Melatonin / PKM2 Cancer Research Results

MEL, Melatonin: Click to Expand ⟱
Features:
Hormone in the body made by pineal gland.
• Melatonin is a potent antioxidant. It neutralizes reactive oxygen species (ROS) and reactive nitrogen species (RNS), which are involved in DNA damage and cancer progression.
• Melatonin has been shown to modulate apoptotic pathways by influencing mitochondrial permeability, cytochrome c release, and caspase activation.
• In several cancer cell models, melatonin appears to promote apoptosis in malignant cells while sparing normal cells.

The most well-known indolamines are serotonin and melatonin, both of which play significant roles in regulating mood, sleep, and overall mental well-being.

Melatonin doses (20 mg to even 40 mg per day), often given as an adjuvant treatment for cancer.
-The plasma half-life of melatonin is generally in the range of approximately 20 to 60 minutes
-It has been suggested that administering melatonin at the appropriate phase of the circadian cycle may enhance its anti-tumor activity and reduce the side effects of chemotherapy and radiation therapy.

Bio-availability: Oral melatonin has a low and variable bio-availability (often estimated between 3% and 33%), which means that only a fraction of the ingested dose reaches the bloodstream unchanged.

For proOxidant effect might need >10uM, which might be 100mg dose (assuming 10% bio-availability) Might also be required X10 levels?
-It remains unknown whether the pro-oxidant action exists in vivo. the vast majority of evidence indicates that melatonin is a potent antioxidant in vivo even at pharmacological concentrations.

Interactions:
-Melatonin could potentially add to the blood pressure–lowering properties of antihypertensive drugs.
-Patients using insulin should be monitored for changes in blood glucose levels.
-Melatonin might interact with drugs like warfarin, aspirin, or clopidogrel.(antiplatelet)


Melatonin Cancer Relevant Pathways
Rank Pathway / Axis Cancer Cells Normal Cells Label Primary Interpretation Notes
1 Circadian signaling (MT1 / MT2 receptors) ↓ proliferative circadian disruption ↑ circadian synchronization Driver Chronobiology normalization Melatonin restores circadian control; cancer cells lose growth advantages from circadian dysregulation
2 Reactive oxygen species (ROS) ↓ ROS (baseline); context-dependent ↑ stress signaling ↓ ROS (strong buffering) Driver Antioxidant dominance with signaling effects Melatonin is a potent direct and indirect antioxidant; cancer cells may still undergo stress-mediated growth inhibition
3 Mitochondrial function ↓ metabolic flexibility; ↑ apoptosis sensitivity ↑ mitochondrial efficiency Secondary Mitochondrial stabilization vs vulnerability Melatonin improves mitochondrial function in normal cells while limiting metabolic plasticity in cancer cells
4 Estrogen signaling (ERα modulation) ↓ estrogen-driven proliferation ↔ minimal Secondary Hormone-dependent growth suppression Particularly relevant in breast and hormone-responsive cancers
5 NF-κB signaling ↓ inflammatory / survival signaling ↓ inflammatory tone Secondary Anti-inflammatory modulation NF-κB suppression contributes to reduced tumor-promoting inflammation
6 Cell cycle regulation ↓ proliferation / ↑ arrest ↔ spared Phenotypic Cytostatic growth control Growth inhibition reflects upstream circadian and hormonal effects
7 Apoptosis sensitivity ↑ sensitivity to apoptosis (chemo/RT) ↓ apoptosis Phenotypic Therapy sensitization Melatonin enhances response to chemo- and radiotherapy while protecting normal tissue


PKM2, Pyruvate Kinase, Muscle 2: Click to Expand ⟱
Source:
Type: enzyme
PKM2 (Pyruvate Kinase, Muscle 2) is an enzyme that plays a crucial role in glycolysis, the process by which cells convert glucose into energy. PKM2 is a key regulatory enzyme in the glycolytic pathway, and it is primarily expressed in various tissues, including muscle, brain, and cancer cells.
-C-myc is a common oncogene that enhances aerobic glycolysis in the cancer cells by transcriptionally activating GLUT1, HK2, PKM2 and LDH-A
-PKM2 has been shown to be overexpressed in many types of tumors, including breast, lung, and colon cancer. This overexpression may contribute to the development and progression of cancer by promoting glycolysis and energy production in cancer cells.
-inhibition of PKM2 may cause ATP depletion and inhibiting glycolysis.
-PK exists in four isoforms: PKM1, PKM2, PKR, and PKL
-PKM2 plays a role in the regulation of glucose metabolism in diabetes.
-PKM2 is involved in the regulation of cell proliferation, apoptosis, and autophagy.
– Pyruvate kinase catalyzes the final, rate-limiting step of glycolysis, converting phosphoenolpyruvate (PEP) to pyruvate with the production of ATP.
– The PKM2 isoform is uniquely regulated and can exist in both highly active tetrameric and less active dimeric forms.
– Cancer cells often favor the dimeric form of PKM2 to slow pyruvate production, thereby accumulating upstream glycolytic intermediates that can be diverted into anabolic pathways to support cell growth and proliferation.
– Under low oxygen conditions, cancer cells rely on altered metabolic pathways in which PKM2 is a key player. – The shift to aerobic glycolysis (Warburg effect) orchestrated in part by PKM2 helps tumor cells survive and grow in hypoxic conditions.

