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1.
J Cancer Res Clin Oncol ; 150(2): 63, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300343

RESUMO

PURPOSE: Skeletal metastases are increasingly reported in metastatic triple-negative breast cancer (BC) patients. We previously reported that TGF-ß1 sustains activating transcription factor 3(ATF3) expression and is required for cell proliferation, invasion, and bone metastasis genes. Increasing studies suggest the critical regulatory function of microRNAs (miRNAs) in governing BC pathogenesis. TGF-ß1 downregulated the expression of miR-4638-3p, which targets ATF3 in human BC cells (MDA-MB-231). In the present study, we aimed to identify the functional role of miR-4638-3p in BC bone metastasis by the caudal artery injection of the MDA-MB-231 cells overexpressing mir-4638 in the mice. METHODS: MDA-MB-231 cells overexpressing miR-4638 were prepared by stable transfections. Reverse transcriptase quantitative PCR was carried out to determine the expression of endogenous miR-4638-3p and bone resorption marker genes. X-ray, micro-CT, and Hematoxylin & Eosin studies were used to determine osteolytic lesions, trabecular structure, bone mineral density, and micrometastasis of cells. RESULTS: The mice injected with MDA-MB-231 cells overexpressing miR-4638-3p decreased the expression of bone resorption marker genes, compared to MDA-MB-231 cells injection. Reduced osteolytic lesions and restored bone density by MDA-MB-231 cells overexpressing miR-4638-3p were observed. Similarly, the mice injected with MDA-MB-231 cells overexpressing miR-4638-3p showed a better microarchitecture of the trabecular network. A few abnormal cells seen in the femur of MDA-MB-231 cells-injected mice were not found in MDA-MB-231 cells overexpressing miR-4638. CONCLUSION: The identified functional role of ATF3 targeting miR-4638-3p in BC bone metastasis in vivo suggests its candidature as BC therapeutics in the future.


Assuntos
Neoplasias Ósseas , Reabsorção Óssea , MicroRNAs , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Fator de Crescimento Transformador beta1 , MicroRNAs/genética , Micrometástase de Neoplasia , Neoplasias Ósseas/genética
2.
Curr Protein Pept Sci ; 23(10): 672-683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111757

RESUMO

Nuclear factor erythroid 2 (NFE 2) - related factor 2 (NFE2L2 or NRF2) is one of the transcription factors predominantly related to the expression of antioxidant genes. NRF2 plays a pivotal role in controlling redox potential in several tumor characteristics, including cancer cell metabolism, stem-cell-like characteristics, tumor aggressiveness, invasion, and metastasis. Further, it was recently discovered that the noncanonical pathway of NRF2 activation was involved in carcinogenesis. Cancerrelated changes (e.g., metabolic flexibility) that support cancer progression were found to be redox and NRF2 dependent. The pro or antineoplastic effects of NRF2 are essentially based on the specific molecular characteristics of the type of cancer. Therefore, systematic investigation of NRF2 signaling is necessary to clarify its role in cancer etiology. Understanding the role of NRF2 in triggering gene expressions in different types of cancer is quite challenging, which might be useful to target those genes for better clinical outcomes. To decipher the role of NRF2 in tumor formation and progression, largescale genomic and transcriptomic studies are required to correlate the clinical outcomes with the activity of the NRF2 expression system. This review attempts to give insights into the understanding of the role of NRF2 in cancer.


Assuntos
Fator 2 Relacionado a NF-E2 , Neoplasias , Humanos , Carcinogênese/metabolismo , Neoplasias/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Transdução de Sinais
3.
Colloids Surf B Biointerfaces ; 218: 112767, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36007314

