Danggui Shaoyao San Alleviates Early Cognitive Impairment in Alzheimer's Disease Mice Through IRS1/GSK3ß/Wnt3a-ß-Catenin Pathway.

INTRODUCTION: Alzheimer's disease (AD) is a neurodegenerative disease characterized by Amyloid plaques and neurofibrillary tangles. We explored the potential mechanism by which Danggui Shaoyao San (DSS) modulates central glucose metabolism via the insulin receptor substrate 1 (IRS1)/glycogen synthase kinase-3ß (GSK3ß)/Wnt3a-ß-catenin pathway, thereby exerting protective effects on cognitive functions. METHODS: In vitro, HT22 cells were induced with streptozotocin (STZ) to investigate the impact of GSK3ß on pathway transduction. The active components in the DSS stock solution were validated using mass spectrometry. Subsequently, an AD model in C57BL/6J mice was established through STZ injection into both ventricles. The success of the model was validated behaviorally and pathologically. The Morris Water Maze (MWM) test, immunohistochemistry, Western blotting, quantitative reverse transcription-PCR, and 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) were employed to evaluate the influence of DSS on memory and pathological changes in AD. RESULTS: The DSS stock solution, rich in active components, ameliorated the memory deficits in AD mice in the MWM. In vitro, GSK3ß exhibited regulatory control over Wnt and ß-catenin, with GSK3ß inhibition mitigating ß-amyloid and tau redundancies at protein and gene levels, facilitating signal transduction. In vivo, DSS impacted key targets in the IRS1/GSK3ß/Wnt3a-ß-catenin pathway, mitigated senile plaques resulting from amyloid ß (Aß) deposition and neurofiber tangles induced by tau hyperphosphorylation, and alleviated the decline in central glucose metabolism observed in FDG-PET. CONCLUSIONS: Our findings suggest that DSS potentially confers cognitive protection by alleviating central hypoglycemia through the IRS1/GSK3ß/Wnt3a-ß-catenin pathway. This may serve as a promising therapeutic avenue for AD.

O-GlcNAcylation mediates Wnt-stimulated bone formation by rewiring aerobic glycolysis.

Wnt signaling is an important target for anabolic therapies in osteoporosis. A sclerostin-neutralizing antibody (Scl-Ab), that blocks the Wnt signaling inhibitor (sclerostin), has been shown to promote bone mass in animal models and clinical studies. However, the cellular mechanisms by which Wnt signaling promotes osteogenesis remain to be further investigated. O-GlcNAcylation, a dynamic post-translational modification of proteins, controls multiple critical biological processes including transcription, translation, and cell fate determination. Here, we report that Wnt3a either induces O-GlcNAcylation rapidly via the Ca2+-PKA-Gfat1 axis, or increases it in a Wnt-ß-catenin-dependent manner following prolonged stimulation. Importantly, we find O-GlcNAcylation indispensable for osteoblastogenesis both in vivo and in vitro. Genetic ablation of O-GlcNAcylation in the osteoblast-lineage diminishes bone formation and delays bone fracture healing in response to Wnt stimulation in vivo. Mechanistically, Wnt3a induces O-GlcNAcylation at Serine 174 of PDK1 to stabilize the protein, resulting in increased glycolysis and osteogenesis. These findings highlight O-GlcNAcylation as an important mechanism regulating Wnt-induced glucose metabolism and bone anabolism.

Wnt5a Promotes Axon Elongation in Coordination with the Wnt-Planar Cell Polarity Pathway.

The establishment of neuronal polarity, involving axon specification and outgrowth, is critical to achieve the proper morphology of neurons, which is important for neuronal connectivity and cognitive functions. Extracellular factors, such as Wnts, modulate diverse aspects of neuronal morphology. In particular, non-canonical Wnt5a exhibits differential effects on neurite outgrowth depending upon the context. Thus, the role of Wnt5a in axon outgrowth and neuronal polarization is not completely understood. In this study, we demonstrate that Wnt5a, but not Wnt3a, promotes axon outgrowth in dissociated mouse embryonic cortical neurons and does so in coordination with the core PCP components, Prickle and Vangl. Unexpectedly, exogenous Wnt5a-induced axon outgrowth was dependent on endogenous, neuronal Wnts, as the chemical inhibition of Porcupine using the IWP2- and siRNA-mediated knockdown of either Porcupine or Wntless inhibited Wnt5a-induced elongation. Importantly, delayed treatment with IWP2 did not block Wnt5a-induced elongation, suggesting that endogenous Wnts and Wnt5a act during specific timeframes of neuronal polarization. Wnt5a in fibroblast-conditioned media can associate with small extracellular vesicles (sEVs), and we also show that these Wnt5a-containing sEVs are primarily responsible for inducing axon elongation.

