ABCG2 and cancer: In terms of pathways (Figure 6), in the BxPC-3 groups, ABC-transporter, glycerophospholipid and purine metabolism were identified as discriminatory cancer-associated metabolic pathway between SX and OX models while more pathways, including central carbon metabolism in cancer, biosynthesis of aminoacyl-tRNA and amino acids, 2-oxocarboxylic acid metabolism and protein digestion and absorption, were identified in Panc-1 groups.