CDK4 and cancer: At pharmacologically relevant concentrations (1–5 μM), celastrol induced 70–80% degradation of Hsp90 client proteins such as Cdk4 and Akt and triggered a robust 12-fold increase in Hsp70 expression in Panc-1 pancreatic cancer cells.46In vivo, administration of celastrol at 3 mg kg−1 resulted in more than 80% suppression of tumor metastasis, highlighting its therapeutic efficacy in aggressive cancer models.46,47