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1.
Mol Carcinog ; 54(9): 730-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24615813

RESUMO

Tumor microenvironment (TM) is an essential element in prostate cancer (PCA), offering unique opportunities for its prevention. TM includes naïve fibroblasts that are recruited by nascent neoplastic lesion and altered into 'cancer-associated fibroblasts' (CAFs) that promote PCA. A better understanding and targeting of interaction between PCA cells and fibroblasts and inhibiting CAF phenotype through non-toxic agents are novel approaches to prevent PCA progression. One well-studied cancer chemopreventive agent is silibinin, and thus, we examined its efficacy against PCA cells-mediated differentiation of naïve fibroblasts into a myofibroblastic-phenotype similar to that found in CAFs. Silibinin's direct inhibitory effect on the phenotype of CAFs derived directly from PCA patients was also assessed. Human prostate stromal cells (PrSCs) exposed to control conditioned media (CCM) from human PCA PC3 cells showed more invasiveness, with increased alpha-smooth muscle actin (α-SMA) and vimentin expression, and differentiation into a phenotype we identified in CAFs. Importantly, silibinin (at physiologically achievable concentrations) inhibited α-SMA expression and invasiveness in differentiated fibroblasts and prostate CAFs directly, as well as indirectly by targeting PCA cells. The observed increase in α-SMA and CAF-like phenotype was transforming growth factor (TGF) ß2 dependent, which was strongly inhibited by silibinin. Furthermore, induction of α-SMA and CAF phenotype by CCM were also strongly inhibited by a TGFß2-neutralizing antibody. The inhibitory effect of silibinin on TGFß2 expression and CAF-like biomarkers was also observed in PC3 tumors. Together, these findings highlight the potential usefulness of silibinin in PCA prevention through targeting the CAF phenotype in the prostate TM.


Assuntos
Anticarcinógenos/farmacologia , Fibroblastos/efeitos dos fármacos , Próstata/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/prevenção & controle , Silimarina/farmacologia , Fator de Crescimento Transformador beta2/metabolismo , Anticarcinógenos/química , Antioxidantes/química , Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Masculino , Silybum marianum/química , Próstata/citologia , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Silibina , Silimarina/química
2.
Nanomaterials (Basel) ; 13(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513151

RESUMO

In this work, copper (II) ions were saturated and copper oxide nanoparticles (CuO NPs) were supported in natural zeolite from Chile; this was achieved by making the adsorbent material come into contact with a copper ion precursor solution and using mechanical agitation, respectively. The kinetic and physicochemical process of the adsorption of copper ions in the zeolite was studied, as well as the effect of the addition of CuO NPs on the antibacterial properties. The results showed that the saturation of copper (II) ions in the zeolite is an efficient process, obtaining a 27 g L-1 concentration of copper ions in a time of 30 min. The TEM images showed that a good dispersion of the CuO NPs was obtained via mechanical stirring. The material effectively inhibited the growth of Gram-negative and Gram-positive bacteria that have shown resistance to methicillin and carbapenem. Furthermore, the zeolite saturated with copper at the same concentration had a better bactericidal effect than the zeolite supported with CuO NPs. The results suggested that the ease of processing and low cost of copper (II) ion-saturated zeolitic material could potentially be used for dental biomedical applications, either directly or as a bactericidal additive for 3D printing filaments.

