A chemical proteomics approach reveals Hsp27 as a target for proapoptotic clerodane diterpenes.
Clerodane diterpenoids are a class of naturally occurring molecules widely distributed in the Lamiaceae family. Neo-clerodane diterpenoids from Salvia ssp were recently described as compounds inhibiting the proliferation of human cancer cell lines. To gain new insights into molecular mechanism(s) underlying the antitumor potential of this class of compounds, we used a chemical proteomics approach to analyse the cellular interactome of hardwickiic acid (HAA) selected as a representative molecule. HAA was linked to an opportune 1,1'-carbonyldiimidazole modified by 1,12-dodecanediamine and then immobilized on a matrix support. The modified beads were then used as bait for fishing the potential partners of HAA in a U937 cell lysate. We identified heat shock protein 27 (Hsp27), an ATP-independent antiapoptotic chaperone characterized for its tumorigenic and metastatic properties and now referenced as a major therapeutic target in many types of cancer, as a major HAA partner. Here, we also report the study of HAA-Hsp27 interaction by means of a panel of chemical and biological approaches, including surface plasmon resonance measurements limited proteolysis, and biochemical assays. Our data suggest that HAA could provide a potential tool to develop strategies for the discovery of Hsp27 chemical inhibitors.
Dipartimento di Scienze Farmaceutiche, Università di Pisa, via Bonanno 33, 56126 Pisa, Italy.
Laura
L
Faiella
Fabrizio Dal
FD
Piaz
Angela
A
Bisio
Alessandra
A
Tosco
Nunziatina
N
De Tommasi
D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001665:Binding Sites; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D017077:Culture Media, Conditioned / Q000737:chemistry; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D045785:Diterpenes, Clerodane / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D055551:HSP27 Heat-Shock Proteins / Q000737:chemistry* / Q000378:metabolism; D006360:Heat-Shock Proteins; D006801:Humans; D007093:Imidazoles / Q000737:chemistry; D008863:Microspheres; D018832:Molecular Chaperones; D010936:Plant Extracts / Q000737:chemistry*; D011485:Protein Binding; D059748:Proteolysis; D040901:Proteomics / Q000379:methods; D027544:Salvia / Q000737:chemistry*; D020349:Surface Plasmon Resonance
D000972:Antineoplastic Agents, Phytogenic; D017077:Culture Media, Conditioned; D004224:Diterpenes; D045785:Diterpenes, Clerodane; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D007093:Imidazoles; D018832:Molecular Chaperones; D010936:Plant Extracts; C074343:hardwickic acid; C006900:N,N-carbonyldiimidazole