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1.
BMC Cancer ; 21(1): 207, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648461

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide; it is the fourth leading cause of death in the world and the third in Brazil. Mutations in the APC, DCC, KRAS and TP53 genes have been associated with the progression of sporadic CRC, occurring at defined pathological stages of the tumor progression and consequently modulating several genes in the corresponding signaling pathways. Therefore, the identification of gene signatures that occur at each stage during the CRC progression is critical and can present an impact on the diagnosis and prognosis of the patient. In this study, our main goal was to determine these signatures, by evaluating the gene expression of paired colorectal adenoma and adenocarcinoma samples to identify novel genetic markers in association to the adenoma-adenocarcinoma stage transition. METHODS: Ten paired adenoma and adenocarcinoma colorectal samples were subjected to microarray gene expression analysis. In addition, mutations in APC, KRAS and TP53 genes were investigated by DNA sequencing in paired samples of adenoma, adenocarcinoma, normal tissue, and peripheral blood from ten patients. RESULTS: Gene expression analysis revealed a signature of 689 differentially expressed genes (DEG) (fold-change> 2, p< 0.05), between the adenoma and adenocarcinoma paired samples analyzed. Gene pathway analysis using the 689 DEG identified important cancer pathways such as remodeling of the extracellular matrix and epithelial-mesenchymal transition. Among these DEG, the ETV4 stood out as one of the most expressed in the adenocarcinoma samples, further confirmed in the adenocarcinoma set of samples from the TCGA database. Subsequent in vitro siRNA assays against ETV4 resulted in the decrease of cell proliferation, colony formation and cell migration in the HT29 and SW480 colorectal cell lines. DNA sequencing analysis revealed KRAS and TP53 gene pathogenic mutations, exclusively in the adenocarcinomas samples. CONCLUSION: Our study identified a set of genes with high potential to be used as biomarkers in CRC, with a special emphasis on the ETV4 gene, which demonstrated involvement in proliferation and migration.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Neoplasias Colorretais/genética , Genes Neoplásicos , Proteínas de Neoplasias/fisiologia , Proteínas Proto-Oncogênicas c-ets/fisiologia , Adenocarcinoma/química , Adenocarcinoma/patologia , Adenoma/química , Adenoma/patologia , Idoso , Biomarcadores Tumorais/genética , Brasil , Divisão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/química , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-ets/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-ets/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Análise Serial de Tecidos , Transcriptoma , Ensaio Tumoral de Célula-Tronco
2.
Braz. j. med. biol. res ; 51(2): e6808, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889020

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Imuno-Histoquímica , Biomarcadores Tumorais/análise , Adenoma/genética , Adenoma/química , Expressão Gênica , Estudos Transversais , Gradação de Tumores
3.
Braz J Med Biol Res ; 51(2): e6808, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267504

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Neoplasias Hipofisárias/patologia , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/química , Adenoma/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Antígeno CD56/análise , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Hipofisárias/química , Neoplasias Hipofisárias/genética , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Adulto Jovem
4.
Endocrinol Nutr ; 61(10): 523-30, 2014 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25008035

RESUMO

OBJECTIVE: To evaluate expression of somatostatin receptor subtypes 2 and 5 (SSTR 2 and 5) by RT/PCR and immunohistochemistry (IHC) in GH-secreting adenomas, seeking correlations with response to octreotide. METHODS: SSTR2 and 5 expression was tested by IHC (n=37), RT/PCR (n=36) or both (n=13) in GH-secreting adenomas from 60 patients with acromegaly who had undergone pituitary surgery; 36 had been treated preoperatively with octreotide LAR for 3-6 months, and were categorized as responders (achievement of GH <2.5ng/mL and a normal age-adjusted IGF-1), partial responders (GH and IGF-1 reduction >50% and >30%, respectively) or non-responders. IHC was performed on a tissue microarray using specific antibodies directed to the carboxyl terminus of SSTR2 and 5. RESULTS: SSTR5 was the predominantly expressed receptor subtype by both IHC and RT/PCR in all tumors tested, regardless of whether they came from octreotide-naïve, octreotide-responsive, or octreotide-resistant patients. Immunostaining was concentrated in the cytoplasm. Neither SSTR2 nor SSTR5 expression correlated with baseline or post-octreotide GH or IGF-1 levels or tumor volume by either method. The agreement rate between RT/PCR and IHC was 77% in all 13 adenomas in which both methods were used. CONCLUSION: Expression of these receptors does not guarantee an adequate response to somatostatin analogs; other functional aspects of this interaction, such as receptor homo- and heterodimerization, and the resulting signaling cascade, probably play a role in determining whether a patient will respond or not to these agents.