– Elevated expression of PKM2 is frequently observed in many cancer types, including lung, breast, colorectal, and pancreatic cancers.
– High levels of PKM2 are often correlated with enhanced tumor aggressiveness, poor differentiation, and advanced clinical stage.

PKM2 in carcinogenesis and oncotherapy

Inhibitors of PKM2:
-Shikonin, Resveratrol, Baicalein, EGCG, Apigenin, Curcumin, Ursolic Acid, Citrate (best known as an allosteric inhibitor of phosphofructokinase-1 (PFK-1), a key rate-limiting enzyme in glycolysis) potential to directly inhibit or modulate PKM2 is less well established

Full List of PKM2 inhibitors from Database
-key connected observations: Glycolysis↓, lactateProd↓, ROS↑ in cancer cell, while some result for opposite effect on normal cells.
Tumor pyruvate kinase M2 modulators

Flavonoids effect on PKM2
Compounds name IC50/AC50uM Effect
Flavonols
1. Fisetin 0.90uM Inhibition
2. Rutin 7.80uM Inhibition
3. Galangin 8.27uM Inhibition
4. Quercetin 9.24uM Inhibition
5. Kaempferol 9.88uM Inhibition
6. Morin hydrate 37.20uM Inhibition
7. Myricetin 0.51uM Activation
8. Quercetin 3-b- D-glucoside 1.34uM Activation
9. Quercetin 3-D -galactoside 27-107uM Ineffective
Flavanons
10. Neoeriocitrin 0.65uM Inhibition
11. Neohesperidin 14.20uM Inhibition
12. Naringin 16.60uM Inhibition
13. Hesperidin 17.30uM Inhibition
14. Hesperitin 29.10uM Inhibition
15. Naringenin 70.80uM Activation
Flavanonols
16. (-)-Catechin gallateuM 0.85 Inhibition
17. (±)-Taxifolin 1.16uM Inhibition
18. (-)-Epicatechin 1.33uM Inhibition
19. (+)-Gallocatechin 4-16uM Ineffective
Phenolic acids
20. Ferulic 11.4uM Inhibition
21. Syringic and 13.8uM Inhibition
22. Caffeic acid 36.3uM Inhibition
23. 3,4-Dihydroxybenzoic acid 78.7uM Inhibition
24. Gallic acid 332.6uM Inhibition
25. Shikimic acid 990uM Inhibition
26. p-Coumaric acid 22.2uM Activation
27. Sinapinic acids 26.2uM Activation
28. Vanillic 607.9uM Activation


Scientific Papers found: Click to Expand⟱
6419- MEL,    The potential influence of melatonin on mitochondrial quality control: a review
- Review, Nor, NA
*mt-ACC⇅, *PKM1↑, *PKM2↑, *Glycolysis↝, *PDKs↑, *FAO↑, *ETC↑, *OXPHOS↑, *ATP↑, Glycolysis↓, OXPHOS↑, *Ca+2↓, *ROS↓, *antiOx↑, *SOD2↑, *GPx↑, *Catalase↑, *MFN1↑, *MFN2↑, *OPA1↑, *YAP/TEAD↑, *Hippo↑, *SIRT1↑, *PGC-1α↑, *DRP1/DNM1L↓,

Showing Research Papers: 1 to 1 of 1

* indicates research on normal cells as opposed to diseased cells
Total Research Paper Matches: 1

Pathway results for Effect on Cancer / Diseased Cells:


Redox & Oxidative Stress

OXPHOS↑, 1,  

Core Metabolism/Glycolysis

Glycolysis↓, 1,  
Total Targets: 2

Pathway results for Effect on Normal Cells:


NA, unassigned

DRP1/DNM1L↓, 1,   MFN1↑, 1,   MFN2↑, 1,   OPA1↑, 1,  

Redox & Oxidative Stress

antiOx↑, 1,   Catalase↑, 1,   GPx↑, 1,   OXPHOS↑, 1,   ROS↓, 1,   SOD2↑, 1,  

Mitochondria & Bioenergetics

ATP↑, 1,   ETC↑, 1,   PGC-1α↑, 1,  

Core Metabolism/Glycolysis

mt-ACC⇅, 1,   FAO↑, 1,   Glycolysis↝, 1,   PDKs↑, 1,   PKM1↑, 1,   PKM2↑, 1,   SIRT1↑, 1,  

Cell Death

Hippo↑, 1,   YAP/TEAD↑, 1,  

Migration

Ca+2↓, 1,  
Total Targets: 23

Scientific Paper Hit Count for: PKM2, Pyruvate Kinase, Muscle 2
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#:122  Target#:772  State#:%  Dir#:%
wNotes=0 sortOrder:rid,rpid

 

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