Description: <b>Lycopene</b> is a naturally occurring carotenoid found predominantly in tomatoes and other red fruits and vegetables. <br>
<p><b>Lycopene</b> — a highly lipophilic, acyclic C40 carotenoid (tetraterpene) responsible for the red coloration of tomatoes, watermelon, pink grapefruit, guava, and related foods. It is a non-provitamin-A carotenoid and dietary bioactive rather than an approved anticancer drug. Standard abbreviations include Lyc and LYCO. Tomatoes and processed tomato products are the dominant dietary sources in many populations. Lycopene isomers and oxidative metabolites may differ biologically; circulating and tissue lycopene contains a substantially larger cis-isomer fraction than typical raw tomato sources.</p>
<p><b>Primary mechanisms (ranked):</b></p>
<ol>
<li>Redox modulation: strong singlet-oxygen quenching and antioxidant activity predominate physiologically, while some cancer models show context-dependent mitochondrial ROS generation and pro-oxidant apoptosis.</li>
<li>IGF-1 / PI3K / AKT / mTOR growth signaling suppression, contributing to reduced proliferation and increased apoptosis in multiple experimental cancer models.</li>
<li>Mevalonate / HMG-CoA reductase / Ras signaling suppression, reducing cholesterol synthesis, protein prenylation, Ras membrane localization, and downstream proliferative signaling.</li>
<li>Cell-cycle inhibition through cyclin D1 and other cyclins/CDKs with increased p21/p27 and G0/G1 or other model-dependent arrest.</li>
<li>Intrinsic apoptosis modulation through increased Bax:Bcl-2 ratio, mitochondrial dysfunction, cytochrome-c release, and caspase activation in responsive cancer models.</li>
<li>Anti-inflammatory signaling through suppression of NF-κB, COX-2, IL-6, TNF-α and related inflammatory mediators.</li>
<li>Migration, invasion and EMT suppression involving FAK, MMP2/MMP9, β-catenin, Rho-family signaling and epithelial-mesenchymal transition pathways.</li>
<li>Anti-angiogenic signaling involving VEGF and HIF-1α suppression in selected experimental systems.</li>
<li>NRF2-dependent antioxidant defense is important primarily in normal-cell protection and chemoprevention models; its direction in established cancer is context-dependent rather than uniformly beneficial.</li>
</ol>
<p><b>Bioavailability / PK relevance:</b> Oral absorption is formulation- and food-matrix-dependent. Lycopene is lipophilic and incorporation into mixed micelles is improved by dietary fat, disruption of the tomato matrix by processing, and some cis-rich formulations. Human isotope studies indicate substantial interindividual variability and postabsorptive trans-to-cis isomerization. Plasma/tissue persistence is relatively long compared with many phytochemicals, but reported half-life depends strongly on the kinetic model and whether endogenous/background lycopene is being measured.<br>
- tangerine tomato juice has a marked 8.5-fold increase in lycopene bioavailability compared to red tomato juice<br>
- taking with olive oil improves bioavailability.
- Lycopene from fresh and unprocessed tomatoes is poorly absorbed by humans. Absorption of lycopene is higher from processed foods such as tomato paste and tomato juice heated in oil.<br>
- cis-isomers of lycopene are more bioavailable than trans-lycopene probably because cis-isomers are more soluble in bile acid micelles.(tomato-based foods contain mainly all-trans-lycopene) <br
- fibre decreases lycopene bioavailability. <br>
>
</p>
<p><b>In-vitro vs systemic exposure relevance:</b> Many anticancer experiments use approximately 1–20 µM lycopene, with several mechanistic studies clustering near 2.5–10 µM. Human circulating concentrations after dietary or supplemental intake are generally much lower than the upper concentrations used experimentally; therefore mechanisms demonstrated at high micromolar concentrations should not automatically be assumed achievable in tumors after ordinary oral supplementation. Formulation, food matrix, tissue accumulation and lycopene metabolites further complicate direct concentration comparisons.</p>
<p><b>Clinical evidence status:</b> RCT / small human / observational evidence, but not established anticancer treatment. Human studies are strongest for biomarker modulation and prostate-related research, while prospective epidemiology generally associates higher dietary or circulating lycopene with modestly lower cancer risk. Trials have not established lycopene as a replacement for standard cancer therapy. Lycopene is used as a food constituent and dietary supplement; FDA GRAS determinations for specified food uses are not anticancer drug approvals.</p>
<br>
Antioxidant Properties:<br>
-Lycopene is a powerful antioxidant. It helps neutralize free radicals, which can reduce oxidative stress—a factor implicated in cancer development. Possible
<a href="https://nestronics.ca/dbx/tbResEdit.php?rid=3273">concern</a>
about interfering with chemotherapy and radiation therapy.