3.
Mol Cancer Res ; 20(4): 607-621, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34992146

RESUMO

There is a continued need to identify novel therapeutic targets to prevent the mortality associated with prostate cancer. In this context, mitochondrial Rho GTPase 2 (MIRO2) mRNA was upregulated in metastatic prostate cancer compared with localized tumors, and higher MIRO2 levels were correlated with poor patient survival. Using human cell lines that represent androgen-independent or -sensitive prostate cancer, we showed that MIRO2 depletion impaired cell growth, colony formation, and tumor growth in mice. Network analysis of MIRO2's binding partners identified metabolism and cellular responses to extracellular stimuli as top overrepresented pathways. The top hit on our screen, General Control Nonderepressible 1 (GCN1), was overexpressed in prostate cancer, and interacted with MIRO2 in prostate cancer cell lines and in primary prostate cancer cells. Functional analysis of MIRO2 mutations present in patients with prostate cancer led to the identification of MIRO2 159L, which increased GCN1 binding. Importantly, MIRO2 was necessary for efficient GCN1-mediated GCN2 kinase signaling and induction of the transcription factor activating transcription factor 4 (ATF4) levels. Further, MIRO2's effect on regulating prostate cancer cell growth was mediated by ATF4. Finally, levels of activated GCN2 and ATF4 were correlated with MIRO2 expression in prostate cancer xenografts. Both MIRO2 and activated GCN2 levels were higher in hypoxic areas of prostate cancer xenografts. Overall, we propose that targeting the MIRO2-GCN1 axis may be a valuable strategy to halt prostate cancer growth. IMPLICATIONS: MIRO2/GCN1/GCN2 constitute a novel mitochondrial signaling pathway that controls androgen-independent and androgen-sensitive prostate cancer cell growth.


Assuntos
Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Transativadores/metabolismo
4.
Hum Mol Genet ; 18(7): 1368-75, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19153072

RESUMO

A single nucleotide polymorphism (SNP) at 10q11 (rs10993994) in the 5' region of the MSMB gene was recently implicated in prostate cancer risk in two genome-wide association studies. To identify possible causal variants in the region, we genotyped 16 tagging SNPs and imputed 29 additional SNPs in approximately 65 kb genomic region at 10q11 in a Swedish population-based case-control study (CAncer of the Prostate in Sweden), including 2899 cases and 1722 controls. We found evidence for two independent loci, separated by a recombination hotspot, associated with prostate cancer risk. Among multiple significant SNPs at locus 1, the initial SNP rs10993994 was most significant. Importantly, using an MSMB promoter reporter assay, we showed that the risk allele of this SNP had only 13% of the promoter activity of the wild-type allele in a prostate cancer model, LNCaP cells. Curiously, the second, novel locus (locus 2) was within NCOA4 (also known as ARA70), which is known to enhance androgen receptor transcriptional activity in prostate cancer cells. However, its association was only weakly confirmed in one of the three additional study populations. The observations that rs10993994 is the strongest associated variant in the region and its risk allele has a major effect on the transcriptional activity of MSMB, a gene with previously described prostate cancer suppressor function, together suggest the T allele of rs10993994 as a potential causal variant at 10q11 that confers increased risk of prostate cancer.


Assuntos
Cromossomos Humanos Par 10/genética , Predisposição Genética para Doença , Mapeamento Físico do Cromossomo , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , Proteínas Secretadas pela Próstata/genética , Androgênios/farmacologia , Sequência de Bases , Humanos , Masculino , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Suécia
5.
Brain Cogn ; 77(3): 345-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22032805

RESUMO

Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH(+), and 10 without, WMH(-)) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH(+) and WMH(-) - in right parietal and bilateral temporal areas. Both WMH(-) and WMH(+) MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH(+) is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood.


Assuntos
Poluição do Ar/efeitos adversos , Encéfalo/patologia , Transtornos Cognitivos/induzido quimicamente , Cognição , Inflamação/induzido quimicamente , Criança , Transtornos Cognitivos/patologia , Feminino , Humanos , Inflamação/patologia , Testes de Inteligência , Imageamento por Ressonância Magnética , Masculino , México , Fibras Nervosas Mielinizadas/patologia , Testes Neuropsicológicos , Tamanho do Órgão , Estudos Prospectivos
6.
Mol Cancer Res ; 19(7): 1123-1136, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33846123

