Non-canonical Wnt Signaling Pathway Research Articles

Burden of rare deleterious variants in WNT signaling genes among 511 myelomeningocele patients.

Genes in the noncanonical WNT signaling pathway controlling planar cell polarity have been linked to the neural tube defect myelomeningocele. We hypothesized that some genes in the WNT signaling network have a higher mutational burden in myelomeningocele subjects than in reference subjects in gnomAD. Exome sequencing data from 511 myelomeningocele subjects was obtained in-house and data from 29,940 ethnically matched subjects was provided by version 2 of the publicly available Genome Aggregation Database. To compare mutational burden, we collapsed rare deleterious variants across each of 523 human WNT signaling genes in case and reference populations. Ten WNT signaling genes were disrupted with a higher mutational burden among Mexican American myelomeningocele subjects compared to reference subjects (Fishers exact test, P ≤ 0.05) and seven different genes were disrupted among individuals of European ancestry compared to reference subjects. Gene ontology enrichment analyses indicate that genes disrupted only in the Mexican American population play a role in planar cell polarity whereas genes identified in both populations are important for the regulation of canonical WNT signaling. In summary, evidence for WNT signaling genes that may contribute to myelomeningocele in humans is presented and discussed.

Beta-catenin non-canonical pathway: A potential target for inflammatory and hyperproliferative state via expression of transglutaminase 2 in psoriatic skin keratinocyte.

Psoriasis is a chronic, local as well as a systemic, inflammatory skin condition. Psoriasis influences the quality of life up to 3.8% of the population and occurs often between 15 and 30 years of age. Specific causes are linked to psoriasis, including the interleukin IL-23/IL-17 Axis, human antigen leucocyte (HLA), and tumor necrosis factor-α (TNF-α). Secukinumab is a monoclonal antibody that specifically binds and neutralizes IL-17A required in the treatment of Psoriasis. The signaling pathways of Wnt govern multiple functions of cell-like fate specification, proliferation, polarity, migration, differentiation with their signaling controlled rigorously, given that dysregulation caused by various stimuli, can lead to alterations in cell proliferation, apoptosis, and human inflammatory disease. Current data has supported non-canonical Wnt signaling pathways in psoriasis development, particularly Wnt5a activated signaling cascades. These interconnected factors are significant in interactions between immune cells, keratinocytes, and inflammatory factors due to a higher degree of transglutaminase 2, mediated by activation of the keratinocyte hyperproliferation of the psoriatic patient's epidermis. This study discusses the pathology of Wnt5a signaling and its involvement in the epidermal inflammatory effects of psoriasis with other related pathways.

Transition between canonical to non-canonical Wnt signaling during interactions between mesenchymal stem cells and osteosarcomas

Background: Wnt signaling pathways are taking a part in regulation of cell fate decisions in normal and cancerous cells. In some cancer types, a transition from canonical to non-canonical Wnt signaling pathways was identified, a phenomenon, that in return led to increase proliferation, invasiveness and metastasis. Methods: In the current in vitro study we investigated the influence of MSCs, co-cultured in direct and indirect contact with OS cells, on the role of Wnt signaling pathways and tumor aggressiveness. Sub-populations were separated using Boyden chambers. Gene expression profiles were determined by qPCR. Results: The results revealed that interactions with MSCs increased migration and invasion capacities along with OS proliferation. Moreover, canonical Wnt signaling activity was low in OS, and co-culture with MSC. However, MSCs did not trigger a switch between the canonical to the no-canonical Wnt pathways. In addition, a more aggressive OS sub-population tend to undergo a transition towards the non-canonical pathway. Moreover, this aggressive subtype presented cancer stem-cells like characteristic. Conclusions: We submit that the progression in OS aggressiveness is attributed to a transition in Wnt signaling from canonical to non-canonical pathways, although MSCs are likely to take a part during the tumor progression, in the case of OS, they did not affect the Wnt switch. These complex tumor promoting interactions may be found in the natural and tumorigenic bone microenvironment. A better understanding of the molecular signaling mechanisms involved in the tumor development and metastasis may contribute to development of new cancer therapies.

