A hormone called T3 makes normal mouse testicle cells produce more testosterone, which means it doesn’t just work in cancer cells—it also works in healthy ones.

Two different hormones, T3 and hCG, both make a key protein (StAR) in mouse testicle cells work harder to produce steroids, and when you use both together, they boost it even more — like two different keys that each unlock the same door, and using both at once opens it wider.