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1.
Cell ; 165(3): 643-55, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27104980

RESUMO

Oncogenic activation of RAS genes via point mutations occurs in 20%-30% of human cancers. The development of effective RAS inhibitors has been challenging, necessitating new approaches to inhibit this oncogenic protein. Functional studies have shown that the switch region of RAS interacts with a large number of effector proteins containing a common RAS-binding domain (RBD). Because RBD-mediated interactions are essential for RAS signaling, blocking RBD association with small molecules constitutes an attractive therapeutic approach. Here, we present evidence that rigosertib, a styryl-benzyl sulfone, acts as a RAS-mimetic and interacts with the RBDs of RAF kinases, resulting in their inability to bind to RAS, disruption of RAF activation, and inhibition of the RAS-RAF-MEK pathway. We also find that ribosertib binds to the RBDs of Ral-GDS and PI3Ks. These results suggest that targeting of RBDs across multiple signaling pathways by rigosertib may represent an effective strategy for inactivation of RAS signaling.


Assuntos
Glicina/análogos & derivados , Proteínas de Ligação a RNA/química , Transdução de Sinais/efeitos dos fármacos , Sulfonas/farmacologia , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Cristalografia por Raios X , Dimerização , Glicina/administração & dosagem , Glicina/química , Glicina/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Nus , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Neoplasias Pancreáticas/tratamento farmacológico , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas B-raf/química , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência , Sulfonas/administração & dosagem , Sulfonas/química , Proteínas ras/metabolismo , Quinase 1 Polo-Like
2.
Carcinogenesis ; 43(6): 528-537, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35239955

RESUMO

There is increased incidence of prostate cancer (PC) among World Trade Center (WTC)-exposed responders and community members, with preliminary evidence suggestive of more aggressive disease. While previous research is supportive of differences in DNA methylation and gene expression as a consequence of WTC exposure, as measured in blood of healthy individuals, the epigenetics of WTC PC tissues has yet to be explored. Patients were recruited from the World Trade Center Health Program. Non-WTC PC samples were frequency matched on age, race/ethnicity and Gleason score. Bisulfite-treated DNA was extracted from tumor tissue blocks and used to assess global DNA methylation with the MethylationEPIC BeadChip. Differential and pathway enrichment analyses were conducted. RNA from the same tumor blocks was used for gene expression analysis to further support DNA methylation findings. Methylation data were generated for 28 samples (13 WTC and 15 non-WTC). Statistically significant differences in methylation were observed for 3,586 genes; on average WTC samples were statistically significantly more hypermethylated (P = 0.04131). Pathway enrichment analysis revealed hypermethylation in epithelial mesenchymal transition (EMT), hypoxia, mitotic spindle, TNFA signaling via NFKB, WNT signaling, and TGF beta signaling pathways in WTC compared to non-WTC samples. The androgen response, G2M and MYC target pathways were hypomethylated. These results correlated well with RNA gene expression. In conclusion, long-term epigenic changes associated with WTC dust exposure were observed in PC tissues. These occurred in genes of critical pathways, likely increasing prostate tumorigenesis potential. This warrants analysis of larger WTC groups and other cancer types.


Assuntos
Neoplasias da Próstata , Ataques Terroristas de 11 de Setembro , Metilação de DNA/genética , Poeira , Humanos , Masculino , Neoplasias da Próstata/genética , RNA
3.
J Transl Med ; 17(1): 342, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601237

RESUMO

World Trade Center (WTC) responders were exposed to mixture of dust, smoke, chemicals and carcinogens. New York University (NYU) and Mount Sinai have recreated WTC exposure in rodents to observe the resulting systemic and local biological responses. These experiments aid in the interpretation of epidemiological observations and are useful for understanding the carcinogenesis process in the exposed human WTC cohort. Here we describe the implementation of a tissue bank system for the rodents experimentally exposed to WTC dust. NYU samples were experimentally exposed to WTC dust via intratracheal inhalation that mimicked conditions in the immediate aftermath of the disaster. Tissue from Mount Sinai was derived from genetically modified mice exposed to WTC dust via nasal instillation. All processed tissues include annotations of the experimental design, WTC dust concentration/dose, exposure route and duration, genetic background of the rodent, and method of tissue isolation/storage. A biobank of tissue from rodents exposed to WTC dust has been compiled representing an important resource for the scientific community. The biobank remains available as a scientific resource for future research through established mechanisms for samples request and utilization. Studies using the WTC tissue bank would benefit from confirming their findings in corresponding tissues from organs of animals experimentally exposed to WTC dust. Studies on rodent tissues will advance the understanding of the biology of the tumors developed by WTC responders and ultimately impact the modalities of treatment, and the probability of success and survival of WTC cancer patients.