Differential expression of microRNAs in the human fetal left and right cerebral cortex.

Human brain is anatomically and functionally asymmetric. How brain asymmetry is initiated and established during fetal development is poorly understood. Accumulating evidence has shown that microRNAs (miRNAs) play crucial roles in brain development and function. In this study, we investigate miRNA expression profiles in left and right hemispheres of human fetal brains at 12weeks post conception (PC), and identify 42 miRNAs showing differential expression between two hemispheres using Affymetrix microarray analyses. Target genes for left- and right-biased miRNAs are largely involved in developmental and functional regulations in the cortex such as axon guidance, GABAergic synapse and dopaminergic synapse pathways. Moreover, we find that predicted targets associated with canonical and non-canonical WNT signaling pathway show variations and differential expression between two hemispheres in response to left- and right-biased miRNAs. Our results highlight a potential role of miRNAs in regulating asymmetric development of human fetal brains.

Abstract 2757: Analysis of stromal myofibroblasts identifies secreted proteins that promote pancreatic ductal adenocarcinoma

Abstract Pancreatic ductal adenocarcinoma (PDAC) is one of the most incurable types of cancer. Cancer that develops in the acinar cells of the pancreas is typically not diagnosed until later stages, such as stage 3 or 4. As such, this form of cancer is particularly lethal with only 9% of patients reaching 5-year survival. PDAC is known to have a particularly dense extracellular matrix composed of fibroblasts, which have been previously shown to play an important role in promoting resistance to drug therapy. Characterization of the stromal networks involved in PDAC tumor development as well as protein markers of fibroblast subpopulations within the tumor stroma are critical to developing new fibroblast-targeted therapeutic approaches as well as understanding key signaling molecules that ultimately promote tumor progression and drug resistance. Single-cell RNA sequencing (scRNAseq) was utilized to analyze cancer-associated fibroblasts (CAFs) from KPC mouse-derived, MT3 subcutaneous murine allografts along with two fibroblast lines derived from human PDAC tumors: CRC-811 and IA-1340. Single cell gene expression profiling and subsequent analysis of MT3-derived CAFs resulted in the identification of three CAF subpopulations including a myofibroblast subpopulation that expressed high levels of smooth muscle actin (Acta2), which was also observed in both human samples. Fibroblast subpopulations enriched in Acta2 expression, expressed high levels of Wnt5a along with several other secreted factors including Tgfb1, Tgfb2 and Ctgf. Wnt5a is a secreted protein that activates non-canonical Wnt signaling pathways and is known to regulate normal developmental processes, including proliferation, differentiation, migration, adhesion and polarity. However Wnt5a is not natively expressed in MT3 cancer cells derived from syngeneic tumors, but potentially in the stroma. We hypothesize it is exclusively derived from fibroblasts. Previously it has been shown that Wnt5a inhibition suppressed gastric cancer metastasis, therefore further validation of the role of myofibroblast-derived Wnt5a on PDAC disease progression is warranted. This study received funding by LDRD 19-SI-003. This work was conducted under the auspices of the USDOE by LLNL (DE-AC52-07NA27344). IM Release Number: LLNL-ABS-798442. Citation Format: Kelly A. Martin, Aimy Sebastian, Nicholas R. Hum, Stephen Byers, Elizabeth K. Wheeler, Matthew A. Coleman, Gabriela G. Loots. Analysis of stromal myofibroblasts identifies secreted proteins that promote pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2757.

The structural biology of canonical Wnt signalling.

