In a follow-up paper, these researchers found that the NLRP3 inflammasome complex negatively regulated TLR4-TRIF-mediated autophagy by activating caspase-1-induced TRIF cleavage in response to PrP106-126 stimulation.

It consists of three main components : an apoptosis associated speck like protein containing a CARD (caspase activation and recruitment domain) (ASC), which functions as a central adaptor protein; an inflammatory caspase, caspase-1, and a pattern recognition receptor (PRR) protein, NLRP3 (nucleotide binding domain (NOD)-like receptor protein 3).

It consists of three main components : an apoptosis associated speck like protein containing a CARD (caspase activation and recruitment domain) (ASC), which functions as a central adaptor protein; an inflammatory caspase, caspase-1, and a pattern recognition receptor (PRR) protein, NLRP3 (nucleotide binding domain (NOD)-like receptor protein 3).

Tau monomers and oligomers could therefore activate the NLRP3 inflammasome, and subsequent injection with fibrillar Abeta containing brain homogenates could induce tau seeding and pathology.

Furthermore, NLRP3 inflammasome-active microglia lead to neuronal cell death in a murine MPTP induced PD model, with KO of NLRP3 being found to protect against dopaminergic neuronal loss in a similar toxin based model, further emphasising the NLRP3 inflammasome 's role in neurodegeneration.

Furthermore, NLRP3 inflammasome-active microglia lead to neuronal cell death in a murine MPTP induced PD model, with KO of NLRP3 being found to protect against dopaminergic neuronal loss in a similar toxin based model, further emphasising the NLRP3 inflammasome 's role in neurodegeneration.

Indirect inhibition of NLRP3 inflammasome activation in 3 x TgAD mice using the fenamate non steroidal anti-inflammatory drug, mefanamic acid, completely abrogated the AD related neuroinflammation, with levels of IL-1beta expression and microglial activation reduced to wild-type levels.

Direct inhibition of the NLRP3 inflammasome with the small molecule inhibitor, MCC950, also known as CRID3, improved cognitive function and reduced Abeta accumulation, as well as promoting Abeta clearance in APP and PS1 mice (XREF_FIG).

Direct inhibition of the NLRP3 inflammasome with the small molecule inhibitor, MCC950, also known as CRID3, improved cognitive function and reduced Abeta accumulation, as well as promoting Abeta clearance in APP and PS1 mice (XREF_FIG).

Direct inhibition of the NLRP3 inflammasome with the small molecule inhibitor, MCC950, also known as CRID3, improved cognitive function and reduced Abeta accumulation, as well as promoting Abeta clearance in APP and PS1 mice (XREF_FIG).

It would be interesting to explore whether NLRP3 inhibition, or the use of other immunosuppressants, could reduce the pathophysiology of HD.

Fyn kinase, in conjunction with CD36, regulates microglial uptake of aggregated alpha-synuclein thereby linking Fyn kinase and CD36 activity to NLRP3 driven inflammation.

This SOD1 (G93A)-mediated inflammation also involved ROS, ATP mediated P2X7 receptor activation, with attenuation by the NLRP3 specific inhibitor MCC950, strongly suggesting that the NLRP3 inflammasome plays an essential role in the process.

The ROS inhibitor, N-acetyl-l-cysteine (NAC), significantly reduced IL-1beta production, and blocked NLRP3 and ASC upregulation after exposure to PrP106-126 in murine microglia.

With the advent of reprogramming era, it was further highlighted that p53 loss promote dedifferentiation and reprogramming under favorable conditions.

Furthermore, p53 loss was found to trigger dedifferentiation of mature hepatocytes to pluripotent cells by the activation of SC marker Nestin, which remains suppressed in wild-type p53 bearing cells (XREF_FIG).

TP53 maintains homeostasis between self-renewal and differentiation depending on the cellular and developmental state and prevents the dedifferentiation and reprogramming of somatic cells to stem cells.

Loss or gain-of-function mutations in TP53 induce dedifferentiation and proliferation of SCs with damaged DNA leading to the generation of CSCs.

While wild type p53 suppresses inflammatory response by inhibiting the production of cytokines and antagonizing NF-kB activity, mutant p53 on the other hand enhances NF-kB activity in response to TNF-alpha and promotes inflammation (XREF_FIG).

