Although CEACAM1 was not proven highly expressed in the high mRNAsi score group, or closely correlated with ICS and MTS (Fig. 2B, E, F), it can be inferred that CEACAM1+ CEACAM5+ cancer cells may be a small subpopulation of CEACAM5+ pancreatic cancer stem cells endowed with an elevated immune privilege. Here, CEACAM1 is linked to cancer.