The Wnt signalling pathways are of great importance in embryonic development and oncogenesis. Canonical and non-canonical Wnt signalling pathways are known, with the canonical (or β-catenin dependent) pathway being perhaps the best studied of these. While structural knowledge of proteins and interactions involved in canonical Wnt signalling has accumulated over the past 20 years, the pace of discovery has increased in recent years, with the structures of several key proteins and assemblies in the pathway being released. In this review, we provide a brief overview of canonical Wnt signalling, followed by a comprehensive overview of currently available X-ray, NMR and cryoEM data elaborating the structures of proteins and interactions involved in canonical Wnt signalling. While the volume of structures available is considerable, numerous gaps in knowledge remain, particularly a comprehensive understanding of the assembly of large multiprotein complexes mediating key aspects of pathway, as well as understanding the structure and activation of membrane receptors in the pathway. Nonetheless, the presently available data affords considerable opportunities for structure-based drug design efforts targeting canonical Wnt signalling.

Combination of Salinomycin and AZD3463 Reveals Synergistic Effect on Reducing the Viability of T98G Glioblastoma Cells.

Salinomycin, an ionophore antibiotic, is known to be an effective agent in reducing the viability of Glioblastoma (GBM) cells. The combination of salinomycin with other chemotherapeutic drugs would help to overcome the drug resistance of GBM cells. This study aims to test the combinatorial effect of salinomycin and AZD3463 in T98G GBM cells. The cytotoxic effects of drugs on T98G GBM cells were determined by using WST-8 assay. Flow cytometry was used to identify apoptosis and cell cycle profiles after treatments. Real-time PCR was used to portray mRNA expression profiles of genes in the Wnt-signaling pathway after treatments. IC50 concentrations of AZD3463 and salinomycin were 529nM and 7.3μM for 48h, respectively. The combination concentrations of AZD3463 and salinomycin were 3.3μM and 333nM, respectively. The combination treatment showed a synergistic effect on reducing the viability of GBM cells. AZD3463, salinomycin, and their combination induced apoptosis in 1.2, 1.4, and 3.2 folds, respectively. AZD3463 and the combination treatment induced the cell cycle arrest at the G1 phase. Salinomycin and AZD3463 treatments, either alone or in combination, resulted in the downregulation or upregulation of mRNA expression levels of genes in the Wntsignaling pathway. Salinomycin, AZD3463, and their combination may inhibit proliferation and induce apoptosis in GBM cells due to a decrease in expression levels of genes acting in both the canonical and non-canonical Wnt signaling pathways. The Wnt signaling pathway may be involved in salinomycin-AZD3463 drug interaction.

Tanshinone IIA promotes cardiac differentiation and improves cell motility by modulating the Wnt/β‑catenin signaling pathway.

Although the cardiovascular pharmacological actions of Tanshinone IIA (TanIIA) have been extensively studied, research on its roles in cardiac regeneration is still insufficient. The present study employed the cardiac myoblast cell line H9c2 to evaluate the possible roles of TanIIA in cardiac regeneration. It was found that certain concentration of TanIIA inhibited cell proliferation by suppressing the expression of proteins related to the cell cycle [cyclin dependent kinase (CDK)4, CDK6 and cyclin D1] and proliferation [c-Myc, octamer-binding transcription factor 4 (Oct4) and proliferating cell nuclear antigen (PCNA)] without inducing apoptosis. In this process, the expression of cardiac troponin in the treated cells was significantly increased and the migration of the treated cells toward the wound area was significantly enhanced. Meanwhile, TanIIA inhibited the canonical signaling pathway through increasing the expression of glycogen synthase kinase 3β (GSK-3β) and adenomatous polyposis coli (APC) and increased the expression of Wnt11 and Wnt5a in the noncanonical Wnt signaling pathway. Following β-catenin agonist WAY-262611 intervention, the effect of TanIIA on the promotion of cardiac differentiation and improved cell migration was significantly reduced. In conclusion, it was hypothesized that TanIIA could promote cardiac differentiation and improve cell motility by modulating the Wnt/β-catenin signaling pathway. These results suggest that TanIIA may play beneficial roles in myocardial regeneration following stem cell transplantation.

