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1.
J Transl Med ; 13: 235, 2015 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-26187646

RESUMO

Inflammation is a key etiologic component in atherogenesis. Previously we demonstrated that adeno-associated virus (AAV) 2/8 gene delivery of Netrin1 inhibited atherosclerosis in the low density lipoprotein receptor knockout mice on high-cholesterol diet (LDLR-KO/HCD). One important finding from this study was that FOXP3 was strongly up-regulated in these Netrin1-treated animals, as FOXP3 is an anti-inflammatory gene, being the master transcription factor of regulatory T cells. These results suggested that the FOXP3 gene might potentially be used, itself, as an agent to limit atherosclerosis. To test this hypothesis AAV2/8 (AAV)/hFOXP3 or AAV/Neo (control) gene therapy virus were tail vein injected into the LDLR-KO/HCD animal model. It was found that hFOXP3 gene delivery was associated with significantly lower HCD-induced atherogenesis, as measured by larger aortic lumen cross sectional area, thinner aortic wall thickness, and lower aortic systolic blood velocity compared with Neo gene-HCD-treated controls. Moreover these measurements taken from the hFOXP3/HCD-treated animals very closely matched those measurements taken from the normal diet (ND) control animals. These data strongly suggest that AAV/hFOXP3 delivery gave a robust anti-atherosclerosis therapeutic effect and further suggest that FOXP3 be examined more stringently as a therapeutic gene for clinical use.


Assuntos
Aterosclerose/terapia , Colesterol na Dieta/sangue , Dependovirus , Fatores de Transcrição Forkhead/genética , Receptores de LDL/genética , Animais , Aorta/diagnóstico por imagem , Aorta/patologia , Aterosclerose/sangue , Aterosclerose/fisiopatologia , Dieta , Terapia Genética/métodos , Humanos , Inflamação/patologia , Masculino , Camundongos , Camundongos Knockout , Linfócitos T Reguladores , Transgenes , Ultrassonografia
2.
Int Rev Immunol ; 34(2): 143-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25901859

RESUMO

The ability of immunotherapy to evoke successful antitumor immune responses has been well documented over the past decade. Despite abundant preclinical data, it is only with the recent approval by the Food and Drug Administration (FDA) of the drugs such as sipuleucel-T and ipilimumab that immunotherapy is finally being recognized as a viable alternative to traditional therapies for treatment of various cancers. Despite the ability of immunotherapy to elicit successful antitumor immune responses, its efficacy is hindered by several factors. Among these are the paucity of tumor-associated antigens (TAA) that can be used as effective targets and the systemic toxicities that often lead to treatment interruption. Indeed, such adverse effects, which can be immunological and/or parenchymal, can be particularly severe and even fatal to some patients. A family of TAA called cancer-testis antigens (CTA) has been identified and their encoding genes have been extensively investigated. CTA expression has been demonstrated in a variety of human cancer tissues, and at least 19 CTA have been found to elicit humoral and/or cellular immune responses in cancer patients. Here we discuss how CTA and immunotherapy will most likely play a major role in the cure of cancer in the light of cancer complexity.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoterapia Adotiva , Neoplasias Testiculares/terapia , Animais , Anticorpos Monoclonais/uso terapêutico , Aprovação de Drogas , Humanos , Ipilimumab , Masculino , Neoplasias Testiculares/imunologia , Extratos de Tecidos/uso terapêutico
3.
Int Rev Immunol ; 33(5): 367-74, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24811209

RESUMO

Sperm protein 17 (Sp17) was originally identified in the flagellum of spermatozoa and subsequently included in the subfamily of tumor-associated antigens known as cancer-testes antigens (CTA). Sp17 has been associated with the motility and migratory capacity in tumor cells, representing a link between gene expression patterns in germinal and tumor cells of different histological origins. Here we review the relevance of Sp17 expression in the mouse embryo and cancerous tissues, and present additional data demonstrating Sp17 complex expression pattern in this murine model. The expression of Sp17 in embryonic as well as adult neoplastic cells, but not normal tissues, suggests this protein should be considered an "oncofetal antigen." Further investigations are necessary to elucidate the mechanisms and functional significance of Sp17 aberrant expression in human adult cells and its implication in the pathobiology of cancer.