However this
<a href="https://nestronics.ca/dbx/tbResEdit.php?rid=3281">review </a>disagrees.<br>
Inflammation Reduction:<br>
-Some studies suggest that lycopene may help lower levels of inflammation, another process linked to cancer progression<br>
<br>
At supraphysiological or extremely high concentrations, lycopene may have the potential to switch from an antioxidant to a prooxidant role<br>
-The prooxidant effect of lycopene has been observed under conditions of high oxygen tension. In vitro studies have suggested that in environments with elevated oxygen levels, lycopene might promote rather than neutralize the production of reactive oxygen species (ROS).<br>
-The presence of metal ions (such as iron or copper) in the environment can catalyze reactions where antioxidants, including lycopene, contribute to oxidative processes. These metals can interact with lycopene, potentially leading to the formation of radicals.<br>
<br>
The mevalonate pathway produces cholesterol and a variety of isoprenoids, which are important for maintaining cell membrane integrity, protein prenylation, and other essential cellular functions.<br>
-One of the primary enzymes in this pathway is HMG-CoA reductase (3-hydroxy-3-methylglutaryl-coenzyme A reductase), which is the target of statin drugs used for lowering cholesterol.
Some studies suggest that lycopene might downregulate the activity of HMG-CoA reductase or other enzymes in the mevalonate pathway. By doing so, lycopene could potentially reduce the synthesis of cholesterol and isoprenoids that are necessary for rapid cell proliferation—an especially relevant aspect in cancer cells.<br>
<br>
Lycopene typically used in a 100mg/day range for cancer (inhibition of the the Melavonate Pathway)<br>
-also has <a href="tbResList.php?qv=119&tsv=10&wNotes=on&exSp=open">antiplatelet </a>aggregation capability.<br>
<br>
-Note <a href="tbResList.php?qv=119&tsv=1109&wNotes=on&exSp=open">half-life</a> 16–20 days (other ref 5 days).<br>
<a href="tbResList.php?qv=119&tsv=792&wNotes=on&exSp=open">BioAv</a> Heat processing, especially when combined with a small amount of fat, significantly enhances lycopene’s bioaccessibility and absorption. (20% under optimal conditions)
<br>
Pathways:<br>
<!-- ROS : MMP↓, ER Stress↑, Ca+2↑, Cyt‑c↑, Casp3↑, Casp9↑, DNAdam↑, UPR↑, cl-PARP↑-->
- <a href="tbResList.php?qv=119&tsv=275&wNotes=on">ROS</a> usually goes down, but may go up or down depending on dose and environment. Lycopene may also be modified to be a "oxdiative product" which may change the behaviour.<br>
<!--
- ROS↑ related:
<a href="tbResList.php?qv=119&tsv=197&wNotes=on&word=MMP↓">MMP↓</a>(ΔΨm),
<a href="tbResList.php?qv=119&tsv=103&wNotes=on">ER Stress↑</a>,
<a href="tbResList.php?qv=119&tsv=459&wNotes=on">UPR↑</a>,
<a href="tbResList.php?qv=119&tsv=356&wNotes=on">GRP78↑</a>,
<a href="tbResList.php?qv=119&tsv=38&wNotes=on&word=Ca+2↑">Ca+2↑</a>,
<a href="tbResList.php?qv=119&tsv=77&wNotes=on">Cyt‑c↑</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=Casp">Caspases↑</a>,