RESUMO

Prostate cancer genomic subtypes that stratify aggressive disease and inform treatment decisions at the primary stage are currently limited. Previously, we functionally validated an aggressive subtype present in 15% of prostate cancer characterized by dual deletion of MAP3K7 and CHD1. Recent studies in the field have focused on deletion of CHD1 and its role in androgen receptor (AR) chromatin distribution and resistance to AR-targeted therapy; however, CHD1 is rarely lost without codeletion of MAP3K7. Here, we show that in the clinically relevant context of co-loss of MAP3K7 and CHD1 there are significant, collective changes to aspects of AR signaling. Although CHD1 loss mainly impacts the expansion of the AR cistrome, loss of MAP3K7 drives increased AR target gene expression. Prostate cancer cell line models engineered to cosuppress MAP3K7 and CHD1 also demonstrated increased AR-v7 expression and resistance to the AR-targeting drug enzalutamide. Furthermore, we determined that low protein expression of both genes is significantly associated with biochemical recurrence (BCR) in a clinical cohort of radical prostatectomy specimens. Low MAP3K7 expression, however, was the strongest independent predictor for risk of BCR over all other tested clinicopathologic factors including CHD1 expression. Collectively, these findings illustrate the importance of MAP3K7 loss in a molecular subtype of prostate cancer that poses challenges to conventional therapeutic approaches. IMPLICATIONS: These findings strongly implicate MAP3K7 loss as a biomarker for aggressive prostate cancer with significant risk for recurrence that poses challenges for conventional androgen receptor-targeted therapies.


Assuntos
DNA Helicases/genética , Proteínas de Ligação a DNA/genética , MAP Quinase Quinase Quinases/genética , Neoplasias da Próstata/genética , Interferência de RNA , Receptores Androgênicos/genética , Transdução de Sinais/genética , Androgênios/farmacologia , Benzamidas/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Logísticos , MAP Quinase Quinase Quinases/metabolismo , Masculino , Recidiva Local de Neoplasia , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Fatores de Risco
7.
Am Surg ; 76(10): 1088-91, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21105616

RESUMO

Completion axillary lymph node dissection (CLND) is presently the standard of care after a positive sentinel lymph node biopsy (SLNB). We hypothesize that the incidence of axillary recurrence in patients who do not undergo CLND for micrometastases is low, and CLND is not necessary for locoregional control. We performed a retrospective chart review of patients with invasive breast carcinoma and micrometastases detected on SLNB. The Memorial Sloan Kettering Nomogram (MSKN) predicting the likelihood of nonsentinel lymph node (NSN) metastases was compared with the incidence of positive NSN. There were 61 patients identified with a mean follow-up of 70 months. The average tumor size was 2 cm. The median number of positive SLNs was one. Twenty-eight (46%) patients had a CLND; of these, 20 patients had one positive NSN (2 of 28 [7%]) and the mean MSKN score was 12 per cent. There were 33 (54%) patients who had SLNB alone, and their mean MSKN score was 13 per cent. Axillary recurrence in this group was 1.6 per cent. We conclude the incidence of axillary recurrence in patients with micrometastases detected by SLN biopsy who do not undergo CLND is low. The use of a predictive nomogram to estimate likelihood of metastatic disease to NSN may overestimate the actual incidence of positive NSN in patients with micrometastases.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Excisão de Linfonodo , Recidiva Local de Neoplasia/epidemiologia , Adulto , Idoso , Axila , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos
8.
Waste Manag ; 113: 270-279, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32559697

RESUMO

Modeling approaches are generally used to describe mercury transformations in a single step of flue gas treatment processes. However, less attention has been given to the interactions between the different process stages. Accordingly, the mercury removal performance of a full-scale solid waste incineration plant, equipped with a dry flue gas treatment line was investigated using two complementary modeling strategies: a thermochemical equilibrium approach to study the mercury transformation mechanisms and speciation in the flue gas, and a kinetic approach to describe the mercury adsorption process. The modeling observations were then compared to real-operation full-scale data. Considering the typical flue gas composition of waste incineration facilities (high concentrations of HCl compared to Hg), it was found that a process temperature decrease results in better mercury removal efficiencies, associated with a higher oxidation extent of Hg in HgCl2, and the enhancement of the sorbent capacity. Improvements can also be attained by increasing the sorbent injection rate to the process, or the solid/gas separation cycles. An empirical correlation to predict the mercury removal efficiency from the main operating parameters of dry flue gas treatment units was proposed, representing a useful tool for waste incineration facilities. The presented modeling approach proved to be suitable to evaluate the behavior of full-scale gas treatment units, and properly select the most adequate adjustments in operating parameters, in order to respect the increasingly constraining mercury emissions regulations.