Positive cooperativity in synergistic activation of Wnt proteins.

BACKGROUND: Wnt proteins are crucial for embryonic development, stem cell growth, and tissue regeneration. Wnt signaling pathway is activated when Wnt proteins bind to cell membrane receptors. METHODS AND RESULTS: We employed a luciferase reporter assay in HEK293STF cells to measure Wnt protein-induced signaling. We observed that Wnt3a uniquely promotes the Wnt/ß-catenin pathway through positive cooperativity. Additionally, MFH-ND, a molecular mimic of Wnt ligands, markedly increased Wnt3a-induced signaling in a dose-responsive manner. This suggests that various Wnt ligands can synergistically enhance Wnt pathway activation. CONCLUSIONS: The study suggests the likelihood of various Wnt ligands coexisting in a single signalosome on the cell membrane, providing new insights into the complexities of Wnt signaling mechanisms.

Synergism of Fusobacterium periodonticum and N-nitrosamines promote the formation of EMT subtypes in ESCC by modulating Wnt3a palmitoylation.

N-Nitrosamine disinfection by-products (NAs-DBPs) have been well proven for its role in esophageal carcinogenesis. However, the role of intratumoral microorganisms in esophageal squamous cell carcinoma (ESCC) has not yet been well explored in the context of exposure to NAs-DBPs. Here, the multi-omics integration reveals F. periodonticum (Fp) as "facilitators" is highly enriched in cancer tissues and promotes the epithelial mesenchymal transition (EMT)-like subtype formation of ESCC. We demonstrate that Fp potently drives de novo synthesis of fatty acids, migration, invasion and EMT phenotype through its unique FadAL adhesin. However, N-nitrosomethylbenzylamine upregulates the transcription level of FadAL. Mechanistically, co-immunoprecipitation coupled to mass spectrometry shows that FadAL interacts with FLOT1. Furthermore, FLOT1 activates PI3K-AKT/FASN signaling pathway, leading to triglyceride and palmitic acid (PA) accumulation. Innovatively, the results from the acyl-biotin exchange demonstrate that FadAL-mediated PA accumulation enhances Wnt3A palmitoylation on a conserved cysteine residue, Cys-77, and promotes Wnt3A membrane localization and the translocation of ß-catenin into the nucleus, further activating Wnt3A/ß-catenin axis and inducing EMT phenotype. We therefore propose a "microbiota-cancer cell subpopulation" interaction model in the highly heterogeneous tumor microenvironment. This study unveils a mechanism by which Fp can drive ESCC and identifies FadAL as a potential diagnostic and therapeutic target for ESCC.

Identification of CD19 as a shared biomarker via PPARγ/ß-catenin/Wnt3a pathway linking psoriasis and major depressive disorder.

BACKGROUND: Psoriasis, a chronic inflammatory skin disorder, is frequently linked with metabolic, cardiovascular, and psychological comorbidities. Recent research has highlighted the correlation between psoriasis and major depressive disorder (MDD); however, the underlying mechanism remains unclear. METHODS: Commonly differentially expressed genes (DEGs) in psoriasis and MDD were identified and visualized using data from the GEO database. Subsequently, functional enrichment analysis was conducted using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Genemania. The hub gene was selected through LASSO and Random Forest algorithms, validated in clinical tissues using Student's t-test and Receiver Operating Characteristic curve. To investigate the hub gene's function in disease phenotype, we established imiquimod (IMQ)-induced psoriasiform dermatitis and chronic unpredictable mild stress (CUMS) mouse models. Lentiviral shRNA interference was topically applied in mice, and downstream pathways were validated at the mRNA and protein levels. RESULTS: A total of 395 overlapping DEGs were identified from GSE121212 and GSE54568 datasets, and twenty core genes were extracted. Functional enrichment analysis revealed that the core genes were significantly associated with the Wnt signaling pathway, neurodegeneration, and energy metabolism. CD19 was identified as the hub gene through algorithms, and external validation showed remarkable AUC values of 0.69 and 0.74, respectively. The level of CD19 increased significantly in IMQ-treated and CUMS-treated mice. Suppression of CD19 significantly alleviated the phenotypes of IMQ-induced psoriasiform dermatitis and CUMS-induced depressive-like behaviors by regulating the PPARγ/ß-catenin/Wnt3a pathway. CONCLUSION: CD19 may serve as a common biomarker or therapeutic target of psoriasis and MDD via PPARγ/ß-catenin/Wnt3a pathway.