Assuntos
Antígenos de Neoplasias/metabolismo , Antígenos de Superfície/metabolismo , Proteínas de Transporte/metabolismo , Células Germinativas/metabolismo , Espermatozoides/metabolismo , Neoplasias Testiculares/metabolismo , Animais , Antígenos de Neoplasias/genética , Antígenos de Superfície/genética , Proteínas de Ligação a Calmodulina , Proteínas de Transporte/genética , Movimento Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana , Camundongos , Metástase Neoplásica , Neoplasias Testiculares/genética
4.
Neurocirugia (Astur) ; 13(6): 491-4, 2002 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-12529780

RESUMO

Acute subdural hematomas are usually neurosurgical emergencies, although a conservative therapy is indicated in selected cases. In some of these patients a progressive resolution is appreciated. However, rapid spontaneous resolution of an acute suddural hematoma is seldom reported. A patient with antecedent of chronic alcoholism and spontaneous resolution of acute subdural hematoma in less than 18 hours after the head injury is described. The possible mechanisms of this rapid resolution are discussed. A tear in the arachnoid with spilling of CSF into the subdural space and the effect of intracranial antihypertensive measures together with cerebral atrophy, are factors that possibly contribute to dilution and redistribution of blood with hematoma disappearing in CT scan.


Assuntos
Hematoma Subdural Agudo/fisiopatologia , Atrofia/etiologia , Atrofia/patologia , Encéfalo/patologia , Hematoma Subdural Agudo/complicações , Hematoma Subdural Agudo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Remissão Espontânea , Tomografia Computadorizada por Raios X
5.
Rev Neurol ; 33(5): 413-6, 2001.
Artigo em Espanhol | MEDLINE | ID: mdl-11727205

RESUMO

INTRODUCTION: Thymectomy is a well established procedure in myasthenia gravis (MG). To reduce its morbidity, treatments which are effective in the short term, such as plasmapheresis and intravenous immunoglobulin (IGI) have been used. OBJECTIVE: To evaluate the efficacy and tolerability of the IGI, compared with plasmapheresis, in the preparation of myasthenic patients before thymectomy. PATIENTS AND METHODS: We compared a group of 33 prospective myasthenic patients treated with IGI with 38 clinical histories taken as controls treated by plasmapheresis during the peri operative period of thymectomy. RESULTS: The patients treated with IGI were in the intensive care unit and neurology ward for less time. The endotracheal tube was also removed sooner. However, these differences were not significant. The commonest complications of IGI were fever, shivering and phlebitis. The most frequent adverse reaction to plasmapheresis were cutaneous eruptions. One patient developed Hepatitis C after plasmapheresis. CONCLUSION: IGI is comparable in efficacy to plasmapheresis in the peri operative period of MG, but has a better profile of adverse reactions.


Assuntos
Anti-Inflamatórios/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/cirurgia , Plasmaferese/métodos , Cuidados Pós-Operatórios , Prednisona/uso terapêutico , Cuidados Pré-Operatórios , Timectomia/métodos , Adulto , Feminino , Humanos , Masculino , Resultado do Tratamento
6.
Cancer Invest ; 19(1): 28-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11291553

