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1.
Pathology ; 54(1): 49-54, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34955242

RESUMO

Previous reports have shown that quantification of high tumour grade is of prognostic significance for patients with prostate cancer. In particular, percent Gleason pattern 4 (GP4) has been shown to predict outcome in several studies, although conflicting results have also been reported. A major issue with these studies is that they rely on surrogate markers of outcome rather than patient survival. We have investigated the prognostic predictive value of quantifying GP4 in a series of prostatic biopsies containing Gleason score 3+4=7 and 4+3=7 tumours. It was found that the length of GP4 tumour determined from the measurement of all biopsy cores from a single patient, percent GP4 present and absolute GP4 were all significantly associated with distant progression of tumour, all-cause mortality and cancer-specific mortality over a 10-year follow-up period. Assessment of the relative prognostic significance showed that these parameters outperformed division of cases according to Gleason score (3+4=7 versus 4+3=7). International Society of Urological Pathology (ISUP) Grade Groups currently divide these tumours, according to Gleason grading guidelines, into grade 2 (3+4=7) and grade 3 (4+3=7). Our results indicate that this simple classification results in the loss of important prognostic information. In view of this we would recommend that ISUP Grade Groups 2 and 3 be amalgamated as grade 2 tumour with the percentage of GP4 carcinoma being appended to the final grade, e.g., 3+4=7 carcinoma with 40% pattern 4 tumour would be classified as ISUP Grade Group 2 (40%).


Assuntos
Adenocarcinoma/patologia , Prognóstico , Neoplasias da Próstata/patologia , Biópsia com Agulha de Grande Calibre , Humanos , Masculino , Gradação de Tumores/métodos , Próstata/patologia , Prostatectomia , Estudos Retrospectivos
2.
Oncogenesis ; 6(5): e335, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28504690

RESUMO

Despite advances in early diagnosis and the development of molecularly targeted therapy, curative treatment of colon cancer once it has metastasized is yet to be accomplished. This is closely associated with deregulated CRC cell proliferation and resistance to apoptosis. Here we reveal that upregulation of microRNA-645 (miR-645) through DNA copy number gain is responsible for enhanced proliferation and resistance to apoptosis in colon cancer. MiR-645 was upregulated in most colon cancer tissues related to adjacent normal mucosa. This appeared to be associated with amplification of a section of chromosome 20q13.13, where miR-645 is located. Inhibition of miR-645 reduced proliferation and enhanced sensitivity to apoptosis triggered by the chemotherapeutic drugs 5-fluorouracil and cisplatin in CRC cells, and retarded colon cancer xenograft growth. Conversely, overexpression of miR-645 in normal colon epithelial cells enhanced proliferation and triggered anchorage-independent cell growth. Although SRY-related HMG-box 30 (SOX30) was identified as a miR-645 target, its expression was only partially affected by miR-645, suggesting that miR-645 is a fine-tuning mechanism of SOX30 expression. Moreover, overexpression of SOX30 only moderately inhibited promotion of CRC cell proliferation by miR-645, indicating that miR-645 may have more targets that contribute to its pro-proliferation effect in colon cancer. Together, this study reveals that miR-645 can regulate oncogenesis in colon cancer with SOX30 being one of its targets.

3.
Oncogene ; 35(23): 3049-61, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-26411369

RESUMO

Inositol polyphosphate 4-phosphatase type II (INPP4B) negatively regulates phosphatidylinositol 3-kinase signaling and is a tumor suppressor in some types of cancers. However, we have found that it is frequently upregulated in human colon cancer cells. Here we show that silencing of INPP4B blocks activation of Akt and serum- and glucocorticoid-regulated kinase 3 (SGK3), inhibits colon cancer cell proliferation and retards colon cancer xenograft growth. Conversely, overexpression of INPP4B increases proliferation and triggers anchorage-independent growth of normal colon epithelial cells. Moreover, we demonstrate that the effect of INPP4B on Akt and SGK3 is associated with inactivation of phosphate and tensin homolog through its protein phosphatase activity and that the increase in INPP4B is due to Ets-1-mediated transcriptional upregulation in colon cancer cells. Collectively, these results suggest that INPP4B may function as an oncogenic driver in colon cancer, with potential implications for targeting INPP4B as a novel approach to treat this disease.


