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1.
Development ; 150(13)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37376888

RESUMO

The reactivation of developmental genes and pathways during adulthood may contribute to pathogenesis of diseases such as prostate cancer. Analysis of the mechanistic links between development and disease could be exploited to identify signalling pathways leading to disease in the prostate. However, the mechanisms underpinning prostate development require further characterisation to interrogate fully the link between development and disease. Previously, our group developed methods to produce prostate organoids using induced pluripotent stem cells (iPSCs). Here, we show that human iPSCs can be differentiated into prostate organoids using neonatal rat seminal vesicle mesenchyme in vitro. The organoids can be used to study prostate development or modified to study prostate cancer. We also elucidated molecular drivers of prostate induction through RNA-sequencing analyses of the rat urogenital sinus and neonatal seminal vesicles. We identified candidate drivers of prostate development evident in the inductive mesenchyme and epithelium involved with prostate specification. Our top candidates included Spx, Trib3, Snai1, Snai2, Nrg2 and Lrp4. This work lays the foundations for further interrogation of the reactivation of developmental genes in adulthood, leading to prostate disease.


Assuntos
Células-Tronco Pluripotentes Induzidas , Neoplasias da Próstata , Masculino , Humanos , Ratos , Animais , Próstata , Roedores , Sistema Urogenital/fisiologia , Diferenciação Celular/genética , Organoides
2.
Br J Neurosurg ; : 1-4, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37158216

RESUMO

We describe the development of a direct traumatic arteriovenous fistula arising from the internal maxillary artery after an uneventful percutaneous trigeminal balloon compression for trigeminal neuralgia, and its management through embolization and radiosurgery.

3.
Nucleic Acids Res ; 48(10): 5366-5382, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32324216

RESUMO

Resistance to androgen receptor (AR) targeting therapeutics in prostate cancer (PC) is a significant clinical problem. Mechanisms by which this is accomplished include AR amplification and expression of AR splice variants, demonstrating that AR remains a key therapeutic target in advanced disease. For the first time we show that IKBKE drives AR signalling in advanced PC. Significant inhibition of AR regulated gene expression was observed upon siRNA-mediated IKBKE depletion or pharmacological inhibition due to inhibited AR gene expression in multiple cell line models including a LNCaP derivative cell line resistant to the anti-androgen, enzalutamide (LNCaP-EnzR). Phenotypically, this resulted in significant inhibition of proliferation, migration and colony forming ability suggesting that targeting IKBKE could circumvent resistance to AR targeting therapies. Indeed, pharmacological inhibition in the CWR22Rv1 xenograft mouse model reduced tumour size and enhanced survival. Critically, this was validated in patient-derived explants where enzymatic inactivation of IKBKE reduced cell proliferation and AR expression. Mechanistically, we provide evidence that IKBKE regulates AR levels via Hippo pathway inhibition to reduce c-MYC levels at cis-regulatory elements within the AR gene. Thus, IKBKE is a therapeutic target in advanced PC suggesting repurposing of clinically tested IKBKE inhibitors could be beneficial to castrate resistant PC patients.


Assuntos
Quinase I-kappa B/fisiologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Androgênicos/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Hippo , Humanos , Quinase I-kappa B/antagonistas & inibidores , Masculino , Camundongos Nus , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transcrição Gênica , Proteínas de Sinalização YAP
4.
Nucleic Acids Res ; 47(11): 5634-5647, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31006810

RESUMO

Resistance to androgen receptor (AR)-targeted therapies in prostate cancer (PC) is a major clinical problem. A key mechanism of treatment resistance in advanced PC is the generation of alternatively spliced forms of the AR termed AR variants (AR-Vs) that are refractory to targeted agents and drive tumour progression. Our understanding of how AR-Vs function is limited due to difficulties in distinguishing their discriminate activities from full-length AR (FL-AR). Here we report the development of a novel CRISPR-derived cell line which is a derivative of CWR22Rv1 cells, called CWR22Rv1-AR-EK, that has lost expression of FL-AR, but retains all endogenous AR-Vs. From this, we show that AR-Vs act unhindered by loss of FL-AR to drive cell growth and expression of androgenic genes. Global transcriptomics demonstrate that AR-Vs drive expression of a cohort of DNA damage response genes and depletion of AR-Vs sensitises cells to ionising radiation. Moreover, we demonstrate that AR-Vs interact with PARP1 and PARP2 and are dependent upon their catalytic function for transcriptional activation. Importantly, PARP blockade compromises expression of AR-V-target genes and reduces growth of CRPC cell lines suggesting a synthetic lethality relationship between AR-Vs and PARP, advocating the use of PARP inhibitors in AR-V positive PC.