BRCA Status Dictates Wnt Responsiveness in Epithelial Ovarian Cancer.

The association of BRCA1 and BRCA2 mutations with increased risk for developing epithelial ovarian cancer is well established. However, the observed clinical differences, particularly the improved therapy response and patient survival in BRCA2-mutant patients, are unexplained. Our objective is to identify molecular pathways that are differentially regulated upon the loss of BRCA1 and BRCA2 functions in ovarian cancer. Transcriptomic and pathway analyses comparing BRCA1-mutant, BRCA2-mutant, and homologous recombination wild-type ovarian tumors showed differential regulation of the Wnt/ß-catenin pathway. Using Wnt3A-treated BRCA1/2 wild-type, BRCA1-null, and BRCA2-null mouse ovarian cancer cells, we observed preferential activation of canonical Wnt/ß-catenin signaling in BRCA1/2 wild-type ovarian cancer cells, whereas noncanonical Wnt/ß-catenin signaling was preferentially activated in the BRCA1-null ovarian cancer cells. Interestingly, BRCA2-null mouse ovarian cancer cells demonstrated a unique response to Wnt3A with the preferential upregulation of the Wnt signaling inhibitor Axin2. In addition, decreased phosphorylation and enhanced stability of ß-catenin were observed in BRCA2-null mouse ovarian cancer cells, which correlated with increased inhibitory phosphorylation on GSK3ß. These findings open venues for the translation of these molecular observations into modalities that can impact patient survival. SIGNIFICANCE: We show that BRCA1 and BRCA2 mutation statuses differentially impact the regulation of the Wnt/ß-catenin signaling pathway, a major effector of cancer initiation and progression. Our findings provide a better understanding of molecular mechanisms that promote the known differential clinical profile in these patient populations.

Interaction between the Neuroprotective and Hyperglycemia Mitigation Effects of Walnut-Derived Peptide LVRL via the Wnt3a/ß-Catenin/GSK-3ß Pathway in a Type 2 Diabetes Mellitus Model.

The term type 3 diabetes mellitus (T3DM) has been considered for Alzheimer's disease (AD) due to the common molecular and cellular characteristics found between type 2 diabetes mellitus (T2DM) and cognitive deficits. However, the specific mechanism of T3DM remains elusive, especially the neuroprotective effects of dietary components in hyperglycemic individuals. In this study, a peptide, Leu-Val-Arg-Leu (LVRL), found in walnuts significantly improved memory decline in streptozotocin (STZ)- and high-fat-diet (HFD)-stimulated T2DM mouse models (p < 0.05). The LVRL peptide also mitigated hyperglycemia, enhanced synaptic plasticity, and ameliorated mitochondrial dysfunction, as demonstrated by Morris water maze tests, immunoblotting, immunofluorescence, immunohistochemistry, transmission electron microscopy, and cellular staining. A Wnt3a inhibitor, DKK1, was subsequently used to verify the possible role of the Wnt3a/ß-Catenin/GSK-3ß pathway in glucose-induced insulin resistance in PC12 cells. In vitro LVRL treatment dramatically modulated the protein expression of p-Tau (Ser404), Synapsin-1, and PSD95, elevated the insulin level, increased glucose consumption, and relieved the mitochondrial membrane potential, and MitoSOX (p < 0.05). These data suggested that peptides like LVRL could modulate the relationship between brain insulin and altered cognition status via the Wnt3a/ß-Catenin/GSK-3ß pathway.

Enhanced chondrogenic potential in GelMA-based 3D cartilage model via Wnt3a surface immobilization.

