Ivermectin and Cancer

Induces apoptosis

1. Ivermectin can cause programmed cancer cell death, also known as apoptosis. In various cancer cells, ivermectin can trigger the intrinsic mitochondrial pathway of apoptosis by:

How ivermectin causes cancer cell apoptosis

• Scientific reviews and studies have outlined several potential mechanisms by which ivermectin appears to induce cancer cell death in the laboratory:

Mitochondrial dysfunction:

• Cancer cells have high metabolic demands. Ivermectin can inhibit mitochondrial complex I, a key enzyme in the electron transport chain, which disrupts the cell’s energy (ATP) production. This metabolic collapse can trigger apoptosis.

Production of reactive oxygen species (ROS):

• The disruption of mitochondrial function caused by ivermectin leads to the overproduction of ROS, also known as oxidative stress. Excessive ROS damages the cancer cell’s DNA and other components, which activates the cell’s programmed cell death pathway.

Modulation of apoptosis-related proteins:

• Ivermectin has been shown to alter the balance of pro-apoptotic and anti-apoptotic proteins. By upregulating proteins like Bax and downregulating proteins like Bcl-2, it shifts the cellular environment to favor apoptosis.

Activation of caspase cascades:

• The mitochondrial pathway activated by ivermectin leads to the release of cytochrome c into the cytoplasm, which triggers a cascade of enzymes called caspases, specifically caspase-9 and caspase-3. These caspases carry out the final stages of the cell death program.

Inhibition of cell signaling pathways:

• Ivermectin can interfere with specific pathways that are critical for cancer cell survival and proliferation, such as the Akt/mTOR and Wnt/β-catenin pathways. Blocking these pathways indirectly promotes apoptosis.

Inhibits cancer cell proliferation:

Ivermectin can inhibit cancer cell proliferation through multiple molecular mechanisms, including disrupting mitochondrial function, inducing programmed cell death (apoptosis and autophagy), and modulating key signaling pathways involved in cell growth.

1. A key mechanism by which ivermectin inhibits cancer cells is by attacking their mitochondria, the primary energy producers for a cell.

   • Impairs energy production: Ivermectin inhibits mitochondrial complex I, a critical component of the electron transport chain. This disrupts the cancer cell’s ability to produce ATP, leading to an energy crisis that halts rapid cell growth.

   • Generates oxidative stress: The disruption of the electron transport chain leads to an overproduction of reactive oxygen species (ROS). This oxidative stress damages DNA and other cellular components, triggering cell death.

   • Causes mitochondrial dysfunction: The effects of ivermectin lead to a decrease in mitochondrial membrane potential and overall mitochondrial dysfunction, which can trigger the intrinsic pathway of apoptosis.

   Ivermectin induces several forms of programmed cell death in cancer cells while sparing normal cells.

   • Apoptosis: Ivermectin induces apoptosis, or programmed cell death, in cancer cells through the activation of both intrinsic and extrinsic caspase-dependent pathways. This mechanism involves mitochondrial dysfunction, a decrease in mitochondrial membrane potential, and the generation of reactive oxygen species (ROS), ultimately leading to DNA fragmentation and chromatin condensation, hallmarks of apoptosis. Ivermectin’s apoptotic effect is observed across various cancer types, including urothelial carcinoma, colorectal cancer, and esophageal squamous cell carcinoma.

   • Caspase Activation: Ivermectin activates caspases, a family of proteases essential for apoptosis, including caspase-3, -8, and -9. It also alters the balance of apoptosis-related proteins by increasing pro-apoptotic proteins like Bax and decreasing anti-apoptotic proteins like Bcl-2.

   • Autophagy: This process involves cells breaking down and recycling their own components. While normal autophagy helps cells survive, ivermectin induces excessive or “nonprotective” autophagy that starves the tumor from within, leading to cell death.

