Xu et al. constructed a manganese porphyrin-based metal–organic framework (Mn-MOF), and found that it could not only catalyze the production of O2 from H2O2 to alleviate tumor hypoxia, but also reduce the expression of GSH and GPX4, leading to better antitumor effects in H22 and 4T1 tumor-bearing mice [16]. Here, GPX4 is linked to neoplasm.