Platinum-based antineoplastic


Platinum-based antineoplastic drugs are chemotherapeutic agents used to treat cancer. They are coordination complexes of platinum. These drugs are used to treat almost half of people receiving chemotherapy for cancer. In this form of chemotherapy, popular drugs include cisplatin, oxaliplatin, and carboplatin, but several have been proposed or are under development. Addition of platinum-based chemotherapy drugs to chemoradiation in women with early cervical cancer seems to improve survival and reduce risk of recurrence.
In total, these drugs can cause a combination of more than 40 specific side effects which include neurotoxicity, which is manifested by peripheral neuropathies including polyneuropathy.

Mechanism of action

As studied mainly on cisplatin, but presumably for other members as well, platinum-based antineoplastic agents cause crosslinking of DNA as monoadduct, interstrand crosslinks, intrastrand crosslinks or DNA protein crosslinks. Mostly they act on the adjacent N-7 position of guanine, forming a 1, 2 intrastrand crosslink. The resultant crosslinking inhibits DNA repair and/or DNA synthesis in cancer cells.
Platinum-based antineoplastic agents are sometimes described as "alkylating-like" due to similar effects as alkylating antineoplastic agents, although they do not have an alkyl group.

Examples

Strategies for improving platinum-based anticancer drugs usually involve changes in the neutral spectator ligands, which are usually nitrogenous. Changes in the nature of the anions, and changes in the oxidation state of the metal vs Pt). Nanotechnology has been explored to deliver platinum more efficiently in the case of Lipoplatin, which is introduced into the tumor sites thereby reducing the chance of toxicity.
Cisplatin was the first to be developed. Cisplatin is particularly effective against testicular cancer; the cure rate was improved from 10% to 85%.