PCNA and neoplasm: Compared with the untreated control group, the PFC@O2 treatment group had significantly reduced tumor volumes and numbers (Figure 3A–C), tumor tissue HE is shown in Figure 3D, and IHC showed that the expression of PCNA in the PFC@O2 treatment group was significantly reduced (Figure 3E,F), which indicated that PFC@O2 could significantly inhibit the growth of OSCC.