<a href="tbResList.php?qv=119&tsv=82&wNotes=on&word=DNAdam↑">DNA damage↑</a>,
<a href="tbResList.php?qv=119&tsv=239&wNotes=on">cl-PARP↑</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=HSP">HSP↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=Prx">Prx</a>,
<br>
<!--
<!-- ANTIOXIDANT : NRF2, SOD, GSH, CAT, HO-1, GPx, GPX4, -->
<!--
- Lowers AntiOxidant defense in Cancer Cells:
<a href="tbResList.php?qv=119&tsv=226&wNotes=on&word=NRF2↓">NRF2↓</a>,
<a href="tbResList.php?qv=119&word=Trx&wNotes=on">TrxR↓**</a>,
<a href="tbResList.php?qv=119&tsv=298&wNotes=on&word=SOD↓">SOD↓</a>,
<a href="tbResList.php?qv=119&tsv=137&wNotes=on&word=GSH↓">GSH↓</a>
<a href="tbResList.php?qv=119&tsv=46&wNotes=on">Catalase↓</a>
<a href="tbResList.php?qv=119&tsv=597&wNotes=on">HO1↓</a>
<a href="tbResList.php?qv=119&wNotes=on&word=GPx">GPx↓</a>
<br>
-->
- Raises
<a href="tbResList.php?qv=119&tsv=1103&wNotes=on&word=antiOx↑">AntiOxidant</a>
defense in Normal Cells:
<a href="tbResList.php?qv=119&tsv=275&wNotes=on&word=ROS↓">ROS↓</a>,
<a href="tbResList.php?qv=119&tsv=226&wNotes=on&word=NRF2↑">NRF2↑</a>,
<a href="tbResList.php?qv=119&tsv=298&wNotes=on&word=SOD↑">SOD↑</a>,
<a href="tbResList.php?qv=119&tsv=137&wNotes=on&word=GSH↑">GSH↑</a>,
<a href="tbResList.php?qv=119&tsv=46&wNotes=on&word=Catalase↑">Catalase↑</a>,
<br>
<!-- INFLAMMATION : NF-kB↓, COX2↓, COX2↓ PRO-INFL CYTOKINES: IL-1β↓, TNF-α↓, IL-6↓, IL-8↓, -->
- lowers
<a href="tbResList.php?qv=119&tsv=953&wNotes=on&word=Inflam">Inflammation</a> :
<a href="tbResList.php?qv=119&tsv=214&wNotes=on&word=NF-kB↓">NF-kB↓</a>,
<a href="tbResList.php?qv=119&tsv=66&wNotes=on&word=COX2↓">COX2↓</a>,
<a href="tbResList.php?qv=119&tsv=235&wNotes=on&word=p38↓">p38↓</a>, Pro-Inflammatory Cytokines :
<a href="tbResList.php?qv=119&tsv=908&wNotes=on&word=NLRP3↓">NLRP3↓</a>,
<a href="tbResList.php?qv=119&tsv=978&wNotes=on&word=IL1β↓">IL-1β↓</a>,
<a href="tbResList.php?qv=119&tsv=309&wNotes=on&word=TNF-α↓">TNF-α↓</a>,
<a href="tbResList.php?qv=119&tsv=158&wNotes=on&word=IL6↓">IL-6↓</a>,
<a href="tbResList.php?qv=119&tsv=368&wNotes=on&word=IL8↓">IL-8↓</a>
<br>
<!-- GROWTH/METASTASES : EMT↓, MMPs↓, MMP2↓, MMP9↓, IGF-1, uPA↓, VEGF↓, ERK↓
inhibiting metastasis-associated proteins such as ROCK1, FAK, (RhoA), NF-κB and u-PA, MMP-1 and MMP-13.-->
- inhibit Growth/Metastases :
<!-- <a href="tbResList.php?qv=119&tsv=604&wNotes=on">TumMeta↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=323&wNotes=on">TumCG↓</a>, -->
<a href="tbResList.php?qv=119&tsv=96&wNotes=on">EMT↓</a>,
<a href="tbResList.php?qv=119&tsv=204&wNotes=on">MMPs↓</a>,
<!-- <a href="tbResList.php?qv=119&tsv=201&wNotes=on">MMP2↓</a>, -->
<a href="tbResList.php?qv=119&tsv=203&wNotes=on">MMP9↓</a>,
<!-- <a href="tbResList.php?qv=119&tsv=308&wNotes=on">TIMP2</a>, -->
<a href="tbResList.php?qv=119&tsv=415&wNotes=on">IGF-1↓</a>,
<a href="tbResList.php?qv=119&tsv=428&wNotes=on">uPA↓</a>,
<a href="tbResList.php?qv=119&tsv=334&wNotes=on">VEGF↓</a>,
