"For many people, tobacco represents a death sentence -- inflicting nicotine addiction, lung cancer and other ills. But for millions of women in the developing world at risk for cervical cancer, tobacco could eventually be a lifesaver.
University researchers are working on genetically engineering tobacco plants to produce an experimental vaccine against the human papillomavirus, or HPV, which can lead to cervical cancer"

Ironic, isn't it?

No Smoke: Tobacco Used in Vaccine