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1.
J Biol Chem ; 299(8): 104973, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37380074

RESUMO

Prostate cancer is initially regulated by the androgen receptor (AR), a ligand-activated, transcription factor, and is in a hormone-dependent state (hormone-sensitive prostate cancer (HSPC)), but eventually becomes androgen-refractory (castration-resistant prostate cancer (CRPC)) because of mechanisms that bypass the AR, including by activation of ErbB3, a member of the epidermal growth factor receptor family. ErbB3 is synthesized in the cytoplasm and transported to the plasma membrane for ligand binding and dimerization, where it regulates downstream signaling, but nuclear forms are reported. Here, we demonstrate in prostatectomy samples that ErbB3 nuclear localization is observed in malignant, but not benign prostate, and that cytoplasmic (but not nuclear) ErbB3 correlated positively with AR expression but negatively with AR transcriptional activity. In support of the latter, androgen depletion upregulated cytoplasmic, but not nuclear ErbB3, while in vivo studies showed that castration suppressed ErbB3 nuclear localization in HSPC, but not CRPC tumors. In vitro treatment with the ErbB3 ligand heregulin-1ß (HRG) induced ErbB3 nuclear localization, which was androgen-regulated in HSPC but not in CRPC. In turn, HRG upregulated AR transcriptional activity in CRPC but not in HSPC cells. Positive correlation between ErbB3 and AR expression was demonstrated in AR-null PC-3 cells where stable transfection of AR restored HRG-induced ErbB3 nuclear transport, while AR knockdown in LNCaP reduced cytoplasmic ErbB3. Mutations of ErbB3's kinase domain did not affect its localization but was responsible for cell viability in CRPC cells. Taken together, we conclude that AR expression regulated ErbB3 expression, its transcriptional activity suppressed ErbB3 nuclear translocation, and HRG binding to ErbB3 promoted it.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Receptores Androgênicos , Humanos , Masculino , Androgênios/metabolismo , Linhagem Celular Tumoral , Ligantes , Neuregulina-1/genética , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Proteína Tirosina Quinases , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
2.
Int J Mol Sci ; 25(16)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39201315

RESUMO

In prostate cancer (PCa), androgens upregulate tumorigenesis, whereas in benign tissue, the revival of androgen receptor (AR) signaling suppresses aggressive behaviors, suggesting therapeutic potential. Dogs, natural PCa models, often lack AR in PCa. We restored AR in dog PCa to investigate resultant characteristics. Three AR-null canine PCa lines (1508, Leo, 1258) were transfected with canine wild-type AR and treated with dihydrotestosterone (DHT). In 1508, AR restoration decreased clonogenicity (p = 0.03), viability (p = 0.004), migration (p = 0.03), invasion (p = 0.01), and increased expression of the tumor suppressor NKX3.1, an AR transcriptional target (p = 0.001). In Leo, AR decreased clonogenicity (p = 0.04) and the expression of another AR transcriptional target FOLH1 (p < 0.001) and increased the expression of NKX3.1 (p = 0.01). In 1258, AR increased migration (p = 0.006) and invasion (p = 0.03). Epithelial-mesenchymal transition (EMT) marker (Vimentin, N-cadherin, SNAIL1) expression increased with AR restoration in Leo and 1258 but not 1508; siRNA vimentin knockdown abrogated AR-induced 1258 migration only. Overall, 1508 showed AR-mediated tumor suppression; AR affected proliferation in Leo but not migration or invasion; and EMT and AR regulated migration and invasion in 1258 but not proliferation. This study highlights the heterogeneous nature of PCa in dogs and cell line-specific effects of AR abrogation on aggressive behaviors.


