Fig. 2. CD133+ cells accumulate metabolites in biosynthetic pathway: ¹³C₆ glucose labeling of CD133+ cells isolated from KPC tumors showed the glucose was being routed via the pentose phosphate pathway to make lactate instead of following canonical glycolysis.

a Relative abundance of the metabolites (M1-M7) in pentose phosphate pathway in CD133+ and CD133− cells after labeling with ¹³C₆ glucose for 15 min. Increased accumulation of M+ 6 isotopologue (6-PG, M+ 5 isotopologue in R5P/X5P, and M+ 5, M+ 6 and M+ 7 isotopologue can be observed in CD133+ cells (b). CD133+ cells had increased G6PD activity compared to CD133− cells in cells isolated from KPC tumors (c) as well as when CD133 was overexpressed in MIA-PACA2 cell line (d). Similarly, enzymes in the pentose phosphate pathway were overexpressed in CD133+ cells isolated from the KPC tumors (e). Further, CD133+ cells did not incorporate BrDU indicating that they were not synthesizing nucleic acids actively (f).