RESUMO
We have previously reported that angiopoietin-1 was correlated with pulmonary fibrosis. Here, we investigated the serum levels of angiopoietin-1 in patients with malignant peritoneal mesothelioma, which originate from mesenchymal cells similar to lung fibroblasts. We showed that patients with peritoneal mesothelioma had significantly higher serum levels of angiopoietin-1 in comparison with a population with a history of asbestos exposure without peritoneal mesothelioma, and the Kaplan-Meier method revealed a significant correlation between serum angiopoietin-1 levels and survival. This is the first report about the relationship between angiopoietin-1 and peritoneal mesothelioma.
Assuntos
Angiopoietina-1/sangue , Mesotelioma/sangue , Mesotelioma/mortalidade , Neoplasias Peritoneais/sangue , Neoplasias Peritoneais/mortalidade , Amianto/toxicidade , Asbestose/sangue , Exposição Ambiental , Feminino , Humanos , Masculino , Mesotelioma/epidemiologia , Pessoa de Meia-Idade , Neoplasias Peritoneais/epidemiologia , Fibrose Pulmonar/complicações , SobrevidaRESUMO
BACKGROUND/AIMS: Extracellular adenosine induces apoptosis in a variety of cancer cells via diverse signaling pathways. The present study investigated the mechanism underlying adenosine-induced apoptosis in A549 human lung cancer cells. METHODS: MTT assay, TUNEL staining, flow cytometry using propidium iodide and annexin V-FITC, real-time RTPCR, Western blotting, monitoring of mitochondrial membrane potentials, and assay of caspase-3, -8, and -9 activities were carried out in A549 cells, and the siRNA to silence the A(3) adenosine receptor-targeted gene was constructed. RESULTS: Extracellular adenosine induces A549 cell apoptosis in a concentration (0.01-10 mM)-dependent manner, and the effect was inhibited by the A3 adenosine receptor inhibitor MRS1191 or knocking-down A(3) adenosine receptor. Like adenosine, the A(3) adenosine receptor agonist 2-Cl-IB-MECA also induced A549 cell apoptosis. Adenosine increased expression of mRNAs for Puma, Bax, and Bad, disrupted mitochondrial membrane potentials, and activated caspase-3 and -9 in A549 cells, and those adenosine effects were also suppressed by knocking-down A3 adenosine receptor. CONCLUSION: Adenosine induces A549 cell apoptosis by upregulating expression of Bax, Bad, and Puma, to disrupt mitochondrial membrane potentials and to activate caspase-9 followed by the effector caspase-3, via A(3) adenosine receptor.