   • Mitochondrial Dysfunction:

     The drug causes a significant decrease in mitochondrial membrane potential ( ΔΨmcap delta cap psi sub mΔΨ𝑚) and promotes the accumulation of reactive oxygen species (ROS), which signals for cell death.

   • Pyroptosis: In some breast cancer cells, ivermectin induces pyroptosis, an inflammatory form of cell death. This occurs through the activation of purinergic receptors ( P2X4/P2X7cap P 2 cap X sub 4 / cap P 2 cap X sub 7

     𝑃2𝑋4/𝑃2𝑋7 ) and the release of pro-inflammatory proteins that trigger an immune response against the tumor.

   • Cell Cycle Arrest: Ivermectin also induces cell cycle arrest, which can further contribute to apoptosis and inhibit tumor growth.

   Modulation of signaling pathways

   Ivermectin modulates multiple signaling pathways by affecting components of the Wnt/β-catenin pathway, suppressing Hippo pathway-related protein YAP1, and influencing purinergic signaling (P2X4/P2X7/Pannexin-1). These actions contribute to ivermectin’s ability to inhibit cancer cell proliferation and metastasis, and its role in promoting cell death through mechanisms like apoptosis and autophagy.

   Wnt/β-catenin Signaling

   • Inhibition: Ivermectin represses Wnt-β-catenin/TCF transcriptional responses, which are crucial for cancer progression, including cell differentiation and growth.

   • Mechanism: It can interfere with the Wnt pathway by binding to TELO2, a regulator of phosphatidylinositol 3-kinase-related kinases, or by downregulating Wnt5a/b ligands.

   Hippo Pathway (YAP1 Regulation)

   • Inhibition of Proliferation:

     Ivermectin inhibits proliferation by decreasing the expression of YAP1, a key protein in the Hippo pathway that regulates organ size and is associated with poor cancer prognosis.

   • Mechanism: By decreasing nuclear YAP1 expression, ivermectin prevents it from activating transcription factors (TEAD) that promote cell growth.

   Purinergic Signaling (Extracellular ATP)

   • Inflammatory Response:

     Ivermectin modulates the sensitivity of P2X4/P2X7/Pannexin-1 signaling to extracellular ATP, potentially leading to inflammation.

   • Cell Death:

     It can induce a non-apoptotic and inflammatory form of cancer cell death by stimulating ATP release and activating caspase-1 through these purinergic receptors.

   Other Pathways and Mechanisms

   • Programmed Cell Death:

     Ivermectin promotes programmed cell death, including apoptosis, autophagy, and pyroptosis, which can be mutually regulated.

   • Tumor Stem Cell Inhibition:

     It has been shown to inhibit tumor stem cells and reverse multidrug resistance.

   • Cell Cycle and Metabolism:

     Proteomic analysis indicates ivermectin may also impact pathways involved in cell-cycle progression, RNA metabolism, and translational machinery.

   Other mechanisms

   Beyond directly inhibiting cancer cells, ivermectin can also disrupt tumor growth through other effects.

   • Inhibits cancer stem cells: By suppressing specific genes, ivermectin can inhibit the self-renewal and growth of cancer stem cells, a major cause of tumor recurrence.

   • Reverses drug resistance: Ivermectin can act as a P-glycoprotein inhibitor, blocking the drug efflux pumps that cancer cells use to develop multidrug resistance to chemotherapy.

   • Prevents angiogenesis: It can inhibit the formation of new blood vessels, a process called angiogenesis, that tumors need for nutrients and oxygen.

Induces autophagy:

1. Ivermectin induces autophagy by blocking key signaling pathways, including the PAK1-AKT-mTOR and AMPK/mTOR pathways, thathere cells degrade damaged components, has been shown to have an anticancer effect by inhibiting tumor cell growth and promoting cell death in various cancer cell lines.

   Mechanism of Action

   • PAK1-AKT-mTOR Pathway:

     Ivermectin promotes the ubiquitination-mediated degradation of PAK1, a protein that normally activates the AKT-mTOR signaling pathway.

