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1.
Environ Pollut ; 247: 917-926, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30823346

RESUMO

Manufactured nanoparticles (MNPs) undergo transformation immediately after they enter wastewater treatment streams and during their partitioning to sewage sludge, which is applied to agricultural soils in form of biosolids. We examined toxicogenomic responses of the model nematode Caenorhabditis elegans to pristine and transformed ZnO-MNPs (phosphatized pZnO- and sulfidized sZnO-MNPs). To account for the toxicity due to dissolved Zn, a ZnSO4 treatment was included. Transformation of ZnO-MNPs reduced their toxicity by nearly ten-fold, while there was almost no difference in the toxicity of pristine ZnO-MNPs and ZnSO4. This combined with the fact that far more dissolved Zn was released from ZnO- compared to pZnO- or sZnO-MNPs, suggests that dissolution of pristine ZnO-MNPs is one of the main drivers of their toxicity. Transcriptomic responses at the EC30 for reproduction resulted in a total of 1161 differentially expressed genes. Fifty percent of the genes differentially expressed in the ZnSO4 treatment, including the three metal responsive genes (mtl-1, mtl-2 and numr-1), were shared among all treatments, suggesting that responses to all forms of Zn could be partially attributed to dissolved Zn. However, the toxicity and transcriptomic responses in all MNP treatments cannot be fully explained by dissolved Zn. Two of the biological pathways identified, one essential for protein biosynthesis (Aminoacyl-tRNA biosynthesis) and another associated with detoxification (ABC transporters), were shared among pristine and one or both transformed ZnO-MNPs, but not ZnSO4. When comparing pristine and transformed ZnO-MNPs, 66% and 40% of genes were shared between ZnO-MNPs and sZnO-MNPs or pZnO-MNPs, respectively. This suggests greater similarity in transcriptomic responses between ZnO-MNPs and sZnO-MNPs, while toxicity mechanisms are more distinct for pZnO-MNPs, where 13 unique biological pathways were identified. Based on these pathways, the toxicity of pZnO-MNPs is likely to be associated with their adverse effect on digestion and metabolism.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Poluentes do Solo/toxicidade , Óxido de Zinco/toxicidade , Animais , Caenorhabditis elegans/genética , Esgotos , Transcriptoma/efeitos dos fármacos , Sulfato de Zinco/química
2.
Prostate ; 77(16): 1583-1591, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29063620

RESUMO

INTRODUCTION: Epithelial-mesenchymal-transition (EMT) has been previously identified as a contributor to prostate cancer progression to metastasis and therapeutic resistance to antiandrogens and radiotherapy. In this study we conducted a retrospective analysis to investigate the significance of radiation-induced EMT and consequential changes to the tumor microenvironment in biochemical recurrence and response to radiotherapy in prostate cancer patients. METHODS: Expression profiling and localization for EMT effectors, E-Cadherin, N-Cadherin, ß-catenin and Vimentin was assessed in human prostate tumor specimens pre- and post-radiotherapy and correlated with biochemical recurrence. In addition, immunoreactivity of the DNA repair enzyme, polymerase (PARP-1) and the cytoskeletal-remodeling regulator, cofilin was evaluated in prostate tumor specimens pre- and post-radiotherapy and correlated with pre-treatment prostate-specific antigen levels (PSA). RESULTS: Our findings identified that characteristic changes associated with the EMT phenotype and its reversal to mesenchymal-epithelial-transition (MET) within the tumor microenvironment correlate with biochemical recurrence and resistance to radiotherapy among prostate cancer patients. Moreover, elevated PARP-1 expression among the tumor cells undergoing EMT implicates that DNA repair mechanisms may potentially reverse the cytotoxic effects of radiotherapy-induced DNA breaks. CONCLUSIONS: Our results suggest that EMT programming effectors, integrated with the actin cytoskeleton regulator cofilin and mesenchymal PARP-1 expression profile provide a signature of potential predictive significance of therapeutic response to radiotherapy in a subset of prostate cancer patients.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Poli(ADP-Ribose) Polimerase-1/biossíntese , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Tolerância a Radiação/fisiologia , Idoso , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Poli(ADP-Ribose) Polimerase-1/genética , Valor Preditivo dos Testes , Neoplasias da Próstata/genética , Estudos Retrospectivos
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