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1.
J Cell Sci ; 134(7)2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33712453

RESUMO

Poly(A) polymerases add the poly(A) tail at the 3' end of nearly all eukaryotic mRNA, and are associated with proliferation and cancer. To elucidate the role of the most-studied mammalian poly(A) polymerase, poly(A) polymerase α (PAPOLA), in cancer, we assessed its expression in 221 breast cancer samples and found it to correlate strongly with the aggressive triple-negative subtype. Silencing PAPOLA in MCF-7 and MDA-MB-231 breast cancer cells reduced proliferation and anchorage-independent growth by decreasing steady-state cyclin D1 (CCND1) mRNA and protein levels. Whereas the length of the CCND1 mRNA poly(A) tail was not affected, its 3' untranslated region (3'UTR) lengthened. Overexpressing PAPOLA caused CCND1 mRNA 3'UTR shortening with a concomitant increase in the amount of corresponding transcript and protein, resulting in growth arrest in MCF-7 cells and DNA damage in HEK-293 cells. Such overexpression of PAPOLA promoted proliferation in the p53 mutant MDA-MB-231 cells. Our data suggest that PAPOLA is a possible candidate target for the control of tumor growth that is mostly relevant to triple-negative tumors, a group characterized by PAPOLA overexpression and lack of alternative targeted therapies.


Assuntos
Neoplasias da Mama , Ciclina D1 , Animais , Neoplasias da Mama/genética , Proliferação de Células/genética , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Poliadenilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Clin Nephrol ; 85(1): 44-54, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26587779

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs) have been implicated in the pathophysiology of various renal diseases, however, there are limited data regarding their role in renal AL-amyloidosis. In the present study, we evaluated the glomerular expression of MMPs in renal-biopsy specimens containing AL-amyloid deposits. We also examined the association of MMPs with renal function at the time of diagnostic renal biopsy. METHODS: We performed immunohistochemistry with monoclonal antibodies against MMP-1, MMP-2, MMP-3, MMP-9, and TIMP-1 in 19 kidney-biopsy specimens with AL-amyloidosis and 8 specimens from normal kidney tissue. We used clinical data of the patients at the time of kidney biopsy to evaluate the association between MMP expression and renal function. RESULTS: We found increased MMP-1 and MMP-3 expression within the amyloid deposits and adjacent tissues in > 50% of the amyloid-positive biopsies, whereas MMP-1 and MMP-3 were negative in control samples. In contrast, we found no significant glomerular MMP-2 and TIMP-1 expression in amyloid-containing or normal kidneys. MMP-9 expression was found in the glomerular basement membrane equally in AL-amyloidosis and control specimens. The presence of MMP-1 and MMP-3 in the glomeruli of patients with AL-amyloidosis correlated with worse renal function at the time of kidney biopsy. CONCLUSION: The findings of this study show increased glomerular expression of MMP-1 and MMP-3 in patients with AL-amyloidosis which is associated with worse renal function at the time of the kidney biopsy. Our results suggest an important role for MMP-1 and MMP-3 in the pathogenesis of renal damage in AL-amyloidosis.


Assuntos
Amiloidose/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Nefropatias/metabolismo , Glomérulos Renais/química , Glomérulos Renais/patologia , Metaloproteinases da Matriz/análise , Paraproteinemias/metabolismo , Idoso , Amiloide/análise , Amiloidose/complicações , Biópsia/efeitos adversos , Feminino , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina , Imuno-Histoquímica , Nefropatias/etiologia , Nefropatias/fisiopatologia , Masculino , Metaloproteinase 1 da Matriz/análise , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 3 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Paraproteinemias/complicações , Inibidor Tecidual de Metaloproteinase-1/análise
3.
Ann Rheum Dis ; 73(10): 1854-63, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23873874