Assuntos
Sistemas CRISPR-Cas , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Algoritmos , Linhagem Celular Tumoral , Proliferação de Células , Dano ao DNA , Reparo do DNA , Ensaios de Seleção de Medicamentos Antitumorais , Técnicas Genéticas , Humanos , Lentivirus , Masculino , Receptores Androgênicos/biossíntese , Análise de Sequência de RNA , Transcriptoma
5.
Br J Neurosurg ; 35(1): 80-83, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32419509

RESUMO

INTRODUCTION: The purpose of this paper is to report our experience of treating cerebral arteriovenous malformations (AVM) in adults with pre-operative embolisation and microsurgical resection on the same day during a single anaesthetic at a single centre between April 2016 and December 2018. We included both elective AVM and AVM that had bled acutely. METHODS: We retrospectively analysed data from patients with cerebral AVMs who underwent embolisation followed by microsurgical resection on the same day at a single neurosurgical centre. PRIMARY ENDPOINTS INCLUDED: Total procedure time (embolisation and microsurgical resection), procedure finish time, intra-operative blood loss, degree of nidus obliteration on postoperative angiography, intensive care unit (ICU) stay, total stay at the neurosurgical centre and modified Rankin Score (pre- and post-procedure). RESULTS: •Nineteen patients underwent same-day pre-operative embolisation and microsurgical resection over the 32-month period. The average patient age was 40 years (range 19-66 years). One patient had undergone a prior attempt at embolisation and one patient previously had sterotactic radiosurgery (STRS). •Thirteen of the AVM were in the dominant hemisphere and six in the non-dominant hemisphere. Sixteen AVM were located supratentorially and three were in the posterior fossa. Spetzler-Martin grades included 4 grade 1, 10 grade 2, 4 grade 3 and 1 grade 4. •The average blood loss intra-operatively was 289 mls. •The average list finish time was 19:56 (range 15:10-00:00). •Seventeen patients had 100% nidus obliteration on post-operative digital subtraction angiography, one patient had a small remnant and was referred to STRS and one patient died in the ICU post operatively. CONCLUSION: Overall, the authors believe same-day embolisation and microsurgical resection represents a safe treatment strategy. The technique minimises hemorrhagic complications from delayed venous occlusion and avoids multiple anaesthetics and hospital admissions.


Assuntos
Embolização Terapêutica , Malformações Arteriovenosas Intracranianas , Radiocirurgia , Adulto , Idoso , Encéfalo , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477471

RESUMO

Near real-time urban traffic analysis and prediction are paramount for effective intelligent transport systems. Whilst there is a plethora of research on advanced approaches to study traffic recently, only one-third of them has focused on urban arterials. A ready-to-use framework to support decision making in local traffic bureaus using largely available IoT sensors, especially CCTV, is yet to be developed. This study presents an end-to-end urban traffic volume detection and prediction framework using CCTV image series. The framework incorporates a novel Faster R-CNN to generate vehicle counts and quantify traffic conditions. Then it investigates the performance of a statistical-based model (SARIMAX), a machine learning (random forest; RF) and a deep learning (LSTM) model to predict traffic volume 30 min in the future. Tests at six locations with varying traffic conditions under different lengths of past time series are used to train the prediction models. RF and LSTM provided the most accurate predictions, with RF being faster than LSTM. The developed framework has been successfully applied to fill data gaps under adverse weather conditions when data are missing. It can be potentially implemented in near real time at any CCTV location and integrated into an online visualization platform.

