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1.
Int. braz. j. urol ; 45(3): 459-467, May-June 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1012312

RESUMO

ABSTRACT Purpose: 68Ga-PSMA PET/CT imaging is a promising modality for the staging of recurrent prostate cancer (PCa). Current evidence suggests limited diagnostic value of the 68Ga-PSMA PET/CT in PSA-levels ≤0.3ng/mL. Experimental data have demonstrated an increase in PSMA-expression in PCa metastases by androgen deprivation in vitro. The aim of the current study was to investigate a possible enhancing effect of PSMA with low-dose androgen deprivation in patients with BCR and low PSA-levels. Materials and Methods: Five patients with PCa and BCR, following radical prostatectomy, underwent 68Ga-PSMA PET/CT. A consecutive 68Ga-PSMA PET/CT was performed 6 to 11 days after injection of 80mg of Degarelix (Firmagon®). We recorded PSA and testosterone serum-levels and changes of PSMA-uptake in 68Ga-PSMA PET/CT images. Results: Median PSA prior 68Ga-PSMA PET/CT was 0.27ng/mL. All patients had a decrease in testosterone serum levels from median 2.95μg/l to 0.16μg/l following Degarelix injection. We observed an increase in the standardized uptake value (SUV) in PSMA-positive lymphogenous and osseous lesions in two patients following androgen deprivation. In another two patients, no PSMA positive signals were detected in either the first or the second scan. Conclusion: Our preliminary results of this feasibility assessment indicate a possible enhancing effect of PSMA-imaging induced by low-dose ADT. Despite several limitations and the small number of patients, this could be a new approach to improve staging by 68Ga-PSMA PET/CT in PCa patients with BCR after primary therapy. Further prospective studies with larger number of patients are needed to validate our findings.

2.
Int Braz J Urol ; 45(3): 459-467, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30901173

RESUMO

PURPOSE: 68Ga-PSMA PET/CT imaging is a promising modality for the staging of recurrent prostate cancer (PCa). Current evidence suggests limited diagnostic value of the 68Ga-PSMA PET/CT in PSA-levels ≤0.3ng/mL. Experimental data have demonstrated na increase in PSMA-expression in PCa metastases by androgen deprivation in vitro. The aim of the current study was to investigate a possible enhancing effect of PSMA with low-dose androgen deprivation in patients with BCR and low PSA-levels. MATERIALS AND METHODS: Five patients with PCa and BCR, following radical prostatectomy, underwent 68Ga-PSMA PET/CT. A consecutive 68Ga-PSMA PET/CT was performed 6 to 11 days after injection of 80mg of Degarelix (Firmagon®). We recorded PSA and testosterone serum-levels and changes of PSMA-uptake in 68Ga-PSMA PET/CT images. RESULTS: Median PSA prior 68Ga-PSMA PET/CT was 0.27ng/mL. All patients had a decrease in testosterone serum levels from median 2.95µg/l to 0.16µg/l following Degarelix injection. We observed an increase in the standardized uptake value (SUV) in PSMA-positive lymphogenous and osseous lesions in two patients following androgen deprivation. In another two patients, no PSMA positive signals were detected in either the fi rst or the second scan. CONCLUSION: Our preliminary results of this feasibility assessment indicate a possible enhancing effect of PSMA-imaging induced by low-dose ADT. Despite several limitations and the small number of patients, this could be a new approach to improve staging by 68Ga-PSMA PET/CT in PCa patients with BCR after primary therapy. Further prospective studies with larger number of patients are needed to validate our findings.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Glicoproteínas de Membrana , Metástase Neoplásica/diagnóstico por imagem , Compostos Organometálicos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Oligopeptídeos/uso terapêutico , Antígeno Prostático Específico/sangue , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
3.
Oncotarget ; 9(24): 16951-16961, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29682196

