Role of semisynthetic flavonoids on cytotoxic chemotherapy—Dual benefit to cancer patients?

Abstract Despite advances in chemotherapy, the prognosis of cancer patients with advanced-stage disease is still poor indicating the high need for novel and more efficient therapeutic strategies. Based on the currently available data, the inclusion of certain semisynthetic flavonoids in chemotherapeutic regimens might be beneficial rather than harmful, potentiating anticancer mechanisms of cytotoxic drugs in malignant cells, while protecting normal healthy cells from chemotherapy-induced oxidative damage. There are several factors other than radical scavenging ability of semisynthetic flavonoids determining their interactions with chemotherapeutic drugs, including sequence of administration and schedule of treatments, molecular features of malignant cells, as well as characteristics of tumor microenvironment. Selective antioxidant action of semisynthetic flavonoids alleviating drug effects in healthy cells can proceed from differential activities of chemotherapeutics in normal versus malignant cells. It is hoped that the combined treatment of antineoplastic agents with semisynthetic flavonoids might be a solution for a better therapy in the future.