RESUMO

OBJECTIVES: Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is characterised by neutrophil activation. An elevated prevalence of venous thromboembolic events has been reported in AAV. Because of the critical role of neutrophils in inflammation associated thrombosis, we asked whether neutrophil tissue factor (TF) may be implicated in the thrombotic diathesis in AAV. METHODS: Neutrophils from four patients and sera from 17 patients with ANCA associated vasculitis with active disease and remission were studied. TF expression was assessed by immunoblotting and confocal microscopy. Circulating DNA levels were evaluated. TF expressing microparticles (MPs) were measured by flow cytometry and thrombin-antithrombin complex levels by ELISA. RESULTS: Peripheral blood neutrophils from four patients with active disease expressed elevated TF levels and released TF expressing neutrophil extracellular traps (NETs) and MPs. TF positive NETs were released by neutrophils isolated from the bronchoalveolar lavage and were detected in nasal and renal biopsy specimens. Elevated levels of circulating DNA and TF expressing neutrophil derived MPs were further observed in sera from patients with active disease. Induction of remission attenuated the aforementioned effects. Control neutrophils treated with sera from patients with active disease released TF bearing NETs and MPs which were abolished after IgG depletion. Treatment of control neutrophils with isolated IgG from sera from patients with active disease also resulted in the release of TF bearing NETs. TF implication in MP dependent thrombin generation was demonstrated by antibody neutralisation studies. CONCLUSIONS: Expression of TF in NETs and neutrophil derived MPs proposes a novel mechanism for the induction of thrombosis and inflammation in active AAV.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/sangue , Micropartículas Derivadas de Células/metabolismo , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Trombofilia/etiologia , Tromboplastina/fisiologia , Adulto , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Anticorpos Anticitoplasma de Neutrófilos/sangue , Líquido da Lavagem Broncoalveolar/citologia , Estudos de Casos e Controles , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Ativação de Neutrófilo , Indução de Remissão , Trombofilia/metabolismo , Tromboplastina/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores
4.
Ren Fail ; 36(8): 1310-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25026939

RESUMO

BACKGROUND: Mature podocytes are in cell cycle arrest and their inability to proliferate successfully is a consequence of negative cell-cycle regulators' expression, such as p57. Phosphorylated smad2/smad3 (pSmad2/3) is an intracellular heteromeric mediator of transforming growth factor beta (TGF-ß) signals and, together with co-activators such as P300, regulates gene transcription, including cell cycle regulator proteins. METHODS: In order to investigate Smad pathway activation and podocyte cell cycle regulation in glomerular injury, we studied the glomerular immunohistochemical expression of p57, pSmad2/3 and P300 in samples from 67 patients with various types of glomerulonephritis (GN) and 10 normal kidney tissue specimens. RESULTS: pSmad2/3 and p300 expression were found significantly increased in all glomerular cell types in both proliferative and nonproliferative GN, while a significant reduction in p57-positive podocytes was observed when compared to controls. Staining for p57 was found to inversely correlate to pSmad2/3 suggesting that glomerular Smad pathway activation is related to down-regulation of p57 expression in proliferative glomerulonephritis. To our knowledge, this is the first study that indicates a relation between the TGF-beta/Smad signalling pathway and the cell cycle regulatory protein p57 in human GN. CONCLUSION: The increased pSmad2/3 staining together with the reduced p57 expression found in biopsy specimens with intense interstitial inflammation, indicate a possible relation between interstitial inflammation, glomerular Smad pathway activation and podocyte cell-cycle deregulation.


Assuntos
Ciclo Celular/fisiologia , Glomerulonefrite/patologia , Podócitos/citologia , Proteínas Smad/fisiologia , Adulto , Feminino , Glomerulonefrite/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Transdução de Sinais , Proteínas Smad/biossíntese , Fator de Crescimento Transformador beta
5.
Histopathology ; 62(3): 472-80, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23163571

RESUMO

AIMS: To study the clinicopathological and prognostic value of cyclin D1 overexpression in patients with breast carcinoma. METHODS AND RESULTS: Immunohistochemistry was performed on paraffin-embedded tissue specimens from 290 invasive breast carcinomas to detect the proteins cyclin D1, oestrogen receptor (ER), progesterone receptor (PR), p53, c-erbB2, and topoisomerase IIα (topoIIα). Cyclin D1 staining was quantified using a computerized image analysis method. Cyclin D1 overexpression characterized smaller, ER-positive and PR-positive tumours (P = 0.017, P < 0.0001, and P < 0.0001, respectively), of a lower histological and nuclear grade (P = 0.011 and P < 0.0001, respectively), and with reduced expression of topoIIα (P = 0.001) and p53 (P < 0.001). Cyclin D1 was found to have an independent favourable impact on the overall survival of both the unselected cohort of patients (P = 0.011) and of patients with ER-negative and lymph node-positive tumours (P = 0.034 and P = 0.015, respectively). In triple-negative tumours, cyclin D1 overexpression was found to have independent favourable impacts on both overall and relapse-free survival (P = 0.002 for both). CONCLUSIONS: This is the first immunohistochemical study to dissociate the advantageous prognostic effect of cyclin D1 overexpression from its association with ER expression, and to provide evidence that cyclin D1 overexpression may be a marker of prolonged survival in patient subgroups with aggressive phenotypes.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Ciclina D1/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Ciclina D1/análise , Intervalo Livre de Doença , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Modelos de Riscos Proporcionais , Receptores de Estrogênio/biossíntese
6.
Histopathology ; 62(6): 899-907, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23551536