Mutant p53 can itself disrupt the balance between stem cell proliferation and differentiation as well as sequester p63 or p73 thereby hindering apoptosis, augmenting proliferation, and driving chemoresistance and metastasis typical of cancer stem cells.

Mutant p53 mediated repression of p63 function can also modulate the expression of certain miRNAs involved in invasion and metastasis such as let-7i, miR-155, miR-205, miR-130b, and miR-27a (XREF_FIG).

Hence, loss of NUMB in breast cancer cells leads to decreased p53 levels and increased activity of NOTCH receptor which confers increased chemoresistance.

Mutant p53 and p63 complex can increase RAB coupling protein (RCP)-mediated recycling of cell surface growth promoting receptors.

This eliminates mitochondria associated p53 which would otherwise be activated by PINK1 to mediate suppression of Nanog (XREF_FIG).

Further, the human p53 isoform Delta133p53beta lacking the transactivation domain was observed to promote CSC features in breast cancer cell lines by expression of Sox2, Oct3/4, and Nanog in a Delta133p53beta dependent manner.

Acetylation of p53 at K373 by CBP and p300 leads to dissociation of HDM2 and TRIM24 and subsequent activation of p53 which in turn transcriptionally activates p21, miR-34a, and miR-145 (XREF_FIG).

Acetylation of p53 at K373 by CBP and p300 leads to dissociation of HDM2 and TRIM24 and subsequent activation of p53 which in turn transcriptionally activates p21, miR-34a, and miR-145 (XREF_FIG).

Mutant p53 implicate various context and tissue dependent mechanisms to promote cancer cell invasion and metastasis.

Various transcription factors such as NF-Y, SREBPs, ETS, and EGFR1 play crucial role in mutant p53 driven invasion and metastasis.

Mutant p53 implicate various context and tissue dependent mechanisms to promote cancer cell invasion and metastasis.

Various transcription factors such as NF-Y, SREBPs, ETS, and EGFR1 play crucial role in mutant p53 driven invasion and metastasis.

This suggests that acetylation at K320 and K373 can alter the structure of mutant p53 and restore wild type p53 functions.

Mutant p53 can also induce YAP and TAZ nuclear localization by interacting with SREBP and activating the mevalonate pathway.

Mutant p53 can also promote proliferation by inducing the REG-gamma proteosome pathway in association with p300 (XREF_FIG).

GOF mutant p53 can modify the tumor microenvironment and has been found to support chronic inflammation.

While wild type p53 suppresses inflammatory response by inhibiting the production of cytokines and antagonizing NF-kB activity, mutant p53 on the other hand enhances NF-kB activity in response to TNF-alpha and promotes inflammation (XREF_FIG).

This underscores the significance of PARP1 inhibitors (PARPi) to augment synthetic lethality in the context of mutant p53 mediated incapacitation of DNA repair (XREF_FIG).

In absence of AMPK, mitochondrial stress augments aerobic glycolysis, also called " Warburg effect " in tumor cells, which is promoted by mutant p53.

Several evidence demonstrate that mutant p53 promotes glycolysis and reprograms the cellular metabolism of cancer cells.

However, whether mutant p53 induced EMT trigger stemness properties in cancer cells, is still quite unexplored.

Gain-of function mutant p53 further promotes EMT and stemness phenotypes by activating genes regulating them.

Although these studies highlight that mutant p53 mediated EMT phenotype confer stemness in cancer cells, however, there is still a lot to explore in context of molecular mechanisms of mutant p53 driven stemness through activation of EMT genes.

While wild type p53 suppresses inflammatory response by inhibiting the production of cytokines and antagonizing NF-kB activity, mutant p53 on the other hand enhances NF-kB activity in response to TNF-alpha and promotes inflammation (XREF_FIG).

The sustained activation of NF-kB signaling by mutant p53 not only elevate inflammatory response but also protects the cancer cells from cytotoxic effects of tumor microenvironment by activating pro survival pathways.

Interaction of mutant p53 to SREBPs activates mevalonate pathway that promotes invasion in breast cancer cells (XREF_FIG).