Assuntos
Bancos de Espécimes Biológicos , Carcinogênese/patologia , Neoplasias/patologia , Animais , Poeira , Masculino , Camundongos Endogâmicos C57BL , Ratos Endogâmicos SHR , Ataques Terroristas de 11 de Setembro
4.
Int J Mol Sci ; 18(7)2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28714919

RESUMO

Immunotherapy is being tested intensively in clinical trials for prostate cancer; it includes immune checkpoint inhibition, prostate specific antigen (PSA) vaccines and dendritic cell-based strategies. Despite increasing evidence for clinical responses, the consensus of multiple trials is that prostate cancers are poorly responsive to immunotherapy. Prostate cancer has a high degree of pathological and genetic heterogeneity compared to other cancer types, which may account for immunotherapeutic resistance. This hypothesis also implies that select types of prostate tumors may be differentially responsive to immune-based strategies and that the clinical stage, pathological grade and underlying genetic landscape may be important criteria in identifying tumors that respond to immune therapies. One strategy is to target oncogenic driver pathways in combination with immunotherapies with the goal of overcoming tumor immunity and broadening the number of patients achieving a clinical response. In this analysis, we address the hypothesis that driver oncogenic signaling pathways regulate cancer progression, tumor immunity and resistance to current immune therapeutics in prostate cancer. We propose that increased responsiveness may be achieved through the combined use of immunotherapies and inhibitors targeting tumor cell autonomous pathways that contribute towards anti-tumor immunity in patients with prostate cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Oncogênicas/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Imunoterapia/métodos , Masculino , Terapia de Alvo Molecular/métodos , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
5.
Neuroepidemiology ; 45(1): 34-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26201454

RESUMO

BACKGROUND: There is limited literature on the epidemiology of idiopathic intracranial hypertension (IIH). The diagnosis and management of IIH require a multidisciplinary approach. We sought to study the incidence as well as prevalence of IIH and to evaluate the current management of IIH in the northwest of Northern Ireland. METHODS: Medical records of patients diagnosed with IIH between 2007 and 2014 in a general hospital in Northern Ireland were reviewed. Clinical and outcome data were retrieved. RESULTS: There were 45 patients with IIH, 44 women: 1 man. The mean age at presentation was 29.4 (SD 9.8) years and mean body mass index (BMI) 39.8 (SD 9.5) kg/ m(2). All patients had neuroimaging, 44 (98%) had CT/MR venogram and 41 (91%) had visual perimetry. The crude incidence of IIH was 2.36 per 100,000 (95% CI 1.65-3.37). For women, the incidence was 4.65 per 100,000/year (95% CI 3.25-6.66). The prevalence was 14.3 per 100,000 overall (95% CI 9.72-20.9) but 28.1 per 100,000 in women (95% CI 19.2-41.2). Visual field defects were identified in 25 of 41 (61%); 4 patients (9%) required shunting procedures. At follow-up, the mean BMI decreased by 1.6 kg/m(2) (p = 0.024). CONCLUSIONS: The incidence of IIH in the northwest of Northern Ireland is among the highest ever reported and probably reflects the known increase in obesity.


Assuntos
Pseudotumor Cerebral/epidemiologia , Adolescente , Adulto , Feminino , Humanos , Incidência , Irlanda , Masculino , Prevalência , Pseudotumor Cerebral/terapia , Adulto Jovem
6.
Cancer Cell ; 12(6): 572-85, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18068633

RESUMO

Enhanced mesenchymal expression of FGF10 led to the formation of multifocal PIN or prostate cancer. Inhibition of epithelial FGFR1 signaling using DN FGFR1 led to reversal of the cancer phenotype. A subset of the FGF10-induced carcinoma was serially transplantable. Paracrine FGF10 led to an increase in epithelial androgen receptor and synergized with cell-autonomous activated AKT. Our observations indicate that stromal FGF10 expression may facilitate the multifocal histology observed in prostate adenocarcinoma and suggest the FGF10/FGFR1 axis as a potential therapeutic target in treating hormone-sensitive or refractory prostate cancer. We also show that transient exposure to a paracrine growth factor may be sufficient for the initiation of oncogenic transformation.


