vincristine + doxorubicin + hydroxyurea

This is a combination chemotherapy regimen consisting of three antineoplastic agents—vincristine, doxorubicin, and hydroxyurea. Each drug has a distinct mechanism of action targeting rapidly dividing cancer cells: - **Vincristine** is a vinca alkaloid that inhibits microtubule formation in mitotic spindle fibers, arresting cell division at metaphase. It is commonly used in the treatment of leukemias and lymphomas[1]. - **Doxorubicin** is an anthracycline antibiotic that intercalates DNA strands and inhibits topoisomerase II, leading to DNA damage and apoptosis. - **Hydroxyurea** is an antimetabolite that inhibits ribonucleotide reductase, thereby blocking DNA synthesis during the S-phase of the cell cycle[7]. This combination may be used for high-risk or refractory hematologic malignancies or as part of experimental regimens for certain cancers. The specific use depends on disease context; it has been included in multi-agent regimens for conditions such as leukemia and gestational trophoblastic neoplasia[6].