Figure 3.

Lung SCC increase glutaminolysis in vivo following treatment with MLN128.

(A) Changes in relative uptake of glucose and glutamine by RH2 cells in response to treatment with 50 nM MLN128 for 72 hr; n = 6 for Vehicle and MLN128. (B) RH2 tumor xenografts stained for GLUT1 and SLC1A5. Scale bar = 50 μm. (C) Dosing and PET imaging regimen for RH2 xenografts treated with Vehicle or MLN128 (D) ¹⁸F-FDG uptake measured by % ID/g in RH2 xenografts following treatment as described in (C); n = 7 (Vehicle), n= 17 (MLN128). (E) Representative images from RH2 tumors stained for Ki67 or p4EBP1 from mice treated daily with Vehicle or MLN128 as described in (C). Scale bar = 100 μm. (F) Quantification of Ki67 (left) and p4EBP1 (right) from Vehicle (n = 7) and MLN128 (n = 18) treatment groups. (G) Tumor volumes of RH2 xenografts following treatment with Vehicle (n = 7) or MLN128 (n = 17). (H) Overview of dosing and ¹³C₆-Glucose infusion of RH2 xenografts. (I) Schematic of isotopomer conversion from fully labeled glucose. (J, K, and L) Graphs representing percent M3 labeled lactate (J), M2 labeled citrate (K) and M3 labeled aspartate (L) in RH2 tumors from mice treated with Vehicle (n = 4) or MLN128 (n = 6) and infused with ¹³C₆-Glucose. (M) Overview of dosing and ¹³C₅-Glutamine infusion of RH2 xenografts. (N). Schematic of isotopomer conversion from fully labeled glutamine. (O, P, and Q) Graphs representing percent M5 labeled glutamine (O), M5 labeled glutamate (P) and M4 labeled aspartate (Q) in RH2 tumors from mice treated with Vehicle (n = 5) or MLN128 (n = 6) and infused with ¹³C₅-Glutamine. The data are represented as the mean ± SEM. Statistical significance (*p<0.05; **p<0.01; ***<0.001; ****p<0.0001; ns, not significant) was calculated using two-tailed t test. See also Figure S3.