Article Figures & Data
Figures
- FIGURE 1.
Simplified schematic of central cellular metabolic pathways (A) emphasizing key branch points and imaging targets (B). glucosee = extracellular glucose; glucosei = intracellular glucose; G-6-P = glucose-6-phosphate; 6-P-G = 6-phosphogluconate; Ru-5-P = ribulose-5-phosphate; Ri-5-P = ribose-5-phosphate; X-5-P = xylulose 5-phosphate; S-7-P = sedoheptulose 7-phosphate; GA-3-P = glyceraldehyde 3-phosphate; F-6-P = fructose 6-phosphate; E-4-P = erythrose 4-phosphate; PPP = pentose phosphate pathway; F-1,6-BP = fructose 1,6-bisphosphate; DHAP = dihydroxyacetone phosphate; PEP = phosphoenolpyruvate; lactatei = intracellular lactate; lactatee = extracellular lactate; CO2 = carbon dioxide; α-KG = α-ketoglutarate; OAA = oxaloacetate; O2 = oxygen; ADP = adenosine diphosphate; Pi = inorganic phosphate; glutaminee = extracellular glutamine; glutaminei = intracellular glutamine. (Adapted and reprinted with permission of (4).)
- FIGURE 2.
(A, top) Chemical diagram showing metabolism of [1-13C]pyruvate to [1-13C]lactate catalyzed by lactate dehydrogenase. (A, bottom) Representative 13C spectra obtained after injection of hyperpolarized [1-13C]pyruvate show increased [1-13C]lactate relative to [1-13C]pyruvate in prostate cancer compared with normal prostate. (B) T2-weighted MR image from different patient shows findings of prostate cancer (yellow square) and adjacent normal contralateral prostate (turquoise square), as well as a vessel outside prostate (green square). (C–E) Curves fit from 2-dimensional 13C dynamic MRSI acquisitions in this patient demonstrate increased flux of [1-13C]pyruvate to [1-13C]lactate in corresponding regions of prostate cancer (D) compared with normal prostate (C) and vasculature outside prostate (E). (Adapted and reprinted with permission of (75).)
- FIGURE 3.
(A) T1-weighted MRI with contrast shows minimal enhancement (arrowheads) along surgical cavity (dotted line) in glioma patient. Corresponding 18F-FDG PET image shows uptake in tumor posteriorly but not anteriorly (arrowheads). Corresponding 18F-glutamine (Gln) PET image shows tumor uptake both posteriorly and anteriorly. This patient had clinically progressive disease. (Adapted and reprinted with permission of (79).) (B) Schematic of glutamine metabolism and effect of glutaminase inhibitors. With glutaminase inhibition, cellular glutamine increases whereas cellular glutamate decreases. (C, top) 18F-glutamine PET images of triple-negative breast cancer xenograft show increased 18F-glutamine uptake after glutaminase inhibition reflecting increased glutamine pool size. (C, bottom) In contrast, receptor-positive breast cancer xenograft shows high uptake of 18F-glutamine at baseline without increase after glutaminase inhibition reflecting inherently low glutaminase activity. (Adapted and reprinted with permission of (81).)
- FIGURE 4.
Comparison of bone scan, 18F-FDG PET, and 11C-acetate PET before (A) and after (B) androgen deprivation therapy in patient with osseous metastases from prostate cancer. 11C-acetate demonstrates response to treatment. Bone scan does not demonstrate significant change, and 18F-FDG PET fails to detect osseous metastases at either time point. PSA = prostate-specific antigen level. (Reprinted with permission of (100).)