Mutant p53 can also induce YAP and TAZ nuclear localization by interacting with SREBP and activating the mevalonate pathway.

Similarly, p53 activation by nutlin leads to transcriptional activation of p21 that cause cell cycle arrest and induces differentiation in human ESCs.

Additionally, TLR4 signaling can be limited by the tyrosine phosphatases SHP1 and SHP2.

A number of preclinical studies have demonstrated that TLR4 gene deficiency or inhibition ameliorated renal function, decreased histological damage and reduced inflammation, oxidative stress and cell death in different types of AKI.

Besides its effects targeting Nrf2, sulforaphane specifically suppresses oligomerization of TLR4 and decrease inflammatory response [XREF_BIBR].

Glucose induces TLR4 expression in podocytes and tubular cells and increases inflammation, renal injury and fibrosis in diabetes nephropathy, effects that were not observed in TLR4 deficient mice [XREF_BIBR].

The expression of TLR4 can be downregulated by TGF-beta and the anti-inflammatory cytokine IL-10.

On the other hand, IL-10, throughout miR-146b, reduces the expression of TLR4, MyD88, IRAK1 and TRAF6 [XREF_BIBR].

The expression of TLR4 can be downregulated by TGF-beta and the anti-inflammatory cytokine IL-10.

Specifically, TGF-beta inhibits TLR4 gene expression and promotes MyD88 degradation, thus decreasing downstream signaling [XREF_BIBR, XREF_BIBR].

Resveratrol, a natural phytoalexin, also reduced TLR4 expression and NFkappaB activation in macrophages and mice with LPS induced AKI [XREF_BIBR].

Therefore, the binding of TLR4 to Stx may have a protective role by sequestering the toxin, or a harmful role by being a direct receptor of Stx, increasing its toxicity.

Another study has reported that histones released from dying renal cells in AKI directly interact with TLR2 and TLR4.

The interaction between LPS and both systemic and renal TLR4 has been reported in SI-AKI [XREF_BIBR].

SOCS1 is induced upon receptor activation and modulates TLR4 through two mechanisms.

CD14 transfers LPS to MD-2, a beta-cup folded protein necessary for LPS mediated TLR4 dimerization.

Specifically, TGF-beta inhibits TLR4 gene expression and promotes MyD88 degradation, thus decreasing downstream signaling [XREF_BIBR, XREF_BIBR].

TLR4 mediated MyD88 dependent signaling pathway requires the initial interaction with the sorting adaptor TIRAP (TIR domain containing adapter protein), present in regions enriched with phosphatidylinositol 4,5-bisphosphate, such as lipid rafts [XREF_BIBR, XREF_BIBR].

Upon ligand binding, TLR4 homodimerizes and initiates intracellular signaling through two major downstream pathways : (1) from the plasma membrane, the MyD88 dependent pathway, which activates early NFkappaB activation and cytokines production, and (2) from the endosome, the MyD88 independent TRIF dependent pathway, which upregulates type I IFNs and a late phase NFkappaB activation [XREF_BIBR, XREF_BIBR] (XREF_FIG).

Moreover, TLR4 mediated expression of cell adhesion molecules (ICAM-1 and E-selectin) may contribute to renal leucocyte infiltration and renal injury in SI-AKI [XREF_BIBR, XREF_BIBR].

Additionally, TLR4 recognition of DAMPs in damaged tissues further contributes to local inflammation and fibrosis [XREF_BIBR].

Glucose induces TLR4 expression in podocytes and tubular cells and increases inflammation, renal injury and fibrosis in diabetes nephropathy, effects that were not observed in TLR4 deficient mice [XREF_BIBR].

In addition to these data, NOX4 collaborated with TLR4 mediated apoptosis in renal I/R [XREF_BIBR].

CD14 transfers LPS to MD-2, a beta-cup folded protein necessary for LPS mediated TLR4 dimerization.

CD14 plays a key role in LPS mediated TLR4 endocytosis [XREF_BIBR].

Additionally, TLR4 signaling can be limited by the tyrosine phosphatases SHP1 and SHP2.

A number of preclinical studies have demonstrated that TLR4 gene deficiency or inhibition ameliorated renal function, decreased histological damage and reduced inflammation, oxidative stress and cell death in different types of AKI.

