tcsc6111 KRIBB11

KRIBB11 is an inhibitor of Heat shock factor 1 (HSF1), with IC₅₀ of 1.2 μM.

IC50 & Target: IC50: 1.2 μM (HSF1)^[1]

In Vitro: KRIBB11 blocks the induction of HSF1 downstream target proteins such as HSP27 and HSP70. KRIBB11 induces growth arrest and apoptosis of HCT-116 cells. KRIBB11 inhibits HSF1-dependent recruitment of p-TEFb (positive transcription elongation factor b) to the hsp70 promoter^[1]. PARP and caspase-3 cleavage is increased in cells treated with KRIBB11. Incubating RKO with KRIBB11, shows a toxic threshold of about 10 µM, and an IC₅₀ of 20-30 µM^[2].

In Vivo: KRIBB11 (50 mg/kg, i.p.) results in a 47.4% inhibition of tumor growth in nude mice, without body weight loss^[1].