159 Downregulation of serum exosome miR-1305 contribute to the development of psoriasis through non-canonical Wnt signaling pathway

Background: The extensive involvement of microRNAs (miRNAs) in the pathogenesis of psoriasis is well documented. However, whether the serum exosome derived miRNAs play a role in psoriasis remains unclear. Objectives: To explore the role of serum exosome microRNA-1305 (miR-1305) in psoriasis. Methods: Exosomes were isolated from serum by differential ultracentrifugation. The morphology was identified by transmission electron microscope (TEM). Observation of serum exosomes uptake by keratinocytes though confocal fluorescence microscopy. MiRNA microarray was performed in serum exosomes from 4 patients with psoriasis and 4 controls. qRT-PCR were used to identify the differential expression miRNAs. Using bioinformatic predicted the signaling pathways related to mir-1305. Western blot was used to investigate the protein levels of Wnt5a and its downstream effectors. Normal human epidermal keratinocytes (NHEKs) and HaCat cells were transfected with miR-1305 mimic/Ctrl (50 nM) or miR-1305 inhibitor/Ctrl (100 nM); or siWnt5a/ctrl (60 nM) with Lipofectamine 2000. Results: The diameter of serum exosomes were around 100 nm. Serum exosomes could be uptake by keratinocytes after co-culture for 12h. Using miRNA microarray, we found 16 differentially expressed miRNAs in serum exosomes; 14 (87.5%) were downregulated and 2 (12.5%) were upregulated (fold change>2, P<0.05). Among these differentially expressed miRNAs, miR-1305 was down-regulated in serum exosomes from psoriasis patients (fold change=0.20, P<0.01, n=4). Through the methods of bioinformatics analysis, qRT-PCR and Western blot, we found that miR-1305 was closely related to non-canonical WNT signaling pathway (P<0.01), and miR-1305 regulated the expression of Wnt5a in Normal human epidermal keratinocytes (NHEKs) and HaCat cells. Conclusions: MiR-1305 was downregulated in serum exosomes from psoriasis patients. Downregulation of serum exosomes miR-1305 was involved in the pathogenesis of psoriasis through regulating non-canonical WNT pathways. However, much work remains to be done in the future to test our point of view.

Heme Oxygenase-1 Suppresses Wnt Signaling Pathway in Nonalcoholic Steatohepatitis-Related Liver Fibrosis.

Methods Mice were fed with a methionine-choline-deficient (MCD) diet for 8 weeks to induce steatohepatitis-related liver fibrosis and were treated with HO-1 inducer Hemin and inhibitor ZnPP. Mouse sera were collected for the biochemical analysis, and livers were obtained for further histological observation and gene expression analysis. HSC-T6 cells were cultured for the in vitro study and were administrated with Hemin and si-HO-1 to induce or inhibit the expression of HO-1. qPCR and Western blot were used to assess the mRNA and protein levels of genes. Results MCD-fed mice developed marked macrovesicular steatosis, focal necrosis, and inflammatory infiltration and pericellular fibrosis in liver sections. Administration of Hemin could significantly ameliorate the severity of steatosis, inflammation, and fibrosis and also could decrease the serum ALT and AST. We demonstrated that HO-1 induction was able to downregulate the key regulator of the canonical Wnt pathway Wnt1 and the noncanonical Wnt pathway Wnt5a. The downstream factors of the Wnt pathway β-catenin and NFAT5 were inhibited by Hemin, but GSK-3β was upregulated compared to the MCD group, which were consistent with the in vitro study. Hemin markedly inhibited the TGF-β1/Smad signaling pathway in both in vivo and in vitro studies. Conclusion Our study demonstrated that HO-1 inhibited the activation of canonical and noncanonical Wnt signaling pathways in NASH-related liver fibrosis. Thus, these results may suggest a new therapeutic strategy for NASH-related liver fibrosis.

Wnt signalling pathway and tau phosphorylation: A comprehensive study on known connections.