RESUMO

The insulin-like growth factor (IGF) system has been shown to regulate prostate cancer cell growth in vitro and, possibly, in vivo. In this study we examined RNA expression of IGF ligands and their receptors in 23 paired benign and neoplastic prostate tissues. In addition to comparing gene expression of IGF ligands and receptors between benign and neoplastic tissue samples, we correlated IGF-I, IGF-II, IGFR-1, and IGFR-2 RNA levels in tumor samples with prognostic clinico-pathological parameters such as stage, grade, Gleason score, perineural or extraprostatic invasion. We found higher IGF-I RNA levels in benign vs. malignant tissues (p = 0.014), whereas IGF-II RNA expression was higher in tumors with high Gleason score (GS) (p = 0.045). Using the Spearman rank correlation test we also found a positive correlation between IGFR-2 RNA levels and GS (p = 0.01). No correlation was found between expression of IGF ligands and receptors and tumor grade, stage perineural invasion, or extraprostatic involvement. We conclude that differential expression of certain IGF system components may be important in the biology and clinical behavior of prostate cancer.


Assuntos
Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Somatomedinas/metabolismo , Expressão Gênica , Humanos , Masculino , Prostatectomia , RNA Mensageiro/análise , Receptores de Somatomedina
7.
Cancer Chemother Pharmacol ; 47(1): 89-93, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11221968

RESUMO

The pharmacokinetics of topotecan have been extensively studied in patients with normal renal function and there is one study of patients with mild to moderate renal insufficiency. However, the effect of hemodialysis on topotecan disposition has not been reported. The objective of this study was to characterize the disposition of topotecan in a patient with severe renal insufficiency receiving hemodialysis. Topotecan lactone disposition was characterized in a patient on and off hemodialysis. The topotecan lactone clearance determined after administration of topotecan alone and with hemodialysis was 5.3 l/h per m(2) vs 20.1 l/h per m2 respectively. At 30 min after the completion of hemodialysis, the topotecan plasma concentration obtained was greater than that measured at the end of hemodialysis (i.e. 8.0 ng/ml vs 4.9 ng/ml), suggesting a rebound effect. The topotecan terminal half-life off dialysis was 13.6 h, compared with an apparent half-life determined during hemodialysis of 3.0 h. These results demonstrate that topotecan plasma clearance while on hemodialysis increased approximately fourfold. Hemodialysis may be an effective systemic clearance process for topotecan and should be considered in selected clinical situations (e.g. inadvertent overdose, severe renal dysfunction).


Assuntos
Antineoplásicos/farmacocinética , Neoplasias Ovarianas/metabolismo , Diálise Renal , Insuficiência Renal/metabolismo , Topotecan/farmacocinética , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Insuficiência Renal/etiologia
9.
J Urol ; 159(4): 1379-83, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9507888

RESUMO

PURPOSE: The insulin-like growth factor (IGF) system appears to be important in human prostate cancer biology. Expression of specific IGF binding proteins (IGFBPs) by prostate cancer tissues may modulate IGF cellular actions, and possibly determine both IGF-dependent tumor growth and biological aggressiveness in vivo. The purpose of this study was to examine the differential expression of all six IGFBP genes in benign and malignant prostate tissue samples. MATERIALS AND METHODS: Using RNAse protection assays, we examined expression of IGFBPs 1 through 6 in 23 paired benign and neoplastic prostate tissue samples obtained from the same prostatectomy specimen. RNA expression levels on each tissue sample were determined densitometrically and groups compared using standard Student's t test. RESULTS: We found expression of IGFBPs 2 through 6, but not IGFBP-1, in both malignant and benign tissues. A statistically significant differential expression of IGFBPs 2, 3 and 5 was found between tumors with high Gleason score and those with low scores and benign tissues. Expression of IGFBPs 2 and 5 was higher (p = 0.002 and 0.04, respectively) while that of IGFBP-3 was lower (p = 0.05) in high versus low Gleason score cancer specimens. Expression of IGFBPs 4 and 6 was no different between tumors (p = 0.052 and 0.25, respectively). No significant differences in IGFBP expression were evident between benign and tumor tissues when tumor grade was not considered. CONCLUSION: Our results indicate that differential expression of certain IGFBPs in human prostate cancer correlates with tumor Gleason score. Thus, expression of certain IGFBPs in prostate cancer may be used as a surrogate marker of aggressive clinical behavior.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/biossíntese , Neoplasias da Próstata/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
10.
Exp Hematol ; 25(5): 405-12, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9168062