RESUMO

This study attempts to improve the aqueous solubility of chitosan and utilizes it in the fabrication of composites with hydroxyapatite (HAP). The composites were evaluated as a curcumin delivery vehicle for bone regeneration. The chitosan was modified by quaternization, with a quaternization degree of 5 % for low quaternized chitosan (LQC) and 11 % for high quaternized chitosan (HQC). The modified chitosan, at alkaline pH 11, facilitated in situ HAP growth and formed LQC-HAP and HQC-HAP composites. The quaternization weakens intermolecular hydrogen bonds, facilitates interaction with the apatite precursor ions and promotes the growth of HAP. The modification significantly improved drug encapsulation (2.6 fold) but at the cost of a slight decrease in mechanical strength and increase in drug release. The in vitro studies with human osteoblast-like MG-63 cells established that the curcumin-loaded composites, LQC-HAP-C and HQC-HAP-C are biocompatible, encourage proliferation and promote a 2-fold increase in calcium mineralization over drug-free composites. The study exemplifies the reciprocity between quaternization degree and drug load/release properties and also illustrates that the magnitude of the latter reflects bioactivity. Thus, the quaternized chitosan-based HAP composite with tailorable bio-physicochemical properties becomes an interesting drug delivery system in bone regeneration.


Assuntos
Quitosana , Curcumina , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cálcio , Quitosana/química , Curcumina/farmacologia , Durapatita/química , Humanos , Engenharia Tecidual , Tecidos Suporte/química
5.
Curr Mol Med ; 22(6): 549-561, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34463227

RESUMO

BACKGROUND: The dynamic changes that bone undergoes during the ensemble of remodeling are administered by vital factors like Runx2 (a bone transcription factor) and matrix metalloproteinases (MMPs). AIMS: Parathyroid hormone (PTH), an FDA approved drug for bone-related ailments, was seen to stimulate MMP-13 expression via Runx2 to ultimately aid in the bone remodeling process. MicroRNAs (miRNAs) have been shown to play a major role in controlling bone metabolism, and the use of miRNAs has recently become promising therapeutic avenues for the treatment of many diseases, including bone disorders. Thus, in this study, we attempted to investigate and evaluate the expression of MMP-13 via a miRNA profile targeting Runx2 under PTH-regulation in rat osteoblastic cells. METHODS: PTH stimulated the expression of MMP-13 mRNA significantly at 4 h in rat osteoblastic cells (UMR106-01). Runx2 was required for PTH-stimulation of MMP-13 expression, in silico scrutiny generated 14 unique miRNAs targeting Runx2, and among these miRNAs, miR-290 was significantly downregulated by PTH-treatment in UMR106- 01 cells and in rat primary osteoblasts. RESULTS: Overexpression of miR-290 decreased the expression of Runx2, the binding of Runx2 at the MMP-13 promoter, and the expression of MMP-13 mRNA in PTH-treated UMR106-01 cells. A dual luciferase reporter assay identified the direct targeting of Runx2 mRNA by miR-290 in these cells. CONCLUSION: Our findings indicate that the PTH-responsive miR-290 regulated Runx2- mediated MMP-13 expression in rat osteoblastic cells, suggesting miR-290 as a molecular marker or target in bone and bone-related diseases.


Assuntos
MicroRNAs , Hormônio Paratireóideo , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/farmacologia , RNA Mensageiro/metabolismo , Ratos
6.
Clin Radiol ; 76(10): 784.e17-784.e25, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34266658

RESUMO

Perianal fistulas affect approximately 2 in 10,000 people, causing symptoms such as pain and discharge, which can have a debilitating effect on a patient's quality of life. Surgical treatment, which can offer a potential cure or palliation of symptoms, must be considered carefully in cases with extensive sphincter involvement. In complex cases, the use of preoperative magnetic resonance imaging (MRI) can help to determine the best course of operative action. This review describes common and contemporary surgical procedures for perianal fistula, highlighting technical features, as well as important surgical considerations associated with each method and how these can be assessed radiologically. We focus on the anatomical features and MRI findings that take procedural elements into account and help determine the most appropriate method of treatment. The aim of this article is to provide a basis for informed and focused discussion between surgeons and radiologists to ensure the most appropriate procedure is selected for each case, with the ultimate aim of obtaining the most favourable outcomes for patients.