Assuntos
Movimento Celular , Transição Epitelial-Mesenquimal , Neoplasias da Próstata , Receptores Androgênicos , Transdução de Sinais , Animais , Cães , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Masculino , Linhagem Celular Tumoral , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Invasividade Neoplásica , Proliferação de Células
3.
Int J Mol Sci ; 24(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37511154

RESUMO

Multiple risk factors have been associated with bladder cancer. This review focuses on pesticide exposure, as it is not currently known whether agricultural products have a direct or indirect effect on bladder cancer, despite recent reports demonstrating a strong correlation. While it is known that pesticide exposure is associated with an increased risk of bladder cancer in humans and dogs, the mechanism(s) by which specific pesticides cause bladder cancer initiation or progression is unknown. In this narrative review, we discuss what is currently known about pesticide exposure and the link to bladder cancer. This review highlights multiple pathways modulated by pesticide exposure with direct links to bladder cancer oncogenesis/metastasis (MMP-2, TGF-ß, STAT3) and chemoresistance (drug efflux, DNA repair, and apoptosis resistance) and potential therapeutic tactics to counter these pesticide-induced affects.


Assuntos
Antineoplásicos , Praguicidas , Neoplasias da Bexiga Urinária , Humanos , Animais , Cães , Praguicidas/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Fatores de Risco , Antineoplásicos/efeitos adversos
4.
Br J Cancer ; 121(3): 237-248, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209328

RESUMO

BACKGROUND: Despite overexpression of the ErbB (EGFR/HER2/ErbB3/ErbB4) family in castration-resistant prostate cancer (CRPC), some inhibitors of this family, including the dual EGFR/HER2 inhibitor lapatinib, failed in Phase II clinical trials. Hence, we investigated mechanisms of lapatinib resistance to determine whether alternate ErbB inhibitors can succeed. METHODS: The CWR22 human tumour xenograft and its CRPC subline 22Rv1 and sera from lapatinib-treated CRPC patients from a previously reported Phase II trial were used to study lapatinib resistance. Mechanistic studies were conducted in LNCaP, C4-2 and 22Rv1 cell lines. RESULTS: Lapatinib increased intratumoral HER2 protein, which encouraged resistance to this treatment in mouse models. Sera from CRPC patients following lapatinib treatment demonstrated increased HER2 levels. Investigation of the mechanism of lapatinib-induced HER2 increase revealed that lapatinib promotes HER2 protein stability, leading to membrane localisation, EGFR/HER2 heterodimerisation and signalling, elevating cell viability. Knockdown of HER2 and ErbB3, but not EGFR, sensitised CRPC cells to lapatinib. At equimolar concentrations, the recently FDA-approved pan-ErbB inhibitor dacomitinib decreased HER2 protein stability, prevented ErbB membrane localisation (despite continued membrane integrity) and EGFR/HER2 heterodimerisation, thereby decreasing downstream signalling and increasing apoptosis. CONCLUSIONS: Targeting the EGFR axis using the irreversible pan-ErbB inhibitor dacomitinib is a viable therapeutic option for CRPC.


Assuntos
Lapatinib/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Quinazolinonas/uso terapêutico , Receptor ErbB-2/biossíntese , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Receptores ErbB/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias de Próstata Resistentes à Castração/metabolismo , Multimerização Proteica , Receptor ErbB-2/sangue , Receptor ErbB-2/química
5.
Int J Mol Sci ; 20(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875757

RESUMO

Several studies by our group and others have determined that expression levels of Bcl-2 and/or Bcl-xL, pro-survival molecules which are associated with chemoresistance, are elevated in patients with muscle invasive bladder cancer (MI-BC). The goal of this study was to determine whether combining Obatoclax, a BH3 mimetic which inhibits pro-survival Bcl-2 family members, can improve responses to cisplatin chemotherapy, the standard of care treatment for MI-BC. Three MI-BC cell lines (T24, TCCSuP, 5637) were treated with Obatoclax alone or in combination with cisplatin and/or pre-miR-34a, a molecule which we have previously shown to inhibit MI-BC cell proliferation via decreasing Cdk6 expression. Proliferation, clonogenic, and apoptosis assays confirmed that Obatoclax can decrease cell proliferation and promote apoptosis in a dose-dependent manner. Combination treatment experiments identified Obatoclax + cisplatin as the most effective treatment. Immunoprecipitation and Western analyses indicate that, in addition to being able to inhibit Bcl-2 and Bcl-xL, Obatoclax can also decrease cyclin D1 and Cdk4/6 expression levels. This has not previously been reported. The combined data demonstrate that Obatoclax can inhibit cell proliferation, promote apoptosis, and significantly enhance the effectiveness of cisplatin in MI-BC cells via mechanisms that likely involve the inhibition of both pro-survival molecules and cell cycle regulators.