RESUMO

The mechanism of corticosteroid alteration of hematopoiesis is not completely elucidated. Employing an endotoxin free system, we examined the mechanisms by which hydrocortisone succinate (HCS) enhanced human bone marrow (BM) colony forming unit granulocyte-macrophage (CFU-GM) proliferation. Interleukin-1beta (IL-1) (1 ng/mL), granulocyte-macrophage colony-stimulating factor (GM-CSF) (1 ng/mL), or the combination, induced minimal CFU-GM proliferation unless HCS was added to the cultures (10-25 vs. 80-125 colonies/4x10(5) BM mononuclear cells). Supernatants produced by incubating mononuclear cells with IL-1 + GM-CSF +/- HCS were examined for their capacity to induce CFU-GM proliferation: IL-1 and/or GM-CSF failed to induce supernatants capable of supporting CFU-GM proliferation unless HCS was present. Analysis of the cytokines produced by mononuclear cell subpopulations demonstrated that HCS markedly enhanced IL-1-induced monocyte secretion of granulocyte (G)-CSF. Furthermore, the minimal effective concentration of IL-1 required to induce G-CSF release was reduced 10-fold (from 1 to 0.1 ng/mL) and the G-CSF released was increased 5-fold at an IL-1 concentration of 1 ng/mL. In contrast, IL-1-induced monocyte secretion of tumor necrosis factor (TNF) was inhibited by HCS. HCS enhanced G-CSF secretion at physiologic concentrations (10 microg/dL), whereas progesterone had no effect. HCS alone had no effect on G-CSF secretion or mRNA expression while IL-1+HCS resulted in a 3-fold increase in G-CSF mRNA levels. These data suggest for the first time that corticosteroids increase secretion of an essential component of the lymphohematopoietic cytokine-growth factor system.


Assuntos
Corticosteroides/farmacologia , Fator Estimulador de Colônias de Granulócitos/metabolismo , Hematopoese/efeitos dos fármacos , Monócitos/metabolismo , Divisão Celular/efeitos dos fármacos , Meios de Cultura/farmacologia , Dactinomicina/farmacologia , Endotoxinas/análise , Endotoxinas/farmacologia , Granulócitos/citologia , Células-Tronco Hematopoéticas/citologia , Humanos , Hidrocortisona/análogos & derivados , Hidrocortisona/antagonistas & inibidores , Hidrocortisona/farmacologia , Interleucina-1/antagonistas & inibidores , Interleucina-1/fisiologia , Cinética , Macrófagos/citologia
11.
P R Health Sci J ; 16(1): 15-22, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9160398

RESUMO

PTHrP has had an unidentified role in medicine since 1930, when Albright described a patient with renal cortical cell carcinoma with hypercalcemia. Since then hypercalcemia has been recognized as the most common paraneoplastic syndrome. At that time the concept of "ectopic PTH syndrome" was introduced, and remained in literature until the true etiology was finally described. In the early 1970's Roof and Benson presented evidence that PTH in humoral hypercalcemia differed from "authentic" PTH. This marked the starting point for researchers to try identifying the molecule that mimicked PTH action and structure. This molecule, named parathyroid-related peptide, has been associated to hypercalcemia seen with solid tumors, such as squamous cell carcinoma of the lung and renal cortical cell carcinoma. PTHrP has been demonstrated to have similar actions to PTH but to differ in decreasing osteoblastic activity while increasing osteoclastic activity. The more fascinating finding was the presence of the PTHrP genes throughout the body, mostly the lactating breast as well as the heart, lungs and skin among others. Despite its identification, finding its physiological roles on normal tissue still remains to be clarified.


