes regulated by metformin within the C4-2 human prostate cancer cell line. Western blot analysis and quantitative RT-PCR were used to confirm alterations in gene expression and further explore regulation of protein expression by metformin.. Data from the RNA-seq analysis revealed that metformin alters the expression of genes products involved in metabolic pathways, the spliceosome, RNA transport, and protein processing within the endoplasmic reticulum. Gene products involved in ErbB, insulin, mTOR, TGF-β, MAPK, and Wnt signaling pathways are also regulated by metformin. A subset of metformin-regulated gene products were genes known to be direct transcriptional targets of p53 or AR. Western blot analyses and quantitative RT-PCR indicated these alterations in gene expression are due in part to metformin-induced reductions in AR mRNA and protein levels.. Together, our results suggest metformin regulates multiple pathways linked to tumor growth and progression within advanced prostate cancer cells. Topics: Androgens; Castration; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Glucose; Humans; Insulins; Male; Metformin; Prostatic Neoplasms; Prostatic Neoplasms, Castration-Resistant; Receptors, Androgen; RNA, Messenger; TOR Serine-Threonine Kinases; Transforming Growth Factor beta; Tumor Suppressor Protein p53; Wnt Signaling Pathway | 2022 |
Acetylation of KLF5 maintains EMT and tumorigenicity to cause chemoresistant bone metastasis in prostate cancer.
Advanced prostate cancer (PCa) often develops bone metastasis, for which therapies are very limited and the underlying mechanisms are poorly understood. We report that bone-borne TGF-β induces the acetylation of transcription factor KLF5 in PCa bone metastases, and acetylated KLF5 (Ac-KLF5) causes osteoclastogenesis and bone metastatic lesions by activating CXCR4, which leads to IL-11 secretion, and stimulating SHH/IL-6 paracrine signaling. While essential for maintaining the mesenchymal phenotype and tumorigenicity, Ac-KLF5 also causes resistance to docetaxel in tumors and bone metastases, which is overcome by targeting CXCR4 with FDA-approved plerixafor. Establishing a mechanism for bone metastasis and chemoresistance in PCa, these findings provide a rationale for treating chemoresistant bone metastasis of PCa with inhibitors of Ac-KLF5/CXCR4 signaling. Topics: Acetylation; Animals; Antineoplastic Combined Chemotherapy Protocols; Benzylamines; Bone Neoplasms; Carcinogenesis; Cell Line, Tumor; Cyclams; Docetaxel; Epithelial-Mesenchymal Transition; Humans; Interleukin-11; Kruppel-Like Transcription Factors; Male; Mice; Mutation; Osteogenesis; Prostatic Neoplasms, Castration-Resistant; Receptors, CXCR4; Signal Transduction; Transforming Growth Factor beta | 2021 |
Differences in Tumor Microenvironment Dictate T Helper Lineage Polarization and Response to Immune Checkpoint Therapy.
Immune checkpoint therapy (ICT) shows encouraging results in a subset of patients with metastatic castration-resistant prostate cancer (mCRPC) but still elicits a sub-optimal response among those with bone metastases. Analysis of patients' bone marrow samples revealed increased T Topics: Animals; Antigens; Bone Neoplasms; Cell Lineage; Cell Proliferation; Clone Cells; CTLA-4 Antigen; Cytokines; Disease Models, Animal; Immunologic Memory; Immunotherapy; Ipilimumab; Male; Mice; Osteoclasts; Programmed Cell Death 1 Receptor; Prostatic Neoplasms, Castration-Resistant; Survival Analysis; T-Lymphocytes, Helper-Inducer; Th1 Cells; Transforming Growth Factor beta; Tumor Microenvironment | 2019 |
Re: Targeting FOXA1-Mediated Repression of TGF-β Signaling Suppresses Castration-Resistant Prostate Cancer Progression.
Topics: Disease Progression; Hepatocyte Nuclear Factor 3-alpha; Humans; Male; Prostatic Neoplasms; Prostatic Neoplasms, Castration-Resistant; Transforming Growth Factor beta | 2019 |
Sox5 contributes to prostate cancer metastasis and is a master regulator of TGF-β-induced epithelial mesenchymal transition through controlling Twist1 expression.
