We performed Immunohistochemistry (IHC) analysis on adjacent non‐cancerous and cancerous tissues (n = 60), serous cystadenomas (n = 33) and solid pseudopapillary neoplasms (SPN, n = 26), and the expression of TRIM21 in PC tumor tissues is higher than that in the other three types of tissues (Figure 1F,G, Figure S1D, Supporting Information). Here, TRIM21 is linked to neoplasm.