An antineoplastic agent used primarily in combination with mechlorethamine, vincristine, and prednisone (the MOPP protocol) in the treatment of Hodgkin's disease. [PubChem]
Indication
For use with other anticancer drugs for the treatment of stage III and stage IV Hodgkin's disease.
Pharmacology
Procarbazine is an antineoplastic in the class of alkylating agents and is used to treat various forms of cancer. Alkylating agents are so named because of their ability to add alkyl groups to many electronegative groups under conditions present in cells. They stop tumor growth by cross-linking guanine bases in DNA double-helix strands - directly attacking DNA. This makes the strands unable to uncoil and separate. As this is necessary in DNA replication, the cells can no longer divide. In addition, these drugs add methyl or other alkyl groups onto molecules where they do not belong which in turn inhibits their correct utilization by base pairing and causes a miscoding of DNA. Procarbazine is cell-phase specific for the S phase of cell division.
Toxicity
LD50=785 mg/kg (orally in rats)
Affected Organisms
Humans and other mammals
Biotransformation
Procarbazine is metabolized primarily in the liver and kidneys. The drug appears to be auto-oxidized to the azo derivative with the release of hydrogen peroxide. The azo derivative isomerizes to the hydrazone, and following hydrolysis splits into a benzylaldehyde derivative and methylhydrazine. The methylhydrazine is further degraded to CO2 and CH4 and possibly hydrazine, whereas the aldehyde is oxidized to N-isopropylterephthalamic acid, which is excreted in the urine.
A benzamide obtained by formal condensation of the carboxy group of 4-[(2-methylhydrazino)methyl]benzoic acid with the amino group of isopropylamine. An antineoplastic chemotherapy drug used for treatment of Hodgkin's lymphoma. Metabolism yields azo-procarbazine and hydrogen peroxide, which results in the breaking of DNA strands.