   • AMPK/mTOR Pathway:

     Ivermectin can activate AMP-activated protein kinase (AMPK), which inhibits the mTOR pathway, leading to increased autophagic flux.

   • Increased Autophagic Flux:

     By inhibiting these pathways, ivermectin promotes the formation of autophagosomes (double-membraned vesicles), which are the hallmark of autophagy.

   Cellular and Biological Effects

   • Anticancer Activity:

     The autophagy induced by ivermectin can have a cytostatic (growth-inhibiting) effect, contributing to its potential as an anticancer agent.

   • Cell Death:

     In some cases, ivermectin-induced autophagy can lead to a form of cell death known as autophagy-mediated cell death, especially in cancer cells like glioma.

   • Mitochondrial Autophagy:

     Ivermectin can also specifically induce mitochondrial autophagy, a process where damaged mitochondria are removed to maintain cellular energy balance.

   Applications and Potential

   • Cancer Treatment:

     Ivermectin’s ability to induce autophagy has opened up avenues for developing it as a potential therapeutic option for various cancers, including breast cancer, glioma, and lung adenocarcinoma.

   • Multipurpose Drug:

     This research highlights ivermectin’s potential as a multitargeted drug that can not only treat parasitic infections but also exhibit anticancer properties by manipulating cellular processes like autophagy.

Promotes pyroptosis:

1. Ivermectin has been shown to induce pyroptosis, a form of programmed cell death, in some cancer cells, particularly when used in combination with other agents. It can achieve this by activating caspase-1 activity and leading to the cleavage of gasdermin D (GSDMD), which forms pores in the cell membrane and results in cell death.

   How Ivermectin Promotes Pyroptosis

   1. Caspase-1 Activation:

      Ivermectin can activate caspase-1, an enzyme that plays a critical role in the pyroptosis pathway.

   2. GSDMD Cleavage:

      Activated caspase-1 then cleaves GSDMD, a protein that is central to pyroptosis.

   3. Pore Formation:

      Cleaved GSDMD forms pores in the cell membrane, leading to the release of cellular contents.

   4. Cell Lysis and Death:

      The formation of these pores causes inflammation and ultimately leads to the lysis (bursting) of the cell, a process known as pyroptotic cell death.

   Clinical Significance

   • Anti-tumor Potential:

     The induction of pyroptosis by ivermectin can contribute to its anti-tumor effects by promoting the programmed death of cancer cells.

   • Combination Therapy:

     When used in combination with other chemotherapy drugs, ivermectin shows enhanced anti-tumor effects and can help to reverse multidrug resistance in cancer cells, according to this study.

Reverses multidrug resistance

1. Ivermectin has been shown to reverse multidrug resistance (MDR) in cancer cells by inhibiting the expression and function of P-glycoprotein (P-gp) and other ABC transporters, which pump drugs out of the cell. By reducing P-gp activity, ivermectin increases the intracellular concentration of chemotherapy drugs like paclitaxel and vincristine, making them more effective against drug-resistant cancer cells.

   Mechanisms of action

   • Inhibition of P-gp:

     Ivermectin directly interacts with P-gp, a key transporter involved in drug efflux, reducing its expression and activity.

   • Increased drug accumulation:

     By inhibiting P-gp, ivermectin allows more chemotherapy drugs to accumulate within cancer cells, increasing their therapeutic effect.

   • Synergistic effects:

     Ivermectin often demonstrates an additive or synergistic effect when combined with chemotherapy drugs, enhancing their ability to kill cancer cells.

   Implications for cancer treatment

   • Overcoming resistance:

     Ivermectin shows promise as a supportive therapy to help overcome resistance to conventional chemotherapy.

   • Enhanced efficacy:

     By sensitizing cancer cells to existing drugs, ivermectin can enhance the effectiveness of chemotherapy.