The Wnt pathway is the most important cascade in the nervous system; evidence has indicated that deregulation of the Wnt pathway induced pathogenic hallmarks of neurodegenerative diseases. Glycogen synthase kinase-3β (GSK-3β) as the main member of the Wnt pathway increases tau inclusions, the main marker in the neurodegenerative diseases. Phosphorylated tau is observed in the pre-tangle of the neurons in the early stage of neurodegenerative diseases. The researchers always try to improve pharmacological approaches of new therapeutic strategies to the treatment of neurodegenerative diseases that are required to represent a significant entry point by understanding the theoretical interactions of the molecular pathways. In this review, we have discussed the recent knowledge about the canonical and non-canonical Wnt signalling pathway, GSK-3β, Wnt/β-catenin antagonists, tau phosphorylation, and their important roles in the neurodegenerative diseases.

The effects of chronic cadmium exposure on the gut of Bufo gargarizans larvae at metamorphic climax: Histopathological impairments, microbiota changes and intestinal remodeling disruption.

Cadmium (Cd) is carcinogenic to human and it also has adverse effects on aquatic life such as amphibian larvae. However, its influences on amphibian gut morphology and development as well as intestinal microbiota are still hardly understood. In this study, we examined the effects of chronic cadmium exposure on the gut of tadpoles at Gosner stage 42 of metamorphic climax by using Bufo gargarizans as a model species. Tadpoles were exposed to cadmium concentrations at 0, 5, 100 and 200μgL-1 from Gosner stage 26-42. The results showed that high cadmium (100 and 200μgL-1) exposure caused significant decrease of body length and weight but significant increase of intestinal length and weight. Moreover, severe histopathological damages were induced by high Cd exposure. In addition, microbial communities in the gut of tadpoles in high cadmium exposure groups were remarkably different from those in control group. Unexpectedly, species diversity and richness were higher in the intestinal microbiota of 200μgL-1 cadmium exposure group. Furthermore, the abundance of prevalent phyla, families and genera of intestinal microbiota were changed by cadmium exposure. Meanwhile, cadmium exposure perturbed gut renewal functions and the relative mRNA expression of genes involved in canonical and non-canonical Wnt signaling pathway was seriously affected by high cadmium exposure. We concluded that cadmium could be harmful to tadpole health by inducing intestinal histopathological damages, gut remodeling inhibition and intestinal microbiota alterations.

Wnt Signaling Drives Prostate Cancer Bone Metastatic Tropism and Invasion

Wnt signaling has been implicated as a driver of prostate cancer-related osteoblast differentiation, and previous studies have linked modifications in Wnt function with the induction of tumor metastasis. A unique aspect of prostate cancer bone metastases in mouse models is their relative predilection to the hindlimb (femur) compared to the forelimb (humerus). Comparative gene expression profiling was performed within the humerus and femur from non–tumor-bearing mice to evaluate differences in the microenvironments of these locations. This revealed the relative overexpression of the Wnt signaling inhibitors WIF1 and SOST in the humerus compared to the femur, with increased WNT5A expression in femur bone marrow, suggesting a coordinated upregulation of Wnt signals within the femur compared to the humerus. Conditioned medium (CM) from bone marrow stromal cells (HS-5 cells) was used to mimic the bone marrow microenvironment, which strongly promoted prostate cancer cell invasion (3.3-fold increase in PC3 cells, P < .05; 7-fold increase in LNCaP cells, P < .05). WNT5A shRNA knockdown within the CM-producing HS-5 cells significantly decreased PC3 (56%, P < .05) and LNCaP (60%, P < .05) cell invasion. Similarly, preincubation of CM with WIF1 significantly blocked LNCaP cell invasion (40%, P < .05). shRNA-mediated knockdown of the Wnt receptors FZD4 and FZD8 also strongly inhibited tumor cell invasion (60% inhibition shFZD4, P < .05; 63% shFZD8, P < .05). Furthermore, small molecule inhibition of JNK, which is an important component of the noncanonical Wnt signaling pathway, significantly inhibited CM-mediated tumor invasion. Overall, this study reveals a role for Wnt signaling as a driver of prostate cancer bone metastatic tropism and invasion.

