GAPDH and neoplasm: Indeed, our GPC1-specific human or murine CAR-T cells did not respond to LK2-mock or MC38-mock tumor cells (Figures 2C, D, 4C and D), although LK2-mock weakly expressed hGPC1 mRNA (hGPC1/GAPDH; 0.00059) at similar level to the normal cervix tissues (hGPC1/GAPDH; mean 0.00209 ± 0.00185, range 0.00065–0.00473) and MC38-mock expressed weak mGpc1 mRNA (mGpc1/Gapdh; 0.00532) at similar level to the evaluated various normal tissues (mGpc1/Gapdh; mean 0.02284 ± 0.01684, range 0.00341–0.06406) without detectable GPC1 protein (Figures 1, 2B and 3).