Assuntos
Cisplatino/farmacologia , Pirróis/farmacologia , Neoplasias da Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Bexiga Urinária/efeitos dos fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Proteína bcl-X/metabolismo
6.
Int J Mol Sci ; 20(20)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600961

RESUMO

Bladder cancer is among the top ten most common cancers, with about ~380,000 new cases and ~150,000 deaths per year worldwide. Tumor relapse following chemotherapy treatment has long been a significant challenge towards completely curing cancer. We have utilized a patient-derived bladder cancer xenograft (PDX) platform to characterize molecular mechanisms that contribute to relapse following drug treatment in advanced bladder cancer. Transcriptomic profiling of bladder cancer xenograft tumors by RNA-sequencing analysis, before and after relapse, following a 21-day cisplatin/gemcitabine drug treatment regimen identified methionine adenosyltransferase 1a (MAT1A) as one of the significantly upregulated genes following drug treatment. Survey of patient tumor sections confirmed elevated levels of MAT1A in individuals who received chemotherapy. Overexpression of MAT1A in 5637 bladder cancer cells increased tolerance to gemcitabine and stalled cell proliferation rates, suggesting MAT1A upregulation as a potential mechanism by which bladder cancer cells persist in a quiescent state to evade chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Metionina Adenosiltransferase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metionina Adenosiltransferase/metabolismo , Camundongos , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Am J Physiol Regul Integr Comp Physiol ; 314(4): R574-R583, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29212811

RESUMO

Increased ß-adrenergic receptor (ß-AR)-mediated activation of adenylyl cyclase (AC) in rat liver during aging has been linked to age-related increases in hepatic glucose output and hepatosteatosis. In this study, we investigated the expression of ß-ARs, individual receptor subtypes, and G protein-coupled receptor (GPCR) regulatory proteins in livers from aging rats. Radioligand-binding studies demonstrated that ß-AR density increased by greater than threefold in hepatocyte membranes from senescent (24-mo-old) compared with young adult (7-mo-old) rats and that this phenomenon was blocked by food restriction, which is known to retard aging processes in rodents. Competition-binding studies revealed a mixed population of ß1- and ß2-AR subtypes in liver membranes over the adult life span, with a trend for greater ß2-AR density with age. Expression of both ß-AR subtype mRNAs in rat liver increased with age, whereas ß2- but not ß1-AR protein levels declined in livers of old animals. Immunoreactive ß2- but not ß1-ARs were preferentially distributed in pericentral hepatic regions. Levels of GRK2/3 and ß-arrestin 2 proteins, which are involved in downregulation of agonist-activated GPCRs, including ß-ARs, increased during aging. Insofar as sympathetic tone increases with age, our findings suggest that, despite enhanced agonist-mediated downregulation of hepatic ß-ARs preferentially affecting the ß2-AR subtype, increased generation of both receptor subtypes during aging augments the pool of plasma membrane-bound ß-ARs coupled to AC in hepatocytes. This study thus identifies one or both ß-AR subtypes as possible therapeutic targets involved in aberrant hepatic processes of glucose and lipid metabolism during aging.


Assuntos
Envelhecimento/metabolismo , Membrana Celular/metabolismo , Metabolismo Energético , Hepatócitos/metabolismo , Fígado/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Fatores Etários , Envelhecimento/genética , Animais , Restrição Calórica , Metabolismo Energético/genética , Quinase 2 de Receptor Acoplado a Proteína G/genética , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Quinase 3 de Receptor Acoplado a Proteína G/genética , Quinase 3 de Receptor Acoplado a Proteína G/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Ligantes , Metabolismo dos Lipídeos , Fígado/fisiopatologia , Masculino , Ratos Endogâmicos F344 , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , beta-Arrestina 2/genética , beta-Arrestina 2/metabolismo
8.
Cancer ; 122(12): 1897-904, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27019001