Besides its effects targeting Nrf2, sulforaphane specifically suppresses oligomerization of TLR4 and decrease inflammatory response [XREF_BIBR].

Glucose induces TLR4 expression in podocytes and tubular cells and increases inflammation, renal injury and fibrosis in diabetes nephropathy, effects that were not observed in TLR4 deficient mice [XREF_BIBR].

The expression of TLR4 can be downregulated by TGF-beta and the anti-inflammatory cytokine IL-10.

On the other hand, IL-10, throughout miR-146b, reduces the expression of TLR4, MyD88, IRAK1 and TRAF6 [XREF_BIBR].

The expression of TLR4 can be downregulated by TGF-beta and the anti-inflammatory cytokine IL-10.

Specifically, TGF-beta inhibits TLR4 gene expression and promotes MyD88 degradation, thus decreasing downstream signaling [XREF_BIBR, XREF_BIBR].

Resveratrol, a natural phytoalexin, also reduced TLR4 expression and NFkappaB activation in macrophages and mice with LPS induced AKI [XREF_BIBR].

Therefore, the binding of TLR4 to Stx may have a protective role by sequestering the toxin, or a harmful role by being a direct receptor of Stx, increasing its toxicity.

Another study has reported that histones released from dying renal cells in AKI directly interact with TLR2 and TLR4.

The interaction between LPS and both systemic and renal TLR4 has been reported in SI-AKI [XREF_BIBR].

SOCS1 is induced upon receptor activation and modulates TLR4 through two mechanisms.

CD14 transfers LPS to MD-2, a beta-cup folded protein necessary for LPS mediated TLR4 dimerization.

Specifically, TGF-beta inhibits TLR4 gene expression and promotes MyD88 degradation, thus decreasing downstream signaling [XREF_BIBR, XREF_BIBR].

Upon ligand binding, TLR4 homodimerizes and initiates intracellular signaling through two major downstream pathways : (1) from the plasma membrane, the MyD88 dependent pathway, which activates early NFkappaB activation and cytokines production, and (2) from the endosome, the MyD88 independent TRIF dependent pathway, which upregulates type I IFNs and a late phase NFkappaB activation [XREF_BIBR, XREF_BIBR] (XREF_FIG).

TLR4 mediated MyD88 dependent signaling pathway requires the initial interaction with the sorting adaptor TIRAP (TIR domain containing adapter protein), present in regions enriched with phosphatidylinositol 4,5-bisphosphate, such as lipid rafts [XREF_BIBR, XREF_BIBR].

Moreover, TLR4 mediated expression of cell adhesion molecules (ICAM-1 and E-selectin) may contribute to renal leucocyte infiltration and renal injury in SI-AKI [XREF_BIBR, XREF_BIBR].

Additionally, TLR4 recognition of DAMPs in damaged tissues further contributes to local inflammation and fibrosis [XREF_BIBR].

Glucose induces TLR4 expression in podocytes and tubular cells and increases inflammation, renal injury and fibrosis in diabetes nephropathy, effects that were not observed in TLR4 deficient mice [XREF_BIBR].

In addition to these data, NOX4 collaborated with TLR4 mediated apoptosis in renal I/R [XREF_BIBR].

CD14 transfers LPS to MD-2, a beta-cup folded protein necessary for LPS mediated TLR4 dimerization.

CD14 plays a key role in LPS mediated TLR4 endocytosis [XREF_BIBR].

The activation of the A 1 AR promotes osteoclast differentiation reducing the MSC-osteoblast differentiation.

Interestingly, we found that knockdown of either MICAL2 or MRTF-A suppressed the activity of CDC42, whereas this effect was reversed by overexpression of either MICAL2 or MRTF-A.

Interestingly, we found that knockdown of either MICAL2 or MRTF-A suppressed the activity of CDC42, whereas overexpression of both induced the opposite effect (XREF_FIG).

The precise mechanism underlying the MICAL2 and MRTF-A-induced activation of CDC42 in gastric cancer cells requires further investigation.

Silencing of CDC42 markedly inhibits the migration and invasion of gastric cancer cells.

Interestingly, we found that knockdown of either MICAL2 or MRTF-A suppressed the activity of CDC42, whereas this effect was reversed by overexpression of either MICAL2 or MRTF-A.

