High expression of G6PD is associated with poor prognosis in colorectal cancer. (a) Expression profiling of PPP pathway related enzymes, including G6PD, H6PD, PGD, RPIA, RPE and TKT, in 483 primary CRC tissues and 41 adjacent normal tissues (TCGA). (b) G6PD is overexpressed in CRC tissues from our hospital (SYSUCC) analyzed by qPCR assay, and other microarray data sets available from Oncomine (https://www.oncomine.com//). (c) Immunoblotting analysis of G6PD expression in eight matched CRC tissues (T) and adjacent noncancerous tissues (N). (d) Immunoblotting and qPCR analysis of G6PD expression in two colorectal epithelial cells and six colorectal cancer cell lines. Data are presented as the mean±s.d. (n=3) **P<0.01 for indicated comparison (Student unpaired t-test). (e) Two representative cases show high expression of G6PD in human CRC tumor tissues (T) compared with adjacent normal tissues (ANT) tissues analyzed by IHC staining. (g) Two representative cases are shown (left) and percentage of specimens with low or high G6PD expression, relative to the response to FOLFOX or XELOX chemotherapy analyzed again by Pearson Chi square test (right). (f, h) The overall survival and progression-free survival curves of patients with low and high G6PD expression are generated using the Kaplan–Meier method and the log-rank test. PD, progressive disease; CR, complete response; PR, partial response; and SD, stable disease. Scale bar: 100 μm. β-Actin was used as a loading control.