RESUMO

BACKGROUND: The mammalian target of rapamycin (mTOR) pathway is up-regulated in castration-resistant prostate cancer (CRPC). Nevertheless, inhibition of mTOR is ineffective in inducing apoptosis in prostate cancer cells, likely because of the compensatory up-regulation of the androgen receptor (AR) pathway. METHODS: Patients who were eligible for this study had to have progressive CRPC with serum testosterone levels <50 ng/dL. No prior bicalutamide (except to prevent flare) or everolimus was allowed. Treatment included oral bicalutamide 50 mg and oral everolimus 10 mg, both once daily, with a cycle defined as 4 weeks. The primary endpoint was the prostate-specific antigen (PSA) response (≥30% reduction) from baseline. A sample size of 23 patients would have power of 0.8 and an α error of .05 (1-sided) if the combination had a PSA response rate of 50% versus a historic rate of 25% with bicalutamide alone. RESULTS: Twenty-four patients were enrolled. The mean age was 71.1 years (range, 53.0-87.0 years), the mean PSA level at study entry was 43.4 ng/dL (range, 2.5-556.9 ng/dL), and the mean length of treatment was 8 cycles (range, 1.0-23.0 cycles). Of 24 patients, 18 had a PSA response (75%; 95% confidence interval [CI], 0.53-0.90), whereas 15 (62.5%; 95% CI, 0.41-0.81) had a PSA decrease ≥50%. The median overall survival was 28 months (95% CI, 14.1-42.7 months). Fourteen patients (54%; 95% CI, 0.37-0.78) developed grade 3 (13 patients) or grade 4 (1 patient with sepsis) adverse events that were attributable to treatment. CONCLUSIONS: The combination of bicalutamide and everolimus has encouraging efficacy in men with bicalutamide-naive CRPC, thus warranting further investigation. A substantial number of patients experienced everolimus-related toxicity. Cancer 2016;122:1897-904. © 2016 American Cancer Society.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/administração & dosagem , Anilidas/administração & dosagem , Everolimo/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Receptores Androgênicos/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Compostos de Tosil/administração & dosagem
9.
Mol Carcinog ; 55(5): 757-67, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25865490

RESUMO

Urothelial cell carcinoma of the bladder (UCCB) is the most common form of bladder cancer and it is estimated that ~15,000 people in the United States succumbed to this disease in 2013. Bladder cancer treatment options are limited and research to understand the molecular mechanisms of this disease is needed to design novel therapeutic strategies. Recent studies have shown that microRNAs play pivotal roles in the progression of cancer. miR-148a has been shown to serve as a tumor suppressor in cancers of the prostate, colon, and liver, but its role in bladder cancer has never been elucidated. Here we show that miR-148a is down-regulated in UCCB cell lines. We demonstrate that overexpression of miR-148a leads to reduced cell viability through an increase in apoptosis rather than an inhibition of proliferation. We additionally show that miR-148a exerts this effect partially by attenuating expression of DNA methyltransferase 1 (DNMT1). Finally, our studies demonstrate that treating cells with both miR-148a and either cisplatin or doxorubicin is either additive or synergistic in causing apoptosis. These data taken together suggest that miR-148a is a tumor suppressor in UCCB and could potentially serve as a novel therapeutic for this malignancy.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Urotélio/patologia , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Cisplatino/farmacologia , DNA (Citosina-5-)-Metiltransferase 1 , Regulação para Baixo , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias da Bexiga Urinária/patologia
10.
Carcinogenesis ; 36 Suppl 1: S89-110, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106145

RESUMO

Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically, the up-regulation of pro-survival factors, including oncogenic factors and antiapoptotic signaling pathways, and the down-regulation of pro-apoptotic factors, including tumor suppressive factors, confers resistance to cell death in tumor cells, which supports the emergence of a fully immortalized cellular phenotype. This review considers the potential relevance of ubiquitous environmental chemical exposures that have been shown to disrupt key pathways and mechanisms associated with this sort of dysfunction. Specifically, bisphenol A, chlorothalonil, dibutyl phthalate, dichlorvos, lindane, linuron, methoxychlor and oxyfluorfen are discussed as prototypical chemical disruptors; as their effects relate to resistance to cell death, as constituents within environmental mixtures and as potential contributors to environmental carcinogenesis.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos Ambientais/efeitos adversos , Morte Celular/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Animais , Homeostase/efeitos dos fármacos , Humanos
11.
J Urol ; 193(1): 19-29, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25158272

