Furthermore, when the exosomes from MFC and MFC LSD1 were incubated with PD-1 in order to block exosomal PD-L1 (MFC + CON EXO + PD-1 group & MFC + KO EXO + PD-1 group), tumor volume and tumor weight were not significantly different among MFC + CON EXO + PD-1 group, MFC + KO EXO + PD-1 group, and MFC + KO EXO group (Fig. 7a-c). Here, PDCD1 is linked to neoplasm.