Interestingly, we found that knockdown of either MICAL2 or MRTF-A suppressed the activity of CDC42, whereas overexpression of both induced the opposite effect (XREF_FIG).

Moreover, silencing of MRTF-A inhibited the CDC42 activation induced by overexpression of MICAL2.

In this study, we found that knockdown of MRTF-A prevented the upregulation of CDC42 activation in the MICAL2 overexpressing cells.

Neonatal mice deficient in TLR4 have decreased LGR5+ stem cell proliferation and crypt fission compared to wild type mice.

Neonatal mice deficient in TLR4 have markedly diminished LGR5+ stem cell proliferation and diminished crypt fission.

Low dose, high MW endogenous HA binding to TLR4 may preferentially promote PGE2 production, whereas high dose low MW exogenous HA or LPS or LTA binding to TLR4 may preferentially promote CXCL12 production.

In contrast, TLR4 activation by LMW-HA requires a TLR4 and MD2 complex but is independent of CD14 and LPS binding protein.

TLR4 activation by LPS requires a TLR4 and MD2 complex, LPS binding protein, and CD14 which delivers LPS to the TLR4 and MD2 complex.

This may be the product of endogenous HAs of different molecular weights binding separately to CD44 and TLR4 or it may be the product of HA binding to a CD44 and TLR4 complex.

Hyaluronic acid binding to TLR4 in pericryptal macrophages results in cyclooxygenase2- dependent PGE 2 production, which transactivates EGFR in LGR5+ crypt epithelial stem cells leading to increased proliferation.

Among the PAMPs are lipoteichoic acid (LTA), a component of gram positive bacteria that binds TLR2, and LPS, a component of gram negative bacteria that binds TLR4.

Low dose, high MW endogenous HA binding to TLR4 may preferentially promote PGE2 production, whereas high dose low MW exogenous HA or LPS or LTA binding to TLR4 may preferentially promote CXCL12 production.

Although both LMW-HA and LPS bind to TLR4, the results of TLR4 activation by LMW-HA and LPS are not identical.

HA binds to CD44, TLR2, TLR4, the receptor for HA mediated motility (RHAMM), layilin, lymphatic vessel endothelial HA receptor- 1 (LYVE-1), and HA receptor for endocytosis.

Low dose, high MW endogenous HA binding to TLR4 may preferentially promote PGE2 production, whereas high dose low MW exogenous HA or LPS or LTA binding to TLR4 may preferentially promote CXCL12 production.

The presence of CD44 also enhances the effects of HA binding to TLR4 although the presence of CD44 is not required for HA activation of TLR4.

EGFR can activate beta-catenin via the receptor tyrosine kinase-PI3K-Akt pathway.

Although the evidence suggests that EGFR activation in response to TLR4 signaling is mediated by PGE2, it is also possible that TLR4 signaling promotes EGFR activation through the production of amphiregulin, epiregulin or other EGFR ligands.

Administration of exogenous TLR2 or TLR4 agonists activates TLR2 and TLR4 on pericryptal macrophages inducing CXCL12 production with migration of cyclooxygenase2 expressing mesenchymal stem cells from the lamina propria of the villi to a site adjacent to LGR5+ epithelial stem cells.

In contrast to wound repair, where inflammation accompanies enhanced epithelial proliferation driven by TLR2 and TLR4 activation, in intestinal growth TLR4 activation promotes epithelial proliferation in the absence of inflammation.

This suggests that TLR2 and TLR4 signaling driven by PAMPs from commensal bacteria promotes epithelial proliferation during wound repair in the colon.

Administration of exogenous TLR2 or TLR4 agonists activates TLR2 and TLR4 on pericryptal macrophages inducing CXCL12 production with migration of cyclooxygenase2 expressing mesenchymal stem cells from the lamina propria of the villi to a site adjacent to LGR5+ epithelial stem cells.

TLR4 activation by LPS requires a TLR4 and MD2 complex, LPS binding protein, and CD14 which delivers LPS to the TLR4 and MD2 complex.

TLR4 activation by LPS and LMW-HA require different accessory molecules.