RESUMO

Novel treatments for castration-resistant prostate cancer (CRPC) such as abiraterone acetate (AA) or enzalutamide effectively target the androgen pathway to arrest aberrant signalling and cell proliferation. Testosterone is able to inhibit tumour cell growth in CRPC. Estrogen receptor-beta (ERß) binds the testosterone-metabolites 3ß-androstanediol and 3α-androstanediol in parallel to the canonical estradiol. In the prostate it is widely accepted that ERß regulates estrogen signalling, mediating anti-proliferative effects. We used the prostate cancer cell lines LNCaP, PC-3, VCaP, and the non-neoplastic BPH-1. VCaP cells were treated with 1 nmol/L testosterone over 20 passages, yielding the cell line VCaPrev, sensitive to hormone therapies. In contrast, LNCaP cells were grown for more than 100 passages yielding a high passage therapy resistant cell line (hiPLNCaP). VCaP and hiPLNCaP cell lines were treated with 5 µmol/L AA for more than 20 passages, respectively, generating the AA-tolerant-subtypes VCaPAA and hiPLNCaPAA. Cell lines were treated with testosterone, dihydrotestosterone (DHT), R1881, and the androgen-metabolites 3ß-androstanediol and 3α-androstanediol. 3ß-androstanediol or 3α-androstanediol significantly reduced proliferation in all cell lines except the BPH-1 and androgen receptor-negative PC-3 and markedly downregulated AR and estrogen receptor alpha (ERα). Whereas ERß expression was increased in all cell lines except BPH-1 or PC-3. In summary, 3ß-adiol or 3α-adiol, as well as DHT and R1881, significantly reduced tumour cell growth in CRPC cells. Thus, these compounds represent novel potential therapeutic approaches to overcome drug-resistance in CRPC, especially with regard to AR-V7 function in therapy resistance. Furthermore, these data confirm the tumour suppressor properties of ERß in CRPC.

4.
Oncotarget ; 8(21): 34971-34979, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28380417

RESUMO

Advanced prostate cancer can develop into castration-resistant prostate cancer (CRPC). This process is mediated either by intratumoral ligand synthesis or by mutations or aberrations of the androgen receptor (AR) or its cofactors. To date, no curative therapy for CRPC is available, as AR-targeted therapies eventually result in the development of resistance. The human prostate cancer cell line VCaP (vertebral cancer of the prostate) overexpresses AR and its splice variants (ARVs) as a mechanism of resistance to androgen-deprivation therapy (ADT) of external and intratumoral origin. In the present study, we demonstrate that stimulating estrogen receptor ß activity with the specific agonist 8ß-VE2 in VCaP cells in successive stages of ADT induced a time- and dose-dependent decrease in cell survival and an increase in apoptosis. Furthermore, 8ß-VE2 treatment reduced the overexpression of the AR as well as ARVs in VCaP cells under maximum ADT. Our results indicate that decreased survival of the androgen-dependent CRPC cells employing apoptosis together with the regulative effect on AR expression could have beneficial effects over current AR-targeting therapies.


Assuntos
Receptor beta de Estrogênio/agonistas , Neoplasias de Próstata Resistentes à Castração/genética , Receptores Androgênicos/genética , Compostos de Vinila/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
6.
Oncotarget ; 6(32): 33426-37, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26451610

RESUMO

Germ cell tumors (GCTs) are the most common malignancies in young men. Most patients with GCT can be cured with cisplatin-based combination chemotherapy, even in metastatic disease. In case of therapy resistance, prognosis is usually poor. We investigated the potential of N-cadherin inhibition as a therapeutic strategy. We analyzed the GCT cell lines NCCIT, NTERA-2, TCam-2, and the cisplatin-resistant sublines NCCIT-R and NTERA-2R. Effects of a blocking antibody or siRNA against N-cadherin on proliferation, migration, and invasion were investigated. Mouse xenografts of GCT cell lines were analyzed by immunohistochemistry for N-cadherin expression. All investigated GCT cell lines were found to express N-cadherin protein in vitro and in vivo. Downregulation of N-cadherin in vitro leads to a significant inhibition of proliferation, migration, and invasion. N-cadherin-downregulation leads to a significantly higher level of pERK. N-cadherin-inhibition resulted in significantly higher rates of apoptotic cells in caspase-3 staining. Expression of N-cadherin is preserved in cisplatin-resistant GCT cells, pointing to an important physiological role in cell survival. N-cadherin-downregulation results in a significant decrease of proliferation, migration, and invasion and stimulates apoptosis in cisplatin-naive and resistant GCT cell lines. Therefore, targeting N-cadherin may be a promising therapeutic approach, particularly in cisplatin-resistant, therapy refractory and metastatic GCT.