Cartilage tissue engineering aims to develop functional substitutes for treating cartilage defects and osteoarthritis. Traditional two-dimensional (2D) cell culture systems lack the complexity of native cartilage, leading to the development of 3D regenerative cartilage models. In this study, we developed a 3D model using Gelatin Methacryloyl (GelMA)-based hydrogels seeded with Y201 cells, a bone marrow mesenchymal stem cell line. The model investigated chondrogenic differentiation potential in response to Wnt3a stimulation within the GelMA scaffold and validated using known chondrogenic agonists. Y201 cells demonstrated suitability for the model, with increased proteoglycan content and upregulated chondrogenic marker expression under chondrogenic conditions. Wnt3a enhanced cell proliferation, indicating activation of the Wnt/ß-catenin pathway, which plays a role in cartilage development. GelMA hydrogels provided an optimal scaffold, supporting cell viability and proliferation. The 3D model exhibited consistent responses to chondrogenic agonists, with TGF-ß3 enhancing cartilage-specific extracellular matrix (ECM) production and chondrogenic differentiation. The combination of Wnt3a and TGF-ß3 showed synergistic effects, promoting chondrogenic differentiation and ECM production. This study presents a 3D regenerative cartilage model with potential for investigating cartilage biology, disease mechanisms, and drug screening. The model provides insights into complex cartilage regeneration mechanisms and offers a platform for developing therapeutic approaches for cartilage repair and osteoarthritis treatment.

WNT Signaling Cascade Proteins and LRP6 in the Formation of Various Types of Coronary Lesions in Patients With Coronary Artery Disease.

AIM: Assessment of WNT1, WNT3a, and LRP6 concentrations in patients with ischemic heart disease (IHD) and obstructive and non-obstructive coronary artery (CA) disease. MATERIAL AND METHODS: This cross-sectional observational study included 50 IHD patients (verified by coronary angiography, CAG), of which 25 (50%) were men, mean age 64.9±8.1 years; 20 patients had non-obstructive CA disease (stenosis <50%), and 30 patients had hemodynamically significant stenosis. Concentrations of WNT1, WNT3a and LRP6 were measured in all patients. RESULTS: The concentrations of WNT1 and WNT3a proteins were significantly higher in patients with IHD and obstructive CA disease (p < 0.001), while the concentration of LRP6 was higher in the group with non-obstructive CA disease (p = 0.016). Data analysis of the group with obstructive CA disease showed a moderate correlation between WNT1 and LRP6 (ρ=0.374; p=0.042). Correlation analysis of all groups of patients with CA disease revealed a moderate association between the concentrations of WNT1 and uric acid (ρ=0.416; p=0.007). Regression analysis showed that risk factors for the development of IHD, such as increased body mass index, age, smoking, dyslipidemia, and hypertension, did not significantly influence the type of CA disease in IHD patients. According to ROC analysis, the obstructive form of IHD was predicted by a WNT3a concentration higher than 0.155 ng/ml and a LRP6 concentration lower than 12.94 ng/ml. CONCLUSION: IHD patients with non-obstructive CA disease had the greatest increase in LRP6, while patients with obstructive CA disease had significantly higher concentrations of the canonical WNT cascade proteins, WNT1 and WNT3a. According to the ROC analysis, a WNT3a concentration >0.155 ng/ml can serve as a predictor for the presence of hemodynamically significant CA stenosis in IHD patients (sensitivity 96.7%; specificity 70%), whereas a LRP6 concentration >12.94 ng/ml can predict the development of non-obstructive CA disease (sensitivity 76.7%; specificity 65%).

Expression and potential molecular mechanism of TOP2A in metastasis of non-small cell lung cancer.

DNA topoisomerase II alpha (TOP2A) expression, gene alterations, and enzyme activity have been studied in various malignant tumors. Abnormal elevation of TOP2A expression is considered to be related to the development of non-small cell lung cancer (NSCLC). However, its association with tumor metastasis and its mode of action remains unclear. Bioinformatics, real-time quantitative PCR, immunohistochemistry and immunoblotting were used to detect TOP2A expression in NSCLC tissues and cells. Cell migration and invasion assays as well as cytoskeletal staining were performed to analyze the effects of TOP2A on the motility, migration and invasion ability of NSCLC cells. Cell cycle and apoptosis assays were used to verify the effects of TOP2A on apoptosis as well as cycle distribution in NSCLC. TOP2A expression was considerably upregulated in NSCLC and significantly correlated with tumor metastasis and the occurrence of epithelial-mesenchymal transition (EMT) in NSCLC. Additionally, by interacting with the classical ligand Wnt3a, TOP2A may trigger the canonical Wnt signaling pathway in NSCLC. These observations suggest that TOP2A promotes EMT in NSCLC by activating the Wnt/ß-catenin signaling pathway and positively regulates malignant events in NSCLC, in addition to its significant association with tumor metastasis. TOP2A promotes the metastasis of NSCLC by stimulating the canonical Wnt signaling pathway and inducing EMT. This study further elucidates the mechanism of action of TOP2A, suggesting that it might be a potential therapeutic target for anti-metastatic therapy.

Splice variants of CK1α and CK1α-like: Comparative analysis of subcellular localization, kinase activity, and function in the Wnt signaling pathway.

Members of the casein kinase 1 (CK1) family are important regulators of multiple signaling pathways. CK1α is a well-known negative regulator of the Wnt/ß-catenin pathway, which promotes the degradation of ß-catenin via its phosphorylation of Ser45. In contrast, the closest paralog of CK1α, CK1α-like, is a poorly characterized kinase of unknown function. In this study, we show that the deletion of CK1α, but not CK1α-like, resulted in a strong activation of the Wnt/ß-catenin pathway. Wnt-3a treatment further enhanced the activation, which suggests there are at least two modes, a CK1α-dependent and Wnt-dependent, of ß-catenin regulation. Rescue experiments showed that only two out of ten naturally occurring splice CK1α/α-like variants were able to rescue the augmented Wnt/ß-catenin signaling caused by CK1α deficiency in cells. Importantly, the ability to phosphorylate ß-catenin on Ser45 in the in vitro kinase assay was required but not sufficient for such rescue. Our compound CK1α and GSK3α/ß KO models suggest that the additional nonredundant function of CK1α in the Wnt pathway beyond Ser45-ß-catenin phosphorylation includes Axin phosphorylation. Finally, we established NanoBRET assays for the three most common CK1α splice variants as well as CK1α-like. Target engagement data revealed comparable potency of known CK1α inhibitors for all CK1α variants but not for CK1α-like. In summary, our work brings important novel insights into the biology of CK1α, including evidence for the lack of redundancy with other CK1 kinases in the negative regulation of the Wnt/ß-catenin pathway at the level of ß-catenin and Axin.

A small molecule compound 759 inhibits the wnt/beta-catenin signaling pathway via increasing the Axin protein stability.

Wnt/ß-catenin signaling plays important role in cancers. Compound 759 is one of the compounds previously screened to identify inhibitors of the Wnt/ß-catenin pathway in A549 cells [Lee et al. in Bioorg Med Chem Lett 20:5900-5904, 2010]. However, the mechanism by which Compound 759 induces the inhibition of the Wnt/ß-catenin pathway remains unknown. In our study, we employed various assays to comprehensively evaluate the effects of Compound 759 on lung cancer cells. Our results demonstrated that Compound 759 significantly suppressed cell proliferation and Wnt3a-induced Topflash activity and arrested the cell cycle at the G1 stage. Changes in Wnt/ß-catenin signaling-related protein expression, gene activity, and protein stability including Axin, and p21, were achieved through western blot and qRT-PCR analysis. Compound 759 treatment upregulated the mRNA level of p21 and increased Axin protein levels without altering the mRNA expression in A549 cells. Co-treatment of Wnt3a and varying doses of Compound 759 dose-dependently increased the amounts of Axin1 in the cytosol and inhibited ß-catenin translocation into the nucleus. Moreover, Compound 759 reduced tumor size and weight in the A549 cell-induced tumor growth in the in vivo tumor xenograft mouse model. Our findings indicate that Compound 759 exhibits potential anti-cancer activity by inhibiting the Wnt/ß-catenin signaling pathway through the increase of Axin1 protein stability.

rESWT promoted angiogenesis via Bach1/Wnt/ß-catenin signaling pathway.

Previous reports have established that rESWT fosters angiogenesis, yet the mechanism by which rESWT promotes cerebral angiogenesis remains elusive. rESWT stimulated HUVECs proliferation as evidenced by the CCK-8 test, with an optimal dosage of 2.0 Bar, 200 impulses, and 2 Hz. The tube formation assay of HUVECs revealed that tube formation peaked at 36 h post-rESWT treatment, concurrent with the lowest expression level of Bach1, as detected by both Western blot and immunofluorescence. The expression level of Wnt3a, ß-catenin, and VEGF also peaked at 36 h. A Bach1 overexpression plasmid was transfected into HUVECs, resulting in a decreased expression level of Wnt3a, ß-catenin, and VEGF. Upon treatment with rESWT, the down-regulation of Wnt3a, ß-catenin, and VEGF expression in the transfected cells was reversed. The Wnt/ß-catenin inhibitor DKK-1 was utilized to suppress Wnt3a and ß-catenin expression, which led to a concurrent decrease in VEGF expression. However, rESWT treatment could restore the expression of these three proteins, even in the presence of DKK-1. Moreover, in the established OGD model, it was observed that rESWT could inhibit the overexpression of Bach1 and enhance VEGF and VEGFR-2 expression under the OGD environment.

Understanding the molecular mechanism of regeneration through apoptosis-induced compensatory proliferation studies - updates and future aspects.

AICP is a crucial process that maintaining tissue homeostasis and regeneration. In the past, cell death was perceived merely as a means to discard cells without functional consequences. However, during regeneration, effector caspases orchestrate apoptosis, releasing signals that activate stem cells, thereby compensating for tissue loss across various animal models. Despite significant progress, the activation of Wnt3a by caspase-3 remains a focal point of research gaps in AICP mechanisms, spanning from lower to higher regenerative animals. This inquiry into the molecular intricacies of caspase-3-induced Wnt3a activation contributes to a deeper understanding of the links between regeneration and cancer mechanisms. Our report provides current updates on AICP pathways, delineating research gaps and highlighting the potential for future investigations aimed at enhancing our comprehension of this intricate process.

DKK1 Activates the PI3K/AKT Pathway via CKAP4 to Balance the Inhibitory Effect on Wnt/ß-Catenin Signaling and Regulates Wnt3a-Induced MSC Migration.

Wnt/ß-catenin signaling plays a crucial role in the migration of mesenchymal stem cells (MSCs). However, our study has revealed an intriguing phenomenon where Dickkopf-1 (DKK1), an inhibitor of Wnt/ß-catenin signaling, promotes MSC migration at certain concentrations ranging from 25 to 100 ng/mL while inhibiting Wnt3a-induced MSC migration at a higher concentration (400 ng/mL). Interestingly, DKK1 consistently inhibited Wnt3a-induced phosphorylation of LRP6 at all concentrations. We further identified cytoskeleton-associated protein 4 (CKAP4), another DKK1 receptor, to be localized on the cell membrane of MSCs. Overexpressing the CRD2 deletion mutant of DKK1 (ΔCRD2), which selectively binds to CKAP4, promoted the accumulation of active ß-catenin (ABC), the phosphorylation of AKT (Ser473) and the migration of MSCs, suggesting that DKK1 may activate Wnt/ß-catenin signaling via the CKAP4/PI3K/AKT cascade. We also investigated the effect of the CKAP4 intracellular domain mutant (CKAP4-P/A) that failed to activate the PI3K/AKT pathway and found that CKAP4-P/A suppressed DKK1 (100 ng/mL)-induced AKT activation, ABC accumulation, and MSC migration. Moreover, CKAP4-P/A significantly weakened the inhibitory effects of DKK1 (400 ng/mL) on Wnt3a-induced MSC migration and Wnt/ß-catenin signaling. Based on these findings, we propose that DKK1 may activate the PI3K/AKT pathway via CKAP4 to balance the inhibitory effect on Wnt/ß-catenin signaling and thus regulate Wnt3a-induced migration of MSCs. Our study reveals a previously unrecognized role of DKK1 in regulating MSC migration, highlighting the importance of CKAP4 and PI3K/AKT pathways in this process.

Wnt3a/GSK3ß/ß-catenin Signalling Modulates Doxorubicin-associated Memory Deficits in Breast Cancer.

BACKGROUND: Chemobrain is widespread in breast cancer patients receiving chemotherapy. However, the exact mechanism, especially the associated signalling pathway, is not currently clear. This study was to evaluate the behavioural changes in breast cancer mice after chemotherapy and to further explore the role of Wnt3a/glycogen synthase kinase (GSK3ß)/ß-catenin signalling in chemobrain. METHODS: MMTV-PyMT(+) breast cancer mice were injected intraperitoneally with doxorubicin (4 mg/kg) once a week for three weeks to establish a chemobrain model. The Morris water maze (MWM) and novel object recognition (NOR) tests were performed to assess the learning and memory ability. Electron microscopy was used to observe the structural changes in the hippocampal CA1 region. The brain tissue of breast cancer mice after chemotherapy was taken out for mRNA-seq detection. Then, the expression levels and phosphorylation of key proteins in the Wnt3a/GSK3 ß/ß-catenin signalling pathway were evaluated through Western blotting (WB) and immunofluorescence. RESULTS: Doxorubicin-induced spatial and short-term memory impairment was observed in breast cancer mice, and obvious neuronal damage could be seen in the hippocampal CA1 region. Immunofluorescence staining for GSK3ß was increased. Wnt signalling pathway is highly enriched from mRNA-seq analysis, with GSK3ß genes at important nodes. The relative protein levels of p-PI3K, p-AKT, p-GSK3 ß, Wnt3a and TCF-1 were decreased significantly, while the p-ß-catenin level was increased. After injection of the GSK3ß inhibitor sb216763 (1 ng/0.5 µl/side), hippocampal neuronal injury was alleviated to some extent, and the changes in the expression of proteins upstream and downstream of this signalling pathway were reversed. CONCLUSION: Wnt3a/GSK3 ß/ß-catenin signalling is likely involved in doxorubicin-induced memory impairment. This result provides basic evidence for the further study of chemobrain in breast cancer.

