Transitional Metal-Based Noncatalytic Medicine for Tumor Therapy

Nanocatalytic medicine has been emerging as a highly promising strategy for cancer therapeutics since it enables tumor suppression by in situ generating toxic agents within tumors through catalytic reactions without using conventional highly toxic and nonselective chemodrugs. In the last several years, a number of nanocatalytic medicines have been used to steer catalytic reactions in endogenous or exogenous stimuli-activated cancer therapy, such as chemodynamic therapy, photodynamic therapy, and sonodynamic therapy. In particular, transitional metal-based nanocatalytic medicines with excellent catalytic activity and selectivity show significant clinical potentials, and significant progress has been achieved very recently. In this review, three types of typical transitional metal (Fe, Mn, and Cu)-based nanocatalytic medicines are summarized, followed by detailed discussions on their catalytic mechanisms. Of note, the obstacles and challenges that will be encountered in the design and further clinical conversion of transitional metal-based nanocatalytic medicine in the future are also outlooked.