Assuntos
Caderinas/fisiologia , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Testiculares/genética , Animais , Apoptose/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia
7.
Springerplus ; 3: 574, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25332874

RESUMO

Recent breakthrough therapies targeting androgen receptor signalling in castration resistant prostate cancer (CRPC) involve multifunctional androgen receptor (AR) blockade and exhaustive androgen deprivation. Nevertheless, limitations to an enduring effectiveness of new drugs are anticipated in resistance mechanisms occurring under such treatments. In this study we used CRPC cell models VCaP and LNCaP as well as AR-negative PC-3- and non-neoplastic epithelial BPH-1-cells treated with 5, 10 or 25 µmol/L abiraterone hydrolyzed from abiraterone acetate (AA). The origin of CYP17A1 up-regulation under AA treatment was investigated in CRPC cell models by qRT-PCR and western-blot procedures. AA treatments of AR positive CRPC cell models led to decreased expression of androgen regulated genes such as PSA. In these cells diminished expression of androgen regulated genes was accompanied by an up-regulation of CYP17A1 expression within short-term treatments. No such effects became evident in AR-negative PC-3 cells. AR directed siRNA (siAR) used in VCaP cells significantly reduced mRNA expression and AR protein abundance. Such interference with AR signalling in the absence of abiraterone acetate also caused a marked up-regulation of CYP17A1 expression. Down-regulation of androgen regulated genes occurs in spite of an elevated expression of CYP17A1, the very target enzyme for this drug. CYP17A1 up-regulation already takes place within such short treatments with AA and does not require adaptation events over several cell cycles. CYP17A1 is also up-regulated in the absence of AA when AR signalling is physically eliminated by siAR. These results reveal an immediate counter-regulation of CYP17A1 expression whenever AR-signalling is inhibited adequately but not a persisting adaptation yielding drug resistance.

8.
J Steroid Biochem Mol Biol ; 139: 290-3, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23872207

RESUMO

Prostate cancer is the leading cause of cancer death in men of the Western world. A castration-resistant prostate cancer (CRPC) eventually will arise when a local restricted prostate carcinoma was not cured duly by radical prostatectomy or radiation therapy. Although androgen ablation therapies are considered the gold standard for treatments of advanced prostate cancer there is no curative therapy available at present. In previous pre-clinical and clinical trials several phytoestrogens were investigated for their anticancer potential in various models for prostate cancer. Phytoestrogens feature tumour preventive characteristics and most probably are involved in the low incidence rate of hormone related cancers in Asian countries. Phytoestrogens such as isoflavones can have a marked impact on the most essential therapy target of CRPC i.e. the androgen receptor. Furthermore, functional analyses solidified the notion of such drugs as androgen antagonistic. Phytoestrogens commonly feature low toxicity combined with a potential of targeted therapy. Thus, these drugs qualify for conceivable implementation in prostate cancer patients under active surveillance. In addition, relapse prevention with these drugs after radical prostatectomy or radiation therapy might be considered. This article is part of a Special Issue entitled 'Phytoestrogens'.


Assuntos
Antagonistas de Androgênios/farmacologia , Antineoplásicos Hormonais/farmacologia , Receptor beta de Estrogênio/metabolismo , Fitoestrógenos/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Antagonistas de Androgênios/uso terapêutico , Animais , Antineoplásicos Hormonais/uso terapêutico , Receptor beta de Estrogênio/agonistas , Humanos , Masculino , Terapia de Alvo Molecular , Fitoestrógenos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Transdução de Sinais
9.
Int J Oncol ; 43(5): 1385-94, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23969837