Although both LMW-HA and LPS bind to TLR4, the results of TLR4 activation by LMW-HA and LPS are not identical.

In this pathway, TLR4, which is usually associated with innate immunity, is activated not by the microbial product LPS, but by HA, a host molecule.

In human biliary carcinoma cells in vitro, addition of LPS initiates a positive feedback loop of TLR4 activation, PGE2 production through COX-2 and EGFR activation.

A study of pulmonary injury induced by intratracheal bleomycin demonstrates the role of HA activation of TLR4 in sterile injury.

Taken together these studies addressing the cellular location of the TLR4 signaling that drives growth and wound repair and the nature of the relevant TLR4 ligand suggest that HA activation of myeloid TLR4 mediates intestinal and colonic growth and wound repair.

This suggests that TLR4 activation by endogenous HA promotes healing in DSS colitis.

TLR4 activation by HA also plays a role in wound repair.

There are suggestions that TLR4 is preferentially activated by the low MW form of HA.

TLR4 activation by HA drives LGR5+ epithelial stem cell proliferation and crypt fission in normal growth in the intestine and colon.

The presence of CD44 also enhances the effects of HA binding to TLR4 although the presence of CD44 is not required for HA activation of TLR4.

TLR2 and TLR4 activation by HA mediates wound repair in the bleomycin model of lung injury.

Wound repair mediated by HA activation of TLR2 and TLR4 is also seen in the lung.

In this pathway, TLR4, which is usually associated with innate immunity, is activated not by the microbial product LPS, but by HA, a host molecule.

Despite these suggestions there is good evidence that endogenous HA activates TLR4 and promotes growth even though most of the endogenous HA is in the high MW form.

TLR4 activation by HA also affects the immune response in ischemia- reperfusion injury in the kidney and in acute allograft rejection in a skin transplant model.

In the first pathway (XREF_FIG), intestinal and colonic growth is regulated by endogenous HA activating TLR4 on pericryptal macrophages resulting in the release of PGE2 which promotes LGR5+ stem cell proliferation, crypt fission and intestinal elongation.

Based on the growth studies, it is likely that EGFR activation by PGE2 is also the mechanism of the increased epithelial proliferation in the repair phase of DSS colitis.

In growth EGFR activation by PGE2 accounts for about 30% of LGR5+ cell proliferation.

Although the evidence suggests that EGFR activation in response to TLR4 signaling is mediated by PGE2, it is also possible that TLR4 signaling promotes EGFR activation through the production of amphiregulin, epiregulin or other EGFR ligands.

Mechanistically, LCZ696 prevents LPS induced activation of the TLR4 and Myd88 pathway and nuclear translocation of nuclear factor kappa-B (NF-kappaB) p65 factor.

The TLR4 signaling inhibitor, TAK-242, inhibited HUVEC IL-8 secretion in response to SS plasma by 85%.

Free heme released by hemolyzed red blood cells can bind to myeloid differentiation factor-2 (MD-2) and activate TLR4 pro inflammatory signaling on endothelium to promote vaso-occlusion and acute chest syndrome in murine models of SCD.

In addition, the thermal shift and co-immunoprecipitation assays revealed that oleuropein played an essential role in binding to the active sites of TLR4, as well as inhibiting TLR4 dimerization and suppressing the binding of TLR4 to MyD88.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

Thus, CAPE suppresses the interaction between NLRP3 and deubiquitinating enzymes, and enhances its interaction with a ubiquitin conjugating enzyme in vivo and in vitro, promoting NLRP3 ubiquitination.

Moreover, CAPE enhanced the binding of NLRP3 to ubiquitin molecules, promoted NLRP3 ubiquitination (XREF_FIG), and significantly blocked the formation of NLRP3 inflammasome, which were again reversed by rotenone (XREF_FIG).

CAPE Promotes NLRP3 Ubiquitination by Inhibiting ROS.

Moreover, CAPE enhanced the binding of NLRP3 to ubiquitin molecules, promoted NLRP3 ubiquitination (XREF_FIG), and significantly blocked the formation of NLRP3 inflammasome, which were again reversed by rotenone (XREF_FIG).

We found that CAPE decreased NLRP3 inflammasome activation in BMDMs and THP-1 cells and protected mice from colorectal cancer induced by AOM and DSS.