RESUMO

PURPOSE: Conventional platinum based chemotherapy for advanced urothelial carcinoma is plagued by common resistance to this regimen. Several studies implicate the EGFR family of RTKs in urothelial carcinoma progression and chemoresistance. Many groups have investigated the effects of inhibitors of this family in patients with urothelial carcinoma. This review focuses on the underlying molecular pathways that lead to urothelial carcinoma resistance to EGFR family inhibitors. MATERIALS AND METHODS: We performed a PubMed® search for peer reviewed literature on bladder cancer development, EGFR family expression, clinical trials of EGFR family inhibitors and molecular bypass pathways. Research articles deemed to be relevant were examined and a summary of original data was created. Meta-analysis of expression profiles was also performed for each EGFR family member based on data sets accessible via Oncomine®. RESULTS: Many clinical trials using inhibitors of EGFR family RTKs have been done or are under way. Those that have concluded with results published to date do not show an added benefit over standard of care chemotherapy in an adjuvant or second line setting. However, a neoadjuvant study using erlotinib before radical cystectomy demonstrated promising results. CONCLUSIONS: Clinical and preclinical studies show that for reasons not currently clear prior treatment with chemotherapeutic agents rendered patients with urothelial carcinoma with muscle invasive bladder cancer resistant to EGFR family inhibitors as well. However, EGFR family inhibitors may be of use in patients with no prior chemotherapy in whom EGFR or ERBB2 is over expressed.


Assuntos
Receptores ErbB/antagonistas & inibidores , Neoplasias da Bexiga Urinária/tratamento farmacológico , Humanos , Músculo Liso , Invasividade Neoplásica , Transdução de Sinais , Neoplasias da Bexiga Urinária/patologia
12.
Animals (Basel) ; 14(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38396556

RESUMO

Clinicopathologic data in dogs with prostate cancer (PCa) may aid in the differentiation between tumor types and subsequent treatment decisions; however, these data are often unreported. Demographic, clinicopathologic, cytologic, histologic and survival data from dogs with primary prostatic adenocarcinoma (PRAD) (n = 56) and primary prostatic transitional cell carcinoma (P-TCC) (n = 74) were acquired from a tertiary veterinary teaching hospital from 1992 to 2022. Red blood cell distribution width (RDW) to albumin ratio (RAR) was evaluated for diagnostic utility in differentiating between PRAD and P-TCC. Sections from PRAD tumors (n = 50) were stained for androgen receptor (AR) expression, and laboratory data were compared between AR positive (AR+) and AR negative (AR-) groups. RDW was increased in PRAD, while albumin was decreased (p < 0.05). P-TCC was associated with Melamed-Wolinska bodies (MWB) and necrosis on cytology (p < 0.05). RAR had acceptable diagnostic utility in the differentiation of PCa tumors (AUC = 0.7; p < 0.05). Survival rates and metastases were equivocal. AR+ and AR- PRAD tumors did not differ in clinicopathologic data or survival (p > 0.05). In conclusion, hypoalbuminemia was significantly associated with PRAD and decreased survival, while MWB and necrosis were significantly associated with P-TCC on cytology. These clinicopathologic data may help clinicians differentiate between these tumors ante mortem to guide appropriate treatment and intervention.