Assuntos
Neoplasias do Colo/genética , Monoéster Fosfórico Hidrolases/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Imuno-Histoquímica , Monoéster Fosfórico Hidrolases/metabolismo
4.
Oncogene ; 28(18): 1960-70, 2009 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-19330021

RESUMO

The Trk family of neurotrophin tyrosine kinase receptors is emerging as an important player in carcinogenic progression in non-neuronal tissues. Here, we show that breast tumors present high levels of TrkA and phospho-TrkA compared to normal breast tissues. To further evaluate the precise functions of TrkA overexpression in breast cancer development, we have performed a series of biological tests using breast cancer cells that stably overexpress TrkA. We show that (1) TrkA overexpression promoted cell growth, migration and invasion in vitro; (2) overexpression of TrkA per se conferred constitutive activation of its tyrosine kinase activity; (3) signal pathways including PI3K-Akt and ERK/p38 MAP kinases were activated by TrkA overexpression and were required for the maintenance of a more aggressive cellular phenotype; and (4) TrkA overexpression enhanced tumor growth, angiogenesis and metastasis of xenografted breast cancer cells in immunodeficient mice. Moreover, recovered metastatic cells from the lungs exhibited enhanced anoikis resistance that was abolished by the pharmacological inhibitor K252a, suggesting that TrkA-promoted breast tumor metastasis could be mediated at least in part by enhancing anoikis resistance. Together, these results provide the first direct evidence that TrkA overexpression enhances the tumorigenic properties of breast cancer cells and point to TrkA as a potential target in breast cancer therapy.


Assuntos
Neoplasias da Mama/genética , Proliferação de Células , Receptor trkA/genética , Animais , Anoikis/fisiologia , Biópsia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Linhagem Celular Tumoral , Movimento Celular , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Feminino , Proteínas de Fluorescência Verde/metabolismo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos SCID , Invasividade Neoplásica , Metástase Neoplásica , Neovascularização Patológica , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
5.
Oncogene ; 27(10): 1472-7, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-17767197

RESUMO

Tamoxifen (TAM), is widely used as a single agent in adjuvant treatment of breast cancer. Here, we investigated the effects of TAM in combination with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in estrogen receptor-alpha (ER-alpha)-positive and -negative breast cancer cells. We showed that cotreatment with TAM and TRAIL synergistically induced apoptosis regardless of ER-alpha status. By contrast, cotreatment did not affect the viability of normal breast epithelial cells. Cotreatment with TAM and TRAIL in breast cancer cells decreased the levels of antiapoptotic proteins including FLIPs and Bcl-2, and enhanced the levels of proapoptotic proteins such as FADD, caspase 8, tBid, Bax and caspase 9. Furthermore, cotreatment-induced apoptosis was efficiently reduced by FADD- or Bid-siRNA, indicating the implication of both extrinsic and intrinsic pathways in synergistic apoptosis induction. Importantly, cotreatment totally arrested tumor growth in an ER-alpha-negative MDA-MB-231 tumor xenograft model. The abrogation of tumor growth correlated with enhanced apoptosis in tumor tissues. Our findings raise the possibility to use TAM in combination with TRAIL for breast cancers, regardless of ER-alpha status.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Proteínas Reguladoras de Apoptose/fisiologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Tamoxifeno/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Inibidores do Crescimento/uso terapêutico , Humanos , Ligante Indutor de Apoptose Relacionado a TNF/uso terapêutico
6.
Pathol Biol (Paris) ; 54(4): 194-8, 2006 May.
Artigo em Francês | MEDLINE | ID: mdl-16632259