Assuntos
Células Epiteliais/metabolismo , Fator 10 de Crescimento de Fibroblastos/metabolismo , Comunicação Parácrina , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Transformação Celular Neoplásica , Ativação Enzimática , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Epitélio/patologia , Genes Dominantes , Masculino , Mesoderma/patologia , Camundongos , Transplante de Neoplasias , Especificidade de Órgãos , Neoplasia Prostática Intraepitelial/enzimologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Regeneração
7.
Proc Natl Acad Sci U S A ; 109(30): 12046-51, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22753496

RESUMO

The c-Jun NH(2)-terminal kinase (JNK) signal transduction pathway is implicated in cancer, but the role of JNK in tumorigenesis is poorly understood. Here, we demonstrate that the JNK signaling pathway reduces the development of invasive adenocarcinoma in the phosphatase and tensin homolog (Pten) conditional deletion model of prostate cancer. Mice with JNK deficiency in the prostate epithelium (ΔJnk ΔPten mice) develop androgen-independent metastatic prostate cancer more rapidly than control (ΔPten) mice. Similarly, prevention of JNK activation in the prostate epithelium (ΔMkk4 ΔMkk7 ΔPten mice) causes rapid development of invasive adenocarcinoma. We found that JNK signaling defects cause an androgen-independent expansion of the immature progenitor cell population in the primary tumor. The JNK-deficient progenitor cells display increased proliferation and tumorigenic potential compared with progenitor cells from control prostate tumors. These data demonstrate that the JNK and PTEN signaling pathways can cooperate to regulate the progression of prostate neoplasia to invasive adenocarcinoma.


Assuntos
Adenocarcinoma/fisiopatologia , Transformação Celular Neoplásica/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/fisiopatologia , Animais , Técnicas Histológicas , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência
8.
Carcinogenesis ; 35(10): 2321-30, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25023990

RESUMO

Prostate cancer (PCa) is the second cause of cancer deaths in men in the USA. When the cancer recurs, early stages can be controlled with hormone ablation therapy to delay the rate of cancer progression but, over time, the cancer overcomes its hormone dependence, becomes highly aggressive and metastasizes. Clinical trials have shown that pomegranate juice (PJ) inhibits PCa progression. We have previously shown that the PJ components luteolin (L), ellagic acid (E) and punicic acid (P) together inhibit growth of hormone-dependent and -independent PCa cells and inhibit their migration and chemotaxis towards CXCL12, a chemokine that is important in PCa metastasis. On the basis of these findings, we hypothesized that L+E+P inhibit PCa metastasis in vivo. To test this possibility, we used a severe combined immunodeficiency mouse model in which luciferase-expressing human PCa cells were injected subcutaneously near the prostate. Tumor progression was monitored with bioluminescence imaging weekly. We found that L+E+P inhibits PC-3M-luc primary tumor growth, inhibits the CXCL12/CXCR4 axis for metastasis and none of the tumors metastasized. In addition, L+E+P significantly inhibits growth and metastasis of highly invasive Pten (-/-) ;K-ras (G12D) prostate tumors. Furthermore, L+E+P inhibits angiogenesis in vivo, prevents human endothelial cell (EC) tube formation in culture and disrupts preformed EC tubes, indicating inhibition of EC adhesion to each other. L+E+P also inhibits the angiogenic factors interleukin-8 and vascular endothelial growth factor as well as their induced signaling pathways in ECs. In conclusion, these results show that L+E+P inhibits PCa progression and metastasis.


