I'm listening to Stuart Schreiber make his case for diversity-oriented synthesis (DOS) as a way to interrogate biochemistry. I've written about this idea a number of times here, but I'm always glad to hear the pitch right from the source.
Schreiber's team has about 100,000 compounds from DOS now, all of which are searchable at PubChem. He says that they have about 15mg of each of them in the archives, which is a pretty solid collection. They've been trying to maximize the biochemical diversity of their screening (see here and here for examples), and they're also (as noted here) building up a collection of fragments, which he says will be used for high-concentration screening.
He's also updating some efforts with the Gates Foundation to do cell-based antimalarial screening with the DOS compounds. They have 468 compounds that they're now concentrating on, and checking these against resistant strains indicates that some of them may well be working through unusual mechanisms (others, of course, are apparently hitting the known ones). He's showing structures, and they are very DOSsy indeed - macrocycles, spiro rings, chirality all over. But since these assay are done in cells, some large hoops have already been jumped through.
He's also talking about the Broad Institutes efforts to profile small-molecule behavior in numerous tumor cell lines. Here's a new public portal site on this, and there's apparently a paper accepted at Cell on it as well. They have hundreds of cell lines, from all sorts of sources, and are testing those against an "informer set" of small-molecule probes and known drugs. They're trying to make this a collection of very selective compounds, targeting a wide variety of different targets throughout the cell. There are kinase inhibitors, epigenetic compounds, and a long list of known oncology candidates, as well as many other compounds that don't hit obvious cancer targets.
They're finding out a lot of interesting things about target ID with this set. Schreiber says that this work has made him more interested in gene expression profiles than in mutations per se. Here, he says, is an example of what he's talking about. Another example is the recent report of the natural product austocystin, which seems to be activated by CYP metabolism. The Broad platform has identified CYP2J2 as the likely candidate.
There's an awful lot of work on these slides (and an awful lot of funding is apparent, too). I think that the "Cancer Therapeutics Response Portal" mentioned above is well worth checking out - I'll be rooting through it after the meeting.