<a href="tbResList.php?qv=119&tsv=1284&wNotes=on">ROCK1↓</a>,
<a href="tbResList.php?qv=119&tsv=110&wNotes=on">FAK↓</a>,
<a href="tbResList.php?qv=119&tsv=273&wNotes=on">RhoA↓</a>,
<a href="tbResList.php?qv=119&tsv=214&wNotes=on">NF-κB↓</a>,
<!-- <a href="tbResList.php?qv=119&tsv=79&wNotes=on">CXCR4↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=1247&wNotes=on">SDF1↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=304&wNotes=on">TGF-β↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=719&wNotes=on">α-SMA↓</a>, -->
<a href="tbResList.php?qv=119&tsv=105&wNotes=on">ERK↓</a>
<!-- <a href="tbResList.php?qv=119&tsv=1178&wNotes=on">MARK4↓</a> --> <!-- contributing to tumor growth, invasion, and metastasis-->
<br>
<!-- REACTIVATE GENES : HDAC↓, DNMT1↓, DNMT3A↓, EZH2↓, P53↑, -->
- reactivate genes thereby inhibiting cancer cell growth :
<!-- <a href="tbResList.php?qv=119&tsv=140&wNotes=on">HDAC↓</a>, -->
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=DNMT">DNMTs↓</a>, -->
<a href="tbResList.php?qv=119&tsv=108&wNotes=on">EZH2↓</a>,
<a href="tbResList.php?qv=119&tsv=236&wNotes=on">P53↑</a>,
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=HSP">HSP↓</a>, -->
<a href="tbResList.php?qv=119&tsv=506&wNotes=on">Sp proteins↓</a>,
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=TET">TET↑</a> -->
<br>
<!-- CELL CYCLE ARREST : TumCCA↑, cyclin D1↓, cyclin E↓, CDK2↓, CDK4↓, CDK6↓ -->
- cause Cell cycle arrest :
<a href="tbResList.php?qv=119&tsv=322&wNotes=on">TumCCA↑</a>,
<a href="tbResList.php?qv=119&tsv=73&wNotes=on">cyclin D1↓</a>,
<a href="tbResList.php?qv=119&tsv=378&wNotes=on">cyclin E↓</a>,
<a href="tbResList.php?qv=119&tsv=467&wNotes=on">CDK2↓</a>,
<a href="tbResList.php?qv=119&tsv=894&wNotes=on">CDK4↓</a>,
<!-- <a href="tbResList.php?qv=119&tsv=895&wNotes=on">CDK6↓</a>, -->
<br>
<!-- MIGRATION/INVASION : TumCMig↓, TumCI↓, FAK↓, ERK↓, -->
- inhibits Migration/Invasion :
<a href="tbResList.php?qv=119&tsv=326&wNotes=on">TumCMig↓</a>,
<a href="tbResList.php?qv=119&tsv=324&wNotes=on">TumCI↓</a>,
<a href="tbResList.php?qv=119&tsv=309&wNotes=on&word=TNF-α↓">TNF-α↓</a>, <!-- encourages invasion, proliferation, EMT, and angiogenesis -->
<a href="tbResList.php?qv=119&tsv=110&wNotes=on">FAK↓</a>,
<a href="tbResList.php?qv=119&tsv=105&wNotes=on">ERK↓</a>,
<a href="tbResList.php?qv=119&tsv=96&wNotes=on">EMT↓</a>,
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=TOP">TOP1↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=657&wNotes=on">TET1</a>, -->
<br>
<!-- GLYCOLYSIS : ATP↓, HIF-1α↓, PKM2↓, cMyc↓, PDK1↓, GLUT1↓, LDHA↓, HK2↓, Glucose↓, GlucoseCon↓, lactateProd, OXPHOS -->
<!--
- inhibits
<a href="tbResList.php?qv=119&tsv=129&wNotes=on">glycolysis</a>
/<a href="tbResList.php?qv=119&tsv=947&wNotes=on">Warburg Effect</a> and
<a href="tbResList.php?qv=119&tsv=21&wNotes=on&word=ATP↓">ATP depletion</a> :
<a href="tbResList.php?qv=119&tsv=143&wNotes=on">HIF-1α↓</a>,
<a href="tbResList.php?qv=119&tsv=772&wNotes=on">PKM2↓</a>,
