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1.
J Carcinog ; 8: 11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19491505

RESUMO

BACKGROUND: The hypothalamic luteinizing hormone-releasing hormone (LHRH) is well known for its role in the control of pituitary gonadotropin secretion and it has demonstrated a direct antiproliferative effect on some cancer cell lines of LHRH and its synthetic analogs. The study was designed to assess whether administration of the LHRH analog (goserelin) has any effect on the expression of the vascular endothelial growth factor (VEGF) and the epidermal growth factor receptor (EGFR) in rats with N-nitroso-N-methylurea (NMU)-induced-mammary tumors " in vivo". MATERIALS AND METHODS: The animals with tumors were assessed after acute or chronic treatment with goserelin, and in all the animals VEGF and EGFR expression was examined both in plasma and tumor homogenates by enzyme immunoassay. RESULTS: The basal plasma values of VEGF were lower in the healthy control group than in rats with NMU-induced tumors ( P = 0.025). Following acute treatment with goserelin, VEGF expression in plasma increased above basal levels after 60 min ( P = 0.05) and dropped during chronic treatment. Likewise, in the tumor homogenate the mean VEGF expression was higher at 60 min post-goserelin administration than the basal levels, although VEGF expression then diminished at 90 min. Plasma EGFR expression was higher in rats with NMU-induced tumors than in healthy controls ( P Conclusions: The results allow us to conclude that goserelin may exert a short-term stimulatory effect on the release of VEGF, as well as a long-term inhibitory effect on VEGF but not EGFR expression.

2.
Oncology ; 76(6): 435-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19420965

RESUMO

The cannabinoid receptor-1 (CNR-1) and endogenous agonists of this receptor are present in the central and peripheral nervous systems including the gastrointestinal nervous system. The surgically rejected specimens of human colorectal cancers and paired normal tissues were studied to detect mutations in the CNR1 gene by sequencing method. The results were compared to clinicopathological parameters and correlated with overall survival time. Sixty-three colorectal cancer patients, who underwent surgical excision of colorectal carcinoma, were included in this study. The coding region of the CNR1 gene was studied: a nucleotide change (G-->A) at position 1359 was identified by direct sequencing of PCR. Thirty-eight patients had the G/G genotype (wild type) in tumor areas and 25 patients had G/A heterozygous or A/A homozygous genotype. Univariate analysis revealed 2 independent variables associated with CNR1 gene mutation. The results show that the patients with Dukes stage C and D had a 2.9 times (p = 0.04) and patients that were lymph node positive had 2.8 times (p = 0.05) greater probability of nucleotide change in CNR1 gene. Genotype G/A plus A/A had a shorter overall survival time than G/G wild-type patients (p < 0.05). Indeed nontumor paired colorectal tissues showed nucleotide change. A large number of patients with mutation in the CNR1 gene were observed. These preliminary findings highlight the importance of further studies in the use of cannabinoid analogs as receptor ligands to analyze potential therapeutic effects.


Assuntos
Carcinoma/genética , Carcinoma/mortalidade , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Mutação Puntual , Receptor CB1 de Canabinoide/genética , Idoso , Carcinoma/terapia , Neoplasias Colorretais/terapia , Feminino , Heterozigoto , Homozigoto , Humanos , Ligantes , Masculino , Pessoa de Meia-Idade , Risco , Análise de Sequência de DNA , Resultado do Tratamento
3.
Tumori ; 95(1): 68-75, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19366059

RESUMO

AIMS AND BACKGROUND: Cannabinoid receptors have an impact on gastrointestinal function, but it remains unknown whether mutations may affect tumor susceptibility in patients with esophageal carcinoma. The aim of this study was to determine mutation in the cannabinoid receptor-1 (CNR1) gene and its relation to vascular endothelial growth factor (VEGF) expression as an angiogenic and poor prognostic factor. METHODS: 179 esophageal tissue samples from 69 patients (29 with esophageal cancer and 40 controls) were studied. CNR1 gene mutation (1359 G --> A in codon 453) was detected with PCR, using the MspI restriction enzyme. VEGF was determined by immunoassay. RESULTS: Genotyping in control patients' samples revealed that 24/40 were G/G wild type and 16/40 were G/A; no samples were A/A. Of the 139 tissue samples from the 29 esophageal cancer patients, 15 were G/G homozygous, 85 G/A heterozygous, 11 had an A/A genotype and 28 were without amplification. In the normal tissue adjacent to tumor, some mutations were observed. The overall survival time was reduced in patients with the A/A type in all their 5 samples, in comparison to G/G type (P = 0.04, chi-square: 4.26). VEGF expression was higher in tumor than nontumor areas (P < 0.025). VEGF expression was not correlated with survival time. CONCLUSIONS: Our preliminary findings in esophageal tissue showed a high frequency of G --> A mutation in the CNR1 gene. No correlation between VEGF expression and gene receptor mutation was found. Patients with mutation in all their samples had a reduced survival time.