RESUMO

From differential analysis for the identification of biomarkers, to functional analysis for the evidencing of new therapeutic targets, proteomics brings new comprehensive information for a better understanding of the molecular basis of oncology and new perspectives for the clinic. However the major limitation of proteomic investigations and more generally of post-genomic approaches remains the molecular and cellular complexity of biological systems. This will be illustrated with the case of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteínas de Neoplasias/efeitos dos fármacos , Proteômica , Antineoplásicos/uso terapêutico , Feminino , Humanos
7.
Exp Cell Res ; 298(2): 560-73, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15265702

RESUMO

Inhibitors of histone deacetylase (HDAC) are considered as potential anticancer agents. We have previously demonstrated that an inhibitor of HDAC, sodium butyrate (NaB), induces apoptosis of breast cancer cells in a P53-independent and P21(waf1)-dependent manner. In this study, we showed that tumor necrosis factor-alpha (TNF-alpha), TNF-related apoptosis-inducing ligand (TRAIL), and anti-Fas agonist antibody potentiated NaB-induced growth inhibition through synergistic induction of apoptosis in breast cancer cell lines (MCF-7, T47-D, and BT-20). In MCF-7 cells, NaB increased the expression of death receptors; NaB alone or in combination with TNF-alpha, TRAIL, and anti-Fas agonist antibody increased the levels of Bid, tBid, and that of cytosolic cytochrome c. Synergistic induction of apoptosis was strongly inhibited by dominant-negative Fas-associated death domain (FADD) and inhibitors of caspases-8 and -9, indicating that potentiation of apoptosis involved key elements of death receptors' signaling pathways. Moreover, cotreatment of NaB and ligands of death receptors up-regulated the levels of P21(waf1) and that of proliferating cell nuclear antigen (PCNA) associated with P21(waf1). Transient transfections of p21(waf1) antisense or p21(waf1) deficient for its interaction with PCNA abolished synergistic induction of apoptosis. This suggested that potentiation of apoptosis by cotreatments required P21(waf1) and its interaction with PCNA. Since breast tumors contain rarely p21 mutations, our results may open interesting prospects in the fight against breast cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Ciclinas/efeitos dos fármacos , Receptor fas/efeitos dos fármacos , Anticorpos/farmacologia , Anticorpos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/metabolismo , Apoptose/genética , Proteínas Reguladoras de Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Butiratos/farmacologia , Butiratos/uso terapêutico , Carcinoma/genética , Carcinoma/metabolismo , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Ciclinas/metabolismo , Citocromos c/efeitos dos fármacos , Citocromos c/metabolismo , Sinergismo Farmacológico , Proteína de Domínio de Morte Associada a Fas , Feminino , Inibidores de Histona Desacetilases , Histona Desacetilases/metabolismo , Humanos , Glicoproteínas de Membrana/farmacologia , Glicoproteínas de Membrana/uso terapêutico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/uso terapêutico , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Receptor fas/imunologia , Receptor fas/metabolismo
8.
Proteomics ; 1(10): 1216-32, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11721634

RESUMO

Breast cancer is the most common form of cancer among women and the identification of markers to discriminate tumorigenic from normal cells, as well as the different stages of this pathology, is of critical importance. Two-dimensional electrophoresis has been used before for studying breast cancer, but the progressive completion of human genomic sequencing and the introduction of mass spectrometry, combined with advanced bioinformatics for protein identification, have considerably increased the possibilities for characterizing new markers and therapeutic targets. Breast cancer proteomics has already identified markers of potential clinical interest (such as the molecular chaperone 14-3-3 sigma) and technological innovations such as large scale and high throughput analysis are now driving the field. Methods in functional proteomics have also been developed to study the intracellular signaling pathways that underlie the development of breast cancer. As illustrated with fibroblast growth factor-2, a mitogen and motogen factor for breast cancer cells, proteomics is a powerful approach to identify signaling proteins and to decipher the complex signaling circuitry involved in tumor growth. Together with genomics, proteomics is well on the way to molecularly characterizing the different types of breast tumor, and thus defining new therapeutic targets for future treatment.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Exonucleases , Proteínas de Neoplasias/metabolismo , Proteoma/metabolismo , Transdução de Sinais , Proteínas 14-3-3 , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/química , Biópsia , Neoplasias da Mama/etiologia , Neoplasias da Mama/terapia , Eletroforese em Gel Bidimensional , Exorribonucleases , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/química , Proteínas/metabolismo , Proteoma/análise , Proteoma/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Bull Cancer ; 88(7): 663-70, 2001 Jul.
Artigo em Francês | MEDLINE | ID: mdl-11495819