   • Reduced toxicity:

     In some cases, the combined treatment with ivermectin can lead to reduced overall toxicity associated with chemotherapy, according to a study on ScienceDirect.com.

Disrupts mitochondrial function:

1. Ivermectin disrupts mitochondrial function by decreasing mitochondrial membrane potential, inhibiting respiration and ATP production, and promoting the accumulation of reactive oxygen species (ROS). This mitochondrial dysfunction can lead to oxidative stress, DNA damage, and apoptosis (programmed cell death), contributing to its potential anti-cancer effects.

   Mechanisms of Mitochondrial Disruption:

   • Reduced Mitochondrial Membrane Potential:

     Ivermectin causes a significant decrease in the mitochondrial membrane potential (ΔΨmcap delta cap psi mΔΨ𝑚).

   • Inhibited Mitochondrial Respiration and ATP Production:

     It inhibits mitochondrial respiration and the production of adenosine triphosphate (ATP), the main energy currency of the cell.

   • Increased ROS Production:

     Ivermectin can induce the accumulation of intracellular reactive oxygen species (ROS) within cells.

   • Ivermectin-Induced Apoptotic Cell Death in Human SH-SY5Y Cells ...

     Ivermectin (IVM) induces mitochondrial dysfunction and activates the mitochondrial apoptotic pathway in human SH-SY5Y cells. (A) c...

     National Institutes of Health (NIH) | (.gov)

   • Ivermectin induces apoptosis of esophageal squamous cell ...

     Dec 7, 2021 — Ivermectin mediates mitochondrial dysfunction of ESCC cells. Intracellular ROS, which are predominantly derived from th...

     National Institutes of Health (NIH) | (.gov)

   Consequences of Mitochondrial Disruption:

   • Oxidative Stress:

     The accumulation of ROS can lead to oxidative stress and damage to cellular components, including DNA.

   • Induction of Apoptosis:

     The mitochondrial dysfunction and oxidative stress induced by ivermectin can trigger the mitochondrial apoptotic pathway, leading to programmed cell death.

   • Inhibition of Cell Growth:

     The disruption of mitochondrial function contributes to ivermectin’s ability to inhibit the growth and proliferation of cancer cells.

   Reversal of Effects:

   • The addition of mitochondrial stimulants like acetyl-L-carnitine (ALCAR) or antioxidants such as N-acetyl-L-cysteine (NAC) can reverse the ivermectin-induced mitochondrial dysfunction and protect cells from its effects.

   Generates reactive oxygen species (ROS)

   Scientific studies have shown that ivermectin can induce the generation of reactive oxygen species (ROS) in various cells, particularly at higher concentrations. This increase in ROS can lead to oxidative stress and cellular damage, which is a key part of its cytotoxic (cell-killing) effect against certain parasites and cancer cells.

   The generation of ROS is linked to several of ivermectin’s observed effects:

   • Mitochondrial dysfunction: Ivermectin disrupts the function of mitochondria, the primary source of cellular ROS. This leads to an overproduction of ROS, which in turn causes mitochondrial damage and triggers apoptosis (programmed cell death).

   • Antiparasitic action: In parasites like Leishmania and Giardia, ivermectin increases intracellular ROS levels. This oxidative stress contributes to DNA damage and cell death in the parasite, even in organisms that lack conventional mitochondria.

   • Anticancer properties: Ivermectin is being researched for its potential anticancer effects, and the generation of ROS is a central mechanism. The drug can induce mitochondrial apoptosis in cancer cells, increasing ROS production and shifting the balance of pro-apoptotic and anti-apoptotic proteins, such as Bax and Bcl-2.

   • Synergy with other treatments: In some cancer studies, ivermectin’s ability to induce ROS production has been shown to work synergistically with other chemotherapeutic agents that also induce oxidative stress.

   • Reversible effects: The role of ROS in ivermectin’s action is supported by experiments using antioxidants like N-acetyl-L-cysteine (NAC). When co-administered with NAC, the ivermectin-induced accumulation of ROS and the resulting cell death can be reversed or blocked.

