MSLN and cancer: Deficiencies in GPI-anchor biosynthesis by downregulating MSLN expression resulted in MSLN CAR T-cell resistance in pancreatic cancer.423 Among the many regulatory enzymes, the GPI-T subunit PIG-U was pinpointed as an oncogene for bladder cancer in 2004,424 which sparked the interest of researchers to explore whether other subunits also play oncogene roles and whether they have therapeutic value for cancer treatment.