RESUMO

AIMS: Our purpose was to investigate, in breast carcinomas, the prognostic importance of the proteins Wnt1 and glycogen synthasekinase (GSK)-3ß, and their associations with classic clinicopathological indices. METHODS AND RESULTS: Immunohistochemistry was performed on paraffin-embedded tissue specimens from 288 invasive breast carcinomas to detect the expression of the proteins Wnt1, GSK3ß, oestrogen receptor (ER), progesterone receptor (PR), erbB2, p53, Ki67, caspase-3 and ß-catenin. Both Wnt1 and GSK3ß were detected predominantly in the cytoplasm of the invasive tumour cells and the in-situ component, while GSK3ß was also detected in the stromal fibroblasts. Wnt1 immunoreactivity in the invasive tumour cells showed an inverse association with histological grade (P = 0.002), Ki67 (P = 0.008) and p53 (P = 0.031), while its relation with ER, erbB2 and caspase-3 was found to be positive (P = 0.007, P = 0.018 and P = 0.03, respectively). Cytoplasmic Wnt1 expression was related to a favourable prognosis within the subgroup of patients with stage II disease (P = 0.032). CONCLUSIONS: Wnt1 expression in the invasive tumour cells seems to promote differentiation and apoptosis, while being related inversely to proliferation. Therefore, this suggests its participation in the primary stages of breast carcinogenesis. The latter is supported further by the immunodetection of Wnt1 in in-situ carcinomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Proteína Wnt1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Diferenciação Celular , Proliferação de Células , Feminino , Glicogênio Sintase Quinase 3 beta , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Via de Sinalização Wnt
7.
Clin Dev Immunol ; 2013: 941893, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24069045

RESUMO

OBJECTIVE: Recent studies have shown a beneficial effect of rapamycin in passive and active Heymann Nephritis (HN). However, the mechanisms underlying this beneficial effect have not been elucidated. METHODS: Passive Heymann Nephritis (PHN) was induced by a single intravenous infusion of anti-Fx1 in 12 Sprague-Dawley male rats. One week later, six of these rats were commenced on daily treatment with subcutaneous rapamycin 0.5 mgr/kg (PHN-Rapa). The remaining six rats were used as the proteinuric control group (PHN) while six more rats without PHN were given the rapamycin solvent and served as the healthy control group (HC). All rats were sacrificed at the end of the 7th week. RESULTS: Rapamycin significantly reduced proteinuria during the autologous phase of PHN. Histological lesions were markedly improved by rapamycin. Immunofluorescence revealed attenuated deposits of autologous alloantibodies in treated rats. Untreated rats showed decreased glomerular content of both nephrin and podocin whereas rapamycin restored their expression. CONCLUSIONS: Rapamycin monotherapy significantly improves proteinuria and histological lesions in experimental membranous nephropathy. This beneficial effect may be mediated by inhibition of the alloimmune response during the autologous phase of PHN and by restoration of the normal expression of the podocyte proteins nephrin and podocin.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glomerulonefrite Membranosa/genética , Glomerulonefrite Membranosa/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Proteinúria/tratamento farmacológico , Sirolimo/farmacologia , Animais , Modelos Animais de Doenças , Glomerulonefrite Membranosa/tratamento farmacológico , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Glomérulos Renais/ultraestrutura , Masculino , Ratos , Sirolimo/administração & dosagem
8.
Histopathology ; 61(4): 644-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22882128