7.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884905

RESUMO

The prostate is vulnerable to two major age-associated diseases, cancer and benign enlargement, which account for significant morbidity and mortality for men across the globe. Prostate cancer is the most common cancer reported in men, with over 1.2 million new cases diagnosed and 350,000 deaths recorded annually worldwide. Benign prostatic hyperplasia (BPH), characterised by the continuous enlargement of the adult prostate, symptomatically afflicts around 50% of men worldwide. A better understanding of the biological processes underpinning these diseases is needed to generate new treatment approaches. Developmental studies of the prostate have shed some light on the processes essential for prostate organogenesis, with many of these up- or downregulated genes expressions also observed in prostate cancer and/or BPH progression. These insights into human disease have been inferred through comparative biological studies relying primarily on rodent models. However, directly observing mechanisms of human prostate development has been more challenging due to limitations in accessing human foetal material. Induced pluripotent stem cells (iPSCs) could provide a suitable alternative as they can mimic embryonic cells, and iPSC-derived prostate organoids present a significant opportunity to study early human prostate developmental processes. In this review, we discuss the current understanding of prostate development and its relevance to prostate-associated diseases. Additionally, we detail the potential of iPSC-derived prostate organoids for studying human prostate development and disease.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Próstata/crescimento & desenvolvimento , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Organogênese , Próstata/citologia , Próstata/patologia , Técnicas de Cultura de Tecidos
8.
Nucleic Acids Res ; 45(4): 1793-1804, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-27903893

RESUMO

The androgen receptor (AR) is the main driver of prostate cancer (PC) development and progression, and the primary therapeutic target in PC. To date, two functional ubiquitination sites have been identified on AR, both located in its C-terminal ligand binding domain (LBD). Recent reports highlight the emergence of AR splice variants lacking the LBD that can arise during disease progression and contribute to castrate resistance. Here, we report a novel N-terminal ubiquitination site at lysine 311. Ubiquitination of this site plays a role in AR stability and is critical for its transcriptional activity. Inactivation of this site causes AR to accumulate on chromatin and inactivates its transcriptional function as a consequence of inability to bind to p300. Additionally, mutation at lysine 311 affects cellular transcriptome altering the expression of genes involved in chromatin organization, signaling, adhesion, motility, development and metabolism. Even though this site is present in clinically relevant AR-variants it can only be ubiquitinated in cells when AR retains LBD suggesting a role for AR C-terminus in E2/E3 substrate recognition. We report that as a consequence AR variants lacking the LBD cannot be ubiquitinated in the cellular environment and their protein turnover must be regulated via an alternate pathway.


Assuntos
Receptores Androgênicos/metabolismo , Ativação Transcricional , Ubiquitinação , Aminoácidos/metabolismo , Animais , Linhagem Celular Tumoral , Cromatina/metabolismo , Análise por Conglomerados , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Mutação , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estabilidade Proteica , Proteoma , Proteômica/métodos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Receptores Androgênicos/química , Receptores Androgênicos/genética , Transcrição Gênica , Transcriptoma
9.
Br J Cancer ; 118(5): 713-726, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29381681

RESUMO

BACKGROUND: Although the founding members of the INhibitor of Growth (ING) family of histone mark readers, ING1 and ING2, were defined as tumour suppressors in animal models, the role of other ING proteins in cellular proliferation and cancer progression is unclear. METHODS: We transduced ex vivo benign prostate hyperplasia tissues with inducible lentiviral particles to express ING proteins. Proliferation was assessed by H3S10phos immunohistochemistry (IHC). The expression of ING3 was assessed by IHC on a human prostate cancer tissue microarray (TMA). Gene expression was measured by DNA microarray and validated by real-time qPCR. RESULTS: We found that ING3 stimulates cellular proliferation in ex vivo tissues, suggesting that ING3 could be oncogenic. Indeed, ING3 overexpression transformed normal human dermal fibroblasts. We observed elevated levels of ING3 in prostate cancer samples, which correlated with poorer patient survival. Consistent with an oncogenic role, gene-silencing experiments revealed that ING3 is required for the proliferation of breast, ovarian, and prostate cancer cells. Finally, ING3 controls the expression of an intricate network of cell cycle genes by associating with chromatin modifiers and the H3K4me3 mark at transcriptional start sites. CONCLUSIONS: Our investigations create a shift in the prevailing view that ING proteins are tumour suppressors and redefine ING3 as an oncoprotein.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Hiperplasia Prostática/genética , Neoplasias da Próstata/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ciclo Celular , Linhagem Celular , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Progressão da Doença , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Lentivirus/genética , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Análise Serial de Tecidos , Transdução Genética , Regulação para Cima
11.
Br J Neurosurg ; 32(6): 592-594, 2018 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-30392385