Metastatic castration-resistant prostate cancer (mCRPC) is one of the main contributors to the death of prostate cancer patients. To date, the detailed molecular mechanisms underlying mCRPC are unclear. Given the crucial role of epithelial-mesenchymal transition (EMT) in cancer metastasis, we aimed to analyse the expression and function of Transforming growth factor-beta (TGF-β) signal-associated protein named Sox5 in mCRPC.. The protein expression levels were analysed by western blot, immunohistochemistry and immunofluorescence. Luciferase reporter assays and chromatin immunoprecipitation were employed to validate the target of Sox5. The effect of Smad3/Sox5/Twist1 on PCa progression was investigated in vitro and in vivo.. Here, we found that TGF-β-induced EMT was accompanied by increased Sox5 expression. Interestingly, knockdown of Sox5 expression attenuated EMT induced by TGF-β signalling. Furthermore, we demonstrated that Smad3 could bind to the promoter of Sox5 and regulate its expression. Mechanistically, Sox5 could bind to Twist1 promoter and active Twist1, which initiated EMT. Importantly, knockdown of Sox5 in prostate cancer cells resulted in less of the mesenchymal phenotype and cell migration ability. Furthermore, targeting Sox5 could inhibit prostate cancer progression in a xenograft mouse model. In clinic, patients with high Sox5 expression were more likely to suffer from metastases, and high Sox5 expression also has a lower progression-free survival and cancer specific-survival in clinic database.. Therefore, we propose a new mechanism in which Smad3/Sox5/Twist1 promotes EMT and contributes to PCa progression. Topics: Animals; Cell Line, Tumor; Disease Progression; Epithelial-Mesenchymal Transition; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Humans; Male; Mice; Neoplasm Metastasis; Neoplasm Transplantation; Nuclear Proteins; Promoter Regions, Genetic; Prostatic Neoplasms, Castration-Resistant; Signal Transduction; Smad3 Protein; SOXD Transcription Factors; Survival Analysis; Transforming Growth Factor beta; Twist-Related Protein 1; Up-Regulation | 2018 |
Aberrant TGF-β Signaling Drives Castration-Resistant Prostate Cancer in a Male Mouse Model of Prostate Tumorigenesis.
The androgen receptor (AR) plays a critical role as a driver of castration-resistant prostate cancer (CRPC). Our previous studies demonstrated that disruption of transforming growth factor-β (TGF-β) signaling via introduction of dominant-negative transforming growth factor-β type II receptor (DNTGFβRII) in the prostate epithelium of transgenic adenocarcinoma of the prostate mice accelerated tumor. This study investigated the consequences of disrupted TGF-β signaling on prostate tumor growth under conditions of castration-induced androgen deprivation in the preclinical model of DNTGFβRII. Our results indicate that in response to androgen deprivation therapy (ADT) the proliferative index in prostate tumors from DNTGFβRII mice was higher compared with prostate tumors from TGFβRII wild-type (WT) mice, whereas there was a reduced incidence of apoptosis in tumors from DNTGFβRII. Protein and gene expression profiling revealed that tumors from DNTGFβRII mice exhibit a strong nuclear AR localization among the prostate tumor epithelial cells and increased AR messenger RNA after ADT. In contrast, TGFβRII WT mice exhibited a marked loss in nuclear AR in prostate tumor acini (20 weeks), followed by a downregulation of AR and transmembrane protease serine 2 messenger RNA. There was a significant increase in nuclear AR and activity in prostate tumors from castrate DNTGFβRII compared with TGFβRII WT mice. Consequential to aberrant TGF-β signaling, ADT enhanced expression and nuclear localization of Smad4 and β-catenin. Our findings support that under castrate conditions, aberrant TGF-β signaling leads to AR activation and β-catenin nuclear localization, an adaptation mechanism contributing to emergence of CRPC. The work defines a potentially significant new targeting platform for overcoming therapeutic resistance in CRPC. Topics: Animals; beta Catenin; Cell Transformation, Neoplastic; Disease Models, Animal; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Prostatic Neoplasms, Castration-Resistant; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Receptors, Tumor Necrosis Factor, Member 25; Signal Transduction; Transforming Growth Factor beta | 2017 |
Epithelial mesenchymal-like transition occurs in a subset of cells in castration resistant prostate cancer bone metastases.
