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1.
Breast Cancer ; 30(5): 802-809, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37358721

RESUMO

INTRODUCTION: The oncoplastic conservative surgery was developed as a natural evolution of traditional surgery, attempting to improve the therapeutic and aesthetic outcomes where tumor resection could be followed by not-adequate results. Our primary aim is to evaluate how patient satisfaction and quality-of-life after conservative oncoplastic surgery, using BREAST-Q (BCT Module), change pre- and post-operatively. The secondary aim is to compare patient-reported outcome after oncoplastic or traditional conservative surgery. PATIENTS AND METHODS: We enrolled 647 patients who underwent traditional conservative surgery or oncoplastic surgery from January 2020 to December 2022. Only 232 women (35.9%) completed the BREAST-Q questionnaire on a web-based platform, at the preoperative phase and 3 months after treatment. RESULTS: The average score of "Psychosocial well-being" and "Satisfaction with Breasts" 3 months after surgery showed a statistically significant improvement, while the average score for "Physical well-being: Chest" at 3 months showed a worsening compared to the baseline. "Sexual well-being" did not show statistically significant change. A significant difference between the post-operative outcome of oncoplastic surgery and traditional surgery was observed only for Physical well-being (better for traditional surgery). CONCLUSIONS: The study showed significant improvement in patient-reported outcomes 3 months after the surgery, except for physical discomfort that increases especially after oncoplastic surgery. Furthermore, our data, as well as many others, point to the appropriateness of using OCS where there is an effective indication, while the perspective of patients cannot find significant superiority over TCS in any of the areas analyzed.


Assuntos
Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Mastectomia Segmentar/efeitos adversos , Mastectomia Segmentar/métodos , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Neoplasias da Mama/cirurgia , Mamoplastia/métodos , Satisfação Pessoal , Resultado do Tratamento
2.
Eur J Surg Oncol ; 46(6): 1034-1040, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31812290

RESUMO

One of the goals of immediate breast reconstruction (IBR) is to satisfy the patient's outcome. Recent studies therefore tended to focus on the patient's perception of the care and on the impact on quality of life using patients-reported-outcome-measures (PROMs), able to measure the health status directly without the clinician's interposition. We present a preliminary prospective study on 333 patients who underwent mastectomy with IBR in a two-year period, in a single Italian centre, using a dedicated PROMs, the BREAST-Q™, to determine the patient's satisfaction. We studied two groups of IBR: Group A (two-step with tissue-expander) and Group B (one-step: prosthesis/mesh) and conducted a pre- and post-operative comparison for each group to evaluate score-gain over time, and a group-score comparison to determine whether differences were significant between reconstruction types. Two-hundred-and-nine were actually enrolled and 132 completed all the questionnaires. The response rate was 62.8% and the compliance rate (completion of all the questionnaires) was 63.1%. In both groups all the analyzed domains worsened comparing the pre and post-operative period; the differences were statistically significant only for physical and sexual-wellbeing. In the comparison between the two groups, none of the detected differences reached the statistical significance. According to our experience, we can state that PROMs could improve the health concept redefining the variables to be monitored even if data is still insufficient to draw any definitive conclusion. PROMs can help surgeons and patients decide the most appropriate surgery for a particular patient-profile and to identify those who require further support.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia/métodos , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente/estatística & dados numéricos , Cuidados Pós-Operatórios/métodos , Medicina de Precisão/métodos , Qualidade de Vida , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários
3.
Breast Cancer Res Treat ; 178(3): 557-564, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512090

