The class IIb HDAC6 inhibitor, tubastatin A, showed enhanced heat shock-induced Hsp70, alone and when combined with arimoclomol, and increased neuronal, but not non-neuronal, Hsp70 induced by the HSP90 inhibitor, NXD30001, yet it was ineffective in the ALS models with respect to Hsp70 induction. The gene discussed is HDAC6; the disease is amyotrophic lateral sclerosis.