TGFβ is a known driver of epithelial-mesenchymal transition (EMT) which is associated with tumor aggressiveness and metastasis. However, EMT has not been fully explored in clinical specimens of castration-resistant prostate cancer (CRPC) metastases. To assess EMT in CRPC, gene expression analysis was performed on 149 visceral and bone metastases from 62 CRPC patients and immunohistochemical analysis was performed on 185 CRPC bone and visceral metastases from 42 CRPC patients. In addition, to assess the potential of metastases to seed further metastases the mitochondrial genome was sequenced at different metastatic sites in one patient. TGFβ was increased in bone versus visceral metastases. While primarily cytoplasmic; nuclear and cytoplasmic Twist were significantly higher in bone than in visceral metastases. Slug and Zeb1 were unchanged, with the exception of nuclear Zeb1 being significantly higher in visceral metastases. Importantly, nuclear Twist, Slug, and Zeb1 were only present in a subset of epithelial cells that had an EMT-like phenotype. Underscoring the relevance of EMT-like cells, mitochondrial sequencing revealed that metastases could seed additional metastases in the same patient. In conclusion, while TGFβ expression and EMT-associated protein expression is present in a considerable number of CRPC visceral and bone metastases, nuclear Twist, Slug, and Zeb1 localization and an EMT-like phenotype (elongated nuclei and cytoplasmic compartment) was only present in a small subset of CRPC bone metastases. Mitochondrial sequencing from different metastases in a CRPC patient provided evidence for the seeding of metastases from previously established metastases, highlighting the biological relevance of EMT-like behavior in CRPC metastases. Topics: Bone Neoplasms; Epithelial-Mesenchymal Transition; Gene Expression Profiling; Homeodomain Proteins; Humans; Immunohistochemistry; Laser Capture Microdissection; Male; Neoplasm Metastasis; Nuclear Proteins; Prostatic Neoplasms, Castration-Resistant; Real-Time Polymerase Chain Reaction; Snail Family Transcription Factors; Tissue Array Analysis; Transcription Factors; Transcriptome; Transforming Growth Factor beta; Twist-Related Protein 1; Zinc Finger E-box-Binding Homeobox 1 | 2016 |
TGF-β signal rewiring sustains epithelial-mesenchymal transition of circulating tumor cells in prostate cancer xenograft hosts.
Activation of TGF-β signaling is known to promote epithelial-mesenchymal transition (EMT) for the development of metastatic castration-resistant prostate cancer (mCRPC). To determine whether targeting TGF-β signaling alone is sufficient to mitigate mCRPC, we used the CRISPR/Cas9 genome-editing approach to generate a dominant-negative mutation of the cognate receptor TGFBRII that attenuated TGF-β signaling in mCRPC cells. As a result, the delicate balance of oncogenic homeostasis is perturbed, profoundly uncoupling proliferative and metastatic potential of TGFBRII-edited tumor xenografts. This signaling disturbance triggered feedback rewiring by enhancing ERK signaling known to promote EMT-driven metastasis. Circulating tumor cells displaying upregulated EMT genes had elevated biophysical deformity and an increase in interactions with chaperone macrophages for facilitating metastatic extravasation. Treatment with an ERK inhibitor resulted in decreased aggressive features of CRPC cells in vitro. Therefore, combined targeting of TGF-β and its backup partner ERK represents an attractive strategy for treating mCRPC patients. Topics: Animals; Cell Line, Tumor; Cell Movement; Cell Proliferation; Epithelial-Mesenchymal Transition; Gene Editing; Humans; Male; MAP Kinase Signaling System; Mice; Neoplasm Transplantation; Neoplastic Cells, Circulating; Prostatic Neoplasms, Castration-Resistant; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Transforming Growth Factor beta | 2016 |
Activation of Akt signaling in prostate induces a TGFβ-mediated restraint on cancer progression and metastasis.
Mutations in the PTEN tumor suppressor gene are found in a high proportion of human prostate cancers, and in mice, Pten deletion induces high-grade prostate intraepithelial neoplasia (HGPIN). However, progression from HGPIN to invasive cancer occurs slowly, suggesting that tumorigenesis is subject to restraint. We show that Pten deletion, or constitutive activation of the downstream kinase AKT, activates the transforming growth factor (TGF)β pathway in prostate epithelial cells. TGFβ signaling is known to have a tumor suppressive role in many cancer types, and reduced expression of TGFβ receptors correlates with advanced human prostate cancer. We demonstrate that in combination either with loss of Pten or expression of constitutively active AKT1, inactivation of TGFβ signaling by deletion of the TGFβ type II receptor gene relieves a restraint on tumorigenesis. This results in rapid progession to lethal prostate cancer, including metastasis to lymph node and lung. In prostate epithelium, inactivation of TGFβ signaling alone is insufficient to initiate tumorigenesis, but greatly accelerates cancer progression. The activation of TGFβ signaling by Pten loss or AKT activation suggests that the same signaling events that have key roles in tumor initiation also induce the activity of a pathway that restrains disease progression. Topics: Adenocarcinoma; Animals; Disease Progression; Epithelial Cells; Gene Deletion; Homozygote; Humans; Lung Neoplasms; Lymphatic Metastasis; Male; Mice; Neoplasm Invasiveness; Prostate; Prostatic Neoplasms; Prostatic Neoplasms, Castration-Resistant; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Signal Transduction; Transforming Growth Factor beta | 2014 |
MED12 overexpression is a frequent event in castration-resistant prostate cancer.
