RESUMEN
BACKGROUND: Cyclin-dependent kinases (CDKs) are involved in the regulation of the cell cycle and the growth of tumor cells. In this study, we investigated the antitumor effect and differentially expressed genes (DEGs) in head and neck cancer cells treated by a novel CDK inhibitor, 2-[1,1'-biphenyl]- 4-yl-N-[5-(1,1-dioxo-1lambda(6)-isothiazolidin-2-yl)-1H-indazol-3-yl] acetamide (BAI). METHODS: Cell growth was measured by XTT assay. Cell cycle and apoptosis were determined using flow cytometry. GeneFishing PCR was utilized to identify DEGs. Protein expression was analyzed by Western blot. RESULTS: Exposure to BAI of 2 different head and neck cancer cell lines, AMC-HN4 and AMC-HN6, induced apoptosis in association with growth inhibition, cell cycle arrest, caspase-3 activation and cytochrome c release. Significantly, data from GeneFishing PCR experiments demonstrated 10 DEGs in AMC-HN6 cells treated with BAI. Some of these DEGs turned out to encode proteins with functions related to key cellular processes. CONCLUSIONS: These results indicate that BAI has strong anticancer activities on head and neck cancer cells, and the DEGs induced by BAI may become involved in BAI-induced cancer cell death.
Asunto(s)
Antineoplásicos/farmacología , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de Cabeza y Cuello/genética , Indazoles/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Tiazolidinas/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Citocromos c/metabolismo , Genes Relacionados con las Neoplasias/efectos de los fármacos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/metabolismo , Humanos , Inhibidores de Proteínas Quinasas/química , Fosfolipasas de Tipo C/metabolismoRESUMEN
OBJECTIVES: The melanoma antigen gene (MAGE) and synovial sarcoma on X chromosome (SSX) gene families are silent in most normal adult tissues, but are expressed in a variety of malignant lesions. Therefore, detection of MAGE and SSX transcription may be useful for the diagnosis of head and neck cancers. The aim of this study is to detect MAGE and SSX gene transcripts of head and neck cancers using the MAGE 1-6 assay and the SSX 1-9 assay. METHODS: The transcripts of MAGE 1-6 and SSX 1-9 genes were detected by the MAGE 1-6 assay and the SSX 1-9 assay respectively, in cancer cell lines, cancer tissue, and induced sputum specimens from head and neck cancer patients. RESULTS: The transcripts of MAGE 1-6 and SSX 1-9 genes were detected in 82.8% and 75.9% of head and neck cancer tissues (N=29) respectively, and 96.6% of cancer tissues expressed at least one of MAGE 1-6 or SSX 1-9 genes. In the induced sputum of head and neck cancer patients (N=18), the transcripts of MAGE 1-6 and SSX 1-9 genes were detected in 72.2% and 77.8%, respectively, and 94.4% of the sputum specimens were positive for either the MAGE 1-6 or the SSX 1-9 assay. CONCLUSION: These results suggest that the combination of MAGE 1-6 and SSX 1-9 assays may be useful in the diagnosis of head and neck cancer.
RESUMEN
A microbial secondary metabolite, arisostatins A (As-A), was originally discovered as a substance carrying the antibiotic activity against Gram-positive bacteria and shown to possess potent anti-tumor properties. The mechanism by which arisostatins A initiates apoptosis remains poorly understood. In the present report we investigated the effect of arisostatins A on activation of the apoptotic pathway in HN-4 cells. Arisostatins A was shown to be responsible for the inhibition of HN-4 cell growth by inducing apoptosis. Treatment with 4 microM arisostatins A for 24h produced morphological features of apoptosis and DNA fragmentation in HN-4 cells. Arisostatins A caused dose-dependent apoptosis and DNA fragmentation of HN-4 cells used as a model. Treatment with caspase inhibitor significantly reduced the arisostatins A-induced caspase 3 activation. In addition, arisostatins A-induced apoptosis was associated with the generation of reactive oxygen species (ROS), which was prevented by an antioxidant NAC (N-acetyl-cysteine). These data indicate that cytotoxic effect of arisostatins A on HN-4 cells is attributable to the induced apoptosis and that arisostatins A-induced apoptosis is mediated by caspase-3 activation pathway, loss of mitochondrial transmembrane potential (DeltaPsi(m)), and release of cytochrome c into cytosol.