Assuntos
Imageamento por Ressonância Magnética/métodos , Fístula Retal/diagnóstico por imagem , Fístula Retal/cirurgia , Canal Anal/diagnóstico por imagem , Canal Anal/cirurgia , Humanos
7.
Int J Biol Macromol ; 132: 541-549, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30951775

RESUMO

Transforming growth factor-beta1 (TGF-ß1) is a pleiotropic and ubiquitous cytokine involved in bone development and bone remodeling. Matrix metalloproteinase-13 (MMP13) plays a role in the degradation of the extracellular matrix (ECM), and the regulation of this gene is critical in bone remodeling. We previously reported that TGF-ß1 stimulates MMP13 expression in rat osteoblasts. Recently, studies have examined the regulation of bone metabolism by microRNAs (miRNAs) to determine their therapeutic potential in osteogenesis. Here, we assessed the effect of TGF-ß1 on down-regulation of miRNAs that target MMP13 and stimulation of MMP13 expression in osteoblasts. We used in silico analysis and identified 11 specific miRNAs which directly target rat MMP13. Among these miRNAs, miR-203a-5p expression was significantly decreased by TGF-ß1-treatment in rat osteoblasts. Transient transfection of a miR-203a-5p mimic into rat osteoblasts reduced MMP13 expression. A luciferase reporter assay confirmed a direct targeting of miR-miR-203a-5p with the 3' untranslated regions of the MMP13 gene. Hence, we suggest that TGF-ß1 stimulated down-regulation of miR-203a-5p, resulting in the stimulation of MMP13 expression in rat osteoblasts. Thus, identification of the role of miR-203a-5p via TGF-ß1 and MMP13 in bone remodeling indicated its potential as a biomarker or therapeutic agent for treating bone and bone-related diseases.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Metaloproteinase 13 da Matriz/genética , MicroRNAs/genética , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Linhagem Celular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ratos
8.
Colorectal Dis ; 21(1): 73-78, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30218632

RESUMO

INTRODUCTION: Restorative proctocolectomy has gained acceptance in the surgical management of medically refractive ulcerative colitis and cancer prevention in familial adenomatous polyposis. Incontinence following restorative proctocolectomy occurs in up to 25% of patients overnight. The Renew® insert is an inert single-use device which acts as an anal plug. The aim of this study was to assess the acceptability, effectiveness and safety of the Renew® insert in patients who have undergone restorative proctocolectomy. The device has yet to be assessed in patients who have undergone restorative proctocolectomy. METHOD: This was a prospective study exploring the acceptability, effectiveness and safety of the Renew® insert in improving incontinence in patients who had undergone restorative proctocolectomy. A total of 15 patients with incontinence were asked to use the Renew® insert for 14 days following their standard care. The Incontinence Questionnaire-Bowels was used pre- and posttreatment to assess response and patients were asked to report the perceived acceptability, effectiveness and safety of the device at the end of the trial. RESULTS: The device was acceptable to 8/15 (53%) of patients and was effective in 6/15 (40%). Only 2/15 (13%) of patients raised any safety concerns, and these were minor. The device was associated with a significant reduction in night seepage (P = 0.034). CONCLUSION: In a small study, the Renew® insert can be both acceptable and effective and is also associated with few safety concerns. It is also associated with significant reductions in night-time seepage.


Assuntos
Colite Ulcerativa/cirurgia , Equipamentos e Provisões , Incontinência Fecal/terapia , Aceitação pelo Paciente de Cuidados de Saúde , Complicações Pós-Operatórias/terapia , Proctocolectomia Restauradora , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
10.
Colorectal Dis ; 18(10): 983-988, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26924721

RESUMO

AIM: Full-thickness laparo-endoscopic excision (FLEX) is a new technique developed for the full-thickness excision of colonic adenomas and, potentially, early cancer, avoiding the need for colectomy. FLEX requires accurate preoperative characterization of three key morphological features of the tumour, including its relation to the mesenteric border, its diameter and the circumferential extent of involvement of the bowel wall. This study evaluated the accuracy of CT colonography (CTC) for the assessment of these features in early colonic tumours. METHOD: Consecutive patients undergoing CTC prior to colonic resection for complex benign polyps or UICC Stage 1 cancer were retrospectively analysed by two specialist gastrointestinal radiologists blinded to the subsequent histopathological findings. The location of the tumour in relation to the mesenteric border, its maximum diameter and the circumferential extent of involvement of the colonic wall were correlated with the histopathological examination of the surgical resection specimen. Pearson's correlation coefficient (r) and Kappa agreement (κ) were used to compare the maximum diameter and the circumferential extent of involvement of the colonic wall. RESULTS: Twenty-eight patients with early colonic neoplasia were included. All had had a surgical segmental resection. Four had a benign adenoma and 24 had a TNM Stage 1 cancer. Histopathological assessment of the resected surgical specimen showed that 21 of the 28 lesions were located on the mesenteric border. The median diameter was 35 (interquartile range 28-42) mm; 13 lesions involved less than one-third of the circumference, 11 between one and two-thirds and four more than two-thirds. CTC correctly identified the location of the lesion in relation to the mesenteric border in all 28 cases. Correlation between CTC and histopathology was good for the assessment of the maximum diameter of the lesion (r = 0.81) and the circumferential extent of involvement of the colonic wall (κ = 0.76). CONCLUSION: CTC can accurately assess the key morphological features for the selection of patients with early colonic neoplasia for full-thickness laparo-endoscopic excision.


Assuntos
Colo/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Seleção de Pacientes , Idoso , Idoso de 80 Anos ou mais , Colectomia/métodos , Colo/patologia , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Colonografia Tomográfica Computadorizada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Método Simples-Cego
11.
Clin Radiol ; 69(6): 597-605, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24589446

RESUMO

AIM: To describe our experience using a 5 year audit of computed tomography colonography (CTC) practice and identify factors that influence diagnostic performance to guide implementation in other centres. MATERIAL AND METHODS: Consecutive patients referred for CTC at a single institution over a 5 year period were identified, and reporting rates and positive predictive value (PPV) calculated for small polyps, large polyps, and colorectal cancer. Diagnostic performance was compared using the Chi-squared test, and trends over time were examined with logistic regression. The effect of faecal tagging and an intravenous spasmolytic were investigated using Fisher's exact test. RESULTS: In total, 4355 CTC examinations were performed. Overall reporting rates and PPV were 17% and 92%, respectively. Negative predictive value (NPV) for cancer was 99.9%. A significant decrease in reporting rate (p < 0.001) was accompanied by an increase in PPV for small polyps (p = 0.02) following the introduction of faecal tagging. Adequacy rates for CTC improved over time (96% to 99%), with improved adequacy rates when using a spasmolytic, 98% versus 96% without. A significant difference in reporting rates, but not PPV, was found between radiologists. CONCLUSION: Accurate colonic investigation using CTC can be delivered safely to a high-risk patient population at a single centre. Faecal tagging and an intravenous spasmolytic improve diagnostic performance.


Assuntos
Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Neoplasias Colorretais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Agendamento de Consultas , Catárticos/administração & dosagem , Colonoscopia/estatística & dados numéricos , Meios de Contraste/administração & dosagem , Atenção à Saúde/estatística & dados numéricos , Fezes/química , Feminino , Humanos , Infusões Intravenosas , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Variações Dependentes do Observador , Equipe de Assistência ao Paciente , Valor Preditivo dos Testes , Encaminhamento e Consulta/estatística & dados numéricos , Reino Unido , Adulto Jovem
12.
Br J Radiol ; 85(1015): 876-86, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22553291

RESUMO

CT enterography is a new non-invasive imaging technique that offers superior small bowel visualisation compared with standard abdomino-pelvic CT, and provides complementary diagnostic information to capsule endoscopy and MRI enterography. CT enterography is well tolerated by patients and enables accurate, efficient assessment of pathology arising from the small bowel wall or surrounding organs. This article reviews the clinical role of CT enterography, and offers practical tips for optimising technique and accurate interpretation.


Assuntos
Hemorragia Gastrointestinal/diagnóstico por imagem , Enteropatias/diagnóstico por imagem , Intestino Delgado/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Intensificação de Imagem Radiográfica/métodos , Adulto , Idoso , Endoscopia por Cápsula/métodos , Meios de Contraste , Feminino , Hemorragia Gastrointestinal/patologia , Humanos , Enteropatias/patologia , Neoplasias Intestinais/diagnóstico por imagem , Neoplasias Intestinais/patologia , Intestino Delgado/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/efeitos adversos , Efeitos da Radiação , Medição de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/métodos
13.
Clin Radiol ; 65(12): 958-66, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21070898

RESUMO

With the recent publication of international computed tomography (CT) colonography standards, which aim to improve quality of examinations, this review informs radiologists about the significance of flat polyps (adenomas and hyperplastic polyps) in colorectal cancer pathways. We describe flat polyp classification systems and propose how flat polyps should be reported to ensure patient management strategies are based on polyp morphology as well as size. Indeed, consistency when describing flat polyps is of increasing importance given the strengthening links between CT colonography and endoscopy.


