| 1 |
PI3K / Akt signaling |
↓ (context-dependent) |
↔ / physiological regulation |
Reduced proliferative and survival signaling |
One of the most reproducible proposed myo-inositol anticancer mechanisms. Reduced airway PI3K-activation signatures were observed particularly among clinical responders, but PI3K suppression is not universal across models. |
| 2 |
IL-6 / STAT3 inflammatory signaling |
↓ |
↓ pathological inflammatory signaling |
Reduced tumor-promoting inflammation |
Myo-inositol reduced IL-6-associated pathways and phospho-STAT3 in a KRAS-driven lung-cancer model. Human bronchial-dysplasia trial also demonstrated ↓ BAL IL-6. |
| 3 |
miR-125a-5p / IP6K1 axis |
miR-125a-5p ↑ IP6K1 ↓ |
Not established |
Reduced migration, EMT and metastasis |
Demonstrated in MDA-MB-231 triple-negative breast-cancer cells. Hormone-responsive MCF-7 cells were comparatively resistant, demonstrating substantial subtype dependence. |
| 4 |
EMT and metastatic phenotype |
↓ (model-dependent) |
↔ |
Reduced invasion and metastatic potential |
Closely linked to PI3K/Akt and miR-125a-5p/IP6K1 modulation rather than a completely independent mechanism. |
| 5 |
Cell proliferation |
↓ (dose-dependent) |
↔ / slight effect |
Growth inhibition |
Recent DU-145 experiments reported approximately 50% viability inhibition near 0.06 mg/mL after 72 hours while mouse L929 fibroblasts retained approximately 90% viability at the tested concentration. |
| 6 |
Apoptosis-associated signaling |
↑ (model-dependent) |
↔ |
Promotion of tumor-cell death |
Proteomic changes in DU-145 cells included ↑ APAF1 and alterations in other apoptosis/stress-associated proteins. Evidence for direct myo-inositol-induced apoptosis is substantially less extensive than for IP6. |
| 7 |
Macrophage and tumor microenvironment signaling |
Indirect suppression |
M1 antitumor phenotype ↑ |
Less tumor-supportive microenvironment |
KRAS-driven mouse lung lesions showed reduced macrophage recruitment and phenotype remodeling toward an antitumor M1 profile. |
| 8 |
ERK / MAPK signaling |
↓ (context-dependent) |
↔ / physiological regulation |
Reduced mitogenic signaling |
Supported mainly by broader inositol literature. Evidence specifically isolating unphosphorylated myo-inositol from IP6 and other inositol phosphates is less robust. |
| 9 |
Glucose metabolism / insulin signaling |
Modulated (context-dependent) |
Insulin sensitivity ↑ |
Metabolic normalization |
Myo-inositol has well-established metabolic signaling activity, but the consequences for cancer are complex and cannot be assumed to be uniformly antitumor. |
| 10 |
AMPK metabolic signaling |
↓ / mixed (context-dependent) |
Context-dependent |
Altered metabolic-state signaling |
A mechanistic caution: inositol can inhibit AMPK in some settings. Because AMPK can either suppress proliferation or promote survival under metabolic stress, this pathway may produce opposing effects depending on tumor state. |
| 11 |
SLC5A3-dependent inositol uptake |
Potentially ↑ growth |
Physiological uptake |
Context-dependent tumor nutrient support |
Important paradoxical mechanism. Some NSCLC cells overexpress SLC5A3 and depend on intracellular myo-inositol for Akt-mTOR activity and proliferation, indicating that greater inositol availability is not intrinsically anticancer in every tumor. |
| 12 |
Clinical Translation Constraint |
Context-dependent response |
Generally well tolerated |
Limits therapeutic interpretation |
Phase IIb bronchial-dysplasia RCT failed to demonstrate a significant overall primary-endpoint benefit. Tumor genotype, estrogen signaling, transporter expression and metabolic state appear capable of determining response. High oral doses can cause gastrointestinal adverse effects. |