<a href="tbResList.php?qv=119&tsv=35&wNotes=on">cMyc↓</a>,
<a href="tbResList.php?qv=119&tsv=566&wNotes=on&word=GLUT">GLUT1↓</a>,
<a href="tbResList.php?qv=119&tsv=906&wNotes=on">LDH↓</a>,
<a href="tbResList.php?qv=119&tsv=175&wNotes=on&word=LDH">LDHA↓</a>,
<a href="tbResList.php?qv=119&tsv=773&wNotes=on">HK2↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=PFK">PFKs↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=PDK">PDKs↓</a>,
<a href="tbResList.php?qv=119&tsv=847&wNotes=on">ECAR↓</a>,
<a href="tbResList.php?qv=119&tsv=230&wNotes=on">OXPHOS↓</a>,
<a href="tbResList.php?qv=119&tsv=356&wNotes=on">GRP78↑</a>,
<a href="tbResList.php?qv=119&tsv=1278&wNotes=on">Glucose↓</a>,
<a href="tbResList.php?qv=119&tsv=623&wNotes=on">GlucoseCon↓</a>
<br>
-->
<!-- ANGIOGENESIS : VEGF↓, VEGFR2↓, HIF-1α↓, NOTCH↓, FGF↓, PDGF↓, EGFR↓ ITG(Integrins↓)-->
- inhibits
<a href="tbResList.php?qv=119&tsv=447&wNotes=on">angiogenesis↓</a> :
<a href="tbResList.php?qv=119&tsv=334&wNotes=on">VEGF↓</a>,
<a href="tbResList.php?qv=119&tsv=143&wNotes=on">HIF-1α↓</a>,
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=NOTCH">Notch↓</a>, -->
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=FGF">FGF↓</a>, -->
<!-- <a href="tbResList.php?qv=119&wNotes=on&word=PDGF">PDGF↓</a>, -->
<!-- <a href="tbResList.php?qv=119&tsv=94&wNotes=on&word=EGFR↓">EGFR↓</a>, -->
<a href="tbResList.php?qv=119&&wNotes=on&word=ITG">Integrins↓</a>,
<br>
<!-- CSCs : CSC↓, CK2↓, Hh↓, GLi↓, GLi1↓, -->
<!--
- inhibits Cancer Stem Cells :
<a href="tbResList.php?qv=119&tsv=795&wNotes=on">CSC↓</a>,
<a href="tbResList.php?qv=119&tsv=524&wNotes=on">CK2↓</a>,
<a href="tbResList.php?qv=119&tsv=141&wNotes=on">Hh↓</a>,
<a href="tbResList.php?qv=119&tsv=434&wNotes=on">GLi↓</a>,
<a href="tbResList.php?qv=119&tsv=124&wNotes=on">GLi1↓</a>,
<a href="tbResList.php?qv=119&tsv=677&wNotes=on">CD133↓</a>,
<a href="tbResList.php?qv=119&tsv=655&wNotes=on">CD24↓</a>,
<a href="tbResList.php?qv=119&tsv=342&wNotes=on">β-catenin↓</a>,
<a href="tbResList.php?qv=119&tsv=357&wNotes=on">n-myc↓</a>,
<a href="tbResList.php?qv=119&tsv=656&wNotes=on">sox2↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=NOTCH">Notch2↓</a>,
<a href="tbResList.php?qv=119&tsv=1024&wNotes=on">nestin↓</a>,
<a href="tbResList.php?qv=119&tsv=508&wNotes=on">OCT4↓</a>,
<br>
-->
<!-- OTHERS : -->
- Others: <a href="tbResList.php?qv=119&tsv=252&wNotes=on">PI3K↓</a>,
<a href="tbResList.php?qv=119&tsv=4&wNotes=on">AKT↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=JAK">JAK↓</a>,
<a href="tbResList.php?qv=119&wNotes=on&word=STAT">STAT↓</a>,
<a href="tbResList.php?qv=119&tsv=377&wNotes=on">Wnt↓</a>,
<a href="tbResList.php?qv=119&tsv=342&wNotes=on">β-catenin↓</a>,
<a href="tbResList.php?qv=119&tsv=9&wNotes=on">AMPK</a>,
<!-- <a href="tbResList.php?qv=119&tsv=475&wNotes=on">α↓</a>, -->
<a href="tbResList.php?qv=119&tsv=105&wNotes=on">ERK↓</a>,
<!-- <a href="tbResList.php?qv=119&tsv=1014&wNotes=on">5↓</a>, -->
<a href="tbResList.php?qv=119&tsv=168&wNotes=on">JNK</a>,