RESUMO

The proteome, first formalized in 1995, designs all the proteins expressed by the genome of a cell, tissu, or organ at a defined time. Proteomic analysis leads to a description of the regulation of gene expression by the study of proteins and of their post-translational modifications. Proteomic analysis is based on three technologies: 1) Two-dimensional electrophoresis allowing the separation of thousands of proteins from a single mixture; 2) mass spectrometry allowing the characterization of picoquantities of polypeptides and providing data on post-translational modifications; 3) Bioinformatic which is required for the quantification of protein level and for the constitution of databases of protein expression profiles. Complementing the methods of the genomics, the use of proteomic analysis is widely spreading in the fields of fundamental biology, biomedicine and pharmacology for the identification of new biological markers and therapeutic targets.


Assuntos
Eletroforese em Gel Bidimensional/métodos , Espectrometria de Massas/métodos , Proteínas/análise , Animais , Regulação da Expressão Gênica , Humanos , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/metabolismo
10.
Cancer Res ; 61(11): 4337-40, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11389056

RESUMO

Nerve growth factor (NGF) has been shown recently to be mitogenic for human breast cancer cells. In the present study, we have assayed the expression of NGF receptors (NGFRs: TrkA and p75) mRNAs in 363 human primary breast cancers, using real-time quantitative reverse transcription-PCR. NGFRs were found in all of the tumor biopsies. TrkA and p75 were positively correlated and were respectively associated with the histoprognostic grading and the tumor type. NGFRs were both related to progesterone receptors. In univariate analyses, TrkA (>upper quartile) was associated with longer overall survival. Histoprognostic grading, tumor size, node involvement, and steroid receptors were also prognostic factors. In Cox multivariate analyses, TrkA was not a prognostic parameter. This study demonstrates the expression of NGFRs in breast cancer and points out that patients with high levels of TrkA have a more favorable overall survival prognosis.


Assuntos
Neoplasias da Mama/metabolismo , Receptor trkA/biossíntese , Receptores de Fator de Crescimento Neural/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor de Fator de Crescimento Neural , Receptor trkA/genética , Receptores de Fator de Crescimento Neural/genética
11.
J Biol Chem ; 276(21): 17864-70, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11359788

RESUMO

We show here that the neurotrophin nerve growth factor (NGF), which has been shown to be a mitogen for breast cancer cells, also stimulates cell survival through a distinct signaling pathway. Breast cancer cell lines (MCF-7, T47-D, BT-20, and MDA-MB-231) were found to express both types of NGF receptors: p140(trkA) and p75(NTR). The two other tyrosine kinase receptors for neurotrophins, TrkB and TrkC, were not expressed. The mitogenic effect of NGF on breast cancer cells required the tyrosine kinase activity of p140(trkA) as well as the mitogen-activated protein kinase (MAPK) cascade, but was independent of p75(NTR). In contrast, the anti-apoptotic effect of NGF (studied using the ceramide analogue C2) required p75(NTR) as well as the activation of the transcription factor NF-kB, but neither p140(trkA) nor MAPK was necessary. Other neurotrophins (BDNF, NT-3, NT-4/5) also induced cell survival, although not proliferation, emphasizing the importance of p75(NTR) in NGF-mediated survival. Both the pharmacological NF-kappaB inhibitor SN50, and cell transfection with IkBm, resulted in a diminution of NGF anti-apoptotic effect. These data show that two distinct signaling pathways are required for NGF activity and confirm the roles played by p75(NTR) and NF-kappaB in the activation of the survival pathway in breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fator de Crescimento Neural/farmacologia , Transdução de Sinais/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , NF-kappa B/metabolismo , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/metabolismo , Células Tumorais Cultivadas
12.
Cancer Res ; 61(1): 76-80, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11196201