Assuntos
Adenoma/química , Adenoma Hipofisário Secretor de Hormônio do Crescimento/química , Hormônio do Crescimento Humano/metabolismo , Proteínas de Neoplasias/biossíntese , Octreotida/uso terapêutico , Receptores de Somatostatina/biossíntese , Acromegalia/etiologia , Adenoma/complicações , Adenoma/tratamento farmacológico , Adenoma/cirurgia , Antineoplásicos Hormonais/uso terapêutico , Terapia Combinada , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Adenoma Hipofisário Secretor de Hormônio do Crescimento/complicações , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/cirurgia , Hormônio do Crescimento Humano/análise , Humanos , Hipofisectomia , Fator de Crescimento Insulin-Like I/análise , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Somatostatina/genética , Análise Serial de Tecidos
5.
Clinics (Sao Paulo) ; 68(9): 1220-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24141838

RESUMO

OBJECTIVE: Thymosin beta 4 (Tß4) is a ubiquitous peptide that plays pivotal roles in the cytoskeletal system and in cell differentiation. Recently, a role for Tß4 has been proposed in experimental and human carcinogenesis, including gastrointestinal cancer. This study was aimed at evaluating the relationship between Tß4 immunoreactivity and the initial steps of carcinogenesis. METHODS: In total, 60 intestinal biopsies, including 10 hyperplastic polyps, 10 sessile serrated adenomas/polyps, 15 colorectal adenomas with low-grade dysplasia, 15 adenomas with high-grade dysplasia, 15 adenocarcinomas and 10 samples of normal colon mucosa, were analyzed for Tß4 expression by immunohistochemistry. RESULTS: Weak cytoplasmic reactivity for Tß4 was detected in the normal colon mucosa. No reactivity for Tß4 was found in hyperplastic and sessile serrated polyps/adenomas. Tß4 expression was observed in 10/15 colorectal adenocarcinomas. In adenomas with low-grade dysplasia, Tß4 immunoreactivity was mainly detected in dysplastic glands but was absent in hyperplastic glands. Tß4 immunoreactivity was characterized by spot-like perinuclear staining. In high-grade dysplastic polyps, immunostaining for Tß4 appeared diffuse throughout the entire cytoplasm of dysplastic cells. Spot-like perinuclear reactivity was detected in adenocarcinoma tumor cells. CONCLUSIONS: Our study shows for the first time that Tß4 is expressed during different steps of colon carcinogenesis. The shift of Tß4 immunolocalization from low-grade to high-grade dysplastic glands suggests a role for Tß4 in colorectal carcinogenesis. However, the real meaning of Tß4 reactivity in dysplastic intestinal epithelium remains unknown.


Assuntos
Adenoma/química , Colo/química , Neoplasias do Colo/química , Pólipos do Colo/química , Proteínas de Neoplasias/análise , Timosina/análise , Adenoma/patologia , Biópsia , Diferenciação Celular , Colo/patologia , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino
6.
Clinics ; 68(9): 1220-1224, set. 2013. graf
Artigo em Inglês | LILACS | ID: lil-687759

RESUMO

OBJECTIVE: Thymosin beta 4 (Tβ4) is a ubiquitous peptide that plays pivotal roles in the cytoskeletal system and in cell differentiation. Recently, a role for Tβ4 has been proposed in experimental and human carcinogenesis, including gastrointestinal cancer. This study was aimed at evaluating the relationship between Tβ4 immunoreactivity and the initial steps of carcinogenesis. METHODS: In total, 60 intestinal biopsies, including 10 hyperplastic polyps, 10 sessile serrated adenomas/polyps, 15 colorectal adenomas with low-grade dysplasia, 15 adenomas with high-grade dysplasia, 15 adenocarcinomas and 10 samples of normal colon mucosa, were analyzed for Tβ4 expression by immunohistochemistry. RESULTS: Weak cytoplasmic reactivity for Tβ4 was detected in the normal colon mucosa. No reactivity for Tβ4 was found in hyperplastic and sessile serrated polyps/adenomas. Tβ4 expression was observed in 10/15 colorectal adenocarcinomas. In adenomas with low-grade dysplasia, Tβ4 immunoreactivity was mainly detected in dysplastic glands but was absent in hyperplastic glands. Tβ4 immunoreactivity was characterized by spot-like perinuclear staining. In high-grade dysplastic polyps, immunostaining for Tβ4 appeared diffuse throughout the entire cytoplasm of dysplastic cells. Spot-like perinuclear reactivity was detected in adenocarcinoma tumor cells. CONCLUSIONS: Our study shows for the first time that Tβ4 is expressed during different steps of colon carcinogenesis. The shift of Tβ4 immunolocalization from low-grade to high-grade dysplastic glands suggests a role for Tβ4 in colorectal carcinogenesis. However, the real meaning of Tβ4 reactivity in dysplastic intestinal epithelium remains unknown. .


