Metformin / mTOR Cancer Research Results

MET, Metformin: Click to Expand ⟱
Features: oral antidiabetic agent,
Metformin is a pleiotropic drug: attributed to its action on AMPK
Metformin is a biguanide drug used primarily for type 2 diabetes. Mechanistically, it is best described as a bioenergetic modulator: partial inhibition of mitochondrial respiration can raise AMP/ADP, engage AMPK, and suppress mTORC1 signaling; systemically it reduces hepatic gluconeogenesis and can lower insulin/IGF-1 growth signaling. In oncology, observational studies suggested improved outcomes in some settings, but randomized trial data are mixed (e.g., large adjuvant breast cancer data did not show broad benefit overall). Long-term use can be associated with vitamin B12 deficiency, and prescribing requires attention to renal function due to rare lactic acidosis risk in predisposed states.
Metformin directly(partially) inhibits Complex I of the electron transport chain (ETC) in mitochondria. This inhibition decreases mitochondrial ATP production and forces cells to rely more on glycolysis for energy.
Cancer cells, especially those with high energy demands, may be particularly sensitive to a drop in ATP levels. The inhibition of Complex I also increases the AMP/ATP ratio, setting the stage for the activation of downstream energy stress pathways.
AMPK activation results in the inhibition of the mammalian target of rapamycin (mTOR) pathway, a central regulator of protein synthesis and cellular growth. mTOR inhibition reduces cell proliferation and limits tissue growth, which can slow tumor progression.

Metformin reduces circulating insulin levels, which in turn can decrease the activation of the insulin and insulin-like growth factor-1 (IGF-1) receptor pathways.

ETC Inhibitors: Drugs that directly inhibit specific ETC complexes (e.g., Complex I inhibitors like metformin or phenformin) can increase electron leakage and ROS production.(dose- and context-dependent, and not consistent)

-known as mild OXPHOS inhibitor(Complex I modulator)

Rank Pathway / Axis Cancer / Tumor Context Normal Tissue Context TSF Primary Effect Notes / Interpretation
1 Mitochondrial Complex I (OXPHOS) inhibition Energetic stress ↑; proliferation pressure ↓ (context) Hepatic energy shift; gluconeogenesis ↓ P, R Bioenergetic modulation Metformin partially inhibits mitochondrial Complex I (OXPHOS), increasing AMP/ADP ratio and triggering downstream AMPK activation. ROS changes are dose- and context-dependent.
2 AMPK activation (LKB1/AMPK axis) Growth programs ↓ (context-dependent) Metabolic homeostasis ↑ R Energy-sensor activation AMPK activation is frequently invoked downstream of respiratory inhibition, though some hepatic effects can be AMPK-independent.
3 mTORC1 inhibition (via AMPK→TSC2/Raptor; also AMPK-independent routes reported) Protein synthesis / growth signaling ↓ (reported) Reduced anabolic signaling in liver (context) R, G Anti-anabolic signaling Mechanistically supported: AMPK regulation of TSC2 and Raptor contributes to metformin-mediated mTORC1 inhibition; AMPK-independent mTORC1 inhibition has also been described.
4 Hepatic gluconeogenesis suppression Indirect tumor support via insulin/IGF-1 lowering (systemic) Liver glucose production ↓ (core clinical effect) R, G Systemic metabolic effect Metformin reduces hepatic glucose output through multiple mechanisms (energy state shifts, cAMP pathways, and other proposed nodes).
5 Insulin / IGF-1 axis (systemic growth signaling) Mitogenic tone ↓ (context; strongest in hyperinsulinemic settings) Insulin sensitivity ↑; insulin levels ↓ (context) G Systemic growth-factor modulation Many “anti-cancer” hypotheses depend on lowering insulin/IGF-1 signaling rather than direct tumor cytotoxicity.
6 Cell-cycle & apoptosis (secondary, model-dependent) Proliferation ↓; apoptosis ↑ (reported in some models) ↔ G Conditional cytostasis Often downstream of mTORC1 suppression/energy stress; not a universal direct cytotoxin signature.
7 Inflammation signaling (NF-κB and related programs) Inflammatory pro-survival transcription ↓ (reported) Anti-inflammatory trends in metabolic disease contexts R, G Inflammation modulation Frequently reported as downstream of improved metabolic/oxidative stress tone; avoid presenting as a primary direct target.
8 Autophagy / stress adaptation Autophagy ↑ or ↓ depending on context; can affect therapy response ↔ G Adaptive stress response Autophagy findings are heterogeneous across tumor models and combinations.
9 Clinical oncology evidence (adjunct use) Observational signals exist; randomized data are mixed — — Translation constraint Epidemiology/meta-analyses suggested potential benefit in some cancers, but large randomized trials (e.g., adjuvant breast cancer MA.32) did not show broad benefit across the overall population.
10 Safety / monitoring constraints (B12, lactic acidosis risk in predisposed states) — Vitamin B12 deficiency risk with long-term use; rare lactic acidosis risk increases with renal impairment and other conditions — Clinical risk management Long-term B12 monitoring is commonly advised; prescribing requires renal function assessment due to lactic acidosis risk in predisposed settings.