Inhibits angiogenesis

1. Research shows that ivermectin can generate reactive oxygen species (ROS) in certain cell types, particularly cancer cells and parasites. The resulting oxidative stress is a key mechanism behind many of ivermectin’s observed cytotoxic effects.

   Mechanism of ROS generation by ivermectin

   Ivermectin’s effect on ROS production is dependent on the specific cell type and the drug concentration. Studies in both parasites and cancer cells have revealed several mechanisms through which ivermectin increases ROS levels:

   • Mitochondrial dysfunction: Ivermectin disrupts the normal function of the mitochondria, the primary source of cellular ROS. In numerous cancer and parasite cells, this leads to an increase in both total intracellular and mitochondrial-specific ROS.

   • Chloride ion influx: In leukemia and parasite cells, ivermectin activates chloride ion channels, causing an influx of chloride into the cell. This increase in intracellular chloride concentrations is functionally linked to a rise in ROS generation.

   • Inhibition of protective pathways: Some research suggests that ivermectin can suppress antioxidant defenses. For instance, studies have shown that it can decrease levels of glutathione, the body’s major antioxidant, further contributing to oxidative stress.

   • P2X receptors: In certain cancer cells, ivermectin has been shown to promote ROS release via purinergic P2X4 and P2X7 receptors, which then activate the NLRP3 inflammasome, triggering cell death pathways.

   Role of ROS in ivermectin’s effects

   The generation of excessive ROS is not an isolated effect but a central part of how ivermectin causes harm to target cells.

   • Cell death (apoptosis and necrosis): High levels of ROS can induce programmed cell death (apoptosis) by damaging cellular components like DNA, lipids, and proteins. The pro-apoptotic effects of ivermectin can be reversed by adding antioxidants like N-acetyl-L-cysteine (NAC).

   • Anticancer activity: Cancer cells are often more metabolically active and susceptible to oxidative stress than normal cells. Because of this vulnerability, ivermectin’s ability to generate ROS can preferentially kill cancer cells while sparing healthy ones, especially in leukemic and colorectal cancer cells.

   • Anti-parasitic activity: In parasites like Giardia lamblia, which lack conventional mitochondria and are highly susceptible to oxygen, ivermectin-induced ROS cause significant oxidative damage and cell death.

   It is important to note that the specific mechanisms and consequences of ivermectin-generated ROS can differ depending on the organism and cell type..

Targets cancer stem cells (CSCs)

Scientific studies, primarily at the preclinical stage, suggest that ivermectin can target and inhibit cancer stem cells (CSCs) across various types of cancer. This occurs through several mechanisms, including the inhibition of signaling pathways and the suppression of “stemness” genes.

1. Mechanisms of targeting cancer stem cells

   • Inhibition of the Akt/mTOR pathway: The Akt/mTOR pathway is crucial for cell growth and survival, and its overactivation is linked to cancer cell proliferation. Ivermectin blocks this pathway by promoting the degradation of the protein PAK1, which induces autophagy and apoptosis (cell death) in cancer cells. This process weakens the CSCs, making them more susceptible to treatment.

   • Suppression of stemness genes: Genes like NANOG, SOX2, and OCT4 are essential for maintaining the self-renewal and pluripotency characteristics of stem cells. Research in breast cancer and hepatocellular carcinoma (HCC) has shown that ivermectin significantly reduces the expression of these genes, effectively disrupting the stem-like properties of CSCs.

   • Targeting the Wnt/β-catenin pathway: Aberrant activation of the Wnt signaling pathway is frequently found in CSCs and drives tumor progression. Ivermectin can inhibit this pathway, which is associated with CSCs, reducing their proliferation and inducing apoptosis in certain cancer cells, such as colorectal cancer.