Assuntos
Proteínas de Neoplasias/fisiologia , Hormônio Paratireóideo/fisiologia , Proteínas/fisiologia , Sequência de Aminoácidos , Animais , Feminino , Humanos , Hipercalcemia/etiologia , Hipercalcemia/fisiopatologia , Masculino , Dados de Sequência Molecular , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/análise , Proteínas/genética , Proteínas/farmacologia , Receptor Tipo 1 de Hormônio Paratireóideo , Receptores de Hormônios Paratireóideos/fisiologia
12.
P. R. health sci. j ; 16(1): 15-22, Mar. 1997.
Artigo em Inglês | LILACS | ID: lil-228476

RESUMO

PTHrP has had an unidentified role in medicine since 1930, when Albright described a patient with renal cortical cell carcinoma with hypercalcemia. Since then hypercalcemia has been recognized as the most common paraneoplastic syndrome. At that time the concept of ®ectopic PTH syndrome® was introduced, and remained in literature until the true etiology was finally described. In the early 1970's Roof and Benson presented evidence that PTH in humoral hypercalcemia differed from ®authentic® PTH. This marked the starting point for researchers to try identifying the molecule that mimicked PTH action and structure. This molecule, named parathyroid-related peptide, has been associated to hypercalcemia seen with solid tumors, such as squamous cell carcinoma of the lung and renal cortical cell carcinoma. PTHrP has been demonstrated to have similar actions to PTH but to differ in decreasing osteoblastic activity while increasing osteoclastic activity. The more fascinating finding was the presence of the PTHrP genes throughout the body, mostly the lactating breast as well as the heart, lungs and skin among others. Despite its identification, finding its physiological roles on normal tissue still remains to be clarified


Assuntos
Animais , Feminino , Humanos , Proteínas de Neoplasias/fisiologia , Hormônio Paratireóideo/fisiologia , Proteínas/fisiologia , Sequência de Aminoácidos , Hipercalcemia/etiologia , Hipercalcemia/fisiopatologia , Dados de Sequência Molecular , Proteínas/análise , Proteínas/genética , Proteínas/farmacologia , Receptores de Hormônios Paratireóideos/fisiologia
13.
Pharmacotherapy ; 17(1): 163-5, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9017777

RESUMO

Paclitaxel is an antineoplastic agent derived from the bark of the Pacific yew tree that has activity against many tumors including breast and ovarian carcinomas. In the past, its extravasation quality has been considered to be a local irritant; however, recent reports suggest that the agent may be a vesicant. A patient experienced a delayed vesicant reaction to a paclitaxel extravasation that resulted in severe necrosis. No acute symptoms were reported at the time of extravasation from the 24-hour peripheral paclitaxel infusion. However, on day 11 the patient complained of severe and progressive pain at the site of extravasation. The site was erythematous and had areas of central necrosis requiring debridement and closure by a plastic surgeon. Because paclitaxel possesses vesicant characteristics, health care professionals should be aware of its potential extravasation hazard. Prolonged peripheral infusions should be avoided or administered with extreme caution.


Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Toxidermias/etiologia , Extravasamento de Materiais Terapêuticos e Diagnósticos , Paclitaxel/efeitos adversos , Neoplasias da Coluna Vertebral/tratamento farmacológico , Antineoplásicos Fitogênicos/administração & dosagem , Toxidermias/patologia , Feminino , Antebraço , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Necrose , Paclitaxel/administração & dosagem , Neoplasias da Coluna Vertebral/secundário
14.
J Natl Cancer Inst ; 88(9): 601-6, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8609661