Time-Scale Flag (TSF): P / R / G

  • P: 0–30 min (rapid bioenergetic effects)
  • R: 30 min–3 hr (acute signaling shifts: AMPK/mTOR)
  • G: >3 hr (gene-regulatory adaptation and phenotype outcomes)
mTOR, mammalian target of rapamycin: Click to Expand ⟱
Source: HalifaxProj (inhibit)
Type:
mTOR (mechanistic target of rapamycin) is a central regulator of cell growth, proliferation, metabolism, and survival. It is a serine/threonine kinase that integrates signals from nutrients, growth factors, and cellular energy status.
mTOR promotes protein synthesis and cell growth by activating downstream targets such as S6 kinase and 4E-BP1. In cancer, this pathway can become hyperactivated, leading to uncontrolled cell proliferation.

mTor Inhibitors:
-rapamycin (Sirolimus): classic natural product mTOR inhibitor
-Curcumin
-Resveratrol
-Epigallocatechin Gallate (EGCG)
-Honokiol
Scientific Papers found: Click to Expand⟱
2386- MET,    Mechanisms of metformin inhibiting cancer invasion and migration
- Review, Var, NA
OS↑, Also, in Canada, a large retrospective study was conducted, and the results indicated a 20% reduction of cancer-specific mortality among metformin users compared to its non-users
AMPK↑, Metformin inhibits invasion and migration through the AMPK signaling pathway
EMT↓, Metformin inhibits invasion and migration through EMT signaling pathways
TGF-β↓, The invasive ability of pancreatic cancer cells is suppressed by metformin by blocking signaling in the autocrine TGF-β1 pathway
mTOR↓, Furthermore, TGF-β1-induced EMT in cervical carcinoma cells is abolished by metformin through inhibiting the mTOR/p70s6k signaling pathway to down-regulate PKM2 expression
P70S6K↓,
PKM2↓,
Hif1a↓, Subsequently, it was discovered that gastric cancer was inhibited by metformin via the inhibition of HIF1α/PKM2 signaling
ChemoSen↑, it increased the sensitivity of chemotherapy drugs to different types of cancer

