title: Adenomatous polyposis coli mutants dominantly activate Hsf1-dependent cell stress pathways through inhibition of microtubule dynamics.
abstract: Cancer cells up-regulate cell stress pathways, including the protein chaperone Hsp90. Increases in Hsp90 are believed "buffer" mutant protein activities necessary for cancer phenotypes. Activation of the cell stress pathway also alters the transcriptional landscape of cells in ways that are critical for cancer progression. However, it is unclear when and how the cell stress pathway is de-regulated during cancer progression. Here we report that mutations in adenomatous polyposis coli (APC) found in colorectal cancer activate cell stress pathways in mouse intestinal crypt cells, prior to loss of heterozygosity at APC or to the appearance of canonical intestinal cancer markers. Hsp90 levels are elevated in normal APC heterozygote crypt cells and further elevated in non-cancer cells adjacent to dysplasias, suggesting that the Hsp90 stress pathway marks the "cancer-field" effect. Expression of mutant APC in normal human epithelial cells is sufficient to activate a cell stress pathway via perturbations in microtubule dynamics. Inhibition of microtubule dynamics is sufficient to activate an Hsf1-dependent increase in gene transcription and protein levels. We suggest that the early activation of this Hsf1 dependent cell stress pathway by mono-allelic mutations in APC can affect cell programming in a way that contributes to cancer onset.
authors: Department of Cell and Molecular Biology, University of California, Davis, CA, USA.
authors: Alexander E
authors: AE
authors: Davies
authors: Department of Cell and Molecular Biology, University of California, Davis, CA, USA.
authors: Kaitlyn
authors: K
authors: Kortright
authors: Department of Cell and Molecular Biology, University of California, Davis, CA, USA.
authors: Kenneth B
authors: KB
authors: Kaplan
mesh_terms: D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D017491:Genes, APC; D020022:Genetic Predisposition to Disease; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D000076249:Heat Shock Transcription Factors; D006579:Heterozygote; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D019656:Loss of Heterozygosity; D008822:Mice, Transgenic; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D009154:Mutation; D010641:Phenotype; D034622:RNA Interference; D055213:Retinal Pigment Epithelium / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction; D013312:Stress, Physiological / Q000187:drug effects; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection; D050257:Tubulin Modulators / Q000494:pharmacology
chemical_list: D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D018841:HSP90 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; C490017:Hsf1 protein, mouse; D014157:Transcription Factors; D050257:Tubulin Modulators
keywords: Hsp90; adenomatous polyposis coli; cancer field effect; cell stress; microtubules