title: High-content image-based screening for small-molecule chaperone amplifiers in heat shock.
abstract: Heat shock proteins represent the major elements of the cellular stress response that protects cells from diseases caused by protein misfolding. Small-molecule amplifiers of heat shock proteins have shown promising results in several animal models, demonstrating the potential importance of such compounds for therapeutics. The expression of many heat shock proteins is controlled by HSF1, which forms stress granules in the nucleus when transcriptionally activated. Activation of the cellular stress also correlates with the translocation of HSP70 into nucleoli. The authors have developed an image-based, multiparametric assay to simultaneously monitor the effects of compounds on HSF1/HSP70 stress granule formation in heat-shocked Hela cells. High-content screening of the compound library was performed with a Z' of 0.62, demonstrating a highly robust assay for large-scale screening. The resulting hits showed prolonged amplification of HSP70 induction in heat-stressed cells but no effects in cells without stress. Treatment of cells with selected hits exhibited significant cytoprotection from both oxygen glucose deprivation and rotenone-induced stresses. Thus, high-content screening of HSF1/HSP70 amplifiers provides a practical opportunity for clinical therapeutics targeting protein misfolding diseases.
authors.affiliation: Department of Biology, Cytrx Corporation, San Diego, CA 92109, USA.
authors.forename: Qingyan
authors.initials: Q
authors.lastname: Au
authors.forename: Prim
authors.initials: P
authors.lastname: Kanchanastit
authors.forename: Jack R
authors.initials: JR
authors.lastname: Barber
authors.forename: Shi Chung
authors.initials: SC
authors.lastname: Ng
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
mesh_terms: D001681:Biological Assay; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000378:metabolism; D019610:Cytoprotection / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000378:metabolism; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D018869:Heat-Shock Response / Q000187:drug effects; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018832:Molecular Chaperones / Q000032:analysis*; D015203:Reproducibility of Results; D054852:Small Molecule Libraries / Q000032:analysis* / Q000494:pharmacology; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D018832:Molecular Chaperones; D054852:Small Molecule Libraries; D014157:Transcription Factors