| Rank |
Pathway / Axis |
Cancer / Tumor Context |
Normal Tissue Context |
TSF |
Primary Effect |
Notes / Interpretation |
| 1 |
Redox cycling (quinone-mediated ROS generation) |
ROS ↑; oxidative stress ↑; apoptosis ↑ (dose-dependent) |
Oxidative injury risk ↑ (hemolysis, hepatotoxicity) |
P, R |
Primary cytotoxic mechanism |
Menadione undergoes one-electron redox cycling, generating superoxide and hydrogen peroxide; not selective for tumor cells. |
| 2 |
Glutathione (GSH) depletion |
GSH ↓; redox buffering capacity ↓ |
Red cell vulnerability ↑ |
P, R |
Redox destabilization |
Conjugation and oxidative cycling consume GSH, amplifying oxidative stress. |
| 3 |
Mitochondrial dysfunction |
ΔΨm ↓; ATP ↓; apoptosis signaling ↑ |
Energy stress in normal cells possible |
R, G |
Mitochondria-mediated apoptosis |
ROS and redox imbalance disrupt mitochondrial membrane potential. |
| 4 |
DNA damage (oxidative) |
DNA strand breaks ↑ (reported) |
Genotoxic risk ↑ |
R, G |
Genome instability |
Often secondary to ROS accumulation rather than direct DNA intercalation. |
| 5 |
Synergy with ascorbate (Vitamin C) |
Redox cycling ↑; cytotoxicity ↑ (reported in vitro) |
Systemic oxidative injury risk ↑ |
P, R |
Redox amplification |
Menadione can undergo redox cycling with ascorbate, increasing ROS production; largely preclinical data. |
| 6 |
Topoisomerase interference (reported) |
Topo inhibition (context-dependent) |
↔ |
R |
Secondary mechanism |
Some studies report interference with topoisomerase activity, but this is not the dominant mechanism. |
| 7 |
Hemolysis risk (G6PD vulnerability) |
— |
Red blood cell destruction risk ↑ |
R |
Major toxicity constraint |
Menadione can cause hemolytic anemia, especially in G6PD deficiency. |
| 8 |
Hepatotoxicity |
— |
Liver injury risk ↑ |
G |
Clinical toxicity constraint |
Historical reason for discontinuation as a human supplement. |
| 9 |
Vitamin K–dependent clotting pathway |
Minimal physiologic role in humans |
Not equivalent to K1/K2 |
— |
Classification clarification |
Menadione is a synthetic precursor; does not function identically to phylloquinone (K1) or menaquinones (K2). |