Bleomycin

Bleomycin is a mixture of the sulfate salts of basic glycopeptide antineoplastic antibiotics isolated from Streptomyces verticillus. It is used against cancer in humans and animals, not as an antimicrobial.

A relatively old drug, it is best known in the treatment of lymphomas. U.S. Food and Drug Administration approved indications include: diffuse large B-cell lymphoma, follicular B-cell lymphoma, Hodgkin's lymphoma, laryngeal carcinoma, malignant tumor of cervix, malignant tumor of head and neck, malignant testicular tumor, non-Hodgkin's lymphoma, penile carcinoma, pleural malignant effusions, squamous cell carcinoma, testicular germ cell tumor carcinoma and vulvar carcinoma.

Unlabeled uses include AIDS with Kaposi's sarcoma, mycosis fungoides, osteosarcoma of bone, ovarian germ cell tumor carcinoma, soft or connective tissue sarcoma and verruca vulgaris. It has been used for sclerotherapy in pneumothorax, pleural effusion and peritoneal effusion, replacing tetracycline for this purpose since parenteral tetracycline is no longer available in the U.S. and several other countries.

It is used in feline and canine squamous cell carcinoma.

Mechanism of action
Bleomycin sulfate forms complexes with iron that reduce molecular oxygen to superoxide and hydroxyl radicals which cause single- and double-stranded breaks in DNA; these reactive oxygen species also induce lipid peroxidation, carbohydrate oxidation, and alterations in prostaglandin synthesis and degradation.

Toxicity
While the most frequent side effects are dermatologic, treatment duration is often limited by pulmonary fibrosis.