RESUMO

The class of molecular chaperones known as 14-3-3 is involved in the control of cellular growth by virtue of its apparent regulation of various signaling pathways, including the Raf/mitogen-activated protein kinase pathway. In breast cancer cells, the sigma form of 14-3-3 has been shown to interact with cyclin-dependent kinases and to control the rate of entry into mitosis. To test for a direct role for 14-3-3 in breast epithelial cell neoplasia, we have quantitated 14-3-3 protein levels using a proteomic approach based on two-dimensional electrophoresis and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF). We show here that 14-3-3sigma protein is strongly down-regulated in the prototypic breast cancer cell lines MCF-7 and MDA-MB-231 and in primary breast carcinomas as compared with normal breast epithelial cells. In contrast, levels of the alpha, beta, delta, or zeta isoforms of 14-3-3 were the same in both normal and transformed cells. The data support the idea that 14-3-3sigma is involved in the neoplastic transition of breast epithelial cells by virtue of its role as a tumor suppressor; as such, it may constitute a robust marker with clinical efficacy for this pathology.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias da Mama/metabolismo , Exonucleases , Proteínas de Neoplasias , Proteínas 14-3-3 , Autorradiografia , Biomarcadores Tumorais/genética , Mama/metabolismo , Neoplasias da Mama/genética , Regulação para Baixo , Eletroforese em Gel Bidimensional , Células Epiteliais/metabolismo , Exorribonucleases , Regulação Neoplásica da Expressão Gênica , Humanos , Biossíntese de Proteínas , Isoformas de Proteínas , Proteínas/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Tumorais Cultivadas
13.
Exp Cell Res ; 262(1): 59-68, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11120605

RESUMO

Fibroblast growth factor-2 (FGF-2) is a potent regulator of breast cancer cell growth through stimulation of tyrosine kinase receptors and activation of the mitogen-activated protein kinase cascade. In the present study, we have investigated changes in protein synthesis induced by FGF-2 stimulation of the prototypic human breast cancer cell line MCF-7. Using high-resolution two-dimensional electrophoresis of (35)S amino acid metabolically labeled proteins and computerized analysis of 2D autoradiograms, we found that four proteins were up-regulated within the first 12 h of FGF-2 stimulation. Mass spectrometry analysis (MALDI-TOF and MS-MS) of tryptic fragments and database searches allowed the identification of these FGF-2-regulated proteins as the heat shock proteins HSP90 and HSP70, the proliferating cell nuclear antigen (PCNA), and the transcriptionaly controlled tumor protein (TCTP). We then analyzed the distribution of these proteins in various cancerous and normal breast epithelial cells. Interestingly, the four FGF-2-regulated proteins were found to be constitutively up-regulated in ras-transfected MCF-7 cells, indicating their relevance to the up-regulation of cellular proliferation. Moreover, HSP90 and PCNA were found at higher levels in cancerous cells than in normal cells. The role of HSP90 was further investigated using the specific inhibitor geldanamycin. We showed that the functionality of HSP90 is strictly required in order to obtain FGF-2 mitogenic stimulation in MCF-7 cells, indicating the crucial role played by this molecular chaperone in the control of breast cancer cell growth. Finally, these results show that proteomic analysis is a valuable method for identifying potential markers or therapeutic targets related to cancer growth.


Assuntos
Biomarcadores Tumorais , Proteínas de Ligação ao Cálcio/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteoma/metabolismo , Neoplasias da Mama , Divisão Celular , Eletroforese em Gel Bidimensional/métodos , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Células Tumorais Cultivadas , Proteína Tumoral 1 Controlada por Tradução
14.
Mol Cell Biol Res Commun ; 3(6): 338-44, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11032755

RESUMO

Cancer development depends not only on the nature of the tumor cells themselves but also on the regulatory effects of various normal cells. The present study was performed to better understand the mechanism by which normal breast epithelial cells (NBEC) can control the growth of MCF-7 breast cancer cells. When MCF-7 cells were treated with NBEC conditioned medium, cell growth was inhibited in a concentration-dependent manner. This inhibition was due to an induction of apoptosis without any change in cell cycle progression. The induction of apoptosis was correlated with increased levels of p53, p21(waf1) and decreased levels of bcl-2. Transient transfections of MCF-7 cells with two p53 cDNA constructs demonstrated the induction of apoptosis was mediated by endogenous p53. Taken together, our results indicate that NBEC inhibit the growth of MCF-7 breast cancer cells by inducing apoptosis in them via endogenous p53.