Assuntos
Feminino , Humanos , Masculino , Adenoma/química , Colo/química , Neoplasias do Colo/química , Pólipos do Colo/química , Proteínas de Neoplasias/análise , Timosina/análise , Adenoma/patologia , Biópsia , Diferenciação Celular , Colo/patologia , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Progressão da Doença , Imuno-Histoquímica
7.
Ann Diagn Pathol ; 10(6): 333-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17126250

RESUMO

The aim of this prospective study is to establish the frequency and the type (neoplastic and nonneoplastic) lesions defined endoscopically as flat elevated lesion (FEL) in the colon and rectum, as well as to compare flat adenomas (FAs) to polypoid lesions of the same size with morphometric and immunohistochemical analysis. One hundred nineteen patients were studied through fibrocolonoscopy with chromoscopy (indigo carmine spray). All detected lesions (total of 195) were removed, and FELs measuring 10 mm or smaller were also selected. Using histopathologic criteria, they were divided in neoplastic (adenomas and carcinomas) and nonneoplastic ones. In neoplastic lesions, the following parameters were evaluated to compare FAs with polypoid lesions: morphometric studies with Index of Structural Atypia (ISA) and Stratification Index (SI), evaluation of cellular proliferation with label index of Ki-67, and expression of p53 protein. Of 195 lesions resected, only 33 (17%) met the endoscopic requirements for FELs. Twelve (36.4%) were neoplastic and 21 (63.6%) considered nonneoplastic. Among the FAs, there were a percentage of high-grade (severe dysplasia) significantly more frequent than observed in polypoid lesions (16.7% vs 2.6%). In addition, the SI, Ki-67 label index and p53 positivity were significantly higher in FAs. The ISA also reached significant differences between both groups of adenomas. Non-neoplastic FELs included different entities such as hyperplasic polyps, focuses of colitis, normal mucosa, and scars. The endoscopic elements analyzed were shared between nonneoplastic FELs and FAs. A central depression, when air was properly insufflated, considered typical in neoplastic lesions, was frequently observed in nonneoplastic lesions. Following the endoscopic criteria of FELs, nonneoplastic lesions predominated over the adenomatous lesions, demonstrating that FELs and FAs are not homologous terms. The frequency of high-grade dysplasia was significantly more elevated in the adenomatous FELs than in polypoid adenomas. The ISA, SI, p53 expression, and Ki-67 label index were helpful in differentiating adenomatous FELs from polypoid lesions. Flat elevated lesions selected by endoscopic criteria are, in fact, a heterogeneous population of lesions.


Assuntos
Adenocarcinoma/patologia , Adenoma/patologia , Neoplasias do Colo/patologia , Endoscopia Gastrointestinal/métodos , Neoplasias Retais/patologia , Adenocarcinoma/química , Adenoma/química , Idoso , Biomarcadores Tumorais/análise , Proliferação de Células , Colite/patologia , Doenças do Colo/metabolismo , Doenças do Colo/patologia , Neoplasias do Colo/química , Neoplasias do Colo/classificação , Pólipos do Colo/patologia , Feminino , Humanos , Antígeno Ki-67/análise , Antígeno Ki-67/metabolismo , Masculino , Estudos Prospectivos , Neoplasias Retais/química , Neoplasias Retais/classificação , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/metabolismo
8.
Clin Endocrinol (Oxf) ; 62(6): 672-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15943828