RESUMO

PURPOSE: In order to better define the breast cancer (BC) genetic risk factors in men, a germline investigation was carried out on 81 Male BC cases by screening the 24 genes involved in BC predisposition, genome stability maintenance and DNA repair mechanisms by next-generation sequencing. METHODS: Germline DNAs were tested in a custom multi-gene panel focused on all coding exons and exon-intron boundaries of 24 selected genes using two amplicon-based assays on PGM-Ion Torrent (ThermoFisher Scientific) and MiSeq (Illumina) platforms. All variants were recorded and classified by using a custom pipeline. RESULTS: Clinical pathological data and the family history of 81 Male BC cases were gathered and analysed, revealing the average age of onset to be 61.3 years old and that in 35 cases there was a family history of BC. Our genetic screening allowed us to identify a germline mutation in 22 patients (23%) in 4 genes: BRCA2, BRIP1, MUTYH and PMS2. Moreover, 12 variants of unknown clinical significance (VUS) in 9 genes (BARD1, BRCA1, BRIP1, CHEK2, ERCC1, NBN, PALB2, PMS1, RAD50) were predicted as potentially pathogenic by in silico analysis bringing the mutation detection rate up to 40%. CONCLUSION: As expected, a positive family history is a strong predictor of germline BRCA2 mutations in male BC. Understanding the potential pathogenicity of VUS represents an extremely urgent need for the management of BC risk in Male BC cases and their own families.


Assuntos
Neoplasias da Mama Masculina/genética , Reparo do DNA/genética , Predisposição Genética para Doença/genética , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Neoplasias/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama Masculina/sangue , Neoplasias da Mama Masculina/patologia , Testes Genéticos , Genoma Humano/genética , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
4.
J Transl Med ; 17(1): 187, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159827

RESUMO

BACKGROUND: Tumors develop by progression through a series of stages. Every cell of the tumor microenvironment is constantly changing in the flow of the cancer progression. It has become clear in recent years that stroma is essential for tumor maintenance and growth. Here, we aimed to give a chronological order of gene expression changes given in the dynamical framework of microinvasive breast cancer microenvironment. METHODS: RNA-seq was performed on seven microinvasive breast cancers. For each of them we microdissected seven different portions of the tumor, four related to the breast epithelium and three to the stroma. Breast epithelium was chronologically subdivided in normal breast epithelium (NBE), carcinoma in situ (CIS), emerging invasive fingers (EIF) and invasive breast cancer (IBC). For each of the breast epithelium subdivisions we collected the adjacent stroma (S): S-NBE, S-EIF and S-IBC. RESULTS: The overall differentially expressed genes (DEGs) in all the compartments were analysed and evaluated to understand the pathways involved in tumor progression. Then we analysed the DEGs of the epithelial and stromal portions in comparison with the normal portions. We observed that the stromal cells are necessary for the development and the maintenance of the tumor, especially in tumor progression. Moreover the most important genes involved in the main metabolic pathways were analysed and the communications within the different cell compartments were highlighted. CONCLUSIONS: As a future perspective, a deeply study of the identified key genes, particularly in the stromal cells, will be crucial to develop an anticancer therapy that is undergoing a conversion from a cancer cell-centric strategy to a stroma-centric strategy, more genomically stable.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Microambiente Tumoral/genética , Mama/metabolismo , Mama/patologia , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Redes e Vias Metabólicas/genética , Invasividade Neoplásica , Estadiamento de Neoplasias , Análise de Sequência de RNA , Células Estromais/patologia
5.
Breast Cancer Res Treat ; 170(3): 445-454, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29616377

RESUMO

PURPOSE: Secretory breast cancer (SBC) is one of the rarest breast cancer (BC), representing the majority of BC in childhood. Nevertheless, it elicits a lot of interest both for the peculiar morphology and the characteristic genetic features. Currently, there is no consensus on optimal treatment strategy. Therefore, it is useful to report every case in order to establish treatment algorithms. METHODS: We describe the case of a 6-year-old boy diagnosed with a SBC, with peculiar genomic and immunohistochemical features. Moreover, we carried out a review of the literature in order to analyze the present state of knowledge about this rare entity. RESULTS: To the best of our knowledge, there are only 120 cases published in literature, only 32 in males and only 2 younger than 6 years. Furthermore, this one had peculiar genomic and immunohistochemical features. Indeed, even if SBC expresses basal-cell markers, our patient had a triple-negative tumor expressing both basal and luminal cell markers. Furthermore, the boy's genomic profile revealed not only positivity for the typical SBC's translocation t(12;15), but also for a 3q28 duplication, found in his father (healthy) and paternal grandfather (with a previous BC). None were positive for BRCA mutation. This locus includes only one gene encoding for a growth factor recently linked to Early Infantile Epileptic Encephalopathy-47 and Idiopathic ventricular tachycardia. Even if the literature does not provide evidence of a pathogenic role it is not possible to exclude a cancer-predisposing activity. CONCLUSIONS: SBC is a rare type of BC, characterized by triple-negative features with an unexpectedly good prognosis. More data are needed to fully understand the behavior of this cancer and genomic profiling could be helpful in improving its diagnosis and management.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Carcinoma/diagnóstico , Carcinoma/genética , Duplicação Gênica , Biomarcadores , Neoplasias da Mama/metabolismo , Neoplasias da Mama Masculina/metabolismo , Carcinoma/metabolismo , Criança , Seguimentos , Humanos , Masculino , Carga Tumoral , Ultrassonografia
6.
Int J Cardiol ; 257: 243-246, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28918896