RESUMO

BACKGROUND: The insulin-like growth factor (IGF)-binding proteins (IGFBPs) regulate the actions of the IGFs by influencing interactions between the IGFs and the IGF receptors. IGFBP-3, one of the six known species of IGFBPs, is the predominant IGFBP in serum and is expressed by breast cancer cells. Compared with estrogen receptor (ER)-positive samples, ER-negative breast cancer cell lines and tumors express higher levels of IGFBP-3. Therefore, expression of IGFBP-3 may be relevant in breast cancer biology, although it is unknown whether IGFBP-3 levels correlate with other breast cancer prognostic factors besides ER status. It is also not known how different methods used to measure IGFBP-3 in breast cancer correlate. PURPOSE: We measured IGFBP-3 messenger RNA (mRNA) and protein levels in breast tumors by different methods to test how these methods compare and to investigate the relationship between IGFBP-3 and breast cancer prognostic factors. METHODS: We analyzed 40 human breast tumors and examined IGFBP-3 expression by ligand blot analysis, immunoblot analysis, immunoradiometric assay (IRMA), and ribonuclease protection assay. Another set of 40 breast tumors, selected according to ER and progesterone receptor (PR) status, S phase, and ploidy, was analyzed by IRMA. RESULTS: In 26 (65%) of 40 samples in which RNA could be isolated, IGFBP-3 mRNA levels correlated with IGFBP-3 levels measured by IRMA (two-sided; P = .0001) but not with IGFBP-3 levels measured by ligand blot or immunoblot. Protein levels were highly correlated among all protein assays. Because the IRMA was more sensitive and accurate than the ligand blot and immunoblot assays, we used IRMA to examine IGFBP-3 levels in an additional 20 primary breast tumors with poor prognostic features (ER and PR negativity, high S phase, and aneuploidy) and in 20 tumors with good prognostic factors (opposite features). IGFBP-3 levels were threefold higher in tumors with poor prognostic features (mean +/- standard deviation = 32.8 +/- 25.2 versus 11.8 +/- 9.7 ng/mg; two-sided; P = .003). CONCLUSIONS: These findings suggest that in human breast cancer, IGFBP-3 mRNA and protein levels are correlated and higher levels of IGFBP-3 are detectable in tumors with poor prognostic features. IMPLICATIONS: IGFBP-3 may be involved in the regulation of breast cancer cell growth.


Assuntos
Neoplasias da Mama/química , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Aneuploidia , Autorradiografia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Densitometria/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Hemoglobinas/análise , Humanos , Immunoblotting , Ensaio Imunorradiométrico , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteínas de Neoplasias/análise , Valor Preditivo dos Testes , Prognóstico , RNA Mensageiro/análise , RNA Neoplásico/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Análise de Regressão , Fase S
15.
J Clin Endocrinol Metab ; 80(12): 3476-82, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8530586

RESUMO

In this study, we examined the expression of insulin-like growth factor (IGF) ligands, receptors, (IGFR1, IGFR2), and binding proteins (IGFBPs) in the human prostate cancer cell line DU145, as well as its mitogenic response to the IGFs. Using RNase protection assays, we found expression of IGF-II, IGFR1, and IGFR2 but failed to detect IGF-I messenger RNA. Distinct binding protein species as well as immunoreactive IGF-II were detected in conditioned media using radioligand and immunoblotting assays. Compared with controls, treatment with exogenous IGF-I and IGF-II resulted in stimulation of monolayer and anchorage-independent growth. Recombinant human IGFBP-1, which binds IGF-II with high affinity, inhibited IGF-II-induced monolayer growth and both baseline and IGF-II-induced anchorage-independent growth in this cell line. Our data suggest IGF-II is as an autocrine growth factor in DU145 cells, and that inhibition of IGF-II-dependent growth of human prostate cancer cells may represent a new therapeutic strategy for this disease.


Assuntos
Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Fator de Crescimento Insulin-Like II/fisiologia , Neoplasias da Próstata/patologia , Western Blotting , Divisão Celular/efeitos dos fármacos , Meios de Cultivo Condicionados , Feminino , Humanos , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/farmacologia , Masculino , Fosforilação , RNA Mensageiro/metabolismo , Receptores de Somatomedina/genética , Proteínas Recombinantes , Células Tumorais Cultivadas
16.
Cancer Lett ; 77(1): 25-32, 1994 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-7512885