RESUMO

AIMS: The rate of EGFR amplification in breast cancer ranges between 0% and 15%. Recent studies have focused on the amplification status of cytosine-adenine (CA) repeats in intron 1 of the gene and correlated it with increased EGFR protein. The aim of this study was to investigate, for the first time, the significance of coding exon 8 amplification of EGFR in invasive breast cancer. METHODS AND RESULTS: We investigated, by means of real-time polymerase chain reaction (PCR), the amplification status of exon 8 of the EGFR gene in 148 paraffin-embedded tissue sections, 115 with invasive breast carcinoma and 33 controls. Immunohistochemistry was utilized to detect EGFR and human epidermal growth factor receptor 2 (HER2) expression. Univariate and multivariate statistical analyses were performed for the evaluation of our results. EGFR amplification was observed in 7.8% of the patients, and EGFR was immunodetected in 9.6%. EGFR amplification was correlated positively with EGFR expression (P < 0.0001), HER2 expression (P = 0.023), coexpression of EGFR/HER2 (P < 0.0001) and nuclear grade (P = 0.047), and inversely with ER protein expression (P = .047). CONCLUSION: It appears that amplification of the coding sequence exon 8 exhibits similar biological behaviour to amplification of the regulatory sequence in intron 1, leading to elevated levels of EGFR protein.


Assuntos
Neoplasias da Mama/genética , Receptores ErbB/genética , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Éxons , Feminino , Amplificação de Genes , Genes erbB-1 , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Reação em Cadeia da Polimerase em Tempo Real
9.
Histopathology ; 60(7): 1125-32, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22320867

RESUMO

AIMS: STAT-1 is the first member of the family of signal transducers and activators of transcription (STATs). In breast cancer experimental models, an apoptotic and antiproliferative effect has been demonstrated. Our aim was to study the role of phosphorylated STAT-1 (pSTAT-1) in invasive breast carcinoma and its prognostic significance in premenopausal and postmenopausal patients. METHODS AND RESULTS: Immunohistochemistry was performed in 165 patients in order to detect the expression of pSTAT-1 and its correlation with oestrogen receptor (ER), progesterone receptor (PR), caspase-3, and pAkt. pSTAT-1 was immunodetected in the cytoplasm of the malignant cells (11.6%). In premenopausal patients, cytoplasmic pSTAT-1 was positively correlated with stage (P = 0.014), ER (P = 0.008), caspase-3 (P = 0.029), and pAkt (P = 0.045). Univariate analysis showed that cytoplasmic pSTAT-1 was associated with poor overall survival (P = 0.042) and the phenotype of pSTAT-1/ER or PR coexpression with shorter disease-free survival (P = 0.012). In contrast, in postmenopausal patients, no association with clinicopathological parameters and survival was observed, except for the relationship of pSTAT-1/ER or PR coexpression with longer disease-free survival (P = 0.034). CONCLUSIONS: This is the first study examining the role of pSTAT-1 in premenopausal and postmenopausal women with invasive breast cancer. Our results suggest that pSTAT-1 is related to tumour progression in premenopausal patients through the advanced stage and worse survival.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fator de Transcrição STAT1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Caspase 3/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Fosforilação , Pós-Menopausa , Pré-Menopausa , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Fator de Transcrição STAT1/química
10.
Nephrol Dial Transplant ; 27(8): 3141-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22290989

RESUMO

BACKGROUND: In the normal kidney, rapamycin is considered to be non-nephrotoxic. In the present study, we investigated whether rapamycin is indeed non-nephrotoxic by examining the ultrastructural and molecular alterations of podocytes in healthy mice. METHODS: Balb/c mice were given three different intraperitoneal doses of rapamycin for 1 week (dose model)-low-dose group: 1 mg/kg/day, intermediate-dose (ID) group: 1.5 mg/kg/day and high-dose (HD) group: 3 mg/kg/day; four mice in each group. An ID of rapamycin was also given for three different periods (time model): 1, 4 and 8 weeks; four mice were in each group. Mice treated with dimethyl sulphoxide served as controls. Body weight was measured weekly. Renal function was assessed by serum creatinine at the time of sacrifice. For estimation of albuminuria, 24-h urine collections were performed before treatment and weekly thereafter. Glomerular content of nephrin, podocin, Akt and Ser473-phospho-Akt was estimated by western blot and immunofluorescence. Nephrin and podocin messenger RNA (mRNA) were measured by real-time polymerase chain reaction. Mean podocyte foot process width (FPW) was measured by electron microscopy. RESULTS: Urine albumin levels increased in the HD and 4-week groups. Renal function was modestly deteriorated in the HD group. The mean FPW increased in a dose-dependant manner at Week 1, further deteriorated at Week 4 and finally improved at Week 8. Nephrin and podocin mRNA levels showed a significant decrease at Week 1 and were restored at Week 4 and 8. Nephrin and podocin protein levels were reduced at Week 4 and recovered at Week 8. Ser473-phospho-Akt significantly increased in all rapamycin-treated groups. CONCLUSIONS: Rapamycin induced significant ultrastructural and molecular alterations in podocytes in association with albuminuria. These alterations happened early during treatment and they tended to improve over an 8-week treatment period.