Assuntos
Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Receptor CB1 de Canabinoide/genética , Fator A de Crescimento do Endotélio Vascular/biossíntese , Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Ensaio de Imunoadsorção Enzimática , Neoplasias Esofágicas/mortalidade , Genótipo , Humanos , Estimativa de Kaplan-Meier , Mutação , Neovascularização Patológica/genética , Reação em Cadeia da Polimerase , Prognóstico
4.
J Gastroenterol Hepatol ; 22(12): 2303-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18031395

RESUMO

BACKGROUND AND AIM: Expression of biomarkers and probable allelic alterations were studied in esophagus tissue samples from patients with esophageal carcinoma. METHODS: A total of 116 esophagus tissue samples were obtained from 25 patients with esophagus cancer. Histological studies revealed 23 samples were adenocarcinoma and 14 samples were epidermoid carcinoma while 79 samples were non-tumor. Expression of biomarkers was determined by enzyme immunoassay, and allelic alterations on chromosome 17p were performed by polymerase chain reaction (PCR) using primers D17S513 and D17S514. RESULTS: The adenocarcinoma group exhibited an increase of matrix metalloproteinase (MMP)-1 (P < 0.0001) and sialyl Le (a) (P < 0.001) mean levels when compared with the non-tumor group. Adenocarcinoma samples from patients with more than three positive lymph nodes had lower levels of tissue-inhibitor metalloproteinase (TIMP)-1 than those with negative nodes (P < 0.0005). Positive allelic alteration was associated with high levels of MMP-1 expression (P = 0.003). Epidermoid carcinoma samples showed higher expression of MMP-1 (P < 0.0001) and TIMP-1 (P < 0.02) than non-tumor samples. Both epidermal growth factor receptor and sialyl Le (a) levels were overexpressed in tumors of patients with more than three positive lymph nodes (P < 0.005). Carcinoembryonic antigen levels were higher in tumors associated with allelic wild type group (P = 0.0001) and patients with negative lymph nodes (P < 0.05). Furthermore, variability in expression of biomarkers was observed according to sample location, and allelic alterations were also found both in tumor and in some non-tumor samples. CONCLUSION: The data suggest that overexpression of tissue biomarkers associated with allelic alterations may have potential prognostic implications with different behavior in esophagus cancer.


Assuntos
Alelos , Biomarcadores Tumorais/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Adenocarcinoma/enzimologia , Antígeno Carcinoembrionário/metabolismo , Carcinoma de Células Escamosas/enzimologia , Receptores ErbB/metabolismo , Neoplasias Esofágicas/enzimologia , Feminino , Humanos , Linfonodos/patologia , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Pessoa de Meia-Idade , Inibidor Tecidual de Metaloproteinase-1/metabolismo
5.
J Carcinog ; 6: 18, 2007 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-18045456

RESUMO

BACKGROUND: The N-Nitrosomethylurea breast cancer model induced in rats is used for the study of carcinogenesis in mammary cancer, prostate, pancreas, etc. This model is very similar to human neoplastic disease. METHODS: The present experimental study was designed to assess whether metoclopramide administration has any effect on development of MNU-induced tumours, and evaluate the treatment of goserelin acetate on PRL, TNF alpha and NO expression. NMU was administered to female Wistar rats on 2 occasions (5 mg/100 g body w/rat). PRL and TNF alpha were performed by immune-assay. Nitric Oxide by semi automated-assay and ploidy analyses by flow cytometry. RESULTS: The administration of metoclopramide made the induction time shorter and increased the incidence and average of tumours per rat. Tumours development was inhibited by a goserelin chronic administration. The ploidy of adenocarcinoma was polyploid-aneuploid type (average S = 60%). It was higher basal PRL plasma levels in rats with NMU induced tumours than in basal controls without tumour (p < 0.001). The goserelin "in bolus" administration showed maximal inhibition of plasma PRL at 90 min. Plasmatic TNF alpha expression was inhibited at 60 min and also remained inhibited in tissue homogenate post chronic treatment (P < 0.0125). Plasmatic NO expression is higher in rats with induced tumours than healthy controls (P < 0.001). In tissue homogenate NO values were inhibited at 90 min (P < 0.01), as well during chronically goserelin treatment (P < 0.005). CONCLUSION: The increase of blood PRL levels in NMU-induced rats may be an indicator of a poor prognosis of mammary cancer evolution. The metoclopramide administration accelerates tumour growth. However goserelin administration achieves regression in tumour development associated to inhibition PRL, TNF alpha and NO expression.

