The use of temozolomide for the treatment of malignant tumors: clinical evidence and molecular mechanisms of action.

Temozolomide (TMZ) is a monofunctional methylating agent which is spontaneously activated in aqueous solution into the dacarbazine metabolite 5-(3-methyl-1-triazeno)imidazole-4-carboxamide. This drug has been approved for the treatment of metastatic melanoma and glioblastoma multiforme, the latter in combination with radiotherapy. Furthermore, clinical trials have been performed to assess the activity of TMZ, alone or in combination, on brain metastatic solid tumors and leukaemias. This review will report clinical evidence on the use of TMZ for the treatment of different types of cancer; it also considers current knowledge on TMZ's molecular mechanisms of action of and discusses relevant patents relating to the same drug.