The Hsp90 inhibitor 17-AAG represses calcium-induced cytokeratin 1 and 10 expression in HaCaT keratinocytes

Hsp90 is essential for maintaining the activity of numerous signaling factors, and plays a key role in cellular signal transduction networks. 17-Allylamino-17-demethoxygeldanamycin (17-AAG) is an ansamycin antibiotic that binds to Hsp90 and inhibits its function. HaCaT human keratinocytes were used to investigate the cellular and molecular functions of Hsp90 in keratinocyte differentiation. Inhibition of Hsp90 by 17-AAG leads to downregulation of the differentiation markers cytokeratin 1 and cytokeratin 10 at the protein and mRNA levels.

▸ 17-Allylamino-17-demethoxygeldanamycin (17-AAG) binds to Hsp90 and inhibits its function. ▸ Inhibition of Hsp90 downregulates differentiation marker cytokeratin 1 and cytokeratin 10. ▸ Phospho-p38 was upregulated by 17-AAG in a concentration-dependent manner. ▸ Involucrin expression was increased by upregulation of p38 MAPK phosphorylation. ▸ Inhibition of Hsp90 represses cell cycle arrest.