Assuntos
Apoptose , Neoplasias da Mama/patologia , Mama/metabolismo , Células Epiteliais/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Apoptose/efeitos dos fármacos , Western Blotting , Mama/citologia , Neoplasias da Mama/metabolismo , Divisão Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Mutação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transfecção , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2
16.
Cytokine Growth Factor Rev ; 11(4): 295-302, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10959077

RESUMO

FGFs are pleiotropic growth factors that control cell proliferation, migration and differentiation. However, FGF transduction studies have so far focused primarily on the mitogenic effect of this growth factor family and it has been difficult to assess if the described intracellular signaling pathways are dedicated solely to cell proliferation, or whether they are equally important for the migratory activity often seen in responsive cells. We review here papers in which the migratory effects of this growth factor family were clearly discriminated from proliferative effects. In toto, these studies suggest that cells use different signaling pathways for migration, such as Src and p38 MAP kinase, from those for proliferation, which tend to upregulate the ERKs. Which signaling pathway a cell uses for proliferation or migration appears to depend on many factors, including the structure and the quantity of available FGF trapped in the basal lamina by heparan sulfate co-factors, the disposition of cognate high affinity receptors and the general environment of the cell. Thus the density of the cell population, the state of the cell cycle, the presence of other factors or receptors will modulate the migratory response of cells to FGF.


Assuntos
Fatores de Crescimento de Fibroblastos/fisiologia , Animais , Divisão Celular , Movimento Celular , Fatores de Crescimento de Fibroblastos/química , Fatores de Crescimento de Fibroblastos/genética , Modelos Biológicos , Mutação , Receptores de Fatores de Crescimento de Fibroblastos/química , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais
17.
FEBS Lett ; 478(3): 209-15, 2000 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-10930570

RESUMO

Fibroblast growth factor-2 (FGF-2) is mitogenic for the human breast cancer cell line MCF-7; here we investigate some of the signaling pathways subserving this activity. FGF-2 stimulation of MCF-7 cells resulted in a global increase of intracellular tyrosine phosphorylation of proteins, particularly FGF receptor substrate-2, the protooncogene product Src and the mitogen-activated protein kinase (MAP kinase) cascade. A major increase in the tyrosine phosphorylation of a 30-kDa protein species was also found. This protein was identified as cyclin D2 by mass spectrometry after trypsin digestion. Immunoprecipitation of cyclin D2 and immunoblotting with anti-phosphotyrosine antibodies confirmed that the tyrosine phosphorylation of cyclin D2 was indeed induced by FGF-2 stimulation. In addition, pharmacological inhibition of Src (with herbimycin A and PP2), and of the MAP kinase cascade (with PD98059), confirmed that Src activity is required for the FGF-2-induced phosphorylation of cyclin D2 whereas MAP kinase activity is not. Thus, tyrosine phosphorylation of cyclin D2 may be a key regulatory target for FGF-2 signaling.


Assuntos
Ciclinas/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Mitógenos/farmacologia , Fosfotirosina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Western Blotting , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclina D2 , Ciclinas/química , Ativação Enzimática/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Humanos , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mitógenos/antagonistas & inibidores , Dados de Sequência Molecular , Peso Molecular , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Tumorais Cultivadas
18.
Breast Cancer Res Treat ; 60(3): 251-8, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10930113

RESUMO

Breast epithelial cells produce both mitogens and growth inhibitors which are involved in the control of mammary gland development through autocrine and paracrine pathways. While the mechanisms of action of several growth factors have been well established and related strategies proposed for breast cancer therapy, little is known concerning growth inhibitors. In this review, we present an overview of current information about major autocrine and paracrine growth inhibitors of breast epithelial cells, and we discuss their potential functions in the control of breast cancer development.


