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1.
PLoS One ; 16(4): e0248859, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33831014

RESUMEN

In response to personal protective equipment (PPE) shortages in the United States due to the Coronavirus Disease 2019, two models of N95 respirators were evaluated for reuse after gamma radiation sterilization. Gamma sterilization is attractive for PPE reuse because it can sterilize large quantities of material through hermetically sealed packaging, providing safety and logistic benefits. The Gamma Irradiation Facility at Sandia National Laboratories was used to irradiate N95 filtering facepiece respirators to a sterilization dose of 25 kGy(tissue). Aerosol particle filtration performance testing and electrostatic field measurements were used to determine the efficacy of the respirators after irradiation. Both respirator models exhibited statistically significant decreases in particle filtering efficiencies and electrostatic potential after irradiation. The largest decrease in capture efficiency was 40-50% and peaked near the 200 nm particle size. The key contribution of this effort is correlating the electrostatic potential change of individual filtration layer of the respirator with the decrease filtration efficiency after irradiation. This observation occurred in both variations of N95 respirator that we tested. Electrostatic potential measurement of the filtration layer is a key indicator for predicting filtration efficiency loss.


Asunto(s)
COVID-19/prevención & control , Rayos gamma , Respiradores N95/virología , SARS-CoV-2 , Esterilización , Inactivación de Virus/efectos de la radiación , COVID-19/transmisión , Humanos , Estados Unidos
2.
Biomedicines ; 8(12)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33316876

RESUMEN

Focal therapies such as high-intensity focused ultrasound (HiFU) are an emerging therapeutic option for prostate cancer (PCA). Thermal or mechanical effects mediate most therapies. Moreover, locally administered drugs such as bicalutamide or docetaxel are new focal therapeutic options. We assessed the impact of such focal medical treatments on cell viability and heat sensitivity by pre-treating PCA cell lines and then gradually exposing them to heat. The individual heat response of the cell lines tested differed largely. Vertebral-Cancer of the Prostate (VCaP) cells showed an increase in metabolic activity at 40-50 °C. Androgen receptor (AR)-negative PC3 cells showed an increase at 51.3 °C and were overall more resistant to higher temperatures. Pre-treatment of VCaP cells with testosterone (VCaPrev) leads to a more PC3-like kinetic of the heat response. Pre-treatment with finasteride and bicalutamide did not cause changes in heat sensitivity in any cell line. Mitoxantrone treatment, however, shifted heat-induced proliferation loss to lower temperature in VCaP cells. Further analysis via RNAseq identified a possible correlation of heat resistance with H3K27me3-dependent gene regulation, which could be related to an increase in the histone methyltransferase EZH2 and a possible neuroendocrine differentiation. Pre-treatment with mitoxantrone might be a perspective for HiFU treatment. Further studies are needed to evaluate possible combinations with Hsp90 or EZH2 inhibitors.

3.
Int. braz. j. urol ; 45(3): 459-467, May-June 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1012312

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Anciano , Compuestos Organometálicos , Neoplasias de la Próstata/patología , Glicoproteínas de Membrana , Radiofármacos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Antagonistas de Andrógenos/uso terapéutico , Metástasis de la Neoplasia/diagnóstico por imagen , Oligopéptidos/uso terapéutico , Valores de Referencia , Factores de Tiempo , Reproducibilidad de los Resultados , Antígeno Prostático Específico/sangre , Clasificación del Tumor , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología
4.
Int Braz J Urol ; 45(3): 459-467, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30901173

RESUMEN

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.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Glicoproteínas de Membrana , Metástasis de la Neoplasia/diagnóstico por imagen , Compuestos Organometálicos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/patología , Radiofármacos , Anciano , Isótopos de Galio , Radioisótopos de Galio , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Recurrencia Local de Neoplasia/patología , Oligopéptidos/uso terapéutico , Antígeno Prostático Específico/sangre , Valores de Referencia , Reproducibilidad de los Resultados , Factores de Tiempo
5.
Oncotarget ; 9(24): 16951-16961, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29682196

RESUMEN

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.

6.
Oncotarget ; 8(21): 34971-34979, 2017 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-28380417

RESUMEN

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.


Asunto(s)
Receptor beta de Estrógeno/agonistas , Neoplasias de la Próstata Resistentes a la Castración/genética , Receptores Androgénicos/genética , Compuestos de Vinilo/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba
8.
Oncotarget ; 6(32): 33426-37, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26451610

RESUMEN

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.


Asunto(s)
Cadherinas/fisiología , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias Testiculares/genética , Animales , Apoptosis/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patología
9.
Springerplus ; 3: 574, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25332874

RESUMEN

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.