- <a href="tbResList.php?qv=119&wNotes=on&word=SREBP">SREBP</a> (related to cholesterol).<br>
<!-- SYNERGIES : -->
- Synergies:
<a href="tbResList.php?qv=119&tsv=1106&wNotes=on">chemo-sensitization</a>,
<a href="tbResList.php?qv=119&tsv=1171&wNotes=on">chemoProtective</a>,
<a href="tbResList.php?qv=119&tsv=1107&wNotes=on">RadioSensitizer</a>,
<a href="tbResList.php?qv=119&tsv=1185&wNotes=on">RadioProtective</a>,
<a href="tbResList.php?qv=119&tsv=961&esv=2&wNotes=on&exSp=open">Others(review target notes)</a>,
<a href="tbResList.php?qv=119&tsv=1105&wNotes=on">Neuroprotective</a>,
<a href="tbResList.php?qv=119&tsv=557&wNotes=on">Cognitive</a>,
<a href="tbResList.php?qv=119&tsv=1175&wNotes=on">Renoprotection</a>,
<a href="tbResList.php?qv=119&tsv=1179&wNotes=on">Hepatoprotective</a>,
<a href="tbResList.php?&qv=119&tsv=1188&wNotes=on">CardioProtective</a>,
<br>
<br>
<!-- SELECTIVE: -->
- Selectivity:
<a href="tbResList.php?qv=119&tsv=1110&wNotes=on">Cancer Cells vs Normal Cells</a><br>
<br>
<h3>Lycopene Mechanistic Ranking</h3>
<table border="1" cellspacing="0" cellpadding="4">
<thead>
<tr>
<th>Rank</th>
<th>Pathway / Axis</th>
<th>Cancer Cells</th>
<th>Normal Cells</th>
<th>TSF</th>
<th>Primary Effect</th>
<th>Notes / Interpretation</th>
</tr>
</thead>
<tbody>
<tr>
<td>1</td>
<td>Redox and reactive oxygen species</td>
<td>ROS ↓ or ↑ (context-dependent); mt-ROS ↑ in selected models</td>
<td>ROS ↓; lipid peroxidation ↓</td>
<td>R–G</td>
<td>Redox modulation</td>
<td>Antioxidant behavior predominates physiologically, but pro-oxidant mitochondrial ROS-mediated apoptosis occurs in some cancer models. Direction depends on cell type, oxygen tension, dose and lycopene oxidation state.</td>
</tr>
<tr>
<td>2</td>
<td>IGF-1 / PI3K / AKT / mTOR</td>
<td>IGF-1 signaling ↓; PI3K ↓; AKT ↓; mTOR ↓</td>
<td>↔ or protective modulation (context-dependent)</td>
<td>R–G</td>
<td>Growth and survival signaling ↓</td>
<td>One of the most recurrent cancer-relevant signaling clusters; effects vary by tumor model.</td>
</tr>
<tr>
<td>3</td>
<td>Mevalonate / HMG-CoA reductase / Ras</td>
<td>HMG-CoA reductase ↓; cholesterol synthesis ↓; membrane Ras ↓</td>
<td>LDL/cholesterol regulation ↓ (context-dependent)</td>
<td>G</td>
<td>Growth signaling and prenylation ↓</td>
<td>Mechanistically important but demonstrated mainly preclinically. Mevalonate can reverse lycopene-induced growth inhibition in experimental cancer cells.</td>
</tr>
<tr>
<td>4</td>
<td>Cell-cycle machinery</td>
<td>Cyclin D1 ↓; cyclin E ↓; CDK2 ↓; CDK4 ↓; p21 ↑; p27 ↑; arrest ↑</td>
<td>↔ (generally spared)</td>
<td>G</td>
<td>Proliferation ↓</td>
<td>Frequently reported downstream consequence of growth-factor, Ras and AKT pathway suppression.</td>
</tr>
<tr>
<td>5</td>
<td>Mitochondrial apoptosis</td>
<td>Bax:Bcl-2 ↑; MMP ↓; Cyt-c ↑; caspase-9 ↑; caspase-3 ↑; apoptosis ↑</td>
<td>Mitochondrial damage ↓; apoptosis ↓ under oxidative injury</td>
<td>R–G</td>
<td>Selective death signaling</td>