Assuntos
Ácido Elágico/farmacologia , Ácidos Linolênicos/farmacologia , Luteolina/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos , Quimiocina CXCL12/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Neovascularização Patológica/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores CXCR4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Am J Pathol ; 181(5): 1573-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23022210

RESUMO

Oncosomes are tumor-derived microvesicles that transmit signaling complexes between cell and tissue compartments. Herein, we show that amoeboid tumor cells export large (1- to 10-µm diameter) vesicles, derived from bulky cellular protrusions, that contain metalloproteinases, RNA, caveolin-1, and the GTPase ADP-ribosylation factor 6, and are biologically active toward tumor cells, endothelial cells, and fibroblasts. We describe methods by which large oncosomes can be selectively sorted by flow cytometry and analyzed independently of vesicles <1 µm. Structures resembling large oncosomes were identified in the circulation of different mouse models of prostate cancer, and their abundance correlated with tumor progression. Similar large vesicles were also identified in human tumor tissues, but they were not detected in the benign compartment. They were more abundant in metastases. Our results suggest that tumor microvesicles substantially larger than exosome-sized particles can be visualized and quantified in tissues and in the circulation, and isolated and characterized using clinically adaptable methods. These findings also suggest a mechanism by which migrating tumor cells condition the tumor microenvironment and distant sites, thereby potentiating advanced disease.


Assuntos
Micropartículas Derivadas de Células/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Fator 6 de Ribosilação do ADP , Animais , Caveolina 1/metabolismo , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/ultraestrutura , Citometria de Fluxo , Humanos , Masculino , Camundongos , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/ultraestrutura
10.
Proc Natl Acad Sci U S A ; 107(14): 6459-64, 2010 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-20308550

RESUMO

The phosphatase and tensin homolog (PTEN) is a tumor suppressor that is inactivated in many human cancers. PTEN loss has been associated with resistance to inhibitors of the epidermal growth factor receptor (EGFR), but the molecular basis of this resistance is unclear. It is believed that unopposed phosphatidylinositol-3-kinase (PI3K) activation through multiple receptor tyrosine kinases (RTKs) can relieve PTEN-deficient cancers from their "dependence" on EGFR or any other single RTK for survival. Here we report a distinct resistance mechanism whereby PTEN inactivation specifically raises EGFR activity by impairing the ligand-induced ubiquitylation and degradation of the activated receptor through destabilization of newly formed ubiquitin ligase Cbl complexes. PTEN-associated resistance to EGFR kinase inhibitors is phenocopied by expression of dominant negative Cbl and can be overcome by more complete EGFR kinase inhibition. PTEN inactivation does not confer resistance to inhibitors of the MET or PDGFRA kinase. Our study identifies a critical role for PTEN in EGFR signal termination and suggests that more potent EGFR inhibition should overcome resistance caused by PI3K pathway activation.


Assuntos
Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Animais , Apoptose , Linhagem Celular , Ativação Enzimática , Humanos , Camundongos , Camundongos Knockout , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Ubiquitinação
11.
Cancer Res Commun ; 2(6): 518-532, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911788

RESUMO

During the 9/11 attacks individuals were exposed to World Trade Center (WTC) dust which contained a complex mixture of carcinogens. Epidemiological studies have revealed the increased incidence of prostate and thyroid cancer in WTC survivors and responders. While reports have shown that WTC-dust associates with the increased prevalence of inflammatory related disorders, studies to date have not determined whether this exposure impacts cancer progression. In this study, we have used genetically engineered mouse (GEM) models with prostate specific deletion of the PTEN tumor suppressor to study the impact of WTC-dust exposure on deposition of dust particles, inflammation, and cancer progression. In normal C57/BL6 mice, dust exposure increased cellular expression of inflammatory genes with highest levels in the lung and peripheral blood. In normal and tumor bearing GEM mice, increased immune cell infiltration to the lungs was observed. Pathological evaluation of mice at different time points showed that WTC-dust exposure promoted PI3K-AKT activation, increased epithelial proliferation and acinar invasion in prostates with heterozygous and homozygous Pten loss. Using autochthonous and transplant GEM models of prostate cancer we demonstrated that dust exposure caused reduced survival as compared to control cohorts. Finally, we used imaging mass cytometry (IMC) to detect elevated immune cell infiltration and cellular expression of inflammatory markers in prostate tumors isolated from human WTC survivors. Collectively, our study shows that chronic inflammation, induced by WTC dust exposure, promotes more aggressive cancer in genetically predisposed prostates and potentially in patients.


