I read a lot of medical research papers and I'd say about 1 in 10 is about cancer. They usually go something like this: We found this receptor on a cancer cell and it caused it to grow or shrink. We therefore propose making a drug to inhibit or act as an agonist for this receptor site which also affects an enormous amounts of completely un-releated stuff around the body in order to fight cancer.

Truth is, they may have just gotten a funny little mutant of a cancer cell that happens to heavily express this one receptor as part of its unique mutated biology. For all we know a lot of cancer research has been about exploring the peculiarities of the genome of Henrietta Lacks.