Assuntos
Podócitos/efeitos dos fármacos , Sirolimo/toxicidade , Animais , Creatinina/sangue , Ativação Enzimática/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Imunossupressores/administração & dosagem , Imunossupressores/toxicidade , Peptídeos e Proteínas de Sinalização Intracelular/genética , Transplante de Rim , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Podócitos/metabolismo , Podócitos/ultraestrutura , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirolimo/administração & dosagem
11.
Diagnostics (Basel) ; 12(2)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35204461

RESUMO

Ongoing research continues to elucidate the complex role of ephrin receptors (EPHs) and their ligands (ephrins) in breast cancer pathogenesis, with their varying expression patterns implied to have an important impact on patients' outcome. The current study aims to investigate the clinical significance of EPHA2, EPHA4, and EPHA7 expression in triple-negative breast cancer (TNBC) cases. EPHA2, EPHA4, and EPHA7 protein expression was assessed immunohistochemically on formalin-fixed and paraffin-embedded (FFPE) TNBC tissue sections from 52 TNBC patients and correlated with key clinicopathologic parameters and patients' survival data (overall survival (OS); disease-free survival (DFS)). EPHA2, EPHA4, and EPHA7 expression was further examined in TNBC cell lines. EPHA2 overexpression was observed in 26 (50%) of the TNBC cases, who exhibited a shorter OS and DFS than their low-expression counterparts, with EPHA2 representing an independent prognostic factor for OS and DFS (p = 0.0041 and p = 0.0232, respectively). EPHA4 overexpression was associated with lymph node metastasis in TNBC patients (p = 0.0546). Alterations in EPHA2, EPHA4, and EPHA7 expression levels were also noted in the examined TNBC cell lines. Our study stresses that EPHA2 expression constitutes a potential prognostic factor for TNBC patients. Given the limited treatment options and poorer outcome that accompany the TNBC subtype, EPHA2 could also pose as a target for novel, more personalized, and effective therapeutic approaches for those patients.

12.
Nephrol Dial Transplant ; 26(2): 498-508, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20709738

RESUMO

BACKGROUND: The mammalian target of rapamycin (mTOR) inhibitor, rapamycin, has been shown to inhibit the progression of murine lupus nephritis by virtue of its potent immunosuppressive properties. The phosphoinositol-3-kinase (PI3K)/Akt pathway is a major upstream activator of mTOR and has been implicated in the propagation of cancer and autoimmunity. However, the activation status of the PI3K/Akt/mTOR pathway in lupus nephritis has not been studied so far. METHODS: In NZBW/F1 female mice, we examined the glomerular expression of Akt and mTOR by immunofluorescence and western blot. We also searched for specific phosphorylations of these kinases known to ensue during activation of the PI3K/Akt/mTOR pathway. In parallel, we examined the therapeutic role of rapamycin either before or after the development of overt lupus nephritis. RESULTS: We found that in untreated mice, as opposed to healthy controls, Akt and mTOR were over-expressed and phosphorylated at key activating residues. Rapamycin prolonged survival, maintained normal renal function, normalized proteinuria, restored nephrin and podocin levels, reduced anti-dsDNA titres, ameliorated histological lesions, and reduced Akt and mTOR glomerular expression activation. CONCLUSIONS: These results suggest that: (i) the PI3K/Akt/mTOR pathway is upregulated in murine lupus nephritis, thus justifying treatment with rapamycin; (ii) rapamycin not only blocks mTOR but also negatively regulates the PI3K/Akt/mTOR pathway; and (iii) rapamycin is an effective treatment of murine lupus nephritis. Examination of the PI3K/Akt/mTOR pathway may offer new insights into the pathogenesis of lupus nephritis in humans and may lead to more individualized and less toxic treatment.