Assuntos
Pneumopatias , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Poeira , Inflamação , Fosfatidilinositol 3-Quinases , Próstata , Neoplasias da Próstata/epidemiologia , PTEN Fosfo-Hidrolase/genética
12.
Cell Rep ; 40(4): 111123, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35905714

RESUMO

Treatment-emergent small cell neuroendocrine prostate cancer (t-SCNC) is associated with an epithelial lineage switch from an androgen receptor (AR)-positive to neuroendocrine (NE)-marker-positive status. Understanding the potential for reversibility of this aggressive disease state has been hampered by the paucity of models suitable for studying rate-limiting, transitional, or intermediate tumor cell subpopulations. We define a dual reporter model that measures acute transcriptional changes in response to castration or AR targeting agents. We identify steady-state transcriptional heterogeneity in AR and NE biomarkers, including intermediate subpopulations that are coordinately high for prostate-specific antigen (PSA) and neuron-specific enoclase (NSE) promoter activity. In the presence of castration or AR inhibitors, intermediate cells were necessary and sufficient for therapy-induced conversion of human PC cells to an NSE-high transcriptional status. Using hormone add-back studies, treatment-induced PSA-NSE transcriptional plasticity was reversible in PTEN-deficient PC cells but not in the presence of secondary genetic driver genes, including MYCN.


Assuntos
Carcinoma de Células Pequenas , Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Linhagem Celular Tumoral , Humanos , Masculino , Próstata/patologia , Antígeno Prostático Específico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/genética
13.
Mol Cancer Ther ; 21(11): 1729-1741, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36129800

RESUMO

SIGNIFICANCE: Most patients with bladder cancer do not respond to ICB targeting of the PD-L1 signaling axis. Our modeling applied a de novo resistance signature to show that tumor-infiltrating myeloid cells promote poor treatment response in a TGFß-dependent mechanism.


Assuntos
Antígeno B7-H1 , Neoplasias da Bexiga Urinária , Humanos , Antígeno B7-H1/genética , Fator de Crescimento Transformador beta , Células Mieloides , Transdução de Sinais , Microambiente Tumoral , Linfócitos do Interstício Tumoral
14.
Cancers (Basel) ; 13(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34771460

RESUMO

Acquired therapeutic resistance remains a major challenge in cancer management and associates with poor oncological outcomes in most solid tumor types. A major contributor is tumor heterogeneity (TH) which can be influenced by the stromal; immune and epithelial tumor compartments. We hypothesize that heterogeneity in tumor epithelial subpopulations-whether de novo or newly acquired-closely regulate the clinical course of bladder cancer. Changes in these subpopulations impact the tumor microenvironment including the extent of immune cell infiltration and response to immunotherapeutics. Mechanisms driving epithelial tumor heterogeneity (EpTH) can be broadly categorized as mutational and non-mutational. Mechanisms regulating lineage plasticity; acquired cellular mutations and changes in lineage-defined subpopulations regulate stress responses to clinical therapies. If tumor heterogeneity is a dynamic process; an increased understanding of how EpTH is regulated is critical in order for clinical therapies to be more sustained and durable. In this review and analysis, we assess the importance and regulatory mechanisms governing EpTH in bladder cancer and the impact on treatment response.

15.
Kidney360 ; 2(9): 1441-1454, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34651140

RESUMO

BACKGROUND: Proximal tubular (PT) cells are enriched in mitochondria and peroxisomes. Whereas mitochondrial fatty acid oxidation (FAO) plays an important role in kidney function by supporting the high-energy requirements of PT cells, the role of peroxisomal metabolism remains largely unknown. EHHADH, also known as L-bifunctional protein, catalyzes the second and third step of peroxisomal FAO. METHODS: We studied kidneys of WT and Ehhadh KO mice on a C57BL/6N background using histology, immunohistochemistry, immunofluorescence, immunoblot, RNA-sequencing, and metabolomics. To assess the role of androgens in the kidney phenotype of Ehhadh KO mice, mice underwent orchiectomy. RESULTS: We observed male-specific kidney hypertrophy and glomerular filtration rate reduction in adult Ehhadh KO mice. Transcriptome analysis unveiled a gene expression signature similar to PT injury in acute kidney injury mouse models. This was further illustrated by the presence of KIM-1 (kidney injury molecule-1), SOX-9, and Ki67-positive cells in the PT of male Ehhadh KO kidneys. Male Ehhadh KO kidneys had metabolite changes consistent with peroxisomal dysfunction as well as an elevation in glycosphingolipid levels. Orchiectomy of Ehhadh KO mice decreased the number of KIM-1 positive cells to WT levels. We revealed a pronounced sexual dimorphism in the expression of peroxisomal FAO proteins in mouse kidney, underlining a role of androgens in the kidney phenotype of Ehhadh KO mice. CONCLUSIONS: Our data highlight the importance of EHHADH and peroxisomal metabolism in male kidney physiology and reveal peroxisomal FAO as a sexual dimorphic metabolic pathway in mouse kidneys.


