Treatment with Sfn‐containing nanoformulations (including CS, CIS, and CISE NPs) obviously elicited CRT exposure on the surface of tumor cells and reduced extracellular release of HMGB1 compared to treatment with PBS or Sfn alone (Figure 3K,L and Figure S8A,B, Supporting Information). This evidence concerns the gene HMGB1 and in situ carcinoma.