Cis-platinum (cisplatin), carboplatin and oxaliplatin are all used as cytotoxic therapy. They cause cross links of DNA bases and in this respect are similar to the alkylating agents.
Mechanism of Action
These molecules cause cross links within the DNA molecule which are difficult to repair due to the presence of the platinum adduct. They therefore cause cell death in cells with significant levels of damage.
Interaction with Radiotherapy
These drugs are potent radiosensitisers. The effect is thought to be impairment of radiation induced DNA damage repair, particularly of single strand breaks, due to the presence of platinum adducts. Radiation may also increase intracellular concentrations of cisplatin.
Uses
These drugs are used widely in cancer treatment. Cisplatin, along with 5-FU, is one of the more common agents administered concurrently with radiotherapy due to its effectiveness as a radiosensitiser.
Toxicity
Myelosuppression is common as is alopecia. Cisplatin and oxaliplatin are particularly renowned for causing otoxicity, peripheral neuropathy, and renal impairment. This is not shared by carboplatin.