6.
Oncology ; 65(2): 146-51, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12931021

RESUMO

The objective of the present study was to assess the prognostic value of allelic alterations in comparison with clinical prognostic factors (age and gender, clinical stage, lymph node involvement, tissue tumour marker expression) and clinical outcomes (disease relapse and overall survival time) in colorectal cancer patients. Polymerase chain reaction was performed on the DNA of 72 colorectal samples (from 36 colorectal cancer patients) using primers D17S513 and D17S514. Carbohydrate antigen 19-9 (CA 19-9) marker was determined in tumour sections by enzyme immunoassay. Tumours were considered to exhibit allelic alterations if the microsatellite region adjacent to the p53 locus in chromosome 17 either gained or lost repeated sequences. Allelic alterations were detected in 44% of tumour samples. Patients with more than 3 involved lymph nodes had more frequent allelic alterations (p < 0.002). The allelic alteration status was compared with tumour CA 19-9 expression, which showed statistically significantly higher values within the allelic alterations group (p < 0.005). Multivariate analyses confirmed that tumours with allelic alterations had a higher probability of disease relapse (odds ratio 7.3, p = 0.01). This is the first report showing an association between allelic alteration and overexpression of a tissue tumour marker protein and established risk factors. These results could be considered useful additional prognostic information for colorectal cancer.


Assuntos
Adenocarcinoma/genética , Alelos , Biomarcadores Tumorais/genética , Cromossomos Humanos Par 17/genética , Neoplasias Colorretais/genética , Recidiva Local de Neoplasia/genética , Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Análise de Sobrevida , Regulação para Cima
7.
Tumori ; 88(2): 142-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12088255

RESUMO

AIMS AND BACKGROUND: Carcinoembryonic antigen (CEA) belongs to a family of cell surface glycoproteins. Its level in serum has a significant value for the follow-up and treatment of patients with malignancies. The aim of this study was to correlate the concentration of tumor cytosol CEA (cCEA) with tumor size, patient age and sex, clinical stage, lymph node metastases, and overall survival rate in primary non-small cell lung carcinoma (NSCLC). METHODS AND STUDY DESIGN: The cCEA levels were determined in 76 NSCLC patients by luminescence assay (LIA) and radioimmunoassay (RIA). RESULTS: A strong correlation between LIA and RIA assay results was found (r = 0.992). No correlation was observed between serum CEA and cCEA levels. Tumors smaller than 3 cm had significantly higher cCEA levels than larger tumors, but when a logistic modeling process was applied this difference was not significant (P = 0.038). Histologically well-differentiated tumors also showed a significantly higher expression of cCEA (P <0.05). In addition, patients without lymph node involvement had higher cCEA levels than patients with tumor-positive lymph nodes (P < 0.05). Univariate statistical analysis revealed that the risk of lymph node metastases was 1.8-fold higher in patients with low cCEA levels than in patients with higher levels, taking the median value as cutoff (P = 0.04, Kruskal-Wallis test). CONCLUSIONS: According to the results of our study, patients with overexpression of cCEA may have a better prognosis than those with low cCEA expression. cCEA might therefore be considered a good prognostic parameter as well as a prognostic factor independent of the traditional parameters for lymph node metastases.


Assuntos
Antígeno Carcinoembrionário/análise , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Citosol/química , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Radioimunoensaio , Fatores Sexuais , Análise de Sobrevida
8.
Am J Kidney Dis ; 40(1): 43-50, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12087560

RESUMO

BACKGROUND: Overexposure to lead may result in an increased risk for developing chronic renal failure (CRF) and hypertension. Subclinical lead poisoning is difficult to identify. Because the heme biosynthetic pathway is highly sensitive to lead, we considered the study of enzymes involved in this pathway as a method to detect an excessive body lead burden. METHODS: Main concerns in assessing the heme pathway in patients with CRF were related to aminolevulinate dehydratase (ALAD) activity. We first selected a number of patients with CRF at a predialysis stage, subsequently dividing them into two groups after the EDTA mobilization test had determined whether lead pools were expanded. The study included 24 healthy controls, 12 patients with clinical plumbism and biochemical demonstration of lead poisoning (Pb-CONT), 18 patients with CRF with no evidence of high lead storage (CRF/-), and 8 patients with CRF with high urinary excretion of lead in contrast to normal blood lead levels (CRF/+). RESULTS: As expected, symptoms of plumbism (Pb-CONT) were accompanied by an increased erythrocyte zinc-protoporphyrin-free protoporphyrin ratio and high urine coproporphyrin excretion, whereas both these values were within the normal range in all patients with CRF. CRF/- patients showed minor abnormalities of erythrocyte heme metabolism, such as low ALAD activity, both baseline and in vitro restored. The ALAD-restored ALAD ratio correlated closely with urine lead excretion; it was normal in healthy controls and CRF/- patients and significantly reduced in Pb-CONT and CRF/+ patients. CONCLUSION: The erythrocyte ALAD-restored ALAD ratio may be a useful tool to show otherwise subclinical lead poisoning in patients with CRF.


Assuntos
Eritrócitos/enzimologia , Falência Renal Crônica/enzimologia , Chumbo/sangue , Sintase do Porfobilinogênio/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Heme/metabolismo , Humanos , Falência Renal Crônica/sangue , Chumbo/urina , Intoxicação do Sistema Nervoso por Chumbo/sangue , Intoxicação do Sistema Nervoso por Chumbo/enzimologia , Masculino , Pessoa de Meia-Idade , Porfirinas/sangue
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