Assuntos
Rim , Peroxissomos , Animais , Hipertrofia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peroxissomos/metabolismo
16.
Elife ; 102021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34075878

RESUMO

High spliceosome activity is a dependency for cancer cells, making them more vulnerable to perturbation of the splicing machinery compared to normal cells. To identify splicing factors important for prostate cancer (PCa) fitness, we performed pooled shRNA screens in vitro and in vivo. Our screens identified heterogeneous nuclear ribonucleoprotein M (HNRNPM) as a regulator of PCa cell growth. RNA- and eCLIP-sequencing identified HNRNPM binding to transcripts of key homeostatic genes. HNRNPM binding to its targets prevents aberrant exon inclusion and backsplicing events. In both linear and circular mis-spliced transcripts, HNRNPM preferentially binds to GU-rich elements in long flanking proximal introns. Mimicry of HNRNPM-dependent linear-splicing events using splice-switching-antisense-oligonucleotides was sufficient to inhibit PCa cell growth. This suggests that PCa dependence on HNRNPM is likely a result of mis-splicing of key homeostatic coding and non-coding genes. Our results have further been confirmed in other solid tumors. Taken together, our data reveal a role for HNRNPM in supporting cancer cell fitness. Inhibition of HNRNPM activity is therefore a potential therapeutic strategy in suppressing growth of PCa and other solid tumors.


Assuntos
Adenocarcinoma/metabolismo , Proliferação de Células , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/metabolismo , Neoplasias da Próstata/metabolismo , Splicing de RNA , RNA Circular/biossíntese , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/genética , Humanos , Masculino , Camundongos SCID , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Circular/genética , Carga Tumoral , Células Tumorais Cultivadas
17.
J Biol Chem ; 284(44): 30159-66, 2009 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19740742

RESUMO

PTEN (phosphatase and tensin homolog deleted on chromosome 10) is well characterized for its role in antagonizing the phosphoinositide 3-kinase pathway. Previous studies using size-exclusion chromatography demonstrated PTEN recruitment into high molecular mass complexes and hypothesized that PTEN phosphorylation status and PDZ binding domain may be required for such complex formation. In this study, we set out to test the structural requirements for PTEN complex assembly and identify the component(s) of the PTEN complex(es). Our results demonstrated that the PTEN catalytic function and PDZ binding domain are not absolutely required for its complex formation. On the other hand, PTEN phosphorylation status has a significant impact on its complex assembly. Our results further demonstrate enrichment of the PTEN complex in nuclear lysates, suggesting a mechanism through which PTEN phosphorylation may regulate its complex assembly. These results prompted further characterization of other protein components within the PTEN complex(es). Using size-exclusion chromatography and two-dimensional difference gel electrophoresis followed by mass spectrometry analysis, we identified heterogeneous nuclear ribonucleoprotein C (hnRNP C) as a novel protein recruited to higher molecular mass fractions in the presence of PTEN. Further analysis indicates that endogenous hnRNP C and PTEN interact and co-localize within the nucleus, suggesting a potential role for PTEN, alongside hnRNP C, in RNA regulation.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo C/análise , PTEN Fosfo-Hidrolase/metabolismo , Transporte Ativo do Núcleo Celular , Linhagem Celular Tumoral , Cromatografia em Gel , Eletroforese em Gel Bidimensional , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Humanos , Masculino , Espectrometria de Massas , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/análise , Proteínas Nucleares/metabolismo , Fosforilação
18.
Prostate Cancer Prostatic Dis ; 23(4): 718-723, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32661432

RESUMO

BACKGROUND: The loss of PTEN function presents in up to 50% of late-stage prostate cancers, and is therefore a potential target for therapeutics. PTEN-deficient cells depend on de novo pyrimidine synthesis, a feature that can present a vulnerability. METHODS: We utilized in vitro growth assays and in vivo xenograft models to test the effect of de novo pyrimidine synthesis inhibition on prostate cell lines. RESULTS: Here, we demonstrate that PTEN-deficient prostate cancer cell lines are susceptible to inhibition of de novo pyrimidine synthesis by leflunomide. Tumor growth inhibition was observed in vitro and in vivo following leflunomide treatment, and is likely due to an overwhelming accumulation of DNA damage. CONCLUSIONS: Our work highlights that synthetic lethality arises upon the combination of PTEN loss and leflunomide treatment in prostate cancer, and may present a therapeutic opportunity for this patient population.