RESUMO

Phytoestrogens have been shown to exert anti-proliferative effects on different cancer cells. In addition it could be demonstrated that inhibition of proliferation is associated with downregulation of the known stem cell factors NANOG, POU5F1 and SOX2 in tumor cells. We demonstrate the potential of Belamcanda chinensis extract (BCE) and tectorigenin as anticancer drugs in cell lines of malignant testicular germ cell tumor cells (TGCT) by inhibition of proliferation and regulating the expression of stem cell factors. The TGCT cell lines TCam-2 and NTera-2 were treated with BCE or tectorigenin and MTT assay was used to measure the proliferation of tumor cells. In addition, the expression of stem cell factors was analyzed by quantitative PCR and western blot analysis. Furthermore, global expression analysis was performed by microarray technique. BCE and tectorigenin inhibited proliferation and downregulated the stem cell factors NANOG and POU5F1 in TGCT cells. In addition, gene expression profiling revealed induction of genes important for the differentiation and inhibition of oncogenes. Utilizing connectivity map in an attempt to elucidate mechanism underlying BCE treatments we found highly positive association to histone deacetylase inhibitors (HDACi) amongst others. Causing no histone deacetylase inhibition, the effects of BCE on proliferation and stem cell factors may be based on histone-independent mechanisms such as direct hyperacetylation of transcription factors. Based on these findings, phytoestrogens may be useful as new agents in the treatment of TGCT.


Assuntos
Proliferação de Células/efeitos dos fármacos , Isoflavonas/farmacologia , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Fator de Células-Tronco/metabolismo , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Perfilação da Expressão Gênica , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Testiculares/tratamento farmacológico , Células Tumorais Cultivadas
10.
Prostate ; 73(15): 1699-709, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23868789

RESUMO

BACKGROUND: The primary therapeutic target for non-organ-confined prostate cancer is the androgen receptor (AR). Main strategies to ablate AR function are androgen depletion and direct receptor blockade by AR antagonists. However, incurable castration resistant prostate cancer (CRPC) develops resistance mechanisms to cope with trace amounts of androgen including AR overexpression and mutation in the AR ligand binding domain. METHODS: The CRPC cell model VCaP derivative of a prostate cancer bone metastasis was used in vitro and in nude mice in vivo to examine the effects of immediate testosterone boost on CRPC cells. In addition, a testosterone tolerant cell model was established by incremental acclimatization of VCaP cells to 1 nM testosterone. The effects of androgen withdrawal and testosterone boosts on gene expression were assessed by quantitative real-time polymerase chain reaction, ELISA, and Western blots. Tumor cell proliferation was evaluated with a BrdU test. RESULTS: Testosterone boosts on CRPC VCaP cells eliminate tumor cells to a higher extent than androgen withdrawal in androgen tolerant cells. The pronounced decrease of tumor cell proliferation was accompanied by a marked downregulation of AR expression regarding full-length AR and splice variant AR V7. CONCLUSIONS: Acquiring castration resistance of prostate cancer cells by AR overexpression and amplification obviously sensitizes such cells to testosterone concentrations as low as physiological values. This introduces novel therapeutic means to treat CRPC with non-toxic measures and may find clinical implementation in intermittent androgen deprivation regimens.


Assuntos
Androgênios/deficiência , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Testosterona/uso terapêutico , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Neoplasias Ósseas/cirurgia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Nus , Orquiectomia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
11.
Int J Mol Med ; 31(2): 339-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23292124

RESUMO

The aim of this study was to elucidate whether the treatment of a prostate carcinoma cell line (LNCaP) and LNCaP-derived tumors with the histone deacetylase (HDAC) inhibitor valproate in combination with the mammalian target of rapamycin (mTOR) inhibitor temsirolimus resulted in synergistic effects on cell proliferation and tumor growth. LNCaP cells were treated with valproate, temsirolimus or a combination of both. The proliferation rates and the expression of key markers of tumorigenesis were evaluated. In in vivo experiments, LNCaP cells were implanted into immune-suppressed male nude mice. Mice were treated with valproate (per os), temsirolimus (intravenously) or with a combination of both. Tumor volumes were calculated and mRNA expression was quantified. The incubation of LNCaP cells with the combination of valproate and temsirolimus resulted in a decrease of cell proliferation with an additive effect of both drugs in comparison to the single treatment. In particular, the combined application of valproate and temsirolimus led to a significant upregulation of insulin-like growth factor-binding protein-3 (IGFBP-3), which mediates apoptosis and inhibits tumor cell proliferation. In the mouse model, we found no significant differences in tumor growth between the different treatment arms but immunohistological analyses showed that tumors treated with a combination of valproate and temsirolimus, but not with the single drugs alone, exhibited a significant lower proliferation capacity.