<td>Direction differs markedly by malignant versus stressed normal-cell context.</td>
</tr>
<tr>
<td>6</td>
<td>NF-κB inflammatory signaling</td>
<td>NF-κB ↓; COX-2 ↓; IL-6 ↓; TNF-α ↓</td>
<td>NF-κB ↓; inflammatory cytokines ↓</td>
<td>R–G</td>
<td>Inflammation ↓</td>
<td>Supported across cancer and non-cancer inflammatory models; likely partly secondary to redox and kinase modulation.</td>
</tr>
<tr>
<td>7</td>
<td>EMT / FAK / MMP invasion axis</td>
<td>EMT ↓; FAK ↓; MMP2 ↓; MMP9 ↓; migration ↓; invasion ↓</td>
<td>↔ (context-dependent)</td>
<td>G</td>
<td>Migration and invasion ↓</td>
<td>Relevant mainly to preclinical metastatic phenotypes rather than demonstrated clinical antimetastatic efficacy.</td>
</tr>
<tr>
<td>8</td>
<td>Wnt / β-catenin / STAT3</td>
<td>Wnt ↓; β-catenin ↓; JAK1 ↓; STAT3 ↓</td>
<td>↔ (context-dependent)</td>
<td>G</td>
<td>Proliferative transcription ↓</td>
<td>Observed in several epithelial cancer models but not established as a universal primary target.</td>
</tr>
<tr>
<td>9</td>
<td>VEGF / HIF-1α angiogenesis</td>
<td>VEGF ↓; HIF-1α ↓; angiogenesis ↓</td>
<td>↔ or angiogenic signaling ↓ (context-dependent)</td>
<td>G</td>
<td>Angiogenesis ↓</td>
<td>Predominantly preclinical evidence.</td>
</tr>
<tr>
<td>10</td>
<td>NRF2 / antioxidant response</td>
<td>NRF2 ↑ or ↓ (context-dependent)</td>
<td>NRF2 ↑; HO-1 ↑; NQO1 ↑; SOD ↑; GSH defense ↑</td>
<td>R–G</td>
<td>Stress defense ↑</td>
<td>NRF2 activation is well supported in protective normal-tissue models. In established cancer, NRF2 biology is dual-sided and should not be represented as uniformly anticancer.</td>
</tr>
<tr>
<td>11</td>
<td>DNA damage and genomic protection</td>
<td>DNA damage ↑ or ↓ (model-dependent); p53 ↑</td>
<td>Oxidative DNA damage ↓</td>
<td>G</td>
<td>Context-dependent genomic modulation</td>
<td>Normal-cell chemoprevention and cancer-cell killing can produce opposite apparent directions.</td>
</tr>
<tr>
<td>12</td>
<td>Glycolysis and metabolic signaling</td>
<td>Glycolysis ↓ (limited evidence); c-Myc ↓; G6PD ↓</td>
<td>↔</td>
<td>G</td>
<td>Metabolic growth support ↓</td>
<td>Evidence is substantially less developed than for AKT, cell cycle or redox pathways; should remain secondary.</td>
</tr>
<tr>
<td>13</td>
<td>Chemosensitization</td>
<td>Sensitivity ↑ (drug- and model-dependent)</td>
<td>Chemotoxicity may ↓ in protective models</td>
<td>G</td>
<td>Adjunct response modulation</td>
<td>Preclinical sensitization has been reported, including androgen-axis therapies; simultaneous cytoprotection is also reported with some cytotoxic agents, so interaction cannot be generalized.</td>
</tr>
<tr>
<td>14</td>
<td>Radiosensitivity and radioprotection</td>
<td>↔ or sensitivity ↑ (model-dependent)</td>
<td>Radioprotection ↑ in some models</td>
<td>G</td>
<td>Context-dependent radiation interaction</td>
<td>Evidence supports both antioxidant radioprotection and experimental radiosensitization depending on system; clinical significance remains uncertain.</td>
</tr>
<tr>
<td>15</td>
