Fig. 7.

6PGD inhibitor Physcion inhibits cancer cell metabolism and proliferation. (a-d) H1299 cells were assayed for intracellular concentration of 6-PG (a) and Ru-5-P (b), NADPH/NADP⁺ ratio (c), as well as oxidative PPP flux and biosynthesis of RNA and lipids (d) in the presence and absence of Physcion. (e) H1299 cells were treated with increasing concentrations of Physcion, followed by Western blot to detect phosphorylation levels of ACC1 (pS79; upper) and AMPK (pT172; lower). 6PGD KD cells were included as a control. (f) Cell lysates of S3-treated H1299 cells were used for immunoprecipitation of MO25 and Western blot to detect co-immunoprecipiated LKB1 and STRAD. (g-h) H1299 cells treated with or without Physcion were assayed for general ROS levels (g) and cell proliferation rates by cell counting (h) in the presence and absence of NAC. (i) H1299 cells treated with or without Physcion were assayed for cell proliferation rates by cell counting in the presence and absence of Compound C (left) or lentivirus harboring AMPK shRNA (right). (j-o) Effects of treatment with Physcion on LKB1-deficient A549 cells were assayed for 6PGD activity (j), intracellular Ru-5-P levels (k), phosphorylation levels of AMPK (l) and lipid biosynthesis (m), as well as general ROS levels (n) and cell proliferation rates by cell counting (o) in the presence and absence of NAC. (p-s) Effects of Physcion treatment on normal proliferating HaCaT cells were assayed for 6PGD activity (p), intracellular Ru-5-P levels (q), phosphorylation levels of AMPK and lipid biosynthesis (r), as well as cell proliferation rates by cell counting (s). (a-s) Data are from a single experiment that is representative of 3 independent experiments for (b-c, e) and 2 independent experiments for (a, d, f-s). Source data for independent replications and experiments with sample size<5 are available in Supplementary Table 1. Uncropped Western blots are provided in Supplementary Figure 9.