Assuntos
Imunossupressores/farmacologia , Nefrite Lúpica/metabolismo , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Feminino , Camundongos , Transdução de Sinais , Regulação para Cima
13.
Diagnostics (Basel) ; 11(11)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34829293

RESUMO

Pregnane X Receptor (PXR) is involved in human cancer, either by directly affecting carcinogenesis or by inducing drug-drug interactions and chemotherapy resistance. The clinical significance of PXR expression in invasive breast carcinoma was evaluated in the present study. PXR protein expression was assessed immunohistochemically on formalin fixed paraffin-embedded breast invasive carcinoma tissue sections, obtained from 148 patients, and was correlated with clinicopathological parameters, molecular phenotypes, tumor cells' proliferative capacity, and overall disease-free patients' survival. Additionally, the expression of PXR was examined on human breast carcinoma cell lines of different histological grade, hormonal status, and metastatic potential. PXR positivity was noted in 79 (53.4%) and high PXR expression in 48 (32.4%), out of 148 breast carcinoma cases. High PXR expression was positively associated with nuclear grade (p = 0.0112) and histological grade of differentiation (p = 0.0305), as well as with tumor cells' proliferative capacity (p = 0.0051), and negatively with luminal A subtype (p = 0.0295). Associations between high PXR expression, estrogen, and progesterone receptor negative status were also recorded (p = 0.0314 and p = 0.0208, respectively). High PXR expression was associated with shorter overall patients' survival times (log-rank test, p = 0.0009). In multivariate analysis, high PXR expression was identified as an independent prognostic factor of overall patients' survival (Cox-regression analysis, p = 0.0082). PXR expression alterations were also noted in breast cancer cell lines of different hormonal status. The present data supported evidence that PXR was related to a more aggressive invasive breast carcinoma phenotype, being a strong and independent poor prognosticator.

14.
Histopathology ; 56(7): 876-82, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20636791

RESUMO

AIMS: Loss of phosphatase and tensin homologue (PTEN) leads to activation of several kinases, including mammalian target of rapamycin (mTOR), which promotes cell cycle progression. The aim was to study the expression of PTEN and phosphorylated (p)-mTOR in familial and sporadic invasive breast carcinomas and their relation to clinicopathological features, molecular indices (Wnt1) and patients' survival. METHODS AND RESULTS: PTEN and p-mTOR were detected immunohistochemically in 215 sections of invasive breast carcinomas (112 with a familial history of breast cancer). Image analysis was used and univariate and multivariate analyses employed for statistical evaluation of results. PTEN was detected in the nucleus (73.5%) and p-mTOR in the cytoplasm (44.2%) of cancer cells. Loss of PTEN protein was more frequently detected in women with a familial history of breast cancer (72%) (P < 0.0001), while its expression was negatively correlated with Wnt1, in total (P = 0.049). p-mTOR showed a positive association with lymph node status (P = 0.010) and was found to have a negative impact on patients' overall survival (P = 0.016). CONCLUSIONS: Loss of PTEN protein expression appears to occur more frequently in women with a family history of breast cancer, whereas activation of mTOR protein seems to be related to a more aggressive phenotype.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma/patologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Fosforilação , Modelos de Riscos Proporcionais , Serina-Treonina Quinases TOR
15.
Nephrol Dial Transplant ; 25(6): 2020-3, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20133281

RESUMO

Light-chain deposition disease (LCDD) is caused by an underlying clonal plasma cell dyscrasia in which monoclonal immunoglobulin light chains (LCs) are deposited in tissues, resulting in varying degrees of organ dysfunction. Autologous stem cell transplantation (ASCT) has been reported to stabilize renal function in patients with LCDD, but currently, no evidence of histopathologic resolution of LC deposition after ASCT exists. We present a patient, with severe renal dysfunction due to LCDD, who was treated with high-dose melphalan and ASCT that resulted in a significant and extended period of improved renal function. Four years after the initial improvement, the patient developed nephrotic range proteinuria, without any evidence of relapse of the plasma cell dyscrasia. At that time, a repeat renal biopsy showed complete resolution of LC depositions and development of extensive glomerulosclerosis, thus explaining proteinuria. To the best of our knowledge, this is the first report of a biopsy-proven resolution of renal LCDD following ASCT. A timely application of ASCT should be considered in LCDD to prevent deterioration of renal function in the long run.


