National Cancer Institute Natural Product Library 2022 Challenge Set

The US National Cancer Institute's (NCI) Natural Product Repository is one of the world's largest, most diverse collections of natural products. It contains over 230,000 unique extracts derived from plant, marine, and microbial organisms that have been collected from biodiverse regions throughout the world. This national resource is available to the research community for the screening of extracts and the isolation of bioactive natural products. 

The NCI Program for Natural Product Discovery (NPNPD) is designed to advance natural product discovery technologies and facilitate the discovery of structurally defined, validated lead molecules ready for translation, specifically as it relates to cancer.

The Challenge Set has been created by NPNPD to be screened as a precursor to the larger natural product library as a mechanism to ensure assay conditions are amenable to natural product screening. It consists of two library plates made from 88 extracts that the NPNPD has some chemistry knowledge of, including extracts that contain nuisance and pan-assay interfering compounds such as tannins, saponins, pyridoacridines, and staurosporine. In addition, several of these extracts were cytotoxic in the NCI-60 assay.