RESUMO

BACKGROUND: Unintended durotomy is a well-recognised complication of lumbar spine surgery. Reported complications include headaches, intracranial haematomata, pseudomeningocoele and infection. Methods of intraoperative repair vary and although post-operative flat bed rest is advocated by some, there is no consensus on duration. We reviewed a series of unintended durotomies that occurred in our institution and reviewed them to compare management strategies and outcome. METHODS: A retrospective analysis was conducted of adult patients who experienced an unintended durotomy during surgery for lumbar degenerative disease in our neurosurgical unit over a 15-month period. Post-operative complications were followed up for a minimum of 3 months. RESULTS: 1125 patients underwent elective or emergency decompressive lumbar spine surgery. 45 (4%) dural tears were identified; all were repaired intra-operatively with suturing, Tisseal thrombin glue or both. Absence of leakage was confirmed on Valsalva manoeuvre for all cases, before wound closure. 28 patients were mobilised within 24 hrs of surgery, 16 patients between 24-48 hours and 1 patient after 48 hours. Seven patients (16%) with a dural tear experienced a complication. There was no statistically significant relationship between time to post-operative mobilisation and complication rate (p = .76). There was a significantly longer inpatient stay when patients were on bed rest for longer (2 tailed test significant at the 2% level). CONCLUSION: Duration of post-operative bed rest was not related to complication rate but led to delays in discharge. We did not find evidence that early mobilisation lead to increased likelihood of complications.

12.
J Biol Chem ; 291(35): 18326-41, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27281824

RESUMO

Aberrant access to genetic information disrupts cellular homeostasis and can lead to cancer development. One molecular mechanism that regulates access to genetic information includes recognition of histone modifications, which is carried out by protein modules that interact with chromatin and serve as landing pads for enzymatic activities that regulate gene expression. The ING3 tumor suppressor protein contains a plant homeodomain (PHD) that reads the epigenetic code via recognition of histone H3 tri-methylated at lysine 4 (H3K4me3), and this domain is lost or mutated in various human cancers. However, the molecular mechanisms targeting ING3 to histones and the role of this interaction in the cell remain elusive. Thus, we employed biochemical and structural biology approaches to investigate the interaction of the ING3 PHD finger (ING3PHD) with the active transcription mark H3K4me3. Our results demonstrate that association of the ING3PHD with H3K4me3 is in the sub-micromolar range (KD ranging between 0.63 and 0.93 µm) and is about 200-fold stronger than with the unmodified histone H3. NMR and computational studies revealed an aromatic cage composed of Tyr-362, Ser-369, and Trp-385 that accommodate the tri-methylated side chain of H3K4. Mutational analysis confirmed the critical importance of Tyr-362 and Trp-385 in mediating the ING3PHD-H3K4me3 interaction. Finally, the biological relevance of ING3PHD-H3K4me3 binding was demonstrated by the failure of ING3PHD mutant proteins to enhance ING3-mediated DNA damage-dependent cell death. Together, our results reveal the molecular mechanism of H3K4me3 selection by the ING3PHD and suggest that this interaction is important for mediating ING3 tumor suppressive activities.


Assuntos
Histonas/química , Proteínas de Homeodomínio/química , Proteínas Supressoras de Tumor/química , Substituição de Aminoácidos , Morte Celular , Dano ao DNA , Epigênese Genética , Histonas/genética , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Metilação , Mutação de Sentido Incorreto , Ressonância Magnética Nuclear Biomolecular , Domínios RING Finger , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
13.
Nucleic Acids Res ; 43(1): 196-207, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25488809

RESUMO

Endocrine therapy has successfully been used to treat estrogen receptor (ER)-positive breast cancer, but this invariably fails with cancers becoming refractory to treatment. Emerging evidence has suggested that fluctuations in ER co-regulatory protein expression may facilitate resistance to therapy and be involved in breast cancer progression. To date, a small number of enzymes that control methylation status of histones have been identified as co-regulators of ER signalling. We have identified the histone H3 lysine 9 mono- and di-methyl demethylase enzyme KDM3A as a positive regulator of ER activity. Here, we demonstrate that depletion of KDM3A by RNAi abrogates the recruitment of the ER to cis-regulatory elements within target gene promoters, thereby inhibiting estrogen-induced gene expression changes. Global gene expression analysis of KDM3A-depleted cells identified gene clusters associated with cell growth. Consistent with this, we show that knockdown of KDM3A reduces ER-positive cell proliferation and demonstrate that KDM3A is required for growth in a model of endocrine therapy-resistant disease. Crucially, we show that KDM3A catalytic activity is required for both ER-target gene expression and cell growth, demonstrating that developing compounds which target demethylase enzymatic activity may be efficacious in treating both ER-positive and endocrine therapy-resistant disease.