RESUMO

BACKGROUND: Mobilization of endothelial progenitor cells (EPCs) into circulation from bone marrow in patients with acute myocardial infarction has strong scientific evidence; less is known about EPC mobilization in patients with stable coronary artery disease (CAD). The aim of this study was to investigate the association of stable ischemic heart disease with EPC levels in tissue and blood. METHODS: Fifty-five consecutive patients admitted to a single treatment center for valve or coronary artery bypass grafting (CABG) surgeries were included in the study. Blood samples were collected in the morning before surgery and analyzed by flow-cytometry to determine peripheral EPC levels (EPC/ml). Tissue EPC (CD34+VEGFR2+) levels were assessed on a right atrial appendage segment. RESULTS: Mean age was 76±5years, 48% were men, and 53% had CAD The number of CD34+ VEGFR2+ cells in the tissue of patients with CAD was significantly higher (p<0.005) and circulating EPC showed a tendency to be reduced by approximately 20% in peripheral blood of patients with CAD when compared to those without CAD. CONCLUSION: Patients with stable CAD had higher EPC density values (EPC/mm2) and were more likely to have lower EPC blood levels when compare with normal controls.


Assuntos
Células Progenitoras Endoteliais/fisiologia , Isquemia Miocárdica/sangue , Isquemia Miocárdica/cirurgia , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/tendências , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Feminino , Citometria de Fluxo/métodos , Citometria de Fluxo/tendências , Humanos , Masculino , Isquemia Miocárdica/diagnóstico por imagem
7.
Eur Arch Paediatr Dent ; 18(2): 127-133, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28251593

RESUMO

BACKGROUND: Frontonasal dysplasia is a complex rare malformation, characterised by abnormalities involving the central portion of the face, especially the eyes, nose and forehead. It can manifest independently or associated with other abnormalities as part of some syndromes. CASE REPORT: The purpose of this case report was to describe a 5-year-old patient, diagnosed with frontonasal dysplasia. Among the abnormalities characterised with this disorder were ocular hypertelorism, broad nose tip with median notch, median facial cleft, bifid anterior skull, low set hairline, Poland's syndactyly and ankyloglossia. TREATMENT: Consisted of behavioural management, oral hygiene instruction, prophylaxis, topical fluoride application, extraction of primary teeth, composite resin restorations and sealants in pits and fissures. Preformed metal crowns were also applied to the right and left primary maxillary second molars. FOLLOW-UP: Currently, the patient is 11 years-old in the permanent dentition and therefore was referred for corrective orthodontic and periodontal treatments due to the persistence of gingival retraction of the permanent mandibular right central incisor. CONCLUSION: The treatment in this case was directed to the promotion of oral health and orthodontic corrections, which are of fundamental importance due to medical, physical and social limitations of children affected by this syndrome, hindering healing and rehabilitative treatment. Paediatric dentists should be included in multidisciplinary teams providing care to patients with special needs, improving their quality of life.


