Heat Shock Protein Inhibitor II

Heat shock protein (Hsp) inhibitor II is the active form of Hsp inhibitor I (Item No. 15395) and a benzylidene lactam compound that prevents the synthesis of inducible Hsps, such as Hsp105, Hsp72, and Hsp40. Hsp inhibitor II decreases Hsp72 synthesis in vivo and reduces thermotolerance of tumors in SCC VII tumor-containing mice.¹ At 100 µM, it inhibits the development of thermotolerance in COLO 320 DM cells.² Inhibition of Hsp70 with Hsp inhibitor II in combination with amphotericin B (AmB; Item No. 11636) increases susceptibility of AmB-susceptible (MICs = 0.058 versus 0.27 µg/ml for combined and AmB alone, respectively) and AmB-resistant (MICs = 21.33 versus >32 µg/ml for combined and AmB alone, respectively) strains of A. fumigatus.³

WARNING This product is not for human or veterinary use.

1. Koishi, M., Yokota, S., Mae, T., et al. The effects of KNK437, a novel inhibitor of heat shock protein synthesis, on the acquisition of thermotolerance in a murine transplantable tumor in vivo. Clin. Cancer Res. 7(1), 215-219 (2001).

2. Yokota, S., Kitahara, M., and Nagata, K. Benzylidene lactam compound, KNK437, a novel inhibitor of acquisition of thermotolerance and heat shock protein induction in human colon carcinoma cells. Cancer Res. 60(11), 2942-2948 (2000).

3. Blatzer, M., Blum, G., Jukic, E., et al. Blocking Hsp70 enhances the efficiency of amphotericin B treatment against resistant Aspergillus terreus strains. Antimicrob. Agents and Chemother. 59(7), 3778-3788 (2015).