International journal of cancer. Journal international du cancer
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Sarcomatoid carcinomas (SC) of the lung are uncommon malignant tumors composed of carcinomatous and sarcomatous cell components and characterized by a more aggressive outcome than other histological subtypes of nonsmall cell lung cancer (NSCLC). Although epidermal growth factor receptor (EGFR)-targeted therapies have emerged as a promising therapeutic approach in patients with advanced typical NSCLC such as adenocarcinoma, the potential clinical activity of these drugs in lung SC is still unknown. To investigate this point, we have analyzed the status of 4 EGFR pathways biomarkers in a series of lung SC. ⋯ KRAS mutations were found in 8 patients (38%; Gly12Cys in 6 cases and Gly12Val in 2 cases). The consistent EGFR protein overexpression and the high rate of KRAS mutation may contribute to the poorer outcome of lung SC in comparison with typical NSCLC. The rare incidence of increased EGFR gene copy number, the lack of EGFR mutation and the high rate of KRAS mutation observed in our series also suggest that most patients with lung SC are not likely to benefit from anti-EGFR therapies.
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OX40 costimulation can abrogate Foxp3+ regulatory T cell-mediated suppression of antitumor immunity.
Regulatory T cells (Tregs) play an important role in maintaining immunological tolerance that is one of the main obstacles to overcome for improving antitumor immunity. Recently, the Treg has been shown to constitutively express OX40 (CD134), which is a member of the TNF-receptor family that is transiently expressed on effector T cells after TCR triggering, and through which the signal enhances effector T-cell proliferation and memory T-cell development. However, little is known about the role of OX40 costimulation to Tregs in tumor immunology. ⋯ Interestingly, Tregs minimally suppressed the proliferation or the cytokine secretion of Ag-specific CD8(+) T cells after Ag-restimulation. Furthermore, Tregs suppressive function to the antitumor effect was reversed by OX40 costimulation in vivo. Our data indicate that, in addition to controlling effector T-cell function, OX40 costimulation directly controls Treg-mediated suppression in tumor immunity.
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Coffee, tea and maté may cause esophageal cancer (EC) by causing thermal injury to the esophageal mucosa. If so, the risk of EC attributable to thermal injury could be large in populations in which these beverages are commonly consumed. In addition, these drinks may cause or prevent EC via their chemical constituents. ⋯ For other hot foods and drinks, over half of the studies showed statistically significant increased risks of EC associated with higher temperature of intake. Overall, the available results strongly suggest that high-temperature beverage drinking increases the risk of EC. Future studies will require standardized strategies that allow for combining data and results should be reported by histological subtypes of EC.
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The current study was designed to critically evaluate the notion that cancer stem cell (CSC)-like cells constitute a subpopulation of cells within experimental gliomas. Virtually all cells within the N29 and N32 rat glioma models homogenously expressed CD133, the stem/progenitor marker nestin as well as the neural lineage markers glial fibrillary acidic protein, betaIII-tubulin, and CNPase in vitro. The phenotype was largely retained on exposure to conditions promoting differentiation in vitro and after intracranial implantation of tumor cells into syngeneic hosts. ⋯ Single N29 and N32 tumor cells invariably formed clones in vitro, and intracerebral inoculation of as few as 10 adherently growing N29 and N32 tumor cells, respectively, gave rise to a tumor. These results provide an alternative view on CSC-like cells in glioma models: sphere-formation is not a prerequisite for accumulation of tumorigenic cells, and CSC-like cells do not reside within a rare subpopulation of cells in these glioma models. N29 and N32 gliomas may accordingly be used for the development of treatment strategies directed specifically against a practically pure population of brain tumor-initiating CSC-like cells.