13.
Cell Death Dis ; 15(8): 617, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39183332

RESUMO

Resistance to the current Androgen Receptor Signaling Inhibitor (ARSI) therapies has led to higher incidences of therapy-induced neuroendocrine-like prostate cancer (t-NEPC). This highly aggressive subtype with predominant small-cell-like characteristics is resistant to taxane chemotherapies and has a dismal overall survival. t-NEPCs are mostly treated with platinum-based drugs with a combination of etoposide or taxane and have less selectivity and high systemic toxicity, which often limit their clinical potential. During t-NEPC transformation, adenocarcinomas lose their luminal features and adopt neuro-basal characteristics. Whether the adaptive neuronal characteristics of t-NEPC are responsible for such taxane resistance remains unknown. Pathway analysis from patient gene-expression databases indicates that t-NEPC upregulates various neuronal pathways associated with enhanced cellular networks. To identify transcription factor(s) (TF) that could be important for promoting the gene expression for neuronal characters in t-NEPC, we performed ATAC-Seq, acetylated-histone ChIP-seq, and RNA-seq in our NE-like cell line models and analyzed the promoters of transcriptionally active and significantly enriched neuroendocrine-like (NE-like) cancer-specific genes. Our results indicate that Pax5 could be an important transcription factor for neuronal gene expression and specific to t-NEPC. Pathway analysis revealed that Pax5 expression is involved in axonal guidance, neurotransmitter regulation, and neuronal adhesion, which are critical for strong cellular communications. Further results suggest that depletion of Pax5 disrupts neurite-mediated cellular communication in NE-like cells and reduces surface growth factor receptor activation, thereby, sensitizing them to docetaxel therapies. Moreover, t-NEPC-specific hydroxymethylation of Pax5 promoter CpG islands favors Pbx1 binding to induce Pax5 expression. Based on our study, we concluded that continuous exposure to ARSI therapies leads to epigenetic modifications and Pax5 activation in t-NEPC, which promotes the expression of genes necessary to adopt taxane-resistant NE-like cancer. Thus, targeting the Pax5 axis can be beneficial for reverting their taxane sensitivity.


Assuntos
Docetaxel , Resistencia a Medicamentos Antineoplásicos , Fator de Transcrição PAX5 , Neoplasias da Próstata , Humanos , Masculino , Docetaxel/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Fator de Transcrição PAX5/metabolismo , Fator de Transcrição PAX5/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antineoplásicos/farmacologia , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/genética , Regiões Promotoras Genéticas/genética , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética
14.
Biomedicines ; 11(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37626712

RESUMO

Multiple studies have demonstrated the importance of androgen receptor (AR) splice variants (SVs) in the progression of prostate cancer to the castration-resistant phenotype and their utility as a diagnostic. However, studies on AR expression in non-prostatic malignancies uncovered that AR-SVs are expressed in glioblastoma, breast, salivary, bladder, kidney, and liver cancers, where they have diverse roles in tumorigenesis. AR-SVs also have roles in non-cancer pathologies. In granulosa cells from women with polycystic ovarian syndrome, unique AR-SVs lead to an increase in androgen production. In patients with nonobstructive azoospermia, testicular Sertoli cells exhibit differential expression of AR-SVs, which is associated with impaired spermatogenesis. Moreover, AR-SVs have been identified in normal cells, including blood mononuclear cells, neuronal lipid rafts, and the placenta. The detection and characterization of AR-SVs in mammalian and non-mammalian species argue that AR-SV expression is evolutionarily conserved and that AR-SV-dependent signaling is a fundamental regulatory feature in multiple cellular contexts. These discoveries argue that alternative splicing of the AR transcript is a commonly used mechanism that leads to an expansion in the repertoire of signaling molecules needed in certain tissues. Various malignancies appropriate this mechanism of alternative AR splicing to acquire a proliferative and survival advantage.

15.
Biomedicines ; 11(4)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37189720

RESUMO

Dogs are one of few species that naturally develop prostate cancer (PCa), which clinically resembles aggressive, advanced PCa in humans. Moreover, PCa-tumor samples from dogs are often androgen receptor (AR)-negative and may enrich our understanding of AR-indifferent PCa in humans, a highly lethal subset of PCa for which few treatment modalities are available This narrative review discusses the molecular similarities between dog PCa and specific human-PCa variants, underscoring the possibilities of using the dog as a novel pre-clinical animal model for human PCa, resulting in new therapies and diagnostics that may benefit both species.