Assuntos
Inibidores de Histona Desacetilases/uso terapêutico , Próstata/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Ácido Valproico/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores de Histona Desacetilases/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Próstata/metabolismo , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Sirolimo/farmacologia , Sirolimo/uso terapêutico
12.
Carcinogenesis ; 34(5): 1115-24, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23349020

RESUMO

In this study, primary murine prostate cancer (PCa) cells were derived using the well-established TRAMP model. These PCa cells were treated with the histone deacetylase inhibitor, valproic acid (VPA), and we demonstrated that VPA treatment has an antimigrative, antiinvasive and antiproliferative effect on PCa cells. Using microarray analyses, we discovered several candidate genes that could contribute to the cellular effects we observed. In this study, we could demonstrate that VPA treatment of PCa cells causes the re-expression of cyclin D2, a known regulator that is frequently lost in PCa as we could show using immunohistochemical analyses on PCa specimens. We demonstrate that VPA specifically induces the re-expression of cyclin D2, one of the highly conserved D-type cyclin family members, in several cancer cell lines with weak or no cyclin D2 expression. Interestingly, VPA treatment had no effect in fibroblasts, which typically have high basal levels of cyclin D2 expression. The re-expression of cyclin D2 observed in PCa cells is activated by increased histone acetylation in the promoter region of the Ccnd2 gene and represents one underlying molecular mechanism of VPA treatment that inhibits the proliferation of cancer cells. Altogether, our results confirm that VPA is an anticancer therapeutic drug for the treatment of tumors with epigenetically repressed cyclin D2 expression.


Assuntos
Antineoplásicos/farmacologia , Ciclina D2/biossíntese , Neoplasias da Próstata/tratamento farmacológico , Ácido Valproico/farmacologia , Acetilação/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Ciclina D2/genética , Ciclina D2/metabolismo , Células HEK293 , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Invasividade Neoplásica , Regiões Promotoras Genéticas/efeitos dos fármacos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
13.
BMC Clin Pathol ; 12: 19, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23066729

RESUMO

BACKGROUND: Testicular germ cell tumours (TGCTs) are the most common malignancy in young men aged 18-35 years. They are clinically and histologically subdivided into seminomas and non-seminomas. Cadherins are calcium-dependent transmembrane proteins of the group of adhesion proteins. They play a role in the stabilization of cell-cell contacts, the embryonic morphogenesis, in the maintenance of cell polarity and signal transduction. N-cadherin (CDH2), the neuronal cadherin, stimulates cell-cell contacts during migration and invasion of cells and is able to suppress tumour cell growth. METHODS: Tumour tissues were acquired from 113 male patients and investigated by immunohistochemistry, as were the three TGCT cell lines NCCIT, NTERA-2 and Tcam2. A monoclonal antibody against N-cadherin was used. RESULTS: Tumour-free testis and intratubular germ cell neoplasias (unclassified) (IGCNU) strongly expressed N-cadherin within the cytoplasm. In all seminomas investigated, N-cadherin expression displayed a membrane-bound location. In addition, the teratomas and yolk sac tumours investigated also differentially expressed N-cadherin. In contrast, no N-cadherin could be detected in any of the embryonal carcinomas and chorionic carcinomas examined. This expression pattern was also seen in the investigated mixed tumours consisting of seminomas, teratomas, and embryonal carcinoma. CONCLUSIONS: N-cadherin expression can be used to differentiate embryonal carcinomas and chorionic carcinomas from other histological subtypes of TGCT.