Assuntos
Poluentes Atmosféricos/análise , Mercúrio/análise , Adsorção , Incineração , Oxirredução , Resíduos Sólidos
9.
J Urol ; 181(5): 2146-51, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19296982

RESUMO

PURPOSE: Genetic causes of nephrolithiasis are underestimated. Primary hyperoxaluria type 2 is a rare autosomal recessive disease caused by mutations in the GRHPR gene, leading to an accumulation of oxalate and L-glycerate with recurrent kidney stone formation and nephrocalcinosis, and the later development of renal failure and systemic oxalate depositions. We studied the effects of a novel GRHPR mutation on GRHPR enzymatic activity and molecular modeling. MATERIALS AND METHODS: Genomic DNA from a 50-year-old male with a late diagnosis of primary hyperoxaluria type 2 was extracted, analyzed and compared with the established human GRHPR gene sequence. Restriction enzyme analysis of the patient, 30 healthy controls and 30 patients with nephrolithiasis of various causes was done to confirm the presence of the mutation. GRHPR activity was analyzed by site directed mutagenesis of WT and mutant clones. We studied the effects of the mutation on enzymatic molecular modeling. RESULTS: We found the novel homozygous single missense mutation A975G in exon 9, creating an amino acid change from asparagine to aspartic acid in position 312. No mutations were detected in restriction enzyme analysis in all 30 healthy controls and 30 patients with nephrolithiasis of various causes. Transfected cells with the mutant clone showed abolished GRHPR activity. Molecular modeling studies revealed that the mutation was likely to disrupt the correct folding of the GRHPR substrate binding domain, hence affecting the enzyme active site. CONCLUSIONS: Primary hyperoxaluria type 2 should be considered in patients at adult stone clinics who have had a history of nephrolithiasis since childhood, especially in those with consanguineous parents. Biochemical analysis followed by mutation identification should be the approach for making the definitive diagnosis of primary hyperoxaluria type 2.


Assuntos
Oxirredutases do Álcool/genética , Hiperoxalúria Primária/enzimologia , Hiperoxalúria Primária/genética , Mutação de Sentido Incorreto , Oxirredutases do Álcool/metabolismo , Análise Mutacional de DNA , Ativação Enzimática , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Hiperoxalúria Primária/diagnóstico , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Fatores de Tempo
10.
Stem Cells ; 26(3): 600-10, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18055450

RESUMO

Demonstration of the hallmarks of stem cells, self-renewal and multilineage differentiation, is a challenge that has not been met for numerous tissues postulated to possess adult stem cells, including prostate tissue. Using a defined medium, we reproducibly isolated and maintained adult mouse prostatic cells with characteristics of progenitor/stem cells. Clonal populations of cells demonstrated tissue-specific multilineage differentiation by their ability to generate organized prostatic ductal structures in vivo, with luminal and basal cell layers, when grafted under the renal capsules of mice in the presence of fetal rat urogenital mesenchyme. Complete differentiation was demonstrated by the expression and secretion of terminally differentiated prostatic secretory products into the lumens. Self-renewal was demonstrated by serial transplantation of clonal populations that generated fully differentiated ductal structures in vivo. In vitro, undifferentiated cells expressed markers associated with prostate stem cells, including Sca 1 and CD49f, as well as basal cell markers (p63 and cytokeratins 5 and 14) and, at a low level, luminal cell markers (androgen receptor and cytokeratins 8 and 18). When grafted and allowed to differentiate in the presence of fetal urogenital mesenchyme, the cells differentiated into luminal cells and basal cells with more restricted protein expression patterns. These studies are the first to report a reproducible system to assess adult prostatic progenitor/stem cells.


Assuntos
Diferenciação Celular , Linhagem da Célula , Próstata/citologia , Células-Tronco/citologia , Animais , Ataxina-1 , Ataxinas , Biomarcadores/metabolismo , Proliferação de Células , Células Cultivadas , Células Clonais , Ensaio de Unidades Formadoras de Colônias , Células Epiteliais/citologia , Humanos , Integrina alfa6/metabolismo , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Ratos , Recombinação Genética/genética , Regeneração
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