oxidase (Nox) isozymes are implicated in the diseases associated with oxidative
stress, and search of their selective inhibitors has been a focus of attention.
By screening microbial metabolites, Nakano and colleagues identified a novel
Nox1 inhibitor (NOS31) produced from actinomyces. NOS31 inhibited Nox1-mediated
hydrogen peroxide production with high Nox1 selectivity and suppressed
proliferation of colon and gastric cancer cells that up-regulate Nox1. Thus,
NOS31 may have the therapeutic potential for treating cancer involving the
over-activation of Nox1.