   • Synergy with chemotherapy: Some studies have found that ivermectin preferentially inhibits CSC-rich populations over bulk tumor cells. This suggests that combining ivermectin with traditional chemotherapy could overcome treatment resistance, which is often caused by resilient CSCs.

   Evidence for CSC targeting

   • Breast cancer: Studies on triple-negative breast cancer (TNBC) cell lines found that ivermectin preferentially killed CSC-enriched populations (identified by specific protein markers like CD44+/CD24-) and downregulated key “stemness” genes.

   • Hepatocellular carcinoma (HCC): In preclinical studies on HCC, ivermectin was found to inhibit the growth and colony-forming ability of stem-like cells and reduce the expression of CSC markers like NANOG, SOX2, and OCT4.

   • Other cancers: Ivermectin has also been shown to inhibit CSC activity in other cancers, including glioblastoma and osteosarcoma.

   Clinical trials and future outlook

   Despite promising preclinical evidence, research on ivermectin’s use as a cancer treatment is still in early stages. It is currently being explored through repurposing, a strategy that tests existing, approved drugs for new applications.

   • A Phase II clinical trial is underway to investigate the use of ivermectin in combination with the immunotherapy drug pembrolizumab for treating metastatic TNBC.

Modulates multiple signaling pathways

1. Ivermectin is known to modulate multiple signaling pathways,

   a characteristic particularly relevant in its investigation as a potential anticancer drug. While its traditional use is based on activating chloride channels in invertebrates, researchers have identified additional mechanisms in mammalian cells, including the regulation of cell proliferation, death, and energy metabolism. The broad-spectrum effects of ivermectin on these pathways make it a promising candidate for drug repurposing.

   Key signaling pathways modulated by ivermectin include:

   • Akt/mTOR pathway: In various cancers, ivermectin inhibits this pathway, leading to programmed cell death (apoptosis) and a process of cellular recycling known as autophagy. It does so by increasing the ubiquitination-mediated degradation of p21-activated kinase 1 (PAK1), a kinase upstream of Akt.

   • Wnt/βbeta𝛽-catenin pathway: This pathway regulates cell proliferation and is often overactive in many cancers. Ivermectin acts as a blocker of Wnt/

   • βbeta𝛽-catenin signaling, inhibiting the transcriptional responses that promote tumor growth. It achieves this by binding to the protein TELO2, which then disrupts the Wnt/βbeta𝛽-catenin signaling cascade.

   • Hippo/YAP1 pathway: The Hippo signaling pathway controls organ size and cell proliferation. Ivermectin inhibits the downstream protein Yes-associated protein 1 (YAP1), leading to tumor growth suppression in cancers such as gastric and liver cancer.

   • NF-κkappa𝜅B pathway: Ivermectin has been shown to inhibit the NF.

   • κkappa𝜅B signaling pathway, which is linked to inflammatory responses and cancer progression. In multiple myeloma cells, this inhibition induces apoptosis by reducing the expression and phosphorylation of NF-κkappa𝜅B proteins. The anti-inflammatory effect also extends to blocking TLR4 signaling and reducing cytokine production.

   • MAPK pathway: Ivermectin has been observed to inhibit the mitogen-activated protein kinase (MAPK) pathway by inactivating PAK1. This modulation contributes to its effects on cell death in various cancers, including nasopharyngeal carcinoma.

   • STAT3 pathway: Ivermectin can also inhibit the STAT3 signaling pathway, which plays a role in cytokine signaling and cell proliferation. It decreases the activity of STAT3 by suppressing PAK1, which is part of the signaling complex that activates IL-6 transcription and can contribute to cytokine storms.

   • DNA damage repair pathways: In prostate cancer, ivermectin targets proteins involved in DNA repair pathways. Specifically, it can bind to Ku70/Ku80, which are critical for non-homologous end joining (NHEJ), and downregulate homologous recombination (HR) genes. This dual inhibition can induce “synthetic lethality” by overwhelming the cancer cell’s ability to repair DNA.

