RRM2 and cancer: Based on the THCA prognostic risk model, we screened the key molecule Ribonucleotide reductase M2 (RRM2) subunit, which has a potential pro-cancer role, to explore the functional role of RRM2 and its molecular mechanism in PTC, and to investigate the effects of RRM2 on the proliferation, apoptosis, migration invasion, cell cycle, and tumorigenicity of PTC cells in vivo.