Assuntos
Neoplasias da Mama/enzimologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Histona Desmetilases com o Domínio Jumonji/fisiologia , Células MCF-7 , Elementos de Resposta , Transdução de Sinais
14.
J Pathol ; 235(4): 581-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25408555

RESUMO

Biomechanical strain imposed by age-related thickening of the basal lamina and augmented tissue stiffness in the prostate gland coincides with increased cancer risk. Here we hypothesized that the structural alterations in the basal lamina associated with age can induce mechanotransduction pathways in prostate epithelial cells (PECs) to promote invasiveness and cancer progression. To demonstrate this, we developed a 3D model of PEC acini in which thickening and stiffening of basal lamina matrix was induced by advanced glycation end-product (AGE)-dependent non-enzymatic crosslinking of its major components, collagen IV and laminin. We used this model to demonstrate that antibody targeted blockade of CTLD2, the second of eight C-type lectin-like domains in Endo180 (CD280, CLEC13E, KIAA0709, MRC2, TEM9, uPARAP) that can recognize glycosylated collagens, reversed actinomyosin-based contractility [myosin-light chain-2 (MLC2) phosphorylation], loss of cell polarity, loss of cell-cell junctions, luminal infiltration and basal invasion induced by AGE-modified basal lamina matrix in PEC acini. Our in vitro results were concordant with luminal occlusion of acini in the prostate glands of adult Endo180(Δ) (Ex2-6/) (Δ) (Ex2-6) mice, with constitutively exposed CTLD2 and decreased survival of men with early (non-invasive) prostate cancer with high epithelial Endo180 expression and levels of AGE. These findings indicate that AGE-dependent modification of the basal lamina induces invasive behaviour in non-transformed PECs via a molecular mechanism linked to cancer progression. This study provides a rationale for targeting CTLD2 in Endo180 in prostate cancer and other pathologies in which increased basal lamina thickness and tissue stiffness are driving factors. © 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Membrana Basal/metabolismo , Movimento Celular , Células Epiteliais/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Lectinas de Ligação a Manose/metabolismo , Glicoproteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Mitogênicos/metabolismo , Animais , Membrana Basal/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Elasticidade , Humanos , Estimativa de Kaplan-Meier , Lectinas Tipo C/metabolismo , Masculino , Mecanotransdução Celular , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos Knockout , Invasividade Neoplásica , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estrutura Terciária de Proteína , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Fatores de Tempo
15.
BMC Cancer ; 15: 9, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25592066

RESUMO

BACKGROUND: Androgens drive the onset and progression of prostate cancer (PCa) via androgen receptor (AR) signalling. The principal treatment for PCa is androgen deprivation therapy, although the majority of patients eventually develop a lethal castrate-resistant form of the disease, where despite low serum testosterone levels AR signalling persists. Advanced PCa often has hyper-activated RAS/ERK1/2 signalling thought to be due to loss of function of key negative regulators of the pathway, the details of which are not fully understood. METHODS: We recently carried out a genome-wide study and identified a subset of 226 novel androgen-regulated genes (PLOS ONE 6:e29088, 2011). In this study we have meta-analysed this dataset with genes and pathways frequently mutated in PCa to identify androgen-responsive regulators of the RAS/ERK1/2 pathway. RESULTS: We find the PTGER4 and TSPYL2 genes are up-regulated by androgen stimulation and the ADCY1, OPKR1, TRIB1, SPRY1 and PTPRR are down-regulated by androgens. Further characterisation of PTPRR protein in LNCaP cells revealed it is an early and direct target of the androgen receptor which negatively regulates the RAS/ERK1/2 pathway and reduces cell proliferation in response to androgens. CONCLUSION: Our data suggest that loss of PTPRR in clinical PCa is one factor that might contribute to activation of the RAS/ERK1/2 pathway.


