Bleomycin

Bleomycin is a pharmaceutical used to treat certain types of cancer, usually along with other pharmaceuticals. It is derived from bacteria. It works by breaking up strands of DNA. It is used in cases of lymphoma, testicular cancer, ovarian cancer and cervical cancer. 
Because Bleomycin reacts with oxygen, its main side effect is pulmonary fibrosis. As such, although it also has antibiotic properties, it is rarely used for this purpose. 
Bleomycin at Wikipedia
Category:Pharmaceuticals