BIOLOGICAL SIGNIFICANCE

Bleomycin is a glycosylated linear nonribosomal peptide antibiotic produced by the bacterium Streptomyces verticillus. Bleomycin refers to a family of structurally related compounds. When used as an anti-cancer agent, the chemotherapeutical forms are primarily bleomycin A2 and B2.

CLINICAL USE

The drug is used in the treatment of Hodgkin lymphoma, squamous cell carcinomas, and testicular cancer,

Pleurodesis as well as warts, Bladder ,Cancer of the lymph nodes (lymphoma), Escape of fluid into a body cavity from a tumor that is invading tissue (malignant effusions),

Lung cancer, Metastatic cancerous melanoma, Squamous cell carcinoma - a type of skin cancer, Testicular cancer ,Thyroid cancer.

MODE OF ACTION

Bleomycin acts by induction of DNA strand breaks. Some studies suggest that bleomycin also inhibits incorporation of thymidine into DNA strands. DNA cleavage by bleomycin depends on oxygen and metal ions, at least in vitro. It is believed that bleomycin chelates metal ions (primarily iron) producing a pseudo enzyme that reacts with oxygen to produce super oxide and hydroxide free radicals that cleave DNA. In addition, these complexes also mediate lipid per oxidation and oxidation of other cellular molecules.

STRUCTURE: