PI3K is required for the physical interaction and functional inhibition of NF-κB by β-catenin in colorectal cancer cells

Aerobic exercise training engages the canonical wnt pathway to improve pulmonary function and inflammation in COPD

BACKGROUND

We studied whether the exercise improves cigarette smoke (CS) induced chronic obstructive pulmonary disease (COPD) in mice through inhibition of inflammation mediated by Wnt/β-catenin-peroxisome proliferator-activated receptor (PPAR) γ signaling.

METHODS

Firstly, we observed the effect of exercise on pulmonary inflammation, lung function, and Wnt/β-catenin-PPARγ. A total of 30 male C57BL/6J mice were divided into the control group (CG), smoke group (SG), low-intensity exercise group (LEG), moderate-intensity exercise group (MEG), and high-intensity exercise group (HEG). All the groups, except for CG, underwent whole-body progressive exposure to CS for 25 weeks. Then, we assessed the maximal exercise capacity of mice from the LEG, MEG, and HEG, and performed an 8-week treadmill exercise intervention. Then, we used LiCl (Wnt/β-catenin agonist) and XAV939 (Wnt/β-catenin antagonist) to investigate whether Wnt/β-catenin-PPARγ pathway played a role in the improvement of COPD via exercise. Male C57BL/6J mice were randomly divided into six groups (n = 6 per group): CG, SG, LiCl group, LiCl and exercise group, XAV939 group, and XAV939 and exercise group. Mice except those in the CG were exposed to CS, and those in the exercise groups were subjected to moderate-intensity exercise training. All the mice were subjected to lung function test, lung histological assessment, and analysis of inflammatory markers in the bronchoalveolar lavage fluid, as well as detection of Wnt1, β-catenin and PPARγ proteins in the lung tissue.

RESULTS

Exercise of various intensities alleviated lung structural changes, pulmonary function and inflammation in COPD, with moderate-intensity exercise exhibiting significant and comprehensive effects on the alleviation of pulmonary inflammation and improvement of lung function. Low-, moderate-, and high-intensity exercise decreased β-catenin levels and increased those of PPARγ significantly, and only moderate-intensity exercise reduced the level of Wnt1 protein. Moderate-intensity exercise relieved the inflammation aggravated by Wnt agonist. Wnt antagonist combined with moderate-intensity exercise increased the levels of PPARγ, which may explain the highest improvement of pulmonary function observed in this group.

CONCLUSIONS

Exercise effectively decreases COPD pulmonary inflammation and improves pulmonary function. The beneficial role of exercise may be exerted through Wnt/β-catenin-PPARγ pathway.

Neuroinflammation in Schizophrenia: The Key Role of the WNT/β-Catenin Pathway

Schizophrenia is a very complex syndrome involving widespread brain multi-dysconnectivity. Schizophrenia is marked by cognitive, behavioral, and emotional dysregulations. Recent studies suggest that inflammation in the central nervous system (CNS) and immune dysfunction could have a role in the pathogenesis of schizophrenia. This hypothesis is supported by immunogenetic evidence, and a higher incidence rate of autoimmune diseases in patients with schizophrenia. The dysregulation of the WNT/β-catenin pathway is associated with the involvement of neuroinflammation in schizophrenia. Several studies have shown that there is a vicious and positive interplay operating between neuroinflammation and oxidative stress. This interplay is modulated by WNT/β-catenin, which interacts with the NF-kB pathway; inflammatory factors (including IL-6, IL-8, TNF-α); factors of oxidative stress such as glutamate; and dopamine. Neuroinflammation is associated with increased levels of PPARγ. In schizophrenia, the expression of PPAR-γ is increased, whereas the WNT/β-catenin pathway and PPARα are downregulated. This suggests that a metabolic-inflammatory imbalance occurs in this disorder. Thus, this research’s triptych could be a novel therapeutic approach to counteract both neuroinflammation and oxidative stress in schizophrenia.

Possible actions of cannabidiol in obsessive-compulsive disorder by targeting the WNT/β-catenin pathway

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized by recurrent and distinctive obsessions and/or compulsions. The etiologies remain unclear. Recent findings have shown that oxidative stress, inflammation, and glutamatergic pathways play key roles in the causes of OCD. However, first-line therapies include cognitive-behavioral therapy but only 40% of the patients respond to this first-line therapy. Research for new treatment is mandatory. This review focuses on the potential effects of cannabidiol (CBD), as a potential therapeutic strategy, on OCD and some of the presumed mechanisms by which CBD provides its benefit properties. CBD medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. The activation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway and circadian rhythms dysregulation in OCD. Future prospective clinical trials could focus on CBD and its different and multiple interactions in OCD.

Cherry Polyphenol Extract Ameliorated Dextran Sodium Sulfate-Induced Ulcerative Colitis in Mice by Suppressing Wnt/β-Catenin Signaling Pathway

Ulcerative colitis (UC) is a chronic and nonspecific inflammatory disease of the colon and rectum, and its etiology remains obscure. Cherry polyphenols showed potential health-promoting effects. However, both the protective effect and mechanism of cherry polyphenols on UC are still unclear. This study aimed to investigate the potential role of the free polyphenol extract of cherry in alleviating UC and its possible mechanism of action. Our study revealed that the free polyphenol extract of cherry management significantly alleviated UC symptoms, such as weight loss, colon shortening, the thickening of colonic mucous layer, etc. The free polyphenol extract of cherry treatment also introduced a significant reduction in levels of malondialdehyde (MDA), myeloperoxidase (MPO) and nitric oxide (NO), while causing a significant elevation in levels of catalase (CAT), glutathione (GSH-Px), superoxide dismutase (SOD), as well as the downregulation of pro-inflammatory cytokines. This indicated that such positive effects were performed through reducing oxidative damage or in a cytokine-specific manner. The immunofluorescence analysis of ZO-1 and occludin proteins declared that the free polyphenol extract of cherry had the potential to prompt intestinal barrier function. The reduced expression levels of β-catenin, c-myc, cyclin D1 and GSK-3β suggested that the cherry extract performed its positive effect on UC by suppressing the Wnt/β-ctenin pathway. This finding may pave the way into further understanding the mechanism of cherry polyphenols ameliorating ulcerative colitis.

Lithium and Atypical Antipsychotics: The Possible WNT/β Pathway Target in Glaucoma

Glaucoma is a progressive neurodegenerative disease that represents the major cause of irreversible blindness. Recent findings have shown which oxidative stress, inflammation, and glutamatergic pathway have main roles in the causes of glaucoma. Lithium is the major commonly used drug for the therapy of chronic mental illness. Lithium therapeutic mechanisms remain complex, including several pathways and gene expression, such as neurotransmitter and receptors, circadian modulation, ion transport, and signal transduction processes. Recent studies have shown that the benefits of lithium extend beyond just the therapy of mood. Neuroprotection against excitotoxicity or brain damages are other actions of lithium. Moreover, recent findings have investigated the role of lithium in glaucoma. The combination of lithium and atypical antipsychotics (AAPs) has been the main common choice for the treatment of bipolar disorder. Due to the possible side effects gradually introduced in therapy. Currently, no studies have focused on the possible actions of AAPs in glaucoma. Recent studies have shown a down regulation of the WNT/β-catenin pathway in glaucoma, associated with the overactivation of the GSK-3β signaling. The WNT/β-catenin pathway is mainly associated with oxidative stress, inflammation and glutamatergic pathway. Lithium is correlated with upregulation the WNT/β-catenin pathway and downregulation of the GSK-3β activity. Thus, this review focuses on the possible actions of lithium and AAPs, as possible therapeutic strategies, on glaucoma and some of the presumed mechanisms by which these drugs provide their possible benefit properties through the WNT/β-catenin pathway.

High dose lithium chloride causes colitis through activating F4/80 positive macrophages and inhibiting expression of Pigr and Claudin-15 in the colon of mice

OBJECTIVE

Lithium chloride (LiCl) was a mood stabilizer for bipolar affective disorders and it could activate Wnt/β-catenin signaling pathway both in vivo and in vitro. Colon is one of a very susceptible tissues to Wnt signaling pathway, and so it would be very essential to explore the toxic effect of a high dose of LiCl on colon.

METHODS

C57BL/6 mice were injected intraperitoneally with 200 mg/kg LiCl one dose a day for 5 days to activate Wnt signal pathway in intestines. H&E staining was used to assess the colonic tissues of mice treated with high dose of LiCl. The expression of inflammation-associated genes and tight junction-associated genes in colons was measured using qPCR, Western blot and immunostaining methods. The gut microbiome was tested through 16S rDNA gene analysis.

RESULTS

The differentiation of enteroendocrine cells in colon was inhibited by treatment of 200 mg/kg LiCl. The F4/80 positive macrophages in colon were activated by high dose of LiCl, and migrated from the submucosa to the lamina propria. The expression of pro-inflammatory genes TNFα and IL-1β was increased in the colon of high dose of LiCl treated mice. Clostridium_sp_k4410MGS_306 and Prevotellaceae_UCG_001 were specific and predominant for the high dose of LiCl treated mice. The expression of IgA coding genes, Pigr and Claudin-15 was significantly decreased in the colon tissues of the high dose of LiCl treated mice.

CONCLUSION

200 mg/kg LiCl might cause the inflammation in colon of mice through activating F4/80 positive macrophages and inhibiting the expression of IgA coding genes in plasma cells and the expression of Pigr and Claudin-15 in colonic epithelial cells, providing evidences for the toxic effects of high dose of LiCl on colon.

Toward Colorectal Cancer Biomarkers: The Role of Genetic Variation, Wnt Pathway, and Long Noncoding RNAs

Colorectal cancer (CRC) is the third leading cause of death worldwide, comprising nearly 8% of cancer-related deaths per year. In South Korea, for example, CRC is the second most common cancer in men, and third in women. This study reports on the association of CRC with genetic variations in long noncoding RNAs, activators, and inhibitors of a cell proliferation pathway. Five normal colon mucosa tissue samples and their matched five-stage IV CRC samples were evaluated (dataset Gene Expression Omnibus accession: GSE50760). We identified more than 5000 differentially expressed genes (DEGs). The Wnt pathway had the greatest portion of DEGs, including activators, inhibitors, and associated long noncoding RNAs (lncRNAs), suggesting the importance of Wnt pathway in CRC. The following genes were aberrantly expressed: WIF1, SFRP4, CD82, WNT2, WNT3, WNT5A, HOTAIR, CRNDE, and UCA1. Notably, HOTAIR is known to silence WIF1, and WIF1 inhibits the Wnt ligands to negatively regulate the pathway. The lncRNA CRNDE positively regulates WNT5A, while UCA1 positively regulates WNT2 and WNT3. We note that HOTAIR was unable to silence WIF1. CRNDE and UCA1 were found to be upregulated, which may explain the high expression of the WIF1 targets. Furthermore, 10 single-nucleotide polymorphisms (SNPs) were identified in five of the candidate genes above. A possible novel SNP in CD82, chr11:44619242T > C, was predicted to introduce a ZBTB7A binding site. These SNPs are hypothesized to contribute to aberrant and discrepant regulation of the Wnt pathway in a context of CRC pathogenesis. These findings collectively inform future research on diagnostics and therapeutics innovation in CRC.

Potential role of cannabidiol in Parkinson's disease by targeting the WNT/β-catenin pathway, oxidative stress and inflammation

Parkinson's disease (PD) is a major neurodegenerative disease (ND), presenting a progressive degeneration of the nervous system characterized by a loss of dopamine in the substantia nigra pars compacta. Recent findings have shown that oxidative stress and inflammation play key roles in the development of PD. However, therapies remain uncertain and research for new treatment is of the utmost importance. This review focuses on the potential effects of using cannabidiol (CBD) as a potential therapeutic strategy for the treatment of PD and on some of the presumed mechanisms by which CBD provides its beneficial properties. CBD medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. Activation of the WNT/β-catenin could be associated with the control of oxidative stress and inflammation. Future prospective clinical trials should focus on CBD and its multiple interactions in the treatment of PD.

Lithium: a potential therapeutic strategy in obsessive-compulsive disorder by targeting the canonical WNT/β pathway

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized b-y recurrent and distinctive obsessions and/or compulsions. The etiologies remain unclear. Recent findings have shown that oxidative stress, inflammation, and the glutamatergic pathway play key roles in the causes of OCD. However, first-line therapies include cognitive-behavioral therapy but only 40% of the patients respond to this first-line therapy. Research for a new treatment is mandatory. This review focuses on the potential effects of lithium, as a potential therapeutic strategy, on OCD and some of the presumed mechanisms by which lithium provides its benefit properties. Lithium medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. The activation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway. Future prospective clinical trials could focus on lithium and its different and multiple interactions in OCD.

Cannabidiol and the Canonical WNT/β-Catenin Pathway in Glaucoma

Glaucoma is a progressive neurodegenerative disease which constitutes the main frequent cause of irreversible blindness. Recent findings have shown that oxidative stress, inflammation and glutamatergic pathway play key roles in the causes of glaucoma. Recent studies have shown a down regulation of the WNT/β-catenin pathway in glaucoma, associated with overactivation of the GSK-3β signaling. WNT/β-catenin pathway is mainly associated with oxidative stress, inflammation and glutamatergic pathway. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid derived from Cannabis sativa plant which possesses many therapeutic properties across a range of neuropsychiatric disorders. Since few years, CBD presents an increased interest as a possible drug in anxiolytic disorders. CBD administration is associated with increase of the WNT/β-catenin pathway and decrease of the GSK-3β activity. CBD has a lower affinity for CB1 but can act through other signaling in glaucoma, including the WNT/β-catenin pathway. CBD downregulates GSK3-β activity, an inhibitor of WNT/β-catenin pathway. Moreover, CBD was reported to suppress pro-inflammatory signaling and neuroinflammation, oxidative stress and glutamatergic pathway. Thus, this review focuses on the potential effects of cannabidiol, as a potential therapeutic strategy, on glaucoma and some of the presumed mechanisms by which this phytocannabinoid provides its possible benefit properties through the WNT/β-catenin pathway.

Inflammation and Wnt Signaling: Target for Immunomodulatory Therapy?

Wnt proteins comprise a large family of highly conserved glycoproteins known for their role in development, cell fate specification, tissue regeneration, and tissue homeostasis. Aberrant Wnt signaling is linked to developmental defects, malignant transformation, and carcinogenesis as well as to inflammation. Mounting evidence from recent research suggests that a dysregulated activation of Wnt signaling is involved in the pathogenesis of chronic inflammatory diseases, such as neuroinflammation, cancer-mediated inflammation, and metabolic inflammatory diseases. Recent findings highlight the role of Wnt in the modulation of inflammatory cytokine production, such as NF-kB signaling and in innate defense mechanisms as well as in the bridging of innate and adaptive immunity. This sparked the development of novel therapeutic treatments against inflammatory diseases based on Wnt modulation. Here, we summarize the role and function of the Wnt pathway in inflammatory diseases and focus on Wnt signaling as underlying master regulator of inflammation that can be therapeutically targeted.

Dimethyl fumarate protects against intestinal ischemia/reperfusion lesion: Participation of Nrf2/HO-1, GSK-3β and Wnt/β-catenin pathway

OBJECTIVE

Dimethyl fumarate (DMFU), a known Nrf2 activator, has proven its positive effect in different organs against ischemia/reperfusion (Is/Re) injury. Nevertheless, its possible impact to modulate intestinal Is/Re-induced injury has not been previously demonstrated before. Hence, this study aimed to investigate DMFU mechanistic maneuver against intestinal Is/Re.

METHODS

To accomplish this goal, Wistar rats were allocated into four groups; Sham-operated (SOP), intestinal Is/Re (1 h/6 h), and 14 days pre-treated DMFU (15 and 25 mg/kg/day, p.o).

RESULTS

The mechanistic maneuver divulged that DMFU safeguarded the intestine partly via amplifying the expression/content of Nrf2 along with enhancing its downstream, HO-1 expression/content. In addition, DMFU lessened GSK-3β expression/content accompanied by enriching β-catenin expression/content. The antioxidant action was affirmed by enhancing total antioxidant capacity, besides reducing MDA, iNOS, and its by-product, NOx. The DMFU action entailed anti-inflammatory character manifested by down-regulation of expression/content NF-κB with subsequent rebating the contents of TNF-α, IL-1β, and P-selectin, as well as MPO activity. Moreover, DMFU had anti-apoptotic nature demonstrated through enriching Bcl-2 level and diminishing that of caspase-3.

CONCLUSION

DMFU purveyed tenable novel protective mechanisms and mitigated events associated with intestinal Is/Re mischief either in the lower or the high dose partly by amending of oxidative stress and inflammation through the modulation of Nrf2/HO-1, GSK-3β, and Wnt/β-catenin pathways.

Parkinson's Disease: Potential Actions of Lithium by Targeting the WNT/β-Catenin Pathway, Oxidative Stress, Inflammation and Glutamatergic Pathway

Parkinson's disease (PD) is one of the major neurodegenerative diseases (ND) which presents a progressive neurodegeneration characterized by loss of dopamine in the substantia nigra pars compacta. It is well known that oxidative stress, inflammation and glutamatergic pathway play key roles in the development of PD. However, therapies remain uncertain and research for new treatment is mandatory. This review focuses on the potential effects of lithium, as a potential therapeutic strategy, on PD and some of the presumed mechanisms by which lithium provides its benefit properties. Lithium medication downregulates GSK-3beta, the main inhibitor of the WNT/β-catenin pathway. The stimulation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway. Future prospective clinical trials could focus on lithium and its different and multiple interactions in PD.

β-catenin promotes MTX resistance of leukemia cells by down-regulating FPGS expression via NF-κB

Background

Aberrant activation of β-catenin has been shown to play important roles in the chemoresistance of acute lymphoblastic leukemia (ALL), but the involvement and mechanism of β-catenin in methotrexate (MTX) resistance is poorly understood. In the present study, we demonstrate a critical role of β-catenin-NF-κB-FPGS pathway in MTX resistance in the human T-lineage ALL cell lines.

Methods

Lentivirus sh-β-catenin was used to silence the expression of β-catenin. Flow cytometry was performed to detect apoptosis after MTX treatment. Western blot, real-time PCR, Co-immunoprecipitation (Co-IP), Chromatin immunoprecipitation (ChIP), Re-ChIP, and Luciferase assay were utilized to investigate the relationship among β-catenin, nuclear factor (NF)-κB, and folypoly-γ-glutamate synthetase (FPGS).

Results

Depletion of β-catenin significantly increased the cytotoxicity of MTX. At the molecular level, knockdown of β-catenin caused the increase of the protein level of FPGS and NF-κB p65. Furthermore, β-catenin complexed with NF-κB p65 and directly bound to the FPGS promoter to regulate its expression. In addition, β-catenin repression prolonged the protein turnover of FPGS.

Conclusions

Taken together, our results demonstrate that β-catenin may contribute to MTX resistance in leukemia cells via the β-catenin-NF-κB-FPGS pathway, posing β-catenin as a potential target for combination treatments during ALL therapy.

Endothelial cell-glucocorticoid receptor interactions and regulation of Wnt signaling

Vascular inflammation is present in many cardiovascular diseases, and exogenous glucocorticoids have traditionally been used as a therapy to suppress inflammation. However, recent data have shown that endogenous glucocorticoids, acting through the endothelial glucocorticoid receptor, act as negative regulators of inflammation. Here, we performed ChIP for the glucocorticoid receptor, followed by next-generation sequencing in mouse endothelial cells to investigate how the endothelial glucocorticoid receptor regulates vascular inflammation. We identified a role of the Wnt signaling pathway in this setting and show that loss of the endothelial glucocorticoid receptor results in upregulation of Wnt signaling both in vitro and in vivo using our validated mouse model. Furthermore, we demonstrate glucocorticoid receptor regulation of a key gene in the Wnt pathway, Frzb, via a glucocorticoid response element gleaned from our genomic data. These results suggest a role for endothelial Wnt signaling modulation in states of vascular inflammation.

Growth inhibition and apoptosis in colorectal cancer cells induced by Vitamin D-Nanoemulsion (NVD): involvement of Wnt/β-catenin and other signal transduction pathways

BACKGROUND

More than the two decades, the question of whether vitamin D has a role in cancer frequency, development, and death has been premeditated in detail. Colorectal, breast, and prostate cancers have been a scrupulous spot of center, altogether, these three malignancies report for approximately 35% of cancer cases and 20% of cancer demises in the United States, and as such are a chief public health apprehension. The aim was to evaluate antitumor activity of Vitamin D-Nanoemulsion (NVD) in colorectal cancer cell lines and HCT116 xenograft model in a comprehensive approach.

METHODS

Two human colorectal cancer cell lines HCT116 and HT29 (gained from College of Pharmacy, King Saud University, KSA were grown. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide protocol were performed to show the impact of NVD and β-catenin inhibitor (FH535) on the viability of HCT116 and HT29 cell lines. Apoptosis/cell cycle assay was performed. Analysis was done with a FACScan (Becton-Dickinson, NJ). About 10,000 cells per sample were harvested and Histograms of DNA were analyzed with ModiFitLT software (verity Software House, ME, USA). Western blotting and RT-PCR were performed for protein and gene expression respectively in in vitro and in vivo.

RESULTS

We found that NVD induced cytotoxicity in colorectal cells in a dose-dependent manner and time dependent approach. Further, our data validated that NVD administration of human colorectal cancer HCT116 and HT29 cells resulted in cell growth arrest, alteration in molecules regulating cell cycle operative in the G2 phase of the cell cycle and apoptosis in a dose dependent approach. Further our results concluded that NVD administration decreases expression of β-catenin gene, AKT gene and Survivin gene and protein expression in in vitro and in vivo.

CONCLUSION

Our findings suggest that targeting β-catenin gene may encourage the alterations of cell cycle and cell cycle regulators. Wnt/β-catenin signaling pathway possibly takes part in the genesis and progression of colorectal cancer cells through regulating cell cycle and the expression of cell cycle regulators.

Taxifolin, a natural flavonoid interacts with cell cycle regulators causes cell cycle arrest and causes tumor regression by activating Wnt/ β -catenin signaling pathway

Background

New approaches for the prevention of colon cancer perseveres an essential necessity. Though, resistance to existing chemo-preventive drugs is moderately predominant in colon carcinogenesis. Taxifolin (dihydroquercetin) is a flavononol, have shown virile biological activities against few cancers. The current study was designed to investigate and equate antitumor activity of Taxifolin (TAX) in colorectal cancer cell lines and in HCT116 xenograft model in a comprehensive approach.

