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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Actin Cytoskeleton, Animals, Breast Neoplasms, Cell Line, Tumor, Cell Surface Extensions, Down-Regulation, Female, Focal Adhesions, Humans, Immediate-Early Proteins, Mice, Mice, Knockout, Neoplasm Invasiveness, Reactive Oxygen Species, Tumor Suppressor Proteins.
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Does tIS21/BTG2 inhibit invadopodia formation by downregulating reactive oxygen species level in MDA-MB-231 cells? Context: Invasion of cancer cells depends on the proteolytic degradation of extracellular matrix regulated by actin-driven membrane protrusions, called invadopodia. However, the mechanisms underlying invadopodia formation in cancer cells remain largely unknown. By employing adenoviral transduction of breast cancer cells with either β-galactosidase (Ad-LacZ) or TIS21(/BTG2/Pc3) (Ad-TIS21) gene, the regulation of invadopodia formation was investigated. Invasion activity was examined by invadopodia assay and Matrigel assay. Intracellular reactive oxygen species (ROS) was monitored by FACS-based analysis. Here, we observed that TIS21 suppressed invadopodia formation as well as invasion activity along with F-actin remodeling. The inhibition of TIS21-mediated invadopodia formation was accompanied with attenuation of ROS generation in the TIS21 expressers, indicating that TIS21-mediated inhibition of ROS plays a critical role for invadopodia formation by regulating actin-associated protein remodeling. This was further confirmed in the TIS21(-/-)MEF cells.
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This is the first report to provide insight into invasion signals regulated by tumor suppressor, TIS21(/BTG2/Pc3) gene, in the intractable breast cancer cells. Final Decision: yes