RESUMO

Eighty breast cancer specimens were examined for insulin-like growth factor binding protein (IGFBP) expression by ligand blotting. Five distinct IGFBP species were found: a doublet at 48 and 44 kDa was IGFBP-3, the 34-kDa band was IGFBP-2, and a band at 24 kDa was IGFBP-4. A 32-kDa band was compatible with the migration position reported for IGFBP-5. IGFBP-3 was inversely correlated with ER expression, while IGFBP-4 was positively correlated with both ER and PgR. IGFBP-4 was also inversely correlated with S-phase fraction. Thus, IGFBP expression correlates with other parameters of breast cancer biology and may play a role in regulating tumor growth.


Assuntos
Neoplasias da Mama/química , Proteínas de Transporte/análise , Somatomedinas/metabolismo , Neoplasias da Mama/patologia , Divisão Celular , Feminino , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Receptores de Estrogênio/análise , Receptores de Progesterona/análise
17.
Cell Growth Differ ; 5(1): 73-7, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7510125

RESUMO

Interactions between insulin-like growth factor I (IGF-I) and the type of I IGF receptor may be affected by high-affinity extracellular binding proteins. To date, six distinct IGF binding proteins (IGFBPs) have been identified, but their physiological roles are not well understood. For example, depending on experimental conditions, IGFBP-1 has been shown to both enhance and inhibit IGF-I mediated mitogenesis. We have previously shown that excess exogenous IGFBP-1 inhibited IGF-I mediated growth of MCF-7 cells. In this study, we examined whether or not endogenously expressed IGFBP-1 could interfere with IGF-I mediated growth of MCF-7 cells. Cells were stably transfected with an IGFBP-1 expression vector. IGFBP-1 mRNA was produced by the cells, and protein was detected in the conditioned media by ligand blot and immunoblot. Type I IGF receptor could not be phosphorylated by IGF-I in cells expressing IGFBP-1; however, an IGF-I analogue (Arg-3-IGF-I), which cannot complex with IGFBPs, stimulated receptor phosphorylation. IGF-I did not stimulate cell growth in IGFBP-1 expressing cells. These results suggest that IGFBP-1 expression in MCF-7 breast cancer cells inhibits IGF-I induced growth by interrupting the interaction between IGF-I and its receptor.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Transporte/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , Receptor IGF Tipo 1/fisiologia , Neoplasias da Mama/patologia , Divisão Celular/fisiologia , Feminino , Humanos , Técnicas In Vitro , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Fosforilação , Plasmídeos , Receptor IGF Tipo 1/metabolismo , Células Tumorais Cultivadas
18.
J Cell Physiol ; 157(2): 229-36, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7693722

RESUMO

The insulin-like growth factors (IGFs) are potent mitogens for breast cancer cells and their activity is modulated by high affinity binding proteins (IGFBPs). We have recently shown that IGFBP-1 purified from human amniotic fluid neutralizes IGF-I-dependent growth of MCF-7 cells. In this study we examined the effects of recombinant IGFBP-1 (rBP-1) on IGF-I, estradiol (E2), and serum-induced monolayer and anchorage independent growth (AIG) of MCF-7 cells. Under serum-free conditions, rBP-1 had no effect on MCF-7 basal monolayer growth. However, 40 nM rBP-1 completely blocked the mitogenic action of both IGF-I and 5% charcoal stripped serum (CSS). This concentration of rBP-1 partially inhibited E2-induced growth, while 80 nM rBP-1 completely abolished E2 mitogenicity. The addition of either excess IGF-I or 5 nM [Arg3]IGF-I, a species that does not bind IGFBPs, neutralized rBP-1 inhibitory effects. In AIG assays, 80 nM rBP-1 reduced colony number by at least 70% and decreased colony size in all treatment groups compared to control. We examined rBP-1 effects on both IGF-I binding to MCF-7 membranes and activation of type I IGF receptor (IGFR1) and found that 80 nM rBP-1 reduced IGF-I receptor binding to levels of nonspecific binding and completely abolished ligand-dependent IGFR1 phosphorylation. However, neither treatment with 5% CSS nor exposure to E2 resulted in IGFR1 phosphorylation suggesting that different mechanism(s) are responsible for rBP-1 inhibitory action under this condition. Our data suggest rBP-1 may serve as an antagonist of human breast cancer growth by interfering with growth factor-mediated cell proliferation.