Assuntos
Pólipos Adenomatosos/diagnóstico por imagem , Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/normas , Neoplasias Colorretais/diagnóstico por imagem , Radiologia/normas , Pólipos Adenomatosos/classificação , Pólipos Adenomatosos/patologia , Pólipos do Colo/classificação , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/classificação , Neoplasias Colorretais/patologia , Humanos , Guias de Prática Clínica como Assunto/normas
14.
Clin Radiol ; 65(12): 997-1004, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21070904

RESUMO

AIMS: To evaluate the efficacy of a new intensive "hands-on" course designed to train small teams of radiographers in computed tomography colonography (CTC) technique and initial interpretation for patient triage. MATERIALS AND METHODS: The course comprised small-group lectures, active participation in the daily CTC service with practical technique and image interpretation training by experienced radiologists and radiographers. Evaluation was by assessment of knowledge using randomized sets of multiple choice questions (MCQ; pre/post-course), practical technique using checklists and expert global scores, and interpretation performance outcomes using randomized pre/post-course test datasets (five validated CTC examinations each). Paired t-tests were used to investigate change in performance for MCQ score and interpretation accuracy. RESULTS: Thirteen courses with 49 participants were evaluated over 2 years. Practical skills were high, with mean (SD) checklist scores of 14/15 (0.85) and global scores of 26/30 (2.3). MCQ scores increased significantly from a mean of 59% pre-course to 69% post-course, p<0.001. Correct classification of CTC examination improved significantly from a mean of 55% pre-course to 71% post-course, p<0.001. Cancer and large polyp (>10mm) detection rates also improved significantly from 49% to 60%, p=0.002. CONCLUSION: Structured training in CTC can significantly improve knowledge and interpretation skills of radiographers, while assessing safe procedural performance. Implementation of similar programmes nationally may help reduce performance gaps between centres.


Assuntos
Competência Clínica/normas , Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/normas , Educação Médica Continuada/normas , Radiologia/educação , Pólipos do Colo/classificação , Colonografia Tomográfica Computadorizada/métodos , Educação Médica Continuada/métodos , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Reino Unido
15.
Toxicology ; 241(3): 99-105, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17889981

RESUMO

Environmental pollutants that disrupt endocrine system might also affect the modeling and remodeling of bone. Environmental factors, irrespective of age and sex contribute for the development of secondary osteoporosis. Polychlorinated biphenyls have adverse effects on various organs including bone. The present study was designed to investigate the effects of PCB (Aroclor 1254) on femur bone and the ameliorative role of vitamin C or E. In this regard, four groups of adult male albino rats were used as control, PCB (2mg/kgb.wt.), PCB+vitamin C (100mg/kgb.wt.) and PCB+vitamin E (50mg/kgb.wt.). The bone formation markers (ALP, Collagen), bone resorption marker (TRAP), antioxidant enzymes (SOD, GPX and GST) and lipid peroxidation in the femur were studied. Aroclor 1254 treatment decreased the ALP activity and collagen, but increased the TRAP activity and lipid peroxidation. While it decreased the SOD and GPX activity, GST was unaltered. Interestingly, simultaneous administration of vitamin C or E prevented the adverse effects of Aroclor 1254 in the femur. In conclusion, the present investigation suggests that Aroclor 1254 induced oxidative stress affects femoral bone metabolism. However, vitamin C or vitamin E protected the femur from the oxidative stress.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Fêmur , Estresse Oxidativo/efeitos dos fármacos , Fosfatase Ácida/metabolismo , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Peso Corporal/efeitos dos fármacos , Colágeno/metabolismo , Fêmur/efeitos dos fármacos , Fêmur/enzimologia , Fêmur/metabolismo , Isoenzimas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato , Vitamina E/farmacologia
16.
Clin Chim Acta ; 377(1-2): 70-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17083925

