The levels of HMGB1 released from tumor cells after PEG-MnMOF, PTX, and PEG-MnMOF@PTX treatments were 1.76, 1.55, and 2.37 times higher than that in the control group, respectively, as illustrated in Fig. 5B. The release of ATP by dying cells also promotes the phagocytosis of APCs and augments specific antitumor effects [32,33]. Here, HMGB1 is linked to neoplasm.