cisplatin + cyclophosphamide + etoposide + lomustine + methotrexate + thiotepa + vincristine

This is a multi-agent chemotherapy regimen composed of seven cytotoxic drugs: cisplatin, cyclophosphamide, etoposide, lomustine, methotrexate, thiotepa, and vincristine. Each component has a distinct mechanism of action targeting rapidly dividing cancer cells through various pathways: - Cisplatin is a platinum-based compound that forms DNA crosslinks and inhibits DNA synthesis. - Cyclophosphamide is an alkylating agent that interferes with DNA replication by forming covalent bonds with DNA. - Etoposide inhibits topoisomerase II, leading to double-strand breaks in DNA. - Lomustine (CCNU) is a nitrosourea alkylating agent causing interstrand crosslinks in DNA and RNA. - Methotrexate inhibits dihydrofolate reductase (DHFR), blocking folic acid metabolism required for nucleotide synthesis. - Thiotepa is an alkylating agent that crosslinks DNA strands to prevent cell division. - Vincristine binds tubulin and disrupts microtubule formation during mitosis. This combination may be used in the treatment of certain aggressive or refractory cancers where multi-drug regimens are indicated. The specific indications depend on clinical protocols but can include some pediatric brain tumors or relapsed/refractory malignancies. The regimen leverages multiple mechanisms to maximize cytotoxicity against tumor cells while attempting to minimize resistance.