3, 3′, 5-Triiodo-L-thyronine affects polarity proteins of bovine Sertoli cells via WT1/non-canonical Wnt signaling pathway

To determine the role of 3, 3′, 5-triiodo-L thyroxine (T3) in the differentiation of Sertoli cells (SCs) and the factors influencing maturity via the Wilms’ tumor 1 (WT1)/non-canonical Wnt signaling pathway, high purity SCs were isolated from newborn calves’ testes and cultured in vitro. The SCs were stimulated with T3, and co-treated with short interference (si) RNA to knockdown endogenous WT1 and non-canonical Wnt signalling inhibitor Wnt-c59. Our results suggested that the addition of different concentrations (0, 25, 50, and 100 nM) of T3 in the culture medium changed the expression of KRT-18 (SCs immature marker) and accelerated the differentiation of SCs. T3 (100 nM) treatment induced up-regulated expression of WT1 over time (p < 0.05), while the expression of polarity proteins (Par3, Par6b, and E-cadherin) and Wnt4 were affected to varying degrees (p < 0.05). SCs were treated simultaneously with T3 + Wnt-c59 and T3 + WT1 siRNA, and the results showed that T3 could affect the expression of polarity proteins via WT1/non-canonical Wnt signaling pathway. These data put together indicate that T3 plays a dependent role in the induction of bovine SCs differentiation via WT1/non-canonical Wnt signaling pathway in vitro. This study proposes for the first time that WT1 is a major target for T3.

Wilms' tumour 1 (WT1) negatively regulates the expression of connexin 43 via a non-canonical Wnt signalling pathway in cultured bovine Sertoli cells.

The gap junction protein connexin (Cx) 43 between adjacent Sertoli cells (SCs) is the main testicular factor regulating the growth and development of SCs, and plays a vital role in controlling cell differentiation and maturation. However, the endogenous testicular factors that regulate Cx43 and the downstream signalling pathways that mediate Cx43-dependent SC differentiation are unclear. In this study, high-purity SCs were isolated from newborn calves' testes by differential adherence. The SCs were then cultured invitro and treated with short interference RNA to knockdown endogenous Wilms' tumour 1 (WT1). In WT1-knockdown SCs, Cx43 expression was upregulated. To elucidate the intracellular signalling mechanism of Cx43 in the differentiation and maturation of immature SCs, SCs were treated simultaneously with non-canonical Wnt signalling inhibitors CCG-1423 and GO-6983; in these SCs, Cx43 expression was upregulated. Together, these data indicate that WT1 negatively regulates the expression of Cx43 produced from SCs via a non-canonical Wnt signalling pathway in cultured bovine SCs.

Wnt Signaling: Paths for Cancer Progression.

The Wnt signaling pathways are well known for having several pivotal roles during embryonic development. However, the same developmental signaling pathways also present key roles in cancer initiation and progression. In this chapter, several issues regarding the roles of both canonical and non-canonical Wnt signaling pathways in cancer will be explored, mainly concerning their role in the maintenance of cancer stemness, in the metabolism reprograming of cancer cells and in the modulation of the tumor microenvironment. The role of Wnt signaling cascades in the response of cancer cells to anti-cancer treatments will be also discussed, as well as its potential therapeutic targeting during cancer treatment. Collectively, increasing evidence has been supporting pivotal roles of Wnt signaling in several features of cancer biology, however; a lot is still to be elucidated.

Wnt Network: A Brief Review of Pathways and Multifunctional Components.

The Wnt signaling pathway appears to activate intracellular signaling transduction in embryonic development, cell migration, hematopoiesis, and several diseases. Wnt signaling is basically recognized as a canonical β-catenin-dependent signaling pathway. However, in recent years, generally three Wnt-mediated pathways have been investigated, which operate independently of β-catenin and include calcium/calmodulin-dependent kinase II and protein kinase C, planar cell polarity, and a third one recruits hetrotrimeric GTP-binding proteins to stimulate phospholipase C and phosphodiesterase. We provide an overview of the noncanonical Wnt signaling pathway and then will focus on canonical Wnt signaling components, Wnt ligands, agonists, and antagonist. This review will also discuss β-catenin, both cytoplasmic and nuclear mechanisms, through signaling transduction, and, as a consequence, we have briefly highlighted potential implications of Wnt/β-catenin in some cancers.