Assuntos
Cadeias Leves de Imunoglobulina/metabolismo , Nefropatias/imunologia , Nefropatias/terapia , Paraproteinemias/imunologia , Paraproteinemias/terapia , Transplante de Células-Tronco , Biópsia , Feminino , Humanos , Rim/imunologia , Rim/patologia , Rim/fisiopatologia , Nefropatias/patologia , Nefropatias/fisiopatologia , Pessoa de Meia-Idade , Paraproteinemias/patologia , Paraproteinemias/fisiopatologia , Transplante Autólogo
16.
Ren Fail ; 32(8): 1000-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20722569

RESUMO

We present a case of interstitial nephritis and nephrogenic diabetes insipidus (NDI) in a patient treated with pemetrexed (500 mg/m(2)) for non-small cell lung cancer. Renal impairment and diabetes insipidus appeared after the first treatment cycle while he totally received four cycles of chemotherapy. There was not any significant myelosuppression and the patient was on regular supplementation with folic acid and vitamin B(12). He was not on any other medications and he did not receive any nephrotoxic agents. Kidney biopsy showed acute tubular necrosis together with interstitial inflammatory infiltrate of mononuclear cells and interstitial fibrosis occupying 25% of the cortex. There was not any improvement of renal function after a 2-week trial of oral prednisone. In the present case report, we review the literature for pemetrexed-induced renal toxicity and the possible mechanisms involved.


Assuntos
Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Diabetes Insípido Nefrogênico/diagnóstico , Glutamatos/efeitos adversos , Guanina/análogos & derivados , Nefrite Intersticial/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/patologia , Diabetes Insípido Nefrogênico/terapia , Guanina/efeitos adversos , Humanos , Neoplasias Pulmonares , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/diagnóstico , Nefrite Intersticial/terapia , Pemetrexede
17.
Ren Fail ; 32(2): 243-53, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20199187

RESUMO

BACKGROUND: Sp1 is a ubiquitous transcription factor that mediates the fibrogenic factor transforming growth factor beta (TGF-beta) signals through cooperation with Smad proteins. The transcriptional coactivator p300 is also suggested to play a role in Smad signal transduction. METHODS: We investigated the immunohistochemical expression of Sp1 as well as the expression of pSmad2/3 and the coactivator p300 in 157 renal biopsy specimens from patients with various types of glomerulonephritis (GN). Correlations between immunohistochemical, clinical, and histologic parameters were performed. RESULTS: Sp1 exhibited an increased glomerular and proximal tubular expression in all forms of GN compared to controls. The proximal tubular expression of Sp1 was significantly increased in proliferative GNs (p = 0.025), whereas in secondary GNs, there was a significant increase in the molecule's glomerular expression (p = 0.008). Sp1 correlated positively with pSmad2/3 and p300 expression in proximal tubules (r = 0.241, p = 0.018 and r = 0.244, p = 0.014, respectively), while in proliferative GNs, its expression correlated positively with pSmad2/3 expression in glomeruli (r = 0.32, p = 0.028). Sp1 glomerular and proximal tubular immunostaining correlated positively with serum creatinine levels (r = 0.265, p = 0.02 and r = 0.306, p = 0.006, respectively), while its proximal tubular expression showed a similar correlation with interstitial fibrosis (r = 0.213, p = 0.025). Sp1 was constantly detected in hyperplastic lesions and cellular crescents (each 100%), and very often in micro adhesions (94%) and segmentally or globally sclerotic areas (each 83%). CONCLUSIONS: This study documents the upregulation of Sp1 expression in glomeruli and proximal tubules of GN specimens. Our findings suggest a possible cooperation of Sp1 with pSmad2/3 and p300 in mediating renal injury as well as a possible role for this molecule in the pathogenesis and the progression of human GN.


Assuntos
Glomerulonefrite/metabolismo , Fator de Transcrição Sp1/metabolismo , Adulto , Biópsia , Distribuição de Qui-Quadrado , Proteína p300 Associada a E1A , Feminino , Glomerulonefrite/patologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Transdução de Sinais , Proteína Smad3/metabolismo , Estatísticas não Paramétricas , Regulação para Cima
18.
Am J Kidney Dis ; 54(2): 340-4, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19303679

RESUMO

Corticosteroids and/or cyclosporine constitute the present therapeutic approach for patients with focal segmental glomerulosclerosis (FSGS). The high incidence of side effects for the former and risk of nephrotoxicity combined with the high relapse rate after discontinuation for the latter render their use problematic. Results concerning the role of rapamycin in the treatment of patients with FSGS are conflicting. We describe results for 3 patients treated with a combination of low-dose steroids and rapamycin for FSGS, focusing on the importance of maintaining low drug (rapamycin) levels by using a twice-daily regimen.