In a recent effort to unravel the molecular basis of prostate cancer (PCa), Barbieri and colleagues using whole-exome sequencing identified a novel recurrently mutated gene, MED12, in 5.4% of primary PCa. MED12, encoding a subunit of the Mediator complex, is a transducer of Wnt/β-catenin signaling, linked to modulation of hedgehog signaling and to the regulation of transforming growth factor beta (TGFβ)-receptor signaling. Therefore, these studies prompted us to investigate the relevance of MED12 in PCa. Expression of MED12, SMAD3 phosphorylation, and proliferation markers was assessed by immunohistochemistry on tissue microarrays from 633 patients. siRNA-mediated knockdown of MED12 was carried out on PCa cell lines followed by cellular proliferation assays, cell cycle analysis, apoptosis assays, and treatments with recombinant TGFβ3. We found nuclear overexpression of MED12 in 40% (28/70) of distant metastatic castration-resistant prostate cancer (CRPC(MET)) and 21% (19/90) of local-recurrent CRPC (CRPC(LOC)) in comparison with frequencies of less than 11% in androgen-sensitive PCa, and no overexpression in benign prostatic tissues. MED12 expression was significantly correlated with high proliferative activity in PCa tissues, whereas knockdown of MED12 decreased proliferation, reduced G1- to S-phase transition, and increased the expression of the cell cycle inhibitor p27. TGFβ signaling activation associates with MED12 nuclear overexpression in tissues and results in a strong increase in MED12 nuclear expression in cell lines. Furthermore, MED12 knockdown reduced the expression of the TGFβ target gene vimentin. Our findings show that MED12 nuclear overexpression is a frequent event in CRPC in comparison with androgen-sensitive PCa and is directly implicated in TGFβ signaling. Topics: Cell Cycle; Cell Line, Tumor; Cell Proliferation; Humans; Male; Mediator Complex; Prostatic Neoplasms, Castration-Resistant; Signal Transduction; Smad3 Protein; Tissue Array Analysis; Transforming Growth Factor beta | 2014 |
Tissue injury and hypoxia promote malignant progression of prostate cancer by inducing CXCL13 expression in tumor myofibroblasts.
Prostate cancer (PC) is a slowly progressing malignancy that often responds to androgen ablation or chemotherapy by becoming more aggressive, acquiring a neuroendocrine phenotype, and undergoing metastatic spread. We found that B lymphocytes recruited into regressing androgen-deprived tumors by C-X-C motif chemokine 13 (CXCL13), a chemokine whose expression correlates with clinical severity, play an important role in malignant progression and metastatic dissemination of PC. We now describe how androgen ablation induces CXCL13 expression. In both allografted and spontaneous mouse PC, CXCL13 is expressed by tumor-associated myofibroblasts that are activated on androgen ablation through a hypoxia-dependent mechanism. The same cells produce CXCL13 after chemotherapy. Myofibroblast activation and CXCL13 expression also occur in the normal prostate after androgen deprivation, and CXCL13 is expressed by myofibroblasts in human PC. Hypoxia activates hypoxia-inducible factor 1 (HIF-1) and induces autocrine TGF-β signaling that promotes myofibroblast activation and CXCL13 induction. In addition to TGF-β receptor kinase inhibitors, myofibroblast activation and CXCL13 induction are blocked by phosphodiesterase 5 (PDE5) inhibitors. Both inhibitor types and myofibroblast immunodepletion block the emergence of castration-resistant PC in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of spontaneous metastatic PC with neuroendocrine differentiation. Topics: Adenocarcinoma; Androgens; Animals; Chemokine CXCL13; Connective Tissue Growth Factor; Disease Progression; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Insulin-Like Growth Factor I; Male; Mice, Transgenic; Myofibroblasts; Phosphodiesterase 5 Inhibitors; Prostate; Prostatic Neoplasms; Prostatic Neoplasms, Castration-Resistant; Receptors, Tumor Necrosis Factor, Member 25; Signal Transduction; Transforming Growth Factor beta | 2014 |