14.
Am J Pathol ; 180(4): 1636-52, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22305861

RESUMO

Increasing evidence suggests an important function of the ß-amyloid precursor protein (APP) in malignant disease in humans; however, the biological basis for this evidence is not well understood at present. To understand the role of APP in transformed pluripotent stem cells, we studied its expression levels in human testicular germ cell tumors using patient tissues, model cell lines, and an established xenograft mouse model. In the present study, we demonstrate the cooperative expression of APP with prominent pluripotency-related genes such as Sox2, NANOG, and POU5F1 (Oct3/4). The closest homologue family member, APLP2, showed no correlation to these stem cell factors. In addition, treatment with histone deacetylase (HDAC) inhibitors suppressed the levels of APP and stem cell markers. Loss of pluripotency, either spontaneously or as a consequence of treatment with an HDAC inhibitor, was accompanied by decreased APP protein levels both in vitro and in vivo. These observations suggest that APP represents a novel and specific biomarker in human transformed pluripotent stem cells that can be selectively modulated by HDAC inhibitors.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Embrionárias de Células Germinativas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Neoplasias Testiculares/metabolismo , Adolescente , Adulto , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/farmacologia , Animais , Biomarcadores Tumorais/genética , Diferenciação Celular/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Proteínas de Choque Térmico/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/patologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia , Transcrição Genética/efeitos dos fármacos , Células Tumorais Cultivadas , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
15.
Eur J Cancer Prev ; 21(1): 55-64, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21979296

RESUMO

Various antiepileptic drugs such as valproic acid, carbamazepine, oxcarbazepine, lamotrigine and levetiracetam are known to exert histone deacetylase inhibitory (HDACi) properties, which can modify aberrantly silenced gene expression by an epigenetic mechanism. This study was initiated to examine a potential beneficial effect of these drugs on prostate cancer (PC) development. The prostate-specific antigen (PSA) levels of 106 patients under long-term treatment with antiepileptic drugs and known HDACi properties were examined. PSA represents a hallmark in the early detection of PC, and its levels may predict an invasive disease in subsequent years. For in-vitro experiments, the PC cell line LNCaP was treated with HDACi drugs; subsequently, PSA and further PC markers were assessed. When men over 50 years of age were treated with HDACi drugs they had lower age-corrected PSA levels compared with control groups, according to the following ranking: valproic acid>levetiracetam>carbamazepine/oxcarbazepine>lamotrigine. Furthermore, there was a correlation between PSA reduction and the number of HDACi drugs within the medication, lending credence to the idea that a synergistic effect might be possible. Moreover, in vitro, HDACi drugs decrease PSA on mRNA and protein levels and exhibit further oncoprotective properties.The fact that HDACi drugs exert antiproliferative effects on neoplastic cells in vitro and in vivo, which are paralleled by expression alterations of aberrantly regulated genes, underlines the potential therapeutic value of HDACi drugs. These data suggest that long-term HDACi treatment can positively influence the characteristically slow transformation of tumour precursor cells in the prostate and may thus reduce a patient's risk of developing PC.


Assuntos
Anticonvulsivantes/uso terapêutico , Inibidores de Histona Desacetilases/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Ácido Valproico/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/etiologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
16.
Int J Colorectal Dis ; 26(1): 37-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20931209

RESUMO

PURPOSE: Laparoscopic surgery in the treatment of colon carcinoma causes pH value alterations as well as changes in fibrinolytic activity. This results in enhanced proliferation of colon carcinoma cells in vitro and also in enhanced growth of liver metastasis when compared to isobaric (gasless) laparoscopy in vivo. So far, the direct influence of CO(2) pneumoperitoneum on the invasiveness and metastatic capabilities of colon cancer cells remains unclear. We therefore evaluated transcripts of the uPA system. METHODS: The influence of CO(2) pneumoperitoneum on the gene expression of plasminogen activator inhibitor-1 (PAI-1), urokinase-type plasminogen activator (uPA), and tissue-type plasminogen activator (tPA) was investigated in colon carcinoma cell lines (HT116, SW48, and WiDr) and mesothelial cells employing a pneumoperitoneum chamber in vitro. Quantitative gene expression data were collected using real-time RT-PCR and statistical analysis was performed by means of analysis of variance and Bonferroni correction. RESULTS: The expression of uPA and PAI-1 was increased in colon carcinoma cell lines when cultivated at pH 6.1, a value corresponding to intraabdominal pH values during CO(2) insufflation. Elevated PAI-1 mRNA levels were also observed when CO(2) was simultaneously applied with a pressure of 10 mmHg. In contrast, there were no significant changes in mesothelial cells in the investigated parameter. CONCLUSION: The conditions of CO(2) pneumoperitoneum cause changes in the expression of genes controlling the fibrinolytic activity. The increase of PAI-1 and uPA can contribute to the enhancement of metastasis and invasive potential of tumour cells. Therefore, changes in the conditions of laparoscopy may well optimise laparoscopic therapy in colon cancer.