Assuntos
Anormalidades Craniofaciais/diagnóstico por imagem , Anormalidades Craniofaciais/terapia , Face/anormalidades , Aparelhos Ortodônticos , Técnica de Expansão Palatina , Pré-Escolar , Anormalidades Craniofaciais/etiologia , Face/diagnóstico por imagem , Feminino , Humanos , Radiografia Panorâmica
8.
Cancer Res ; 61(14): 5480-5, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11454695

RESUMO

Drug resistance is a prevalent problem in the treatment of neoplastic disease, and the effectiveness of many clinically useful drugs is limited by the fact that they are substrates for the efflux pump, P-glycoprotein. Because there is a need for new compounds that are effective in treating drug-resistant tumors, we tested A-204197 (4-[4-acetyl-4,5-dihydro-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazol-2-yl]-N,N-dimethylbenzeneamine), a novel oxadiazoline derivative with antiproliferative properties, on cell lines that were either sensitive or resistant to known microtubule inhibitors. Cell lines that were resistant to paclitaxel, vinblastine, or colchicine were equally sensitive to A-204197 (proliferation IC50s ranging from 36 to 48 nM) despite their expression levels of P-glycoprotein. The effect of A-204197 on cell growth was associated with cell cycle arrest in G2-M, increased phosphorylation of select G2-M checkpoint proteins, and apoptosis. In competition-binding assays, A-204197 competed with [3H]-labeled colchicine for binding to tubulin (K(i) = 0.75 microM); however, it did not compete with [3H]-labeled paclitaxel. A-204197 prevented tubulin polymerization in a dose-dependent manner (IC50 = 4.5 microM) in vitro and depolymerized microtubules in a time-dependent manner in cultured cells. These findings indicate A-204197 is a promising new tubulin-binding compound with antimitotic activity that has potential for treating neoplastic diseases with greater efficacy than currently used antimitotic agents.


Assuntos
Antineoplásicos/farmacologia , Microtúbulos/efeitos dos fármacos , Oxidiazóis/farmacologia , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Sítios de Ligação , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Divisão Celular/efeitos dos fármacos , Colchicina/metabolismo , Colchicina/farmacologia , Interações Medicamentosas , Resistência a Múltiplos Medicamentos , Fase G2/efeitos dos fármacos , Humanos , Microtúbulos/metabolismo , Mitose/efeitos dos fármacos , Oxidiazóis/metabolismo , Paclitaxel/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fatores de Tempo , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Vimblastina/farmacologia
9.
Cancer Lett ; 156(1): 63-72, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10840161

RESUMO

The p53-inducible gene 3 (PIG3) was recently identified in a screen for genes induced by p53 before the onset of apoptosis. PIG3 shares significant homology with oxidoreductases from several species. In this study, PIG3-specific antibodies were used to analyze cellular PIG3 protein levels under control and genotoxic stress conditions. PIG3 protein was localized to the cytoplasm and induced in primary, non-transformed, and transformed cell cultures after exposure to genotoxic agents. The induction of PIG3 was p53-dependent and occurred with delayed kinetics as compared with other p53 downstream targets, such as p21 and MDM2. Using a p53-inducible cell model system, in which p53-mediated growth arrest is reversible, we found that PIG3 levels were increased during p53-mediated growth arrest. Interestingly, elevated levels of PIG3 were maintained in cells that resumed cycling in the absence of ectopic p53 expression, suggesting that PIG3 is a long-lived reporter, which may be useful for detecting transient activation of p53.


Assuntos
Proteínas Nucleares , Proteínas/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Apoptose , Ciclo Celular , Divisão Celular , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Neoplasias do Colo/radioterapia , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Doxorrubicina/farmacologia , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-mdm2 , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/análise
10.
Mol Cell Biol ; 20(12): 4210-23, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10825186

RESUMO

In the present study, we investigated the role of p53 in G(2) checkpoint function by determining the mechanism by which p53 prevents premature exit from G(2) arrest after genotoxic stress. Using three cell model systems, each isogenic, we showed that either ectopic or endogenous p53 sustained a G(2) arrest activated by ionizing radiation or adriamycin. The mechanism was p21 and retinoblastoma protein (pRB) dependent and involved an initial inhibition of cyclin B1-Cdc2 activity and a secondary decrease in cyclin B1 and Cdc2 levels. Abrogation of p21 or pRB function in cells containing wild-type p53 blocked the down-regulation of cyclin B1 and Cdc2 expression and led to an accelerated exit from G(2) after genotoxic stress. Thus, similar to what occurs in p21 and p53 deficiency, pRB loss can uncouple S phase and mitosis after genotoxic stress in tumor cells. These results indicate that similar molecular mechanisms are required for p53 regulation of G(1) and G(2) checkpoints.


