Then IHC staining demonstrated a significant reduction in MSLN expression (p = 0.0047) and a substantial increase in CD3+CD8+ T cell infiltration (p = 0.0098) in tumor tissue after αMSLN treatment, indicating that αMSLN can effectively kill the cells with high expression of MSLN and modulate the immune microenvironment in pancreatic cancer (Figure 1I–L). This evidence concerns the gene MSLN and neoplasm.