(A) [³H]-Gly-Sar uptake showing functional uptake of the dipeptide in normal pancreatic cell lines hTERT-HPNE and 10 PDAC cell lines at pH 5.5 and 7.5. (B) [³H]-Gly-Sar kinetics in the presence of increasing concentration of unlabeled Gly-Sar in AsPC-1 cells. (C) Immunocytochemical detection of PEPT2 (red) in PEPT2-positive normal pancreas cell line (HPDE) and PDAC cell lines (AsPC-1, BxPC-3, Capan-1, and CFPAC-1). Nuclei stained with DAPI are blue. LAMP1 (green) was used as a lysosomal marker. Magnification, 60×. (D) Immunocytochemical detection of PEPT1 (green) in PEPT1-positive PDAC cell lines (AsPC-1, and SU.86.86). Nuclei stained with DAPI are blue. LAMP1 (red) was used as a lysosomal marker. Magnification, 60×. Data are given as mean ± SEM. * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001.