RYK, a receptor of noncanonical Wnt ligand Wnt5a, is positively correlated with gastric cancer tumorigenesis and potential of liver metastasis.

Gastric cancer (GC) is the most prevalent human cancer around the globe. In GC, Wnt signaling is deregulated, and receptor-like tyrosine kinase (RYK) coreceptors have been identified to interact with noncanonical Wnt ligand Wnt5a. We, therefore, aimed to evaluate the role of RYK in GC development and metastasis. GC tumor samples were collected from 250 GC patients. Expressions of RYK, as well as markers for the epithelial-mesenchymal transition (EMT), such as N-cadherin and E-cadherin, were subjected to correlation analysis with clinicopathological features. Endogenous RYK expression levels were compared in GC cell lines with ascending metastatic potentials followed by stable RYK knockdown. Effect of RYK knockdown on GC cell migration, invasion, and EMT phenotype were assessed in vitro, and on GC tumor growth in vivo in a xenograft rodent model. Particularly, liver metastasis potential of tail vein-injected GC cells was also analyzed following RYK knockdown. RYK was highly correlated with liver metastasis of GC tumors and the expression profiles of EMT markers toward the mesenchymal tendency. RYK expression was also positively correlated with the metastasis potential of GC cells. RYK knockdown not only inhibited migration, invasion, and EMT of GC cells in vitro, but also suppressed tumorigenesis and liver metastasis of GC cells in vivo using the mouse xenograft model. RYK is highly correlated with GC tumorigenesis and potential of liver metastasis, suggesting it may be a novel oncogenic factor of the noncanonical Wnt signaling pathway contributing to GC.NEW & NOTEWORTHY RYK is highly correlated with gastric cancer tumorigenesis and the potential of liver metastasis, suggesting it may be a novel oncogenic factor of the noncanonical Wnt signaling pathway contributing to gastric cancer.

The Mechanism, Regulatory Effect of Wnt5α/Ca2+ Signaling Pathway on hMSCs Osteogenic Differentiation Under Infection Conditions

Background: The paper aimed to reveal the role and possible regulatory mechanisms of Wnt5 gene and its non-canonical Beta-catenin signaling pathway in osteogenic differentiation and bone repairment of hMSCs under infection environment. Material and Methods : CCK-8 method was employed to detect the effect of SPA on the proliferation of different hMSCs cells. The histological staining of alizarin red was used to observe the differentiation of cells into osteoblasts. The semi-quantitative detection of osteoblast alkaline phosphatase (ALP) was performed. Fluo-2 assay was employed to measure the intracellular calcium concentration of different hMSCs before and after osteogenic differentiation stimulated by SPA. RT-PCR was applied to detect the specific gene fluorescence of osteoblasts differentiation. Western Blotting was employed to determine the differentiation of hMSCs into osteoblasts. Results: Different hMSCs were able to proliferate in vitro under the stimulation of 100 ng/mL SPA. CCK-8 kit was used to detect lentivirus-infected hMSCs and non-transduced hMSCs in vitro. The results showed that all the cells gradually proliferate with time and an increasing rate. The hMSCs treated with different Wnt5 genes were stained with alizarin red after osteogenic differentiation, and the activities of AMSCs ALP increased. The intracellular free calcium concentration increased with the induction time and peaked in the Wnt5 overexpression group. PCR results showed that ALP, Runx-2, Collagen I, OC, Osterix and BSP genes were all increased in contrast with the non-induction Control group. Conclusion: Under the inflammatory condition of SPA virulence factors, non-canonical Wnt signaling pathway is associated with the classical Wnt/ β-catenin signaling pathway in the process of osteogenic differentiation of hMSCs in vitro, which has a certain synergistic effect.

Wnt5a promotes differentiation and development of adult-born neurons in the hippocampus by noncanonical Wnt signaling.

In the adult hippocampus, new neurons are generated in the dentate gyrus. The Wnt signaling pathway regulates this process, but little is known about the endogenous Wnