Materials and Reagents

1. 0.5 ml K₂-EDTA collection tubes (BD, catalog number: 363706 )
   
2. Sterile syringes and gauge 30 needles (Thermo Fisher Scientific, catalog number: 10142534 )
   
3. 5-inch squares Al foil
   
4. Indelible marker pens (black)-Sharpie fine tip
   
5. Pasteur pipet
   
6. Lancets (MEDIpoint, Inc., model: Goldenrod 5 mm )
   
7. Mice bearing tumor xenograft
   Note: The strain of immunocompromised recipient mouse depends on type of implant. Young NOD/SCID Gamma (NSG) mice are especially favorable for the patient derived xenograft (PDX) model.
   
8. Ketamine for anesthesia if needed, Schedule III controlled substance (Sigma-Aldrich, catalog number: K2753 )
   
9. Tracer [e.g., ¹³C₆-glucose, ¹³C₂-1, 2-glucose (60 mg/mouse), or ¹³C₅, ¹⁵N₂-glutamine (22 mg/mouse)]
   
10. Sources
    
    1. D-Glucose-¹³C₆ (Cambridge Isotope Laboratories, Inc., catalog number: CLM-1396-CTM )
       
    2. D-Glucose-1, 2-¹³C₂ (Cambridge Isotope Laboratories, Inc., catalog number: CLM-504 )
       
    3. L-Glutamine-¹³C₅, ¹⁵N₂ (Cambridge Isotope Laboratories, Inc., catalog number: CNLM-1275 )
       
    Or
    
    4. D-Glucose-¹³C₆ (Sigma-Aldrich, catalog number: 660663 )
       
    5. D-Glucose-1, 2-¹³C₂ (Sigma-Aldrich, catalog number: 661422 )
       
    6. L-Glutamine-¹³C₅, ¹⁵N₂ (Sigma-Aldrich, catalog number: 607983 )
11. Liquid nitrogen
    
12. 70% ethanol
    
13. 10% Neutral buffered formalin (Thermo Fisher Scientific, Protocol^TM, catalog number: 032-059 )
    
14. 25% w/v sterile filtered (0.2 µm) ¹³C glucose in PBS
    Note: Stock solution can be frozen and stored at -25 °C.
    
15. Sterile wipes (Uline, catalog number: S-16183 )
    
16. Sodium Chloride (NaCl) (Thermo Fisher Scientific, catalog number: S271-1 )
    
17. Potassium chloride (KCl) (Sigma-Aldrich, catalog number: P9541 )
    
18. Sodium phosphate dibasic (Na₂HPO₄) anhydrous (Sigma-Aldrich, catalog number: S-0876 )
    
19. Potassium phosphate monobasic (KH₂PO₄) anhydrous (Sigma-Aldrich, catalog number: P9791 )
    
20. 10x Phosphate Buffered Saline (PBS) (see Recipes)
    
21. Stock solution for 0.2% ¹³C₆-glucose (see Recipes)
    
22. Stock solution for ¹³C₅, ¹⁵N₂-Gln (10 ml) (see Recipes)
    

Equipment

1. Mouse restraining system (Plas-Labs, Inc., model: 541-RR )
   
2. FirstHand Surgical Instrument Kits for Mice and Rats (Kent Scientific Corporation, model: INSMOUSEKIT )
   
3. Blue wax dissection tray (VWR International, catalog number: 10060-188 )
   
4. Warming blanket (Kent Scientific Corporation, model: DCT-15 )
   
5. Water bottle with DI water (Thermo Fisher Scientific, catalog number: 02-897-11 )
   
6. Polystyrene Weigh boats (USA Scientific Inc., catalog number: 2347-1427 )
   
7. Calipers for measuring tumor size (Thermo Fisher Scientific, catalog number: 15-077-957 )
   
8. 2-place Balance for weighing tissues (VWR International, Adventurer Ohaus^®, catalog number: 10153-744 )
   
9. Refrigerated Microfuge (Eppendorf, model: 5417R with rotor)
   
10. Dewar/bucket (Nalgene plastic dewar) for lN₂ (Thermo Fisher Scientific, catalog number: S34074C )
    
11. Large Styrofoam box
    

Procedure