16.
Sci Rep ; 13(1): 1762, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36720985

RESUMO

The observed sex disparity in bladder cancer (BlCa) argues that androgen receptor (AR) signaling has a role in these malignancies. BlCas express full-length AR (FL-AR), constitutively active AR splice variants, including AR-v19, or both, and their depletion limits BlCa viability. However, the mechanistic basis of AR-dependence is unknown. Here, we depleted FL-AR, AR-v19, or all AR forms (T-AR), and performed RNA-seq studies to uncover that different AR forms govern distinct but partially overlapping transcriptional programs. Overlapping alterations include a decrease in mTOR and an increase of hypoxia regulated transcripts accompanied by a decline in oxygen consumption rate (OCR). Queries of BlCa databases revealed a significant negative correlation between AR expression and multiple hypoxia-associated transcripts arguing that this regulatory mechanism is a feature of high-grade malignancies. Our analysis of a 1600-compound library identified niclosamide as a strong ATPase inhibitor that reduces OCR in BlCa cells, decreased cell viability and induced apoptosis in a dose and time dependent manner. These results suggest that BlCa cells hijack AR signaling to enhance metabolic activity, promoting cell proliferation and survival; hence targeting this AR downstream vulnerability presents an attractive strategy to limit BlCa.


Assuntos
Receptores Androgênicos , Neoplasias da Bexiga Urinária , Humanos , Receptores Androgênicos/genética , Bexiga Urinária , Neoplasias da Bexiga Urinária/genética , Células Epiteliais , Hipóxia
17.
Endocr Relat Cancer ; 30(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37226936

RESUMO

Prostate cancer (PCa) is an increasingly prevalent health problem in the developed world. Effective treatment options exist for localized PCa, but metastatic PCa has fewer treatment options and shorter patient survival. PCa and bone health are strongly entwined, as PCa commonly metastasizes to the skeleton. Since androgen receptor signaling drives PCa growth, androgen-deprivation therapy whose sequelae reduce bone strength constitutes the foundation of advanced PCa treatment. The homeostatic process of bone remodeling - produced by concerted actions of bone-building osteoblasts, bone-resorbing osteoclasts, and regulatory osteocytes - may also be subverted by PCa to promote metastatic growth. Mechanisms driving skeletal development and homeostasis, such as regional hypoxia or matrix-embedded growth factors, may be subjugated by bone metastatic PCa. In this way, the biology that sustains bone is integrated into adaptive mechanisms for the growth and survival of PCa in bone. Skeletally metastatic PCa is difficult to investigate due to the entwined nature of bone biology and cancer biology. Herein, we survey PCa from origin, presentation, and clinical treatment to bone composition and structure and molecular mediators of PCa metastasis to bone. Our intent is to quickly yet effectively reduce barriers to team science across multiple disciplines that focuses on PCa and metastatic bone disease. We also introduce concepts of tissue engineering as a novel perspective to model, capture, and study complex cancer-microenvironment interactions.


Assuntos
Neoplasias Ósseas , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Neoplasias Ósseas/secundário , Antagonistas de Androgênios/uso terapêutico , Osso e Ossos/metabolismo , Resultado do Tratamento , Microambiente Tumoral
18.
Sci Rep ; 13(1): 9617, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316561

RESUMO

Cisplatin-based combination chemotherapy is the foundation for treatment of advanced bladder cancer (BlCa), but many patients develop chemoresistance mediated by increased Akt and ERK phosphorylation. However, the mechanism by which cisplatin induces this increase has not been elucidated. Among six patient-derived xenograft (PDX) models of BlCa, we observed that the cisplatin-resistant BL0269 express high epidermal growth factor receptor, ErbB2/HER2 and ErbB3/HER3. Cisplatin treatment transiently increased phospho-ErbB3 (Y1328), phospho-ERK (T202/Y204) and phospho-Akt (S473), and analysis of radical cystectomy tissues from patients with BlCa showed correlation between ErbB3 and ERK phosphorylation, likely due to the activation of ERK via the ErbB3 pathway. In vitro analysis revealed a role for the ErbB3 ligand heregulin1-ß1 (HRG1/NRG1), which is higher in chemoresistant lines compared to cisplatin-sensitive cells. Additionally, cisplatin treatment, both in PDX and cell models, increased HRG1 levels. The monoclonal antibody seribantumab, that obstructs ErbB3 ligand-binding, suppressed HRG1-induced ErbB3, Akt and ERK phosphorylation. Seribantumab also prevented tumor growth in both the chemosensitive BL0440 and chemoresistant BL0269 models. Our data demonstrate that cisplatin-associated increases in Akt and ERK phosphorylation is mediated by an elevation in HRG1, suggesting that inhibition of ErbB3 phosphorylation may be a useful therapeutic strategy in BlCa with high phospho-ErbB3 and HRG1 levels.