Assuntos
Fase G2/fisiologia , Proteína do Retinoblastoma/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Células Tumorais Cultivadas
11.
J Biol Chem ; 273(46): 30777-84, 1998 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-9804855

RESUMO

There is increasing evidence that prolonged mitotic arrest initiates apoptosis; however, little is known about the signaling pathways involved. Several studies have associated deregulated Cdc2 activity with apoptosis. Herein, we report that the anti-apoptotic protein, Bcl-2, undergoes cell cycle-dependent phosphorylation during mitosis when there is elevated Cdc2 activity. We found that paclitaxel (Taxol(R)) treatment of epithelial tumor cells induced a prolonged mitotic arrest, elevated levels of mitotic kinase activity, hyperphosphorylation of Bcl-2, and subsequent cell death. The Taxol-induced Bcl-2 phosphorylation was dose-dependent. Furthermore, phosphorylated Bcl-2 remained complexed with Bax in Taxol-treated cells undergoing apoptosis. Immunoprecipitation experiments revealed a Bcl-2-associated kinase capable of phosphorylating histone H1 in vitro. However, the kinase was likely not cyclin B1/Cdc2, since cyclin B1/Cdc2 was not detectable in Bcl-2 immunoprecipitates, nor was recombinant Bcl-2 phosphorylated in vitro by cyclin B1/Cdc2. The results of this study further define a link between mitotic kinase activation and the apoptotic machinery in the cell. However, the role, if any, of prolonged Bcl-2 phosphorylation in Taxol-mediated apoptosis awaits further definition of Bcl-2 mechanism of action. Taxol may increase cellular susceptibility to apoptosis by amplifying the normal downstream events associated with mitotic kinase activation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Mitose , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Proteína Quinase CDC2/metabolismo , Morte Celular , Divisão Celular/efeitos dos fármacos , Ciclina B/metabolismo , Ciclina B1 , Fase G2 , Humanos , Fosforilação , Células Tumorais Cultivadas
12.
Cancer Res ; 58(15): 3231-6, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9699647

RESUMO

The G2 cell cycle checkpoint protects cells from potentially lethal mitotic entry after DNA damage. This checkpoint involves inhibitory phosphorylation of Cdc2 at the tyrosine-15 (Y15) position, mediated in part by the Wee1 protein kinase. Recent evidence suggests that p53 may accelerate mitotic entry after DNA damage and that the override of the G2 checkpoint may play a role in the induction of apoptosis by p53. To determine the biochemical mechanism by which p53 inactivates the G2 checkpoint, the effects of p53 activation on Wee1 expression, Cdc2-Y15 phosphorylation, and cyclin B1-associated Cdc2 kinase activity were examined. Under conditions of either growth arrest or apoptosis, p53 activation resulted in the down-regulation of Wee1 expression and dephosphorylation of Cdc2. A parallel increase in cyclin B1/Cdc2 kinase activity was observed during p53-mediated apoptosis. Negative regulation of the Wee1 expression and Cdc2 phosphorylation by p53 was also evident in thymus tissue from p53+/+ mice but not from p53-/- mice. Inactivation of the G2 checkpoint may contribute to the tumor suppressor activity of p53.


Assuntos
Apoptose/fisiologia , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular , Proteínas Nucleares , Proteínas Tirosina Quinases/biossíntese , Proteína Supressora de Tumor p53/fisiologia , Animais , Antineoplásicos/farmacologia , Western Blotting , Divisão Celular/fisiologia , Ciclina B/metabolismo , Ciclina B1 , Regulação para Baixo , Embrião de Mamíferos , Ativação Enzimática , Fibroblastos/citologia , Fase G2/fisiologia , Linfoma de Células T/metabolismo , Camundongos , Nocodazol/farmacologia , Fosforilação , Conformação Proteica , Ratos , Transformação Genética , Células Tumorais Cultivadas
13.
Mol Endocrinol ; 12(8): 1228-40, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9717848

