Evaluation of micro-parallel liquid chromatography as a method for HTS-coupled actives verification

Novel brd4 inhibitors with a unique scaffold exhibit antitumor effects

Since bromodomain containing 4 (brd4) has been considered as a prominent cancer target, numerous attempts have been made to develop potent brd4 bromodomain inhibitors. The present study provided a novel chemical scaffold which inhibited brd4 activity. Mid-throughput screening against brd4 bromodomain was performed using alpha-screen and homogeneous time-resolved fluorescence assays. Furthermore, cell cytotoxicity and xenograft assays were performed to examine if the compound was effective both in vitro and in vivo. As a result, it was revealed that compounds having naphthalene-1,4-dione scaffold inhibited the binding of bromodomain to acetylated histone. The compounds with naphthalene-1,4-dione had cytotoxic effects against the Ty82 cell line, a NUT midline carcinoma cell line, whose proliferation is dependent on brd4 activity. A10, one of the compounds with naphthalene-1,4-dione scaffold, also exhibited tumor growth inhibition effects in the xenograft assay. In addition, the compounds exhibited cytotoxic effects against gastric cancer cell lines which were resistant to I-BET-762, a BET bromodomain inhibitor. In conclusion, the novel scaffold to suppress brd4 activity was effective against cancer cells both in vitro and in vivo.

The essential roles of chemistry in high-throughput screening triage

It is increasingly clear that academic high-throughput screening (HTS) and virtual HTS triage suffers from a lack of scientists trained in the art and science of early drug discovery chemistry. Many recent publications report the discovery of compounds by screening that are most likely artifacts or promiscuous bioactive compounds, and these results are not placed into the context of previous studies. For HTS to be most successful, it is our contention that there must exist an early partnership between biologists and medicinal chemists. Their combined skill sets are necessary to design robust assays and efficient workflows that will weed out assay artifacts, false positives, promiscuous bioactive compounds and intractable screening hits, efforts that ultimately give projects a better chance at identifying truly useful chemical matter. Expertise in medicinal chemistry, cheminformatics and purification sciences (analytical chemistry) can enhance the post-HTS triage process by quickly removing these problematic chemotypes from consideration, while simultaneously prioritizing the more promising chemical matter for follow-up testing. It is only when biologists and chemists collaborate effectively that HTS can manifest its full promise.