Assuntos
Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Animais , Cisplatino/farmacologia , Anticorpos Monoclonais , Neuregulina-1 , Ligantes , Proteínas Proto-Oncogênicas c-akt , Neoplasias da Bexiga Urinária/tratamento farmacológico , Modelos Animais de Doenças
19.
Metabolites ; 12(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323643

RESUMO

Urothelial carcinoma (UC), the most common urologic cancer in dogs, is often diagnosed late because the clinical signs are shared by other non-malignant lower urinary tract disorders (LUTD). The urine-based BRAFV595E test for UC is highly effective only in certain breeds; hence additional non-invasive biomarkers of UC are needed. Here, urine from dogs with UC (n = 27), urolithiasis (n = 8), or urolithiasis with urinary tract infection (UTI) (n = 8) were subjected to untargeted metabolomics analyses, using GC-TOF-MS for primary metabolites, QTOF-MS for complex lipids, and HILIC-QTOF MS for secondary and charged metabolites. After adjusting for age and sex, we identified 1123 known metabolites that were differentially expressed between UC and LUTD. Twenty-seven metabolites were significant (1.5 ≤ log2FC ≤ −1.5, adjusted p-value < 0.05); however, 10 of these could be attributed to treatment-related changes. Of the remaining 17, 6 (hippuric acid, N-Acetylphenylalanine, sarcosine, octanoylcarnitine, N-alpha-methylhistamine, glycerol-3-galactoside) discriminated between UC and LUTD (area under the ROC curve > 0.85). Of the 6 metabolites, only hippuric acid and N-alpha-methylhistamine were discriminatory in both male (n = 20) and female (n = 23) dogs, while sarcosine was an effective discriminator in several breeds, but only in females. Further investigation of these metabolites is warranted for potential use as non-invasive diagnostic biomarkers of dogs with UC that present with LUTD-related clinical signs.

20.
Ann Transl Med ; 10(13): 754, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35957716

RESUMO

Background and Objective: Multiple studies have demonstrated the medical potency of plant extracts and specific phytochemicals as therapeutics for prostate cancer (PCa) patients. Of note, the Neem plant known for its role as an antibiotic and anti-inflammatory is underexplored with an untapped potential for further development. This review focuses on extracts and phytochemicals derived from the Neem tree (Latin name; Azadirachta indica), commonly used throughout Southeast Asia for the prevention and treatment of a wide array of diseases including cancer. To date, there are more than 130 biologically active compounds that have been isolated from the Neem tree including azadirachtin, nimbolinin, nimbin, nimbidin, nimbidol, which have demonstrated a wide range of biological activities including anti-microbial, anti-fertility, anti-inflammatory, anti-arthritic, hepatoprotective, anti-diabetic, anti-ulcer, and anti-cancer effects. Very few scientific reports focus on the benefits of Neem in PCa, even though this herb has been used to prevent the disease and its progression for years in complementary and alternative medicine. Methods: We used the search engines like PubMed, InCommon and Google using the key words: "Neem", "Cancer", "Prostate Cancer" and related words to find the information and data within the time frame from 1980-2022 for our article study. Key Content and Findings: Here, we provide an overview of Neem extracts and phytochemical derivatives with a focus on their known potential and ability to inhibit specific cellular signaling pathways and processes which drive PCa incidence and progression. Conclusions: The information presented here indicate that Neem and its derivatives have a therapeutic potential for the treatment of PCa when used as a single agent or in combination with conventional chemotherapeutics.

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