Hypoxia-inducible factor 1 alpha (HIF-1α) is one important driver in hypoxic tumor regions. HIF-1α upregulates glycolytic genes (e.g., GLUT1, HK2, LDHA) and promotes reduced mitochondrial pyruvate oxidation in part through induction of PDK (which inhibits PDH), shifting carbon toward lactate.
| Node |
What It Does (Warburg role) |
Representative Inhibitors / Modulators |
Mechanism Snapshot |
Typical Tumor Effects |
Best-Fit Tumor Context |
Common Constraints / Gotchas |
TSF |
Combination Logic |
GLUT (glucose uptake) GLUT1 (SLC2A1) focus |
Controls glucose entry; sets the upper bound on glycolytic flux. |
Research/repurposing: WZB117 (GLUT1), BAY-876 (GLUT1), STF-31 (GLUT1 tool), Fasentin (GLUT), Phloretin (broad, weak)
Dietary/indirect: some polyphenols reported to lower GLUT1 expression (context)
|
Blocks glucose transport or reduces GLUT1 expression → less substrate for glycolysis & PPP. |
ATP stress (in highly glycolytic tumors), lactate ↓, growth slowdown; can sensitize to stressors. |
High-GLUT1 tumors; hypoxic / glycolysis-addicted phenotypes. |
Systemic glucose handling and glucose-dependent tissues; tumor compensation via alternate fuels. |
P, R |
Pairs with ROS/ETC stressors or LDH/MCT blockade; beware compensatory glutaminolysis/fatty acid oxidation. |
Hexokinase (HK2) first committed glycolysis step |
Traps glucose as G-6-P; HK2 often upregulated and mitochondria-associated in tumors. |
Clinical/adjunct interest: 2-Deoxyglucose (2-DG; glycolysis + glycosylation stress)
Research: Lonidamine-class glycolysis axis drugs (not “pure HK2”), 3-bromopyruvate (hazardous research agent; not for casual use)
|
Competitive substrate mimic (2-DG) → 2-DG-6P accumulation; HK flux ↓; ER glycosylation stress ↑. |
ATP ↓, AMPK ↑, ER stress/UPR ↑, autophagy ↑, apoptosis (context); radiosensitization reported. |
Highly glycolytic tumors; tumors with strong HK2 dependence; hypoxic cores. |
Normal glucose-dependent tissues; ER-stress toxicities; dosing/tolerability limits in practice. |
P, R, G |
Pairs with radiation, pro-oxidant stress, or MCT/LDH blockade; watch systemic glucose effects. |
LDH (LDHA/LDHB) pyruvate ⇄ lactate |
Regenerates NAD+ to sustain glycolysis; LDHA supports lactate production and acidification. |
Tier A direct inhibitors: FX11, (R)-GNE-140, NCI-006, Oxamate, Galloflavin, Gossypol
Tier B indirect: polyphenols (often lactate/LDH expression ↓ rather than catalytic inhibition)
|
Blocks LDH catalysis → NAD+ recycling ↓ → glycolysis throttles; pyruvate handling shifts; redox pressure ↑. |
Lactate ↓, glycolytic flux ↓, oxidative stress ↑ (often secondary), growth inhibition; immune microenvironment may improve if lactate decreases. |
LDHA-high tumors; lactate-driven immunosuppression; glycolysis-addicted phenotypes. |
Metabolic plasticity: tumors switch fuels; some LDH inhibitors have PK liabilities; “LDH release” ≠ LDH inhibition. |
R, G |
Pairs with MCT inhibition (trap lactate), NAD+ axis inhibitors, immune therapy (lactate suppression logic), and OXPHOS stressors (context). |
MCT (lactate transport) MCT1 (SLC16A1), MCT4 (SLC16A3) |
Exports lactate + H+ (acidifies TME); enables lactate shuttling between tumor subclones. |
Clinical-stage: AZD3965 (MCT1 inhibitor; clinical trials)
Research: AR-C155858 (MCT1/2), Syrosingopine (MCT1/4; repurposed), Lonidamine (MCT + MPC axis)
|
Blocks lactate export/import → intracellular acid stress ↑ (in glycolytic cells) and lactate shuttling ↓. |
Acid stress, growth inhibition; may improve immune function by reducing lactate/acidic suppression (context). |
MCT1-high tumors; oxidative “lactate-using” tumor fractions; tumors with lactate shuttling. |
MCT4-driven export can bypass MCT1-only inhibitors; hypoxia upregulates MCT4; need target matching. |
P, R |
Pairs strongly with LDH inhibitors (cut production + block export), and with immune therapy rationale (lactate/acid microenvironment). |
PDK (PDK1-4) PDH gatekeeper |
PDK inhibits PDH → keeps pyruvate out of mitochondria; supports Warburg by favoring lactate. |
Prototype: Dichloroacetate (DCA; pan-PDK inhibitor “classic”)
Research: AZD7545 (PDK2 inhibitor; tool), newer PDK inhibitor series (research)
|
Inhibits PDK → PDH active ↑ → pyruvate into TCA/OXPHOS ↑; lactate pressure ↓. |
Warburg reversal pressure (context), lactate ↓, mitochondrial flux ↑; can increase ROS in some settings (secondary). |
PDK-high tumors; tumors with suppressed PDH flux; “glycolysis locked” metabolic phenotype. |
Requires functional mitochondrial capacity; hypoxia can limit OXPHOS shift; effect is often modulatory rather than directly cytotoxic. |
R, G |
Pairs with therapies that exploit mitochondrial dependence or redox stress; can complement LDH/MCT strategies by reducing lactate drive. |