   Inhibits PAK1 kinase

   P-21-activated kinase 1 (PAK1) is an oncogenic kinase often overexpressed in cancer cells. Ivermectin promotes the degradation of PAK1, which leads to the inhibition of downstream pathways like Akt/mTOR.

Epigenetic regulation

1. Ivermectin influences epigenetic regulation, particularly in cancer cells, by interacting with proteins involved in modifying the expression of certain genes. This activity has been explored in preclinical studies of its potential as a repurposed anti-cancer drug.

   Epigenetic mechanisms targeted by ivermectin

   Interaction with the SIN3 complex

   • Ivermectin acts as a “small-molecule mimetic” of the SIN3-interaction domain (SID).

   • It binds to the PAH2 motif of the SIN3A and SIN3B proteins, which are epigenetic regulators often deregulated in cancer.

   • The SIN3 complex controls the expression of transcription factors associated with stem cell pluripotency, such as NANOG and SOX2. By disrupting this complex, ivermectin can reduce the expression of these genes and inhibit the self-renewal capacity of cancer stem-like cells.

   Regulation of histone deacetylases (HDACs)

   • Ivermectin has been shown to reduce the expression of histone deacetylase 5 (HDAC5).

   • HDAC5 promotes inflammation by activating the transcription factor NF-κB.

   • The downregulation of HDAC5 is consistent with research suggesting that ivermectin has anti-inflammatory properties.

   DNA methylation

   • Research in aquatic organisms has shown that the related compounds, avermectins (AVMs), can cause global DNA hypomethylation.

   • This is linked to changes in the expression of DNA methyltransferases (DNMTs), the enzymes that add methyl groups to DNA.

   • Molecular docking studies also suggest that ivermectin can interact directly with the major groove of DNA, potentially influencing DNA methylation.

   Non-coding RNAs

   • Studies have explored how ivermectin affects gene expression and drug resistance by influencing non-coding RNAs, particularly microRNAs (miRNAs).

   • For example, ivermectin inhibits the RNA helicase DDX23, which promotes the production of miR-21. miR-21 is linked to tumor progression, and inhibiting it may also reduce cancer cell proliferation.

   Modulation of multidrug resistance

   • Some cancer cells develop resistance to chemotherapy by overexpressing the drug efflux pump P-glycoprotein (P-gp), which is encoded by the MDR1 gene.

   • Ivermectin can inhibit P-gp activity and block its expression by interfering with the EGFR/ERK/Akt/NF-κB signaling pathway.

   • This can increase the concentration of chemotherapy drugs inside cancer cells and reverse drug resistance.

   Inhibits RNA helicase activity

   Ivermectin inhibits the activity of viral RNA helicases, specifically targeting the NS3 helicase in flaviviruses like Yellow Fever Virus (YFV) and also exhibiting potential inhibitory effects on the SARS-CoV-2 helicase. This mechanism contributes to ivermectin’s broad-spectrum antiviral properties, as helicases are essential for viral replication.

   How ivermectin inhibits RNA helicases:

   Specific Targeting:

   • Ivermectin has been shown to directly bind to and inhibit the activity of the NS3 helicase, a crucial enzyme in the replication cycle of flaviviruses.

   • Antiviral Mechanism:

     By inhibiting the helicase, ivermectin disrupts the viral RNA synthesis process, which is critical for the virus to replicate within the host cell.

   • Broader Impact:

     This anti-helicase activity is one of several mechanisms by which ivermectin exhibits its antiviral effects against various RNA viruses, including Zika, dengue, and SARS-CoV-2.

   Examples of ivermectin’s anti-helicase action:

   • Flaviviruses:

     Ivermectin is a potent inhibitor of YFV replication and also affects other flaviviruses, such as dengue, Japanese encephalitis, and tick-borne encephalitis viruses, by targeting their NS3 helicase activity.