5795- MET,    Metformin: A Review of Potential Mechanism and Therapeutic Utility Beyond Diabetes
- Review, AD, NA - Review, Park, NA - Review, Diabetic, NA
*AntiDiabetic↑, Metformin has been designated as one of the most crucial first-line therapeutic agents in the management of type 2 diabetes mellitus.
*AMPK↑, acts majorly by activating AMPK (Adenosine Monophosphate-Activated Protein Kinase) in the cells and reducing glucose output from the liver.
*glyC↓, It also decreases advanced glycation end products and reactive oxygen species production in the endothelium apart from regulating the glucose and lipid metabolism
*ROS↓,
*cardioP↑, hence minimizing the cardiovascular risks.
*neuroP↑, Preclinical studies have also shown some evidence of metformin’s neuroprotective role in Parkinson’s disease, Alzheimer’s disease, multiple sclerosis and Huntington’s disease.
*Half-Life↝, The plasma half-life of metformin is 2–3 hours, and the active duration is about 6–10hrs.
*toxicity↝, Metformin use for an extended period is linked to a deficiency of vitamin B12.
*BioAv↑, Absolute bioavailability 50–60% in healthy individuals
*glucose↓, Conventionally, it is quite established that metformin lowers blood glucose primarily by its action on the liver
*AGEs↓, Metformin decreases the synthesis of AGE (“Advanced Glycation End”) product formation and hyperglycaemic-induced ROS (“Reactive Oxygen Species”) production
AntiCan↑, There is growing evidence that metformin has anti-cancer effects based on clinical and preclinical studies.
Risk↓, reported that metformin use might decrease the risk of lung cancer within T2D patients as compared to other conventional agents.
TumCP↓, Several studies on cancer cell lines have observed that metformin treatment leads to inhibition of development and proliferation and induces apoptosis of the cancer cells
Apoptosis↑,
TumCCA↑, Metformin was found to block the cell cycle in the “G(0)/G(1)” phase
cycD1/CCND1↓, and this was observed with a sharp drop in the cyclin D1 levels, pRb phosphorylation, and elevated p27(kip) expression.
pRB↓,
p27/CDKN1B↓,
mTOR↓, as well as inhibits the mTOR pathway that is activated by insulin.
Casp↑, Metformin is also responsible for inducing caspase-dependent apoptosis along with c- JNK (“Jun N-Terminal Kinase”) activation, oxidative stress and mitochondrial depolarization.
ROS↑,
MMP↓,
ChemoSen↑, patients who received metformin along with the chemotherapy had better pathologic responses as compared to the group without metformin
*hepatoP↑, effects including cardioprotective, hepatoprotective, anti-malignant, and geroprotective effects
*CRM↑, mechanism behind the process of calorie restriction is a reduction in insulin
*Insulin↓,

2374- MET,    Metformin Induces Apoptosis and Downregulates Pyruvate Kinase M2 in Breast Cancer Cells Only When Grown in Nutrient-Poor Conditions
- in-vitro, BC, MCF7 - in-vitro, BC, SkBr3 - in-vitro, BC, MDA-MB-231
eff↑, reduction of nutrient supply in tumors can increase metformin efficacy and that modulation of PKM2 expression/activity could be a promising strategy to boost metformin anti-cancer effect.
Apoptosis↑,
Glycolysis↓, Finally, we showed that, in nutrient-poor conditions, metformin was able to modulate the intracellular glycolytic equilibrium by downregulating PKM2 expression
PKM2↓,
mTOR↓, Glucose availability influences metformin effect on apoptosis without affecting its ability to downregulate the mTOR pathway
PARP↓, metformin ability to induce PARP inactivation

2377- MET,    Metformin Inhibits TGF-β1-Induced Epithelial-to-Mesenchymal Transition via PKM2 Relative-mTOR/p70s6k Signaling Pathway in Cervical Carcinoma Cells
- in-vitro, Cerv, HeLa - in-vitro, Cerv, SiHa
EMT↓, metformin partially abolished TGF-β1-induced EMT cell proliferation
P70S6K↓, Metformin decreased the p-p70s6k expression and the blockade of mTOR/p70s6k signaling decreased PKM2 expression.
mTOR↓,
PKM2↓,
Warburg↓, PKM2 regulates in the cancer-specific Warburg effect, which is responsible for the final rate-limiting step of glycolysis.
AMPK↑, direct mechanisms involving activating AMP-activated protein kinase (AMPK), followed by inhibition of the mammalian target of the rapamycin (mTOR) pathway

