Platinum prodrug nanoparticles inhibiting tumor recurrence and metastasis by concurrent chemoradiotherapy

Although concurrent chemoradiotherapy (CRT), as one of the most effective antineoplastic therapies in clinic, can successfully inhibit the growth of tumor cells, a risk of developing secondary tumor is still an insurmountable barrier in clinical practice.Herein, a new platinum prodrug composed of tannic acid (TA) and Pt2+ (TA-Pt) complex film was synthesized on the surface of Fe2O3 nanoparticles (NPs) with excellent stability and biocompatibility for enhanced CRT. In this system, TA-Pt complex could respond to the tumor acidic microenvironment and damage the DNA of tumor cells. Moreover, the internal iron core not only improved the effect of subsequent radiotherapy (RT), but also disrupted the iron balance in cells, inducing intracellular ferroptosis and eliminating apoptosis-resistant cells. In vitro and vivo experimental results indicated that more than 90% of tumor cells were depleted and more than 75% of the cured tumor-bearing mice evinced no recurrence or metastasis.This work offered a new idea for combining the effective chemotherapy, RT and ferroptosis therapy to enhance the curative effect of CRT and inhibit tumor recurrence and metastasis.