RESUMO

OBJECTIVE: Type I iodothyronine deiodinase (D1) catalyses the 5' monodeiodination of T4 and is highly expressed in normal human thyroid gland. We have investigated D1 expression in a series of benign and malignant differentiated thyroid neoplasias. DESIGN: Surgically isolated thyroid tumour fragments were used. D1 expression was determined by reverse transcription polymerase chain reaction (RT-PCR) and enzymatic assay. PATIENTS: Tumours and adjacent normal tissues were obtained from 28 unselected patients (papillary carcinoma, n = 14; follicular adenoma, n = 7; follicular carcinoma, n = 6; anaplastic carcinoma, n = 1). MEASUREMENTS: D1 mRNA levels were determined using specific primers for the human D1 gene and enzymatic assays were performed using T4 as substrate. RESULTS: In papillary thyroid carcinoma (PTC), D1 mRNA and activity levels were decreased compared with the surrounding tissue (0.25 +/- 0.24 vs. 1.09 +/- 0.54 arbitrary units (AU), P < 0.001 and 0.08 +/- 0.07 vs. 0.24 +/- 0.15 pmol T4/min/mg protein, P = 0.045, respectively). Decreased D1 expression was consistent and was observed in all histological subtypes and clinical stages analysed, including microcarcinomas. By contrast, significantly higher D1 mRNA levels and enzyme activity were present in follicular adenoma (1.9 +/- 1.5 vs. 0.83 +/- 0.58 AU, P = 0.028 and 2.67 +/- 1.42 vs. 0.22 +/- 0.06 pmol T4/min/mg protein, P = 0.044, respectively) and in follicular thyroid carcinoma (FTC) than in surrounding normal tissue (1.2 +/- 0.46 vs. 0.67 +/- 0.18 AU, P = 0.038 and 1.20 +/- 0.58 vs. 0.20 +/- 0.10 pmol T4/min/mg protein, P < 0.001, respectively). Type II iodothyronine deiodinase (D2) activity was also significantly higher in metastatic FTC samples than in normal thyroid tissues (5.20 +/- 0.81 vs. 0.30 +/- 0.27 fmol T4/min/mg protein, P < 0.001). CONCLUSIONS: These findings suggest that thyroid cell dedifferentiation promotes changes in D1 gene expression by pretranscriptional mechanisms and indicate that decreased D1 expression might be an early and discrete event in thyroid cell dedifferentiation towards papillary thyroid carcinoma.


Assuntos
Biomarcadores Tumorais/química , Carcinoma Papilar/química , Iodeto Peroxidase/análise , Neoplasias da Glândula Tireoide/química , Adenoma/química , Adulto , Idoso , Carcinoma/química , Carcinoma Papilar, Variante Folicular/química , Feminino , Humanos , Iodeto Peroxidase/genética , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Rev Med Chil ; 132(3): 279-84, 2004 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-15376563

RESUMO

BACKGROUND: Follicular carcinomas account for 15% of thyroid malignant tumors. The differential diagnosis between adenoma and minimally invasive follicular carcinoma is difficult and lacks reproducibility especially in frozen sections. As the diagnosis depends on finding foci of capsular invasion, multiple sections must be examined. Numerous immunohistochemical markers have been studied for determining malignancy. AIM: To assess the efficacy of HBME-1 and Cyclin-D1 as diagnostic markers for follicular thyroid carcinoma. MATERIAL AND METHOD: We evaluated retrospectively 21 thyroidectomy specimens of 18 women and 3 men with diagnosis of adenoma or follicular carcinomas, both by hematoxylin and eosin stain and by immunohistochemistry using the avidin biotin method for the markers HBME-1 and Cyclin D1. RESULTS: The sensitivity and specificity of HBME-1 for the diagnosis of follicular thyroid carcinoma, were 88.9% and 100%, respectively whereas for Cyclin D1 the sensitivity and specificity were 22.2% and 100%, respectively. There were no false positive cases. CONCLUSIONS: HBME-1 has excellent sensitivity and specificity for the diagnosis of follicular carcinoma.


Assuntos
Adenocarcinoma Folicular/diagnóstico , Biomarcadores Tumorais/análise , Ciclina D1/análise , Neoplasias da Glândula Tireoide/diagnóstico , Adenocarcinoma Folicular/química , Adenoma/química , Adenoma/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/química
10.
Int J Oral Maxillofac Surg ; 33(6): 621-4, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15308267

RESUMO

Sialadenoma papilliferum (SP) is a rare benign tumour of salivary gland origin, which has been included among the ductal papillomas in the latest classification of tumours by the World Health Organisation. Two SP from the minor salivary gland of the palate of middle age patients were presented and studied by immunohistochemical. Our results showed presence of cytokeratins (CKs) 13, 14, 7, 8, 19 and absence of vimentin and smooth muscle actin. This immunoprofile is similar to the excretory duct of salivary gland.


Assuntos
Adenoma/química , Neoplasias das Glândulas Salivares/química , Glândulas Salivares Menores/química , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Masculino , Pessoa de Meia-Idade , Neoplasias Palatinas/química , Palato Duro/química , Palato Mole/química
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