This is not as simple as it sounds, because ‘a’ may not equal ‘a’. That is, some years ago when they were studying bioflavanoids for their anti-cancer effects, they discovered that for unknown reasons, while they worked in natural substances, when removed from those natural substances as pure bioflavanoids, they didn’t work.
There is a very good chance that what is having the beneficial effect comes not from the chemical being studied, but from a different chemical, or even a complex organic, like a protein, present in tiny amounts with the main chemical.
It may work in the body, but not in cancer cells in a petri dish, because it effects another part of the body that in turn acts upon the cancer cells.
This is really complicated stuff.
You mean it might stimulate the gene that stimulates a particular substance that might be envolved?