2378- MET,    Metformin inhibits epithelial-mesenchymal transition of oral squamous cell carcinoma via the mTOR/HIF-1α/PKM2/STAT3 pathway
- in-vitro, SCC, CAL27 - in-vivo, NA, NA
TumCP↓, metformin abolished CoCl2-induced cell proliferation, migration, invasion and EMT.
TumCMig↓,
TumCI↓,
EMT↓,
mTOR↓, Moreover, metformin reversed EMT in OSCC by inhibiting the mTOR-associated HIF-1α/PKM2/STAT3 signaling pathway.
Hif1a↓,
PKM2↓,
STAT3↓,
E-cadherin↑, In the CoCl2 group, E-cadherin expression was decreased, while vimentin and Snial1 expression was increased, which all could be reversed by metformin
Vim↓,
Snail↓,
STAT3↓, STAT3 expression was significantly increased in the CoCl2 group, but was significantly decreased by the addition of metformin


Showing Research Papers: 1 to 5 of 5

* indicates research on normal cells as opposed to diseased cells
Total Research Paper Matches: 5

Pathway results for Effect on Cancer / Diseased Cells:


Redox & Oxidative Stress(tgid=1) ⓘ

ROS↑, 1,  

Core Metabolism/Glycolysis(tgid=4) ⓘ

AMPK↑, 2,   Glycolysis↓, 1,   PKM2↓, 4,   Warburg↓, 1,  

Cell Death(tgid=5) ⓘ

Apoptosis↑, 2,   Casp↑, 1,  

Kinase & Signal Transduction(tgid=6) ⓘ

mTOR↓, 5,   P70S6K↓, 2,   STAT3↓, 2,  

DNA Damage & Repair(tgid=10) ⓘ

PARP↓, 1,  

Cell Cycle & Senescence(tgid=11) ⓘ

cycD1/CCND1↓, 1,   p27/CDKN1B↓, 1,   pRB↓, 1,   TumCCA↑, 1,  

Proliferation, Differentiation & Cell State(tgid=12) ⓘ

TumCP↓, 2,  

Migration(tgid=13) ⓘ

E-cadherin↑, 1,   EMT↓, 3,   Snail↓, 1,   TGF-β↓, 1,   TumCI↓, 1,   TumCMig↓, 1,   Vim↓, 1,  

Angiogenesis & Vasculature(tgid=14) ⓘ

Hif1a↓, 2,  

Barriers & Transport(tgid=15) ⓘ

MMP↓, 1,  

Drug Metabolism & Resistance(tgid=21) ⓘ

ChemoSen↑, 2,   eff↑, 1,  

Functional Outcomes(tgid=23) ⓘ

AntiCan↑, 1,   OS↑, 1,   Risk↓, 1,  
Total Targets: 30

Pathway results for Effect on Normal Cells:


Redox & Oxidative Stress(tgid=1) ⓘ

ROS↓, 1,  

Mitochondria & Bioenergetics(tgid=3) ⓘ

Insulin↓, 1,  

Core Metabolism/Glycolysis(tgid=4) ⓘ

AMPK↑, 1,   CRM↑, 1,   glucose↓, 1,   glyC↓, 1,  

Protein Aggregation(tgid=19) ⓘ

AGEs↓, 1,  

Drug Metabolism & Resistance(tgid=21) ⓘ

BioAv↑, 1,   Half-Life↝, 1,  

Functional Outcomes(tgid=23) ⓘ

AntiDiabetic↑, 1,   cardioP↑, 1,   hepatoP↑, 1,   neuroP↑, 1,   toxicity↝, 1,  
Total Targets: 14

Scientific Paper Hit Count for: mTOR, mammalian target of rapamycin
5 Metformin
Query results interpretion may depend on "conditions" listed in the research papers.
Such Conditions may include : 
  -low or high Dose
  -format for product, such as nano of lipid formations
  -different cell line effects
  -synergies with other products 
  -if effect was for normal or cancerous cells

Filter Conditions: Pro/AntiFlg:%  IllCat:%  CanType:%  Cells:%  prod#:11  Target#:209  State#:%  Dir#:1
  wNotes=on  sortOrder:rid,rpid

 

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