   • SARS-CoV-2:

     In silico studies have revealed that ivermectin can bind to the SARS-CoV-2 helicase complex, which could provide an additional pathway for its potential inhibition of the virus’s replication.

Enhances immunogenic cell death (ICD)

1. Ivermectin has been shown to enhance immunogenic cell death (ICD) in cancer, converting “cold” tumors into “hot” ones by inducing an immune response and increasing T-cell infiltration. It achieves this by modulating the ATP/P2X4/P2X7 axis and selectively targeting immunosuppressive cells, which synergizes with immune checkpoint inhibitors to limit tumor growth and improve outcomes in preclinical models, particularly in breast cancer.

   How Ivermectin Induces ICD

   • Modulates Immune Cells:

     Ivermectin acts as an allosteric modulator of the ATP/P2X4/P2X7 axis, which is involved in both cancer and immune cells.

   • Targets Immunosuppressive Cells:

     It selectively targets and modulates immunosuppressive populations, such as myeloid cells and regulatory T cells (Tregs), to enhance the anti-tumor immune response.

   • Increases T-Cell Infiltration:

     Ivermectin can recruit T cells into the tumor, a key characteristic of “hot” tumors that respond better to immunotherapy.

   • Promotes ICD Markers:

     In some studies, ivermectin enhances the ICD process by upregulating Cd8a and increasing the release of High Mobility Group Box 1 (HMGB1) in tumor tissues.

   Synergy with Other Therapies

   • Immune Checkpoint Blockade:

     Ivermectin’s ability to convert cold tumors to hot makes it a rational partner with immune checkpoint inhibitors, leading to synergistic activity in controlling tumor growth and potentially achieving complete responses in preclinical studies.

   • Combination with TLR Agonists:

     When combined with TLR7/8 agonists like resiquimod (R848) and encapsulated in a nanoemulsion, ivermectin has shown augmented antitumor activity by increasing ICD markers.

   Overall Impact

   • Converting Cold Tumors to Hot:

     Ivermectin’s primary role in cancer therapy is its ability to transform tumors with low immune cell infiltration (cold tumors) into those with significant immune cell activity (hot tumors).

   • Dual Action:

     It possesses both immunomodulatory and ICD-inducing effects, making it a promising candidate for combination therapies to improve treatment outcomes for various cancers.

Inhibits epithelial-mesenchymal transition (EMT)EMT

1. Ivermectin (IVM) inhibits epithelial-mesenchymal transition (EMT), particularly in endocrine-resistant breast cancer cells by suppressing the Wnt signaling pathway, and also in other cancer types by affecting the Wnt/β-catenin/FAK signaling pathway. This inhibition of EMT reduces cancer cell migration and metastasis, making ivermectin a potential therapeutic agent for treating and preventing cancer.

   Mechanism of Action

   • Wnt Signaling Pathway:

     Ivermectin suppresses the Wnt signaling pathway, which is a key driver of EMT in various cancers, including endocrine-resistant breast cancer.

   • Suppression of Metastasis:

     By inhibiting EMT, ivermectin prevents cancer cells from becoming invasive and metastatic, thereby reducing the spread of the tumor.

   • Inhibition of Specific Pathways:

     In addition to Wnt signaling, ivermectin also inhibits other metastasis-related signaling pathways, such as the Wnt/β-catenin/integrin β1/FAK pathway, which are crucial for cell migration and invasion.

   Therapeutic Potential

   • Cancer Treatment:

     Research suggests that ivermectin’s ability to inhibit EMT makes it a potential therapeutic agent for preventing and treating tumor metastasis in various cancer types, such as breast and pancreatic cancer.

   • Combination Therapy:

     Ivermectin can be used alone or in combination with other chemotherapeutic drugs, such as gemcitabine, to enhance treatment effectiveness.

   • Repurposing an Old Drug:

     The anti-EMT effects of ivermectin highlight its potential repurposing as an anticancer drug.