Wnt-3a improves functional recovery after spinal cord injury by regulating the inflammatory and apoptotic response in rats via wnt/ß-catenin signaling pathway.

The specific molecular mechanism of neuroprotective effects of wnt-3a on spinal cord injury (SCI) has not been elucidated. In our study, we evaluated the recovery of motor function after SCI by BBB, observed neuronal apoptosis by western blot and TUNEL, observed the changes of neuronal inflammation by western blot and immunofluorescence staining, and observed the changes of motoneurons and spinal cord area in the anterior horn of the spinal cord via Nissl and HE staining. We found that wnt-3a could significantly promote the recovery of motor function, reduce the loss of motor neurons in the anterior horn of the spinal cord, promote the recovery of injured spinal cord tissue, inhibit neuronal apoptosis and inflammatory response, and ultimately promote neuronal function after SCI. However, when XAV939 inhibits the wnt/ß-catenin signaling pathway, the neuroprotective effects of wnt-3a are also significantly inhibited. The above results together indicated that wnt-3a exerts its neuroprotective effect on after SCI via activating the wnt/ß-catenin signaling pathway.

The selenoprotein P-LRP5/6-WNT3A complex promotes tumorigenesis in sporadic colorectal cancer.

Some studies suggest that the trace element selenium protects against colorectal cancer (CRC). However, the contribution of selenoprotein P (SELENOP), a unique selenocysteine-containing protein, to sporadic colorectal carcinogenesis challenges this paradigm. SELENOP is predominately secreted by the liver but is also expressed in various cells of the small intestine and colon in mice and humans. In this issue of the JCI, Pilat et al. demonstrate that increased SELENOP expression promoted the progression of conventional adenomas to carcinoma. SELENOP functioned as a modulator of canonical WNT signaling activity through interactions with WNT3A and its coreceptor LDL receptor-related protein 5/6 (LRP5/6). Secreted SELENOP formed a concentration gradient along the gut crypt axis, which might amplify WNT signaling activity by binding to LRPL5/6. The mechanism for WNT control via SELENOP may affect colorectal tumorigenesis and provide therapeutic targets for CRC.

hsa­miR­216a­3p regulates cell proliferation in oral cancer via the Wnt3a/ß­catenin pathway.

Oral cancer is one of the leading causes of death worldwide, with a reported 5­year survival rate of ~50% after treatment. The treatment measures for oral cancer are very expensive and affordability is low. Thus, it is necessary to develop more effective therapies to treat oral cancer. A number of studies have found that miRNAs are invasive biomarkers and have therapeutic potential in a variety of cancers. The present study included 30 oral patients and 30 healthy controls. Clinicopathological characteristic and miR­216a­3p/ß­catenin expression level of 30 oral cancer patients were analyzed. In addition, two oral cancer cell lines (HSC­6 and CAL­27) were used for mechanism­of­action study. The expression level of miR­216a­3p was higher in oral cancer patients compared with healthy controls and positively associated with tumor stage. Inhibition of miR­216a­3p potently suppressed cell viability and induced apoptosis of oral cancer cells. It was found that effects of miR­216a­3p on oral cancer were through Wnt3a signaling. It was also found that the expression level of ß­catenin was higher in oral cancer patients compared with healthy controls and positively associated with tumor stage; the effects of miR­216a­3p on oral cancer were through ß­catenin. In conclusion, miR­216a­3p and the Wnt­ß­catenin signaling pathway may be interesting candidates to develop effective therapies for oral cancers.