Methods

Two human colorectal cancer cell lines HCT116 and HT29, were used. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide (MMT) protocol was performed to elucidate the impact of TAX and β- catenin inhibitor (FH535) on the viability of HCT116 and HT29 cell lines. Apoptosis /cell cycle assay was performed. Data interpretation was done with a FACScan (Becton Dickinson, NJ). About 1 × 10⁴ cells per sample were harvested. Histograms of DNA were analyzed with ModiFitLT software (verity Software House, ME, USA). Western blotting and RT-PCR were performed for protein and gene expression respectively in in vitro and in vivo.

Results

We found that TAX induced cytotoxicity in colorectal cells in a dose-dependent manner and time dependent approach. Further, our data validated that administration of TAX to human colorectal cancer HCT116 and HT29 cells resulted in cell growth arrest, variation in molecules controlling cell cycle operative in the G2 phase of the cell cycle and apoptosis in a concentration dependent approach. Further our results concluded that TAX administration decreases expression of β-catenin gene, AKT gene and Survivin gene and protein expression in in vitro and in vivo.

Conclusion

Our findings proposed that targeting β-catenin gene may encourage the alterations of cell cycle and cell cycle regulators. Wnt/β-catenin signaling pathway possibly takes part in the genesis and progression of colorectal cancer cells through regulating cell cycle and the expression of cell cycle regulators.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4959-4) contains supplementary material, which is available to authorized users.

Crosstalk between Wnt/β-Catenin and NF-κB Signaling Pathway during Inflammation

Besides its important role in embryonic development and homeostatic self-renewal in adult tissues, Wnt/β-catenin signaling exerts both anti-inflammatory and proinflammatory functions. This is, at least partially, due to either repressing or enhancing the NF-κB pathway. Similarly, the NF-κB pathway either positively or negatively regulates Wnt/β-catenin signaling. Different components of the two pathways are involved in this crosstalk, forming a complex regulatory network. This review summarizes our current understanding of the molecular mechanisms underlying the cross-regulation between the two pathways and discusses their involvement in inflammation and inflammation-associated diseases such as cancer.

Resolution of inflammation: a new therapeutic frontier

Dysregulated inflammation is a central pathological process in diverse disease states. Traditionally, therapeutic approaches have sought to modulate the pro- or anti-inflammatory limbs of inflammation, with mixed success. However, insight into the pathways by which inflammation is resolved has highlighted novel opportunities to pharmacologically manipulate these processes - a strategy that might represent a complementary (and perhaps even superior) therapeutic approach. This Review discusses the state of the art in the biology of resolution of inflammation, highlighting the opportunities and challenges for translational research in this field.

A Cytosolic Multiprotein Complex Containing p85α Is Required for β-Catenin Activation in Colitis and Colitis-associated Cancer

Wnt/β-catenin signaling is required for crypt structure maintenance. We previously observed nuclear accumulation of Ser-552 phosphorylated β-catenin (pβ-Cat(Ser-552)) in intestinal epithelial cells (IEC) during colitis and colitis-associated cancer. Data here delineate a novel multiprotein cytosolic complex (MCC) involved in β-catenin signaling in the intestine. The MCC contains p85α, the class IA subunit of PI3K, along with β-catenin, 14-3-3ζ, Akt, and p110α. MCC levels in IEC increase in colitis and colitis-associated cancer patients. IEC-specific p85α-deficient (p85(ΔIEC)) mice develop more severe dextran sodium sulfate colitis due to delayed ulcer healing and reduced epithelial β-catenin activation. In colonic IEC, p85α deficiency did not alter PI3K signaling. In vitro shRNA depletion of individual complex members disrupts the MCC and reduces β-catenin signaling. Despite worse colitis, p85(ΔIEC) mice have reduced tumor burden after azoxymethane/dextran sodium sulfate treatment. Together the data indicate that the β-catenin MCC is needed for mucosal repair and carcinogenesis. This novel MCC may be an attractive therapeutic target in preventing cancer in colitis patients.