Assuntos
Proteínas Sanguíneas/farmacologia , Neoplasias da Mama/patologia , Proteínas de Transporte/farmacologia , Estradiol/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Análise de Variância , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Immunoblotting , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Fosforilação , Testes de Precipitina , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas
19.
J Cell Biochem ; 52(2): 196-205, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7690042

RESUMO

The insulin-like growth factors (IGFs) have been implicated in the growth regulation of human breast cancer. Since the IGFs are associated with specific binding proteins (IGFBPs) which may modulate receptor/ligand interactions, production of IGFBPs by breast cancer cells could alter their IGF-dependent growth. This study examined the expression of IGFBPs 4, 5, and 6 in eight breast cancer cell lines (BCCLs) using ribonuclease (RNase) protection assays. IGFBP-4 mRNA was detected in all BCCLs studied. IGFBP-5 expression was higher in estrogen receptor (ER) positive cells, while IGFBP-6 mRNA was detected in only two ER negative BCCLs. We also found that E2 treatment enhanced the expression of IGFBPs 2, 4, and 5 in T47-D cells. We next studied IGFBP mRNA expression in 40 primary breast tumors. All tumors expressed mRNA for IGFBPs 2-6 but none expressed IGFBP-1 message. IGFBP-3 expression was higher in ER negative tumors, while that of IGFBP-4 and -5 was higher in ER positive specimens. These differences were statistically significant (P < .05). Ligand blot analysis of tumor extracts confirmed the presence of IGFBPs in breast cancer tissues. Thus, differential IGFBP expression in ER positive and negative tumors suggests an important role for this protein in breast cancer biology.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Transporte/biossíntese , Receptores de Estrogênio/metabolismo , Somatomedinas/metabolismo , Western Blotting , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Humanos , Immunoblotting , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , RNA Mensageiro/biossíntese , Células Tumorais Cultivadas
20.
Am J Med Sci ; 305(3): 176-82, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7680528

RESUMO

Approximately 115,000 new cases of axillary node negative breast cancer were diagnosed in this country last year. Since about 20-30% of these patients will ultimately relapse and die of their disease, adjuvant systemic therapy has been advocated for this group to decrease the relapse rate and prolong survival. However, although most clinical trials have demonstrated a modest impact on disease recurrence, the available data have failed to show consistent improvements in overall survival and does not justify the generalized use of systemic treatment in this patient subgroup. For this reason, a plethora of prognostic factors have been described to identify those patients with a higher risk of recurrence to concentrate therapeutic options in this specific group. Of all the disease prognosticators studied, tumor size, nuclear grade, and proliferative indexes appear to correlate well with tumor recurrence. In addition, biologic characteristics of primary tumors such as the presence of hormone and growth factor receptors, secretion of specific polypeptides and proteases, expression of proto-oncogenes, and abnormalities in tumor suppressor genes have been shown to be potentially useful as prognostic indicators in patients with early breast cancer. Despite these provocative data, larger clinical trials are necessary before incorporating these parameters in the routine evaluation of patients with axillary node negative breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Proteínas , Neoplasias da Mama/patologia , Catepsina D/metabolismo , Divisão Celular , Receptores ErbB/metabolismo , Fator VIII/análise , Genes Supressores de Tumor , Proteínas de Choque Térmico/metabolismo , Humanos , Metástase Linfática , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica , Ploidias , Prognóstico , Proto-Oncogenes , Receptores de Estrogênio/análise , Fator Trefoil-1 , Proteínas Supressoras de Tumor
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