Assuntos
Dióxido de Carbono/farmacologia , Neoplasias do Colo/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Pneumoperitônio/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Epitélio/efeitos dos fármacos , Epitélio/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/genética , Pneumoperitônio/genética , Pneumoperitônio/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Circ Res ; 106(4): 695-704, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20044516

RESUMO

RATIONALE: We previously discovered the human 10T-->C (Trp4Arg) missense mutation in exon 2 of the muscle LIM protein (MLP, CSRP3) gene. OBJECTIVE: We sought to study the effects of this single-nucleotide polymorphism in the in vivo situation. METHODS AND RESULTS: We now report the generation and detailed analysis of the corresponding Mlp(W4R/+) and Mlp(W4R/W4R) knock-in animals, which develop an age- and gene dosage-dependent hypertrophic cardiomyopathy and heart failure phenotype, characterized by almost complete loss of contractile reserve under catecholamine induced stress. In addition, evidence for skeletal muscle pathology, which might have implications for human mutation carriers, was observed. Importantly, we found significantly reduced MLP mRNA and MLP protein expression levels in hearts of heterozygous and homozygous W4R-MLP knock-in animals. We also detected a weaker in vitro interaction of telethonin with W4R-MLP than with wild-type MLP. These alterations may contribute to an increased nuclear localization of W4R-MLP, which was observed by immunohistochemistry. CONCLUSIONS: Given the well-known high frequency of this mutation in Caucasians of up to 1%, our data suggest that (W4R-MLP) might contribute significantly to human cardiovascular disease.


Assuntos
Cardiomiopatia Hipertrófica/metabolismo , Insuficiência Cardíaca/metabolismo , Proteínas Musculares/metabolismo , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Função Ventricular Esquerda , Fatores Etários , Envelhecimento , Animais , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/fisiopatologia , Células Cultivadas , Conectina , Modelos Animais de Doenças , Fibrose , Técnicas de Introdução de Genes , Genótipo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Heterozigoto , Homozigoto , Proteínas com Domínio LIM , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutação de Sentido Incorreto , Miócitos Cardíacos/patologia , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
18.
Prostate ; 69(12): 1257-69, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19459176

RESUMO

BACKGROUND: A prostate cancer (PCa) biomarker with improved specificity relative to PSA is a public health priority. Hypermethylated DNA can be detected in body fluids from PCa patients and may be a useful biomarker, although clinical performance varies between studies. We investigated the performance of candidate PCa DNA methylation biomarkers identified through a genome-wide search. METHODS: Real-time PCR was used to measure four DNA methylation biomarkers: GSTP1 and three previously unreported candidates associated with the genes RASSF2, HIST1H4K, and TFAP2E in sodium bisulfite-modified DNA. Matched plasma and urine collected prospectively from 142 patients referred for prostate biopsy and 50 young asymptomatic males were analyzed. RESULTS: Analysis of all biomarkers in urine DNA significantly discriminated PCa from biopsy negative patients. The biomarkers discriminated PCa from biopsy negative patients with AUCs ranging from 0.64 for HIST1H4K (95% CI 0.55-0.72, P < 0.00001) to 0.69 for GSTP1 (95% CI 0.60-0.77, P < 0.00001). All biomarkers showed minimal correlation with PSA. Multivariate analysis did not yield a panel that significantly improved performance over that of single biomarkers. All biomarkers showed greater sensitivity for PCa in urine than in plasma DNA. CONCLUSIONS: Analysis of the biomarkers in urine DNA significantly discriminated PCa from biopsy negative patients. The biomarkers provided information independent of PSA and may warrant inclusion in nomograms for predicting prostate biopsy outcome. The biomarkers' PCa sensitivity was greater for urine than plasma DNA. The biomarker performances in urine DNA should next be validated in formal training and test studies.


