International Journal of Medical Science and Pharmaceutical Research

Hydroxamic acid (HA) and their metal complexes have attracted considerable attention because of their diverse bio-logical properties, particularly their cytotoxic and potential anticancer activities. This review provides an overview of the cytotoxic effects of selected HA, their derivatives, and their metal complexes, focusing on their activities against different cancer cell lines and their effects on normal cells. Particular attention is given to HA derivatives investi-gated in clinical or preclinical studies, including deferoxamine, vorinostat, belinostat, panobinostat, pracinostat, abexinostat, dacinostat, quisinostat, and resminostat. The reported findings indicate that several compounds exhibit significant antiproliferative effects, with activity varying according to their chemical structures, concentrations, and the cell lines investigated. Proposed mechanisms include histone deacetylase inhibition, iron chelation, reactive oxy-gen species (ROS) generation, DNA damage, cell-cycle arrest, apoptosis, and ferroptosis. The cytotoxicity of metal complexes derived from HA is also examined. Complex formation can modify biological activity and, in some cases, enhance cytotoxic effects against cancer cells. However, increased cytotoxicity does not necessarily translate into im-proved therapeutic selectivity, as certain complexes also exhibit considerable toxicity toward normal cells. Further-more, differences in experimental models and evaluation methods complicate direct comparisons between the com-pounds studied. Overall, HA and their metal complexes represent promising chemical scaffolds for anticancer research. Further investigations are required to clarify their mechanisms of action, establish their selectivity, and de-termine the relationship between chemical structure, cytotoxic activity, and biological safety.

Hydroxamic acids; Metal complexes; Cytotoxicity; Anticancer activity; Histone deacetylase inhibitors; Apoptosis; Ferroptosis.

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