<td>Clinical Translation Constraint</td>
<td>Oral tumor exposure uncertain</td>
<td>Generally well tolerated at nutritional and commonly studied supplemental exposure</td>
<td>G</td>
<td>Translation limited</td>
<td>Low and variable oral bioavailability, food-matrix effects, nonlinear dose-exposure relationships, uncertain tumor concentrations, and limited adequately powered cancer RCTs constrain translation of high-concentration in-vitro mechanisms.</td>
</tr>
</tbody>
</table>
<p><b>TSF:</b> P: 0–30 min R: 30 min–3 hr G: >3 hr</p>
<br>
<hr>
<br>
<p><b>Alzheimer’s disease relevance:</b> Lycopene has meaningful preclinical AD relevance but no established clinical efficacy. Cell and animal models report reduced oxidative stress and neuroinflammation, improved mitochondrial function, suppression of BACE1 and amyloidogenic signaling, reduced Aβ burden, attenuation of tau hyperphosphorylation, and preservation of BDNF/synaptic signaling. Human evidence remains insufficient to classify lycopene as an AD treatment.</p>
<p><b>Translation status:</b> Preclinical only for disease-modifying AD mechanisms. Computational, cellular, rodent and formulation studies support biological plausibility, but clinical supplementation studies have not demonstrated prevention or treatment of Alzheimer’s disease.</p>
<h3>Lycopene in Alzheimer’s Disease Models</h3>
<table border="1" cellspacing="0" cellpadding="4">
<thead>
<tr>
<th>Rank</th>
<th>Pathway / Axis</th>
<th>Modulation</th>
<th>Primary Effect</th>
<th>Notes / Interpretation</th>
</tr>
</thead>
<tbody>
<tr>
<td>1</td>
<td>Oxidative stress / NRF2</td>
<td>ROS ↓; NRF2 ↑; antioxidant defense ↑</td>
<td>Oxidative neuronal injury ↓</td>
<td>One of the most consistent effects in cellular and animal neurotoxicity models.</td>
</tr>
<tr>
<td>2</td>
<td>Amyloid / BACE1</td>
<td>BACE1 ↓; Aβ ↓</td>
<td>Amyloidogenic processing ↓</td>
<td>Supported experimentally; no demonstrated disease-modifying effect in humans.</td>
</tr>
<tr>
<td>3</td>
<td>Neuroinflammation / NF-κB</td>
<td>NF-κB ↓; TNF-α ↓; IL-1β ↓; IL-6 ↓</td>
<td>Neuroinflammation ↓</td>
<td>Reported in several Aβ and inflammatory animal models.</td>
</tr>
<tr>
<td>4</td>
<td>Mitochondrial function</td>
<td>mt-ROS ↓; MMP preserved; mitochondrial damage ↓</td>
<td>Bioenergetic integrity ↑</td>
<td>Consistent with antioxidant and anti-apoptotic neuronal effects.</td>
</tr>
<tr>
<td>5</td>
<td>Tau phosphorylation</td>
<td>Hyperphosphorylated tau ↓</td>
<td>Tau pathology ↓</td>
<td>Demonstrated in transgenic mouse models; human relevance remains unproven.</td>
</tr>
<tr>
<td>6</td>
<td>BDNF / synaptic plasticity</td>
<td>BDNF ↑; TrkB signaling ↑</td>
<td>Synaptic resilience ↑</td>
<td>Preclinical evidence suggests preservation of learning/memory pathways.</td>
</tr>
<tr>
<td>7</td>
<td>Neuronal apoptosis</td>
<td>Bax:Bcl-2 ↓; Cyt-c ↓; caspase-3 ↓</td>
<td>Neuronal survival ↑</td>
<td>Predominantly secondary to redox, mitochondrial and inflammatory modulation.</td>
</tr>
</tbody>
</table>