Assuntos
Biomarcadores Tumorais/urina , Metilação de DNA , Neoplasias da Próstata/urina , Urinálise/métodos , Adulto , Idoso , Biomarcadores Tumorais/genética , Citodiagnóstico , DNA/metabolismo , Glutationa S-Transferase pi/urina , Histonas/urina , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Fator de Transcrição AP-2/urina , Proteínas Supressoras de Tumor/urina , Adulto Jovem
19.
Radiat Oncol ; 3: 19, 2008 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-18625043

RESUMO

BACKGROUND: As the majority of prostate cancers (PC) express estrogen receptors, we evaluated the combination of radiation and estrogenic stimulation (estrogen and genistein) on the radiosensitivity of PC cells in vitro. METHODS: PC cells LNCaP (androgen-sensitive) and PC-3 (androgen-independent) were evaluated. Estrogen receptor (ER) expression was analyzed by means of immunostaining. Cells were incubated in FCS-free media with genistein 10 microM and estradiol 10 microM 24 h before irradiation and up to 24 h after irradiation. Clonogenic survival, cell cycle changes, and expression of p21 were assessed. RESULTS: LNCaP expressed both ER-alpha and ER-beta, PC-3 did not. Incubation of LNCaP and PC-3 with genistein resulted in a significant reduction of clonogenic survival. Incubation with estradiol exhibited in low concentrations (0.01 microM) stimulatory effects, while higher concentrations did not influence survival. Both genistein 10 microM and estradiol 10 microM increased low-dose hyper-radiosensitivity [HRS] in LNCaP, while hormonal incubation abolished HRS in PC-3. In LNCaP cells hormonal stimulation inhibited p21 induction after irradiation with 4 Gy. In PC-3 cells, the proportion of cells in G2/M was increased after irradiation with 4 Gy. CONCLUSION: We found an increased HRS to low irradiation doses after incubation with estradiol or genistein in ER-alpha and ER-beta positive LNCaP cells. This is of high clinical interest, as this tumor model reflects a locally advanced, androgen dependent PC. In contrast, in ER-alpha and ER-beta negative PC-3 cells we observed an abolishing of the HRS to low irradiation doses by hormonal stimulation. The effects of both tested compounds on survival were ER and p53 independent. Since genistein and estradiol effects in both cell lines were comparable, neither ER- nor p53-expression seemed to play a role in the linked signalling. Nevertheless both compounds targeted the same molecular switch. To identify the underlying molecular mechanisms, further studies are needed.


Assuntos
Antineoplásicos/farmacologia , Estradiol/farmacologia , Genisteína/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Tolerância a Radiação/efeitos dos fármacos , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Masculino , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/radioterapia , Receptores Estrogênicos/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco
20.
Mol Endocrinol ; 22(7): 1606-21, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18451096

RESUMO

In the present study, we demonstrate that leupaxin mRNA is overexpressed in prostate cancer (PCa) as compared with normal prostate tissue by using cDNA arrays and quantitative RT-PCR analyses. Moderate to strong expression of leupaxin protein was detected in approximately 22% of the PCa tissue sections analyzed, and leupaxin expression intensities were found to be significantly correlated with Gleason patterns/scores. In addition, different leupaxin expression levels were observed in PCa cell lines, and at the subcellular level, leupaxin was usually localized in focal adhesion sites. Furthermore, mutational analysis and transfection experiments of LNCaP cells using different green fluorescent protein-leupaxin constructs demonstrated that leupaxin contains functional nuclear export signals in its LD3 and LD4 motifs, thus shuttling between the cytoplasm and the nucleus. We could also demonstrate for the first time that leupaxin interacts with the androgen receptor in a ligand-dependent manner and serves as a transcriptional activator of this hormone receptor in PCa cells. Down-regulation of leupaxin expression using RNA interference in LNCaP cells resulted in a high rate of morphological changes, detachment, spontaneous apoptosis, and a reduction of prostate-specific antigen secretion. In contrast, knockdown of leupaxin expression in androgen-independent PC-3 and DU 145 cells induced a significant decrease of both the invasive capacity and motility. Our results therefore indicate that leupaxin could serve as a potential progression marker for a subset of PCa and may represent a novel coactivator of the androgen receptor. Leupaxin could function as a putative target for therapeutic interventions of a subset of advanced PCa.


Assuntos
Carcinoma/metabolismo , Moléculas de Adesão Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Fosfoproteínas/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Motivos de Aminoácidos , Adesão Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Progressão da Doença , Humanos , Masculino , Invasividade Neoplásica , Interferência de RNA , Regulação para Cima
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