From cancer treatment to painkillers, here are the agents that may be hazardous materials today but could evolve into powerful medications tomorrow.

Rolipram is commonly known as a drug used to treat depression. It is in the family of drugs referred to as monoamine oxidase inhibitors (MAOI). It promotes the release of norepinepherine, which in term produces a better mood and an alleviation of depression symptoms. Rolipram is actually a selective phosphodiesterase inhibitor and it inhibits phosphodiesterase IV or PDE-IV, particularly the PDE-IVB subtype. Like most PDE4-inhibitors, it is an anti-inflammatory drug. Rolipram has been studied as a possible antidepressant, and it also has anti-inflammatory, immunosuppressive, and anti-tumor effects. Rolipram has also been proposed as a treatment for multiple sclerosis, as well, and recent studies show that rolipram may have antipsychotic effects.