Project description:We have investigated the regulation of anchorage-independent growth (AIG) by basic fibroblast growth factor (bFGF) and 12-O-tetradecanoyl phorbol-13-acetate (TPA) in JB6 mouse epidermal cells in the context of wound repair versus carcinogenesis responses. bFGF induces an unusually efficient but reversible AIG response, relative to TPA-induced AIG which is irreversible. Distinct global gene expression profiles are associated with anchorage-independent colonies arising from bFGF-stimulated JB6 cells, relative to colonies arising from fully tumorigenic JB6 cells (RT101), including genes exhibiting reciprocal regulation patterns. Thus, while TPA exposure results in commitment to an irreversible and tumorigenic AIG phenotype, the AIG response to bFGF is reversible with essentially complete restoration of normal cell cycle check point control following removal of bFGF from growth medium. These results are consistent with the physiological role of bFGF in promoting wound healing, and suggest that natural mechanisms exist to reverse transformative cellular phenotypes associated with carcinogenesis. Experiment Overall Design: To determine whether there were shared transcriptional effects between reversible and irreversible AIG, we performed global microarray analyses on colonies isolated from soft agar for both bFGF-treated JB6 cells and fully tumorigenic JB6 cells from the RT101 cell line. Gene expression changes associated with colony formation were determined by comparison to respective monolayer control cells.
Project description:We have investigated the regulation of anchorage-independent growth (AIG) by basic fibroblast growth factor (bFGF) and 12-O-tetradecanoyl phorbol-13-acetate (TPA) in JB6 mouse epidermal cells in the context of wound repair versus carcinogenesis responses. bFGF induces an unusually efficient but reversible AIG response, relative to TPA-induced AIG which is irreversible. Distinct global gene expression profiles are associated with anchorage-independent colonies arising from bFGF-stimulated JB6 cells, relative to colonies arising from fully tumorigenic JB6 cells (RT101), including genes exhibiting reciprocal regulation patterns. Thus, while TPA exposure results in commitment to an irreversible and tumorigenic AIG phenotype, the AIG response to bFGF is reversible with essentially complete restoration of normal cell cycle check point control following removal of bFGF from growth medium. These results are consistent with the physiological role of bFGF in promoting wound healing, and suggest that natural mechanisms exist to reverse transformative cellular phenotypes associated with carcinogenesis. Keywords: cell phenotype comparison
Project description:The ability of high-risk neuroblastoma to survive unfavorable growth conditions and multimodal therapy is hypothesized to result from a phenomenon known as reversible adaptive plasticity (RAP). RAP is a novel phenomenon enabling neuroblastoma cells to transition between a proliferative anchorage dependent (AD) state and a slow growing anoikis-resistant anchorage independent (AI) state. We used microarrays to investigate the global gene expression profiles in AD and AI cells, and to identify the differential expressed genes within signaling pathways contributing to the reversible adaptive plasticity between AD and AI cells.
Project description:The ability of high-risk neuroblastoma to survive unfavorable growth conditions and multimodal therapy is hypothesized to result from a phenomenon known as reversible adaptive plasticity (RAP). RAP is a novel phenomenon enabling neuroblastoma cells to transition between a proliferative anchorage dependent (AD) state and a slow growing anoikis-resistant anchorage independent (AI) state. We used microarrays to investigate the global gene expression profiles in AD and AI cells, and to identify the differential expressed genes within signaling pathways contributing to the reversible adaptive plasticity between AD and AI cells. Comparison of microarray data from AD cells (n=4 independent cultures) versus AI cells (n=4 independent cultures) were performed using Partek Genomics Suite 6.5. Differentially expressed genes with an FDR M-bM-^IM-$5% and a fold-change M-bM-^IM-%1.5 were selected for pathway analysis.