RESUMO
In the present study, we examined whether caspases and their upstream regulators are involved in rotenone-induced cytotoxicity. Rotenone significantly inhibited the proliferation of oral cancer cell lines in a dose-dependent manner compared to normal oral mucosal fibroblasts. Flow cytometric analysis of DNA content showed that rotenone treatment induced apoptosis following G2/M arrest. Western blotting showed activation of both the caspase-8 and caspase-9 pathways, which differed from previous studies conducted in other cell types. Furthermore, p53 protein and its downstream pro-apoptotic target, Bax, were induced in SAS cells after treatment with rotenone. Rotenone-induced apoptosis was inhibited by antioxidants (glutathione, N-acetylcysteine, and tiron). In conclusion, our results demonstrate significant involvement of caspases and their upstream regulators in rotenone-induced cytotoxicity.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Caspase 8/metabolismo , Caspase 9/metabolismo , Neoplasias Bucais/metabolismo , Rotenona/farmacologia , Antineoplásicos/antagonistas & inibidores , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Caspase 8/análise , Caspase 9/análise , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Fase G2/efeitos dos fármacos , Humanos , Neoplasias Bucais/enzimologia , Rotenona/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Lung cancer is the most prevalent malignant tumor in the world. Metastasis of the disease causes death in lung cancer patients. Recent study has shown that multiple cascades of gene defects occur in lung cancer. In this report, we established a novel H1299/EGFP tumor model to determine whether H1299 transfected with the enhanced green fluorescent protein (EGFP) gene in vitro and xenotransplanted into SCID mouse lung would permit the detection of lung cancer micrometastasis in vivo. We demonstrated that EGFP-transduced H1299 cells maintained stable high-level EGFP expressions during their growth in vivo. EGFP fluorescence clearly demarcated the primary seeding place and readily allowed for the visualization of distant micrometastasis and local invasion at the single-cell level. Small metastatic and locally invasive foci, including those immediately adjacent to the tumor's leading invasive edge, were almost undetectable by routine hematoxylin and eosin staining and immunohistochemistry. The GFP tagged lung cancer model is superior for the detection and study of physiologically relevant patterns of lung cancer invasion and metastasis in vivo.