Assuntos
Androgênios/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias da Próstata/genética , Proteínas Tirosina Fosfatases Classe 7 Semelhantes a Receptores/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Proteínas Tirosina Fosfatases Classe 7 Semelhantes a Receptores/metabolismo , Receptores Androgênicos/metabolismo
16.
Nucleic Acids Res ; 41(14): 6892-904, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23723241

RESUMO

The importance of the estrogen receptor (ER) in breast cancer (BCa) development makes it a prominent target for therapy. Current treatments, however, have limited effectiveness, and hence the definition of new therapeutic targets is vital. The ER is a member of the nuclear hormone receptor superfamily of transcription factors that requires co-regulator proteins for complete regulation. Emerging evidence has implicated a small number of histone methyltransferase (HMT) and histone demethylase (HDM) enzymes as regulators of ER signalling, including the histone H3 lysine 9 tri-/di-methyl HDM enzyme KDM4B. Two recent independent reports have demonstrated that KDM4B is required for ER-mediated transcription and depletion of the enzyme attenuates BCa growth in vitro and in vivo. Here we show that KDM4B has an overarching regulatory role in the ER signalling cascade by controlling expression of the ER and FOXA1 genes, two critical components for maintenance of the estrogen-dependent phenotype. KDM4B interacts with the transcription factor GATA-3 in BCa cell lines and directly co-activates GATA-3 activity in reporter-based experiments. Moreover, we reveal that KDM4B recruitment and demethylation of repressive H3K9me3 marks within upstream regulatory regions of the ER gene permits binding of GATA-3 to drive receptor expression. Ultimately, our findings confirm the importance of KDM4B within the ER signalling cascade and as a potential therapeutic target for BCa treatment.


Assuntos
Histona Desmetilases com o Domínio Jumonji/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais , Linhagem Celular , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/fisiologia , Células MCF-7 , Receptores de Estrogênio/genética , Elementos Reguladores de Transcrição
17.
Nucleic Acids Res ; 41(8): 4433-46, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23435229

RESUMO

The androgen receptor (AR) is a key molecule involved in prostate cancer (PC) development and progression. Post-translational modification of the AR by co-regulator proteins can modulate its transcriptional activity. To identify which demethylases might be involved in AR regulation, an siRNA screen was performed to reveal that the demethylase, KDM4B, may be an important co-regulator protein. KDM4B enzymatic activity is required to enhance AR transcriptional activity; however, independently of this activity, KDM4B can enhance AR protein stability via inhibition of AR ubiquitination. Importantly, knockdown of KDM4B in multiple cell lines results in almost complete depletion of AR protein levels. For the first time, we have identified KDM4B to be an androgen-regulated demethylase enzyme, which can influence AR transcriptional activity not only via demethylation activity but also via modulation of ubiquitination. Together, these findings demonstrate the close functional relationship between AR and KDM4B, which work together to amplify the androgen response. Furthermore, KDM4B expression in clinical PC specimens positively correlates with increasing cancer grade (P < 0.001). Consequently, KDM4B is a viable therapeutic target in PC.


Assuntos
Histona Desmetilases com o Domínio Jumonji/metabolismo , Receptores Androgênicos/metabolismo , Androgênios/farmacologia , Animais , Linhagem Celular , Proliferação de Células , Regulação da Expressão Gênica , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/fisiologia , Masculino , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Processamento de Proteína Pós-Traducional , Estabilidade Proteica , Transdução de Sinais , Transcrição Gênica , Ubiquitinação
18.
J Biol Chem ; 288(45): 32641-32650, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24056413

