Initially it will use human data. It will find the majority of human research to be meaningless &/or fraudulent (90%+). It will have to identify the good research and build on that. Cures will probably result from cross-discipline thinking that most humans are incapable of. AI will also be able to run millions of simultaneous simulations to save time. Rather than doing a 4 year study costing $2M and finding nothing, they'll do simulations that cost next to nothing.
When they do eventually find cures, the knowledge will come from wherever it is now. ie. the pink mist.