RESUMO

BACKGROUND: Previous studies have indicated that estrogen administration in the advanced stage of prostate cancer provide some benefits to the patients. Estrogen action was thought to be mediated via the blockade of the pituitary-testicular axis that effectively lowered the circulating levels of androgen and, thus, results in tumor regression; however, the effect of estrogens on prostate epithelial cells is still unclear. We investigated the effects of estradiol on insulin-like growth factor type I receptor (IGF-IR), IGF-binding protein 3 (IGFBP-3), IGFBP-4, and matrix metalloproteinase 2 (MMP-2) and MMP-9 in androgen-independent prostate cancer cells (PC-3). METHODS: The cells were treated with different concentrations of estradiol (1, 10 and 100 nmol/l) for different time periods (24, 48, 72 and 96 h). Cell proliferation was assessed using MTT assay, and IGFBP-3 and IGFBP-4 were assessed using immunoradiometric and enzyme immunoassays, respectively. MMP-2, MMP-9 and IGF-IR expression levels were analyzed using western-blot analysis, and MMP-2 and MMP-9 activities were analyzed using gelatin zymography. Apoptosis was confirmed by Annexin V-FITC and acridine orange and ethidium bromide staining methods. DNA fragmentation studies were also performed. RESULTS: Cell proliferation assay revealed that 10 and 100 nmol/l estradiol concentrations inhibit the proliferation of PC-3 cells when incubated for 48-96 h. The secretory levels of IGFBP-3 and IGFBP-4 were increased significantly. The western-blot results showed that estradiol is capable of decreasing the expression of MMP-2 and MMP-9 significantly. Gelatin zymography showed that activities of MMP-2 and MMP-9 are decreased in estradiol-treated cells. Estradiol-induced apoptosis was studied using annexin V-binding and propidium iodide influx. Estradiol also induced nuclear fragmentation in higher doses (100 nmol/l) in PC-3 cells. CONCLUSION: Inhibition of MMPs in cancer cells and increased levels of IGFBP-3 and IGFBP-4 associated with apoptosis may be one of the targets for anticancer function of estradiol. Estradiol inhibits the proliferation of prostate cancer cells by inducing apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Estradiol/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Somatomedinas/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino
17.
Oncol Res ; 16(2): 67-74, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16898267

RESUMO

Quercetin, a flavonoid found in onion, grapes, green vegetables, etc., has been shown to possess potent antiproliferative effects against various malignant cells. We report insulin-like growth factor-binding protein-3 (IGFBP-3) as an effector of quercetin-induced apoptosis in human prostate cancer cell lines in a p53-independent manner. We evaluated the production of IGFBP-3 in quercetin-treated cells. Apoptosis was studied in quercetin-treated cells to study the IGFBP-3-mediated role with flow cytometry and DNA fragmentation. Protein expressions of Bcl-2, Bcl-x(L), and Bax were studied by Western blot. Increased production of IGFBP-3 was associated with the increased ratio of proapoptotic to antiapoptotic members of the Bcl-2 family. In quercetin-treated PC-3 cells, an increase in Bax protein expression and a decrease in Bcl-x(L) protein and Bcl-2 protein were observed. As PC-3 is a p53-negative cell line, these modulations of proapoptotic proteins and induction of apoptosis were independent of p53. The level of IGFBP-3 on the response of PC-3 cells to quercetin was examined. There was a twofold increase in IGFBP-3 level in conditioned media of 100 microM quercetin-treated cells. Quercetin also brought a peak at sub-G1 in PC-3 cells. Thus, increased level of IGFBP-3 was associated with increased proapoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells via its modulation of the Bax/Bcl-2 protein ratio.