Assuntos
Leflunomida/toxicidade , PTEN Fosfo-Hidrolase/deficiência , Neoplasias da Próstata/patologia , Pirimidinas/metabolismo , Mutações Sintéticas Letais , Animais , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Imunossupressores/toxicidade , Masculino , Camundongos , Camundongos Nus , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Nat Commun ; 11(1): 2540, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439865

RESUMO

Tumor heterogeneity is common in cancer, however recent studies have applied single gene expression signatures to classify bladder cancers into distinct subtypes. Such stratification assumes that a predominant transcriptomic signature is sufficient to predict progression kinetics, patient survival and treatment response. We hypothesize that such static classification ignores intra-tumoral heterogeneity and the potential for cellular plasticity occurring during disease development. We have conducted single cell transcriptome analyses of mouse and human model systems of bladder cancer and show that tumor cells with multiple lineage subtypes not only cluster closely together at the transcriptional level but can maintain concomitant gene expression of at least one mRNA subtype. Functional studies reveal that tumor initiation and cellular plasticity can initiate from multiple lineage subtypes. Collectively, these data suggest that lineage plasticity may contribute to innate tumor heterogeneity, which in turn carry clinical implications regarding the classification and treatment of bladder cancer.


Assuntos
Linhagem da Célula/genética , Plasticidade Celular/genética , Neoplasias da Bexiga Urinária/patologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Transformação Celular Neoplásica/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Integrina alfa6/genética , Integrina alfa6/metabolismo , Queratina-5/genética , Queratina-5/metabolismo , Camundongos , Fenótipo , Análise de Célula Única , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
20.
Endocr Rev ; 26(7): 898-915, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16126938

RESUMO

The cross-regulation of Wnt/beta-catenin/Tcf ligands, kinases, and transcription factors with members of the nuclear receptor (NR) family has emerged as a clinically and developmentally important area of endocrine cell biology. Interactions between these signaling pathways result in a diverse array of cellular effects including altered cellular adhesion, tissue morphogenesis, and oncogenesis. Analyses of NR interactions with canonical Wnt signaling reveal two broad themes: Wnt/beta-catenin modulation of NRs (theme I), and ligand-dependent NR inhibition of the Wnt/beta-catenin/Tcf cascade (theme II). Beta-catenin, a promiscuous Wnt signaling member, has been studied intensively in relation to the androgen receptor (AR). Beta-catenin acts as a coactivator of AR transcription and is also involved in co-trafficking, increasing cell proliferation, and prostate pathogenesis. T cell factor, a transcriptional mediator of beta-catenin and AR, engages in a dynamic reciprocity of nuclear beta-catenin, p300/CREB binding protein, and transcriptional initiation factor 2/GC receptor-interaction protein, thereby facilitating hormone-dependent coactivation and transrepression. Beta-catenin responds in an equally dynamic manner with other NRs, including the retinoic acid (RA) receptor (RAR), vitamin D receptor (VDR), glucocorticoid receptor (GR), progesterone receptor, thyroid receptor (TR), estrogen receptor (ER), and peroxisome proliferator-activated receptor (PPAR). The NR ligands, vitamin D(3), trans/cis RA, glucocorticoids, and thiazolidines, induce dramatic changes in the physiology of cells harboring high Wnt/beta-catenin/Tcf activity. Wnt signaling regulates, directly or indirectly, developmental processes such as ductal branching and adipogenesis, two processes dependent on NR function. Beta-catenin has been intensively studied in colorectal cancer; however, it is now evident that beta-catenin may be important in cancers of the breast, prostate, and thyroid. This review will focus on the cross-regulation of AR and Wnt/beta-catenin/Tcf but will also consider the dynamic manner in which RAR/RXR, GR, TR, VDR, ER, and PPAR modulate canonical Wnt signaling. Although many commonalities exist by which NRs interact with the Wnt/beta-catenin signaling pathway, striking cell line and tissue-specific differences require deciphering and application to endocrine pathology.


Assuntos
Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição TCF/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Humanos
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