Assuntos
Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Metilprednisolona/uso terapêutico , Sirolimo/uso terapêutico , Adulto , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Breast Cancer Res ; 10(3): R49, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18522728

RESUMO

INTRODUCTION: Epidermal growth factor receptor (EGFR) is involved in regulating cell growth in breast carcinomas. Its activated form, phosphorylated EGFR (pEGFR), is correlated with poor prognosis in lung cancer, but it has not yet been fully investigated in breast cancer. The aim of this study was to investigate the expressions of EGFR and pEGFR and their correlation with overall and disease-free survival, clinicopathological parameters and biological markers of invasion and angiogenesis (phosphorylated Akt [pAkt], urokinase plasminogen activator receptor [uPAR], matrix metalloproteinase [MMP]-14, vascular endothelial growth factor receptor [VEGFR]-1/Flt-1). METHODS: A three-step immunohistochemical method was applied to paraffin-embedded sections from 154 patients with invasive breast carcinoma in order to detect expressions of the proteins EGFR, pEGFR, oestrogen receptor, progesterone receptor, c-erbB-2, pAkt, VEGFR-1/Flt-1, MMP-14 and uPAR. The results were evaluated statistically using the chi2 test. Overall and disease-free survival distribution curves were assessed using the Kaplan-Meier test and log-rank statistics, followed by Cox proportional hazards regression model. RESULTS: EGFR and pEGFR proteins were immunodetected in the membrane of the malignant cells (11.3% and 35.7%, respectively). EGFR expression was positively correlated with nuclear grade (P = 0.001) and negatively correlated with the hormonal receptor oestrogen receptor (P = 0.005). pEGFR was positively related to the Akt pathway (P = 0.008) and appeared to participate in invasion and metastasis (uPAR, P = 0.049; MMP-14, P = 0.025; VEGFR-1/Flt-1, P = 0.016). Univariate analysis showed that the EGFR/pEGFR phenotype was associated with poor overall survival (P = 0.019), a finding further supported by multivariate analysis (P = 0.013). CONCLUSION: These data provide evidence that pEGFR expression is related to angiogenesis (via VEGFR-1/Flt-1, MMP-14 and pAkt pathways) and invasiveness (via uPAR, MMP-14 and pAkt pathways) and that the EGFR/pEGFR phenotype is associated with poor patient survival in invasive breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptores ErbB/biossíntese , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Menopausa , Pessoa de Meia-Idade , Modelos Biológicos , Invasividade Neoplásica , Neovascularização Patológica , Fosforilação
20.
Antimicrob Agents Chemother ; 52(7): 2335-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18411320

RESUMO

A biodegradable system of poly-D,L-dilactide releasing ciprofloxacin was assessed in a Pseudomonas aeruginosa osteomyelitis model after inoculation of the test pathogen into the left tibia of 76 New Zealand White rabbits; 31 were controls (group A), and 45 were implanted with the polymer at the infection site (group B). The rabbits were killed on a weekly basis, and cancellous bone was harvested for histopathology and for estimation of bacterial growth and the concentrations of ciprofloxacin. Tibial X ray was performed immediately before the animals were killed. The total number of fistulas with purulent discharge that developed after inoculation of the pathogen was counted, and fistulas with purulent discharge were found in 16 animals in group A (51.6%) and 3 animals in group B (6.7%) (P < 0.0001). The animals in group A had a profound loss of body weight compared to the animals in group B. The main radiological finding was the presence of sequestra in 25 animals (80.6%) in group A and 6 animals in group B (13.3%) (P < 0.0001). The bacterial load in group B was significantly reduced compared to that in group A, possibly due to the prolonged local antibiotic release at concentrations exceeding even 80 times the MIC for the test pathogen. The histology of animals killed after week 49 revealed a mild inflammatory reaction accompanied by diffuse fibrosis and new bone formation in group A animals and the presence of small polymer particles in group B animals. It is concluded that the system described achieved eradication of the pathogen, accompanied by clinical and radiologically confirmed benefits, so this treatment may be a candidate for the management of difficult orthopedic infections.


Assuntos
Antibacterianos/administração & dosagem , Ciprofloxacina/administração & dosagem , Osteomielite/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Implantes Absorvíveis , Animais , Antibacterianos/farmacocinética , Ciprofloxacina/farmacocinética , Modelos Animais de Doenças , Implantes de Medicamento , Humanos , Masculino , Osteomielite/metabolismo , Osteomielite/microbiologia , Poliésteres , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Coelhos , Tíbia
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