RESUMO

The androgen receptor (AR), a member of the nuclear receptor family, is a transcription factor involved in prostate cell growth, homeostasis, and transformation. AR is a key protein in growth and development of both normal and malignant prostate, making it a common therapeutic target in prostate cancer. AR is regulated by an interplay of multiple post-translational modifications including ubiquitination. We and others have shown that the AR is ubiquitinated by a number of E3 ubiquitin ligases, including MDM2, CHIP, and NEDD4, which can result in its proteosomal degradation or enhanced transcriptional activity. As ubiquitination of AR causes a change in AR activity or stability and impacts both survival and growth of prostate cancer cells, deubiquitination of these sites has an equally important role. Hence, deubiquitinating enzymes could offer novel therapeutic targets. We performed an siRNA screen to identify deubiquitinating enzymes that regulate AR; in that screen ubiquitin-specific protease 12 (Usp12) was identified as a novel positive regulator of AR. Usp12 is a poorly characterized protein with few known functions and requires the interaction with two cofactors, Uaf-1 and WDR20, for its enzymatic activity. In this report we demonstrate that Usp12, in complex with Uaf-1 and WDR20, deubiquitinates the AR to enhance receptor stability and transcriptional activity. Our data show that Usp12 acts in a pro-proliferative manner by stabilizing AR and enhancing its cellular function.


Assuntos
Proliferação de Células , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Ubiquitina Tiolesterase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Animais , Células COS , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Chlorocebus aethiops , Humanos , Masculino , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/genética , Estabilidade Proteica , Receptores Androgênicos/genética , Ubiquitina Tiolesterase/genética , Ubiquitina-Proteína Ligases/genética
19.
BMC Cancer ; 14: 977, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25519703

RESUMO

BACKGROUND: Although chemotherapy for prostate cancer (PCa) can improve patient survival, some tumours are chemo-resistant. Tumour molecular profiles may help identify the mechanisms of drug action and identify potential prognostic biomarkers. We performed in vivo transcriptome profiling of pre- and post-treatment prostatic biopsies from patients with advanced hormone-naive prostate cancer treated with docetaxel chemotherapy and androgen deprivation therapy (ADT) with an aim to identify the mechanisms of drug action and identify prognostic biomarkers. METHODS: RNA sequencing (RNA-Seq) was performed on biopsies from four patients before and ~22 weeks after docetaxel and ADT initiation. Gene fusion products and differentially-regulated genes between treatment pairs were identified using TopHat and pathway enrichment analyses undertaken. Publically available datasets were interrogated to perform survival analyses on the gene signatures identified using cBioportal. RESULTS: A number of genomic rearrangements were identified including the TMPRSS2/ERG fusion and 3 novel gene fusions involving the ETS family of transcription factors in patients, both pre and post chemotherapy. In total, gene expression analyses showed differential expression of at least 2 fold in 575 genes in post-chemotherapy biopsies. Of these, pathway analyses identified a panel of 7 genes (ADAM7, FAM72B, BUB1B, CCNB1, CCNB2, TTK, CDK1), including a cell cycle-related geneset, that were differentially-regulated following treatment with docetaxel and ADT. Using cBioportal to interrogate the MSKCC-Prostate Oncogenome Project dataset we observed a statistically-significant reduction in disease-free survival of patients with tumours exhibiting alterations in gene expression of the above panel of 7 genes (p = 0.015). CONCLUSIONS: Here we report on the first "real-time" in vivo RNA-Seq-based transcriptome analysis of clinical PCa from pre- and post-treatment TRUSS-guided biopsies of patients treated with docetaxel chemotherapy plus ADT. We identify a chemotherapy-driven PCa transcriptome profile which includes the down-regulation of important positive regulators of cell cycle progression. A 7 gene signature biomarker panel has also been identified in high-risk prostate cancer patients to be of prognostic value. Future prospective study is warranted to evaluate the clinical value of this panel.


Assuntos
Perfilação da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/mortalidade , Transcriptoma , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia
20.
Br J Neurosurg ; 28(3): 408-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24564244

RESUMO

Klippel-Feil syndrome (KPS) is a congenital spinal deformity characterised by the presence of at least one fused cervical segment. We report an unusual case of a fracture through fused cervical segment in a patient with KPS, who presented with quadriparesis and progressed on to develop respiratory failure and quadriplegia and who had a successful outcome following surgery. To the best of our knowledge, fracture through fused cervical segments in a Klippel-Feil patient has not been reported previously and this case report extends the spectrum of injuries seen in patients with KPS.


Assuntos
Vértebras Cervicais/lesões , Vértebras Cervicais/cirurgia , Síndrome de Klippel-Feil/complicações , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral , Fixação Intramedular de Fraturas , Humanos , Masculino , Quadriplegia/etiologia , Resultado do Tratamento , Adulto Jovem
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