RESUMO
Expression of heparanase-1 in prostate tumors was evaluated by RT-PCR, immunoblotting, and immunohistochemistry. Malignant transformation was shown to be associated with considerable increase in the expression of heparanase-1 at both mRNA and protein levels, which correlated with the degree of metastasizing and can be used as the marker for diagnostics of the metastatic process.
Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Glucuronidase/metabolismo , Metástase Neoplásica/diagnóstico , Neoplasias da Próstata/metabolismo , Primers do DNA/genética , Humanos , Immunoblotting/métodos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
BACKGROUND: D-Glucuronyl C5-epimerase (GLCE) is a key enzyme involved in the biosynthesis of heparan sulphate proteoglycans, which has an important role in cell-cell and cell-matrix interactions and signalling. Decreased GLCE expression in human breast tumours and its anti-proliferative effects in breast cancer cells suggest that it may be a candidate tumour-suppressor gene. The aim of this study was to investigate the involvement of GLCE in lung carcinogenesis. METHODS: D-Glucuronyl C5-epimerase expression in different lung cancer cell lines was determined and the gene was ectopically re-expressed in U2020 small-cell lung cancer cells. Cellular proliferation in vitro and tumour growth in vivo were then examined. RESULTS: Ectopic re-expression of GLCE in U2020 cells did not affect cell viability but did influence morphology. Cellular proliferation in vitro and tumour formation in vivo were both suppressed. These effects were mediated via downregulation of several pro-angiogenic growth factors and their receptors, including VEGF-A, TGFB1, FGFR2, PDGF-A and PDGF-B, and TNFa and its receptors. Expression of matrix metalloproteinase2, MTA1, PLAU, TIMP3, S100A4, SERPINE1 and TWIST1 was also downregulated. CONCLUSION: The anti-tumour effects associated with ectopic GLCE re-expression suggest that it may be a potential tumour-suppressor gene and a possible target for lung cancer diagnosis and treatment.
Assuntos
Carboidratos Epimerases/metabolismo , Proliferação de Células , Carcinoma de Pequenas Células do Pulmão/enzimologia , Carcinoma de Pequenas Células do Pulmão/patologia , Animais , Western Blotting , Carboidratos Epimerases/genética , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carcinoma de Pequenas Células do Pulmão/genética , Células Tumorais CultivadasRESUMO
We studied in vitro effect of epithermal neutrons in various doses on viability of glioblastoma U87 tumor cells. Increasing the dose from 1.9 to 4.1 Sv promoted cell death. Cytofluorimetric analysis revealed no activation of apoptosis in the irradiated cells, which attested to necrotic death of the tumor cells exposed to epithermal neutron radiation.