In conclusion, CAC can be prevented by CAPE induced NLRP3 inflammasome inhibition, highlighting CAPE as a potential candidate for reducing the risk of CAC in patients with inflammatory bowel disease.

Overall, the results indicate that activated NLRP3 in AOM and DSS mouse model is suppressed by CAPE.

To determine whether CAPE inhibits NLRP3 inflammasome in vivo, we assessed NLRP3 expression in the AOM and DSS mouse model by immunohistochemistry and western blotting.

Moreover, CAPE significantly inhibited the formation of ASC dimers and reduced the abundance of NLRP3 inflammasome complexes in a dose dependent manner (XREF_FIG).

We first investigated whether CAPE inhibits the activation of NLRP3 inflammasome induced by ATP and LPS in macrophages in vitro.

CAPE Decreases NLRP3 Inflammasome Activation in BMDMs and THP-1 Cells.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

However, CAPE did not affect NLRP3 or IL-1beta transcription, but instead enhanced NLRP3 binding to ubiquitin molecules, promoting NLRP3 ubiquitination, and contributing to the anti-tumor effect in the AOM and DSS mouse model.

As shown in XREF_FIG, LPS + ATP promoted the expression of NLRP3 and pro-IL-1beta in THP-1 cells; however, real-time PCR revealed that after treatment with CAPE for 12 h, mRNA levels of NLRP3 and IL-1beta in THP-1 cells were similar to control (XREF_FIG), indicating that CAPE does not affect the transcription of NLRP3 and IL-1beta.

As shown in XREF_FIG, LPS + ATP promoted the expression of NLRP3 and pro-IL-1beta in THP-1 cells; however, real-time PCR revealed that after treatment with CAPE for 12 h, mRNA levels of NLRP3 and IL-1beta in THP-1 cells were similar to control (XREF_FIG), indicating that CAPE does not affect the transcription of NLRP3 and IL-1beta.

Western blotting showed that CAPE significantly inhibited the increased protein levels of NLRP3, caspase-1, and IL-1beta in BMDMs and THP-1 cells after LPS and ATP stimulation (XREF_FIG).

Furthermore, CAPE significantly reduced the expression of NLRP3, cleaved caspase-1, and cleaved IL-1beta, which was restored by rotenone (XREF_FIG).

Moreover, CAPE decreased the mRNA levels of NLRP3, IL-1beta, IL-6, and TNF-alpha (XREF_FIG), increased the binding of NLRP3 to ubiquitin molecules and facilitated NLRP3 ubiquitination (XREF_FIG).

We then examined whether CAPE also reduces NLRP3 mRNA levels.

Altogether, these results indicate that CAPE reduces NLRP3 protein levels and suppresses NLRP3 activation in macrophages.

CAPE enhanced the interaction between NLRP3 and Cullin1 and decreased the interaction between NLRP3 and CSN5 in THP-1 cells in a time dependent manner (XREF_FIG).

CAPE enhanced the interaction between NLRP3 and Cullin1 and decreased the interaction between NLRP3 and CSN5 in THP-1 cells in a time dependent manner (XREF_FIG).

Moreover, CAPE suppressed the interaction between NLRP3 and CSN5 but enhanced that between NLRP3 and Cullin1 both in vivo and in vitro.

NLRP3 interacts with ASC and pro-caspase-1 to form an inflammasome.

Altogether, these results indicate that CAPE reduces NLRP3 protein levels and suppresses NLRP3 activation in macrophages.

Activated NLRP3 promotes pro-caspase-1 proteolysis into its active form, caspase-1 (p20), and then cleaves pro-IL-1beta and pro-IL-18 into their mature forms (IL-1beta and IL-18).

NLRP3 triggers innate immunity by activating caspase-1 and then cleaves immune and metabolic substrates, especially the pro inflammatory cytokine interleukin-1beta (IL-1beta), which induces inflammation and promotes tumor growth.

Moreover, NLRP3 inhibition was found to prevent CAC.

Altogether, our findings indicate that inhibition of NLRP3 inflammasome by CAPE prevents CAC.