10.
J Steroid Biochem Mol Biol ; 139: 290-3, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23872207

RESUMEN

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'.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Antineoplásicos Hormonales/farmacología , Receptor beta de Estrógeno/metabolismo , Fitoestrógenos/farmacología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Antagonistas de Andrógenos/uso terapéutico , Animales , Antineoplásicos Hormonales/uso terapéutico , Receptor beta de Estrógeno/agonistas , Humanos , Masculino , Terapia Molecular Dirigida , Fitoestrógenos/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Transducción de Señal
11.
Int J Oncol ; 43(5): 1385-94, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23969837

RESUMEN

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.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Isoflavonas/farmacología , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias de Células Germinales y Embrionarias/patología , Fitoestrógenos/farmacología , Extractos Vegetales/farmacología , Factor de Células Madre/metabolismo , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Perfilación de la Expresión Génica , Humanos , Masculino , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Testiculares/tratamiento farmacológico , Células Tumorales Cultivadas
12.
Prostate ; 73(15): 1699-709, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23868789

RESUMEN

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.


Asunto(s)
Andrógenos/deficiencia , Neoplasias Óseas/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Testosterona/uso terapéutico , Animales , Neoplasias Óseas/genética , Neoplasias Óseas/secundario , Neoplasias Óseas/cirugía , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Desnudos , Orquiectomía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía
13.
Carcinogenesis ; 34(5): 1115-24, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23349020

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Ciclina D2/biosíntesis , Neoplasias de la Próstata/tratamiento farmacológico , Ácido Valproico/farmacología , Acetilación/efectos de los fármacos , Animales , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Ciclina D2/genética , Ciclina D2/metabolismo , Células HEK293 , Inhibidores de Histona Desacetilasas/farmacología , Histonas/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Invasividad Neoplásica , Regiones Promotoras Genéticas/efectos de los fármacos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología
14.
Int J Mol Med ; 31(2): 339-46, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23292124

RESUMEN

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.


Asunto(s)
Inhibidores de Histona Desacetilasas/uso terapéutico , Próstata/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Sirolimus/análogos & derivados , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Ácido Valproico/uso terapéutico , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sinergismo Farmacológico , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Masculino , Ratones , Ratones Desnudos , Próstata/metabolismo , Neoplasias de la Próstata/patología , Inhibidores de Proteínas Quinasas/farmacología , Sirolimus/farmacología , Sirolimus/uso terapéutico
15.
BMC Clin Pathol ; 12: 19, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23066729

RESUMEN

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.

16.
Am J Pathol ; 180(4): 1636-52, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22305861

RESUMEN

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.


Asunto(s)
Precursor de Proteína beta-Amiloide/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de Células Germinales y Embrionarias/metabolismo , Células Madre Pluripotentes/metabolismo , Neoplasias Testiculares/metabolismo , Adolescente , Adulto , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/farmacología , Animales , Biomarcadores de Tumor/genética , Diferenciación Celular/efectos de los fármacos , Transformación Celular Neoplásica/metabolismo , Chaperón BiP del Retículo Endoplásmico , Proteínas de Choque Térmico/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Humanos , Masculino , Ratones , Ratones Desnudos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/patología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Recombinantes/farmacología , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Testiculares/patología , Transcripción Genética/efectos de los fármacos , Células Tumorales Cultivadas , Ácido Valproico/farmacología , Ácido Valproico/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto Joven
17.
Eur J Cancer Prev ; 21(1): 55-64, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21979296

RESUMEN

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.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Inhibidores de Histona Desacetilasas/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Ácido Valproico/uso terapéutico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/etiología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
18.
Int J Colorectal Dis ; 26(1): 37-43, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20931209

RESUMEN

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.


Asunto(s)
Dióxido de Carbono/farmacología , Neoplasias del Colon/metabolismo , Inhibidor 1 de Activador Plasminogénico/metabolismo , Neumoperitoneo/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/genética , Epitelio/efectos de los fármacos , Epitelio/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/genética , Neumoperitoneo/genética , Neumoperitoneo/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo
19.
Circ Res ; 106(4): 695-704, 2010 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-20044516

RESUMEN

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.


Asunto(s)
Cardiomiopatía Hipertrófica/metabolismo , Insuficiencia Cardíaca/metabolismo , Proteínas Musculares/metabolismo , Contracción Miocárdica , Miocitos Cardíacos/metabolismo , Función Ventricular Izquierda , Factores de Edad , Envejecimiento , Animales , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/fisiopatología , Células Cultivadas , Conectina , Modelos Animales de Enfermedad , Fibrosis , Técnicas de Sustitución del Gen , Genotipo , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/fisiopatología , Heterocigoto , Homocigoto , Proteínas con Dominio LIM , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Mutación Missense , Miocitos Cardíacos/patología , Fenotipo , Polimorfismo de Nucleótido Simple , ARN Mensajero/metabolismo , Ratas , Proteínas Recombinantes de Fusión/metabolismo , Transfección
20.
Prostate ; 69(12): 1257-69, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19459176

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor/orina , Metilación de ADN , Neoplasias de la Próstata/orina , Urinálisis/métodos , Adulto , Anciano , Biomarcadores de Tumor/genética , Citodiagnóstico , ADN/metabolismo , Gutatión-S-Transferasa pi/orina , Histonas/orina , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Antígeno Prostático Específico/sangre , Factor de Transcripción AP-2/orina , Proteínas Supresoras de Tumor/orina , Adulto Joven
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