RESUMO

The hypothalamic hormone CRH is also expressed in the placentas of humans and higher primates and may play an important role in the regulation of labor. In choriocarcinoma cell lines, activation of cAMP-dependent pathways increases human (h)CRH reporter gene expression. A cAMP-responsive region distinct from the cAMP response element at -220 bp, has been identified between -200 and -99 bp, and a candidate transcription factor was identified in nuclear extracts of human, but not rodent, choriocarcinoma cell lines. This region, which does not contain a canonical cAMP response element (CRE), transfers protein kinase A responsiveness to a heterologous promoter. Electromobility shift assays and methylation and uracil interference studies localized factor binding to a 20-bp region from -128 to -109 bp of the hCRH promoter. This 20-bp fragment exhibited a similar shift in nuclear extracts from both human term placenta and from human JEG-3 cells. Base contacts, identified in interference studies, were confirmed as critical for binding, as a mutation of these bases abolished factor binding. Furthermore, a CRH promoter containing this mutation exhibited a diminished response to forskolin. UV cross-linking demonstrated the protein in nuclear extracts from human, but not rodent, choriocarcinoma cell lines and estimated its size as 58 kDa. Although this factor participates in cAMP-regulated gene expression, competition electrophoretic mobility assays demonstrated that the factor does not bind to a CRE. Furthermore, neither anti-CREB nor anti-ATF2 antibodies alter factor binding. These data identify this 58-kDa protein as the human-specific CRH activator previously identified as a candidate factor contributing to the species-specific expression of CRH in human placenta.


Assuntos
Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Placenta/metabolismo , Transativadores/metabolismo , Fator 2 Ativador da Transcrição , Sequência de Bases , Sítios de Ligação , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/imunologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Células HeLa/metabolismo , Humanos , Dados de Sequência Molecular , Mutação , Gravidez , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Transativadores/genética , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo , Transfecção , Uracila
14.
Endocrinology ; 137(7): 3000-8, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8770924

RESUMO

CRF, in addition to its role in the hypothalamus, demonstrates species-specific expression in the placentas of higher primates, but not rodents. Transient transfections of BeWo and JEG-3 choriocarcinoma cells, as models for human trophoblasts, demonstrate regulated expression of human (h) CRF-luciferase reporter genes, whereas little or no expression is detected in other lines, including CV-1 cells. The rodent choriocarcinoma cell line, Rcho-1, a model for rodent trophoblasts, is defective in the expression of transfected hCRF genes. The mouse CRF promoter behaves similarly to the corresponding hCRF construct. It is active in BeWo and inactive in Rcho-1 cells. The transcriptional response to cAMP contributes to the specific expression of CRF. Analyses of deleted or mutated hCRF promoters identify a key role for protein kinase A-dependent pathways. A major part, but not all, of this effect is mediated by the canonical cAMP response element conserved in mouse, rat, and human CRF promoters. Additional deletions of the human CRF promoter identify control regions that also contribute to the observed species-specific expression pattern, and each identified region binds factors in nuclear extracts derived from the appropriate cell line. These studies using human and rodent choriocarcinoma cell lines as models of placental trophoblasts demonstrate dominant effects of cellular trans-acting factors, rather than DNA sequence differences, in dictating the species-specific placental expression of CRF.


Assuntos
Hormônio Liberador da Corticotropina/biossíntese , Placenta/metabolismo , Transativadores/metabolismo , Transcrição Gênica , Trofoblastos/fisiologia , Animais , Sequência de Bases , Linhagem Celular , Cloranfenicol O-Acetiltransferase/biossíntese , Coriocarcinoma , Colforsina/farmacologia , AMP Cíclico/metabolismo , Feminino , Expressão Gênica , Humanos , Luciferases/biossíntese , Luciferases/genética , Camundongos , Modelos Biológicos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , Gravidez , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Especificidade da Espécie , Transcrição Gênica/efeitos dos fármacos , Transfecção , Células Tumorais Cultivadas , Neoplasias Uterinas
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