Assuntos
Comunicação Autócrina/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Substâncias de Crescimento/farmacologia , Comunicação Parácrina/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Proteoglicanas/metabolismo
19.
J Biol Chem ; 275(39): 30009-18, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-10862617

RESUMO

To explore how heparan sulfate (HS) controls the responsiveness of the breast cancer cell lines MCF-7 and MDA-MB-231 to fibroblast growth factors (FGFs), we have exposed them to HS preparations known to have specificity for FGF-1 (HS glycosaminoglycan (HSGAG A)) or FGF-2 (HSGAGB). Proliferation assays confirmed that MCF-7 cells were highly responsive to FGF-2 complexed with GAGB, whereas migration assays indicated that FGF-1/HSGAGA combinations were stimulatory for the highly invasive MDA-MB-231 cells. Quantitative polymerase chain reaction for the levels of FGF receptor (FGFR) isoforms revealed that MCF-7 cells have greater levels of FGFR1 and that MDA-MB-231 cells have greater relative levels of FGFR2. Cross-linking demonstrated that FGF-2/HSGAGB primarily activated FGFR1, which in turn up-regulated the activity of mitogen-activated protein kinase; in contrast, FGF-1/HSGAGA led to the phosphorylation of equal proportions of both FGFR1 and FGFR2, which in turn led to the up-regulation of Src and p125(FAK). MDA-MB-231 cells were particularly responsive to vitronectin substrates in the presence of FGF-1/HSGAGA, and blocking antibodies established that they used the alpha(v)beta(3) integrin to bind to it. These results suggest that the clustering of particular FGFR configurations on breast cancer cells induced by different HS chains leads to distinct phenotypic behaviors.


Assuntos
Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Heparitina Sulfato/farmacologia , Meios de Cultura Livres de Soro , Interações Medicamentosas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Fator 1 de Crescimento de Fibroblastos , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fenótipo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Receptores de Vitronectina/metabolismo
20.
Biochem Biophys Res Commun ; 267(3): 770-6, 2000 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10673367

RESUMO

The growth of the malignant human mammary MDA-MB-231 cells is stimulated by fibroblast growth factor-1 (FGF-1) but not by FGF-2. When these cells are cultured in the presence of chlorate, an inhibitor of heparan sulfate (HS) sulfation, their proliferation is stimulated by both FGF-1 and FGF-2. We analyzed the interactions of FGF-1 and FGF-2 with HS purified from the cell layer and the culture medium of control and chlorate-treated MDA-MB-231 cells. The HS from the cell layer bound FGF-1 with faster association kinetics than the HS from the culture medium, and so had a higher affinity for FGF-1. Chlorate treatment had no significant effect on the FGF-1 binding kinetics of the HS. In contrast to FGF-1, chlorate treatment of the cells significantly altered the FGF-2 binding kinetics. The HS from untreated cells possessed two binding sites for FGF-2, one with fast association kinetics (k(ass) 470,000 to 610,000 M(-1) s(-1)) and a high affinity (K(d) 46 to 70 nM) and one with slower association kinetics (k(ass) 74,000 to 100,000 M(-1) s(-1)) and a lower affinity (K(d) 290 to 400 nM). HS from chlorate-treated cells possessed just a single binding site for FGF-2 with fast association kinetics (k(ass) 270,000 to 290,000 M(-1) s(-1)) and a high affinity (K(d) 41 to 57 nM). These results show that there is a relationship between the binding kinetics of FGFs and their ability to stimulate cell growth.


Assuntos
Fator 2 de Crescimento de Fibroblastos/farmacologia , Heparitina Sulfato/metabolismo , Artefatos , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloratos/farmacologia , Feminino , Fator 1 de Crescimento de Fibroblastos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Cinética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas
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