An increasing resistance of mammalian tumor cells to chemotherapy along with the severe side
effects of commonly used cytostatics has raised the urgency in the search for new anti-cancer agents. Several
drugs originally approved for indications other than cancer treatment have recently been found to have a
cytostatic effect on cancer cells. These drugs could be expediently repurposed as anti-cancer agents, since
they have already been tested for toxicity in humans and animals. The groups of newly recognized potential cytostatics
discussed in this review include benzimidazole anthelmintics (albendazole, mebendazole, flubendazole), anti-hypertensive
drugs (doxazosin, propranolol), psychopharmaceuticals (chlorpromazine, clomipramine) and antidiabetic drugs (metformin,
pioglitazone). All these drugs have a definite potential to be used especially in combinations with other cytostatics; the
chemotherapy targeting of multiple sites now represents a promising approach in cancer treatment. The present review
summarizes recent information about the anti-cancer effects of selected drugs commonly used for other medical
indications. Our aim is not to collect all the reported results, but to present an overview of various possibilities.
Advantages, disadvantages and further perspectives regarding individual drugs are discussed and evaluated.