Assuntos
Apoptose/efeitos dos fármacos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Quercetina/farmacologia , Linhagem Celular Tumoral , Forma Celular , Humanos , Masculino , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Toxicology ; 220(1): 63-70, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16406255

RESUMO

The habitual consumption of even moderate quantities of alcoholic beverages is clearly associated with reduced bone mass, increased prevalence of skeletal fracture and also it is the major risk factor for the development of secondary osteoporosis. The present in vitro study was designed to determine the dose response effects of ethanol on osteoblast-like human osteosarcoma cells (SaOS-2) proliferation, differentiation, mineralization and cyto-toxicity. SaOS-2 cells were plated in 48 and 6 well culture plates and exposed to different concentrations of ethanol (1, 10, 100, 200 and 300 mM) for 24, 48 and 72 h. At the end of incubation, proliferation of cells was studied using crystal violet Bioassay. The cell lysate was utilized to determine ALP activity and conditioned media were used to measure LDH activity. Histochemical localization of ALP and mineralized nodules were studied from cells treated with ethanol (10 and 100 mM) for 21 days. At higher doses, there was a significant reduction in cell number, whereas at lower doses there were variable effects. In 24 h treatment, the higher doses showed a significant increase in ALP activity, whereas 48 and 72 h treatments showed an opposite trend. Ethanol treatment caused a dose- and time-dependent increase in LDH activity. Ethanol treatment altered the quality of mineralization at 10 mM dose whereas completely inhibited mineralization at 100 mM dose, despite the presence of serum. In conclusion, the toxic effect of ethanol is reflected on cell proliferation, differentiation and mineralization even at low doses and at extended treatment duration.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Calcinose/induzido quimicamente , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Etanol/toxicidade , Osteossarcoma/tratamento farmacológico , Fosfatase Alcalina/metabolismo , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/metabolismo , Relação Dose-Resposta a Droga , Humanos , L-Lactato Desidrogenase/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteossarcoma/metabolismo , Osteossarcoma/patologia
19.
Waste Manag ; 26(1): 22-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16287597

RESUMO

This study examines the potential reuse of textile effluent treatment plant (ETP) sludge in building materials. The physico-chemical and engineering properties of a composite textile sludge sample from the southern part of India have been studied. The tests were conducted as per Bureau of Indian Standards (BIS) specification codes to evaluate the suitability of the sludge for structural and non-structural application by partial replacement of up to 30% of cement. The cement-sludge samples failed to meet the required strength for structural applications. The strength and other properties met the Bureau of Indian Standards for non-structural materials such as flooring tiles, solid and pavement blocks, and bricks. Results generally meet most ASTM standards for non-structural materials, except that the sludge-amended bricks do not meet the Grade NW brick standard. It is concluded that the substitution of textile ETP sludge for cement, up to a maximum of 30%, may be possible in the manufacturing of non-structural building materials. Detailed leachability and economic feasibility studies need to be carried out as the next step of research.


Assuntos
Conservação dos Recursos Naturais , Materiais de Construção , Resíduos Industriais , Têxteis , Força Compressiva , Teste de Materiais , Metais Pesados/análise , Esgotos/análise , Água/análise
20.
J Cancer Res Clin Oncol ; 131(11): 765-71, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16049707

RESUMO

Prostate cancer is the major health problem and the leading cause of male cancer death. Quercetin is a novel antitumor and antioxidant, whose molecular mechanism involved in cell cycle arrest in androgen independent prostate cancer cells remains unclear. In this study, we investigated the effects of quercetin on proliferation and cell cycle arrest by modulation of Cdc2/Cdk-1 protein in prostate cancer cells (PC-3). PC- 3 cells are human androgen independent cancer cells and were cultured with quercetin at concentrations of 50 and 100 microM for 24 h. Cell proliferation, apoptosis and cell cycle distribution were analyzed. Expression of Cdc2/Cdk-1, cyclin B1, cyclin A, p21/Cip1, pRb, pRb2/p130, Bcl-2, Bcl-X(L), Bax and caspase-3 proteins were studied with western blot analysis. Addition of quercetin led to substantial decrease in the expression of Cdc2/Cdk-1, cyclin B1 and phosphorylated pRb and increase in p21. Flowcytometric analysis showed that quercetin blocks G2-M transition, with significant induction of apoptosis. Apoptosis markers like Bcl-2 and Bcl-X(L) were significantly decreased and Bax and caspase-3 were increased. From this study, it was concluded that quercetin inhibits prostate cancer cell proliferation by altering the expression of cell cycle regulators and apoptotic proteins.


Assuntos
Antineoplásicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Quercetina/farmacologia , Proteína do Retinoblastoma/metabolismo , Biomarcadores Tumorais/metabolismo , Western Blotting , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Fosforilação , Neoplasias da Próstata/metabolismo
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