NLRP3 triggers innate immunity by activating caspase-1 and then cleaves immune and metabolic substrates, especially the pro inflammatory cytokine interleukin-1beta (IL-1beta), which induces inflammation and promotes tumor growth.

Altogether, our findings demonstrate that CAPE prevents CAC by post-transcriptionally inhibiting NLRP3 inflammasome.

Caffeic Acid Phenethyl Ester Prevents Colitis Associated Cancer by Inhibiting NLRP3 Inflammasome.

In this study, we provide evidence that CAPE facilitates NLRP3 ubiquitination by inhibiting ROS in THP-1 cells and inhibits enteritis and tumor burden by inhibiting NLRP3 in an AOM and DSS mouse model.

We first investigated whether CAPE inhibits the activation of NLRP3 inflammasome induced by ATP and LPS in macrophages in vitro.

We first investigated whether CAPE inhibits the activation of NLRP3 inflammasome induced by ATP and LPS in macrophages in vitro.

Pharmacologic CREB1 inhibition dramatically reduced FOXA1 and B-catenin expression and dampened PDAC metastasis, identifying a new therapeutic strategy to disrupt cooperation between oncogenic KRAS and mutant p53 to mitigate metastasis.

Specifically, mutant p53 and CREB1 upregulate the pro metastatic, pioneer transcription factor, FOXA1, activating its transcriptional network while promoting Wnt and B-catenin signaling, together driving PDAC metastasis.

Furthermore, it blocked HMGB1 mediated TLR4 dependent signalling in vitro and circulating HMGB1 in vivo [XREF_BIBR].

We also briefly review the proposed use of TLR4 antagonists as antiviral treatments, including Eritoran, Resatorvid (CLI-095 and TAK242), and glycyrrhizin, as well as another compound, nifuroxazide, that interrupts TLR4 signalling.

TLR4 uses an accessory protein called MD2 for the recognition of LPS and viral proteins; MD2 initially binds to TLR4 within the cell and is also necessary for the correct trafficking of TLR4 to the cell surface [XREF_BIBR].

COVID-19 and Toll Like Receptor 4 (TLR4) : SARS-CoV-2 May Bind and Activate TLR4 to Increase ACE2 Expression, Facilitating Entry and Causing Hyperinflammation.

We can confidently extrapolate the above findings in Sections 8.1 and 8.2 from SARS-CoV-1 to SARS-CoV-2; hence, we propose that SARS-CoV-2 would activate TLR4 directly, probably via its spike protein binding to TLR4 (and/or MD2).

This can be extrapolated to SARS-CoV-2, where intracellularly, its M protein may be inducing TLR4 dependent TRAF3 independent IFN-beta production.

Hence, a possible model for the interaction of SARS-CoV-2 and TLR4 is outlined in Section 11 and the graphical abstract (XREF_FIG) in which SARS-CoV-2 may activate TLR4 in the heart and lungs to cause aberrant TLR4 signalling in favour of the proinflammatory MyD88 dependent (canonical) pathway rather than the alternative TRIF and TRAM dependent anti-inflammatory and interferon pathway.

Specifically, the disulphide form of HMGB1 stimulates TLR4, while extracellular HMGB1 can form complexes with DNA, RNA, other DAMP or PAMP molecules; the complexes are endocytosed via RAGE and transported to the endolysosomal system.

A review by Andersson et al. suggests that HMGB1 released as a DAMP or secreted by activated immune cells could activate both TLR4 and the receptor for advanced glycation end-products (RAGE) to generate proinflammatory cytokines [XREF_BIBR].

Moreover, HMGB1 and other DAMPS released from necrotic and lytic cells, as well as ambient LPS levels entering the lungs or released from opportunistic gram negative bacteria, can also activate TLR4, amplifying the already severe inflammation.

IL-18 is also induced by the NLRP3 inflammasome in the lungs and heart.

Inhibition of the NLRP3 inflammasome signalling pathway downstream of TLR4 attenuates LPS induced acute lung injury [XREF_BIBR, XREF_BIBR].

This raises the question, is it only ACE2 that the spike protein of SARS-CoV-2 binds to or is there also another receptor involved, such as TLR4 which is known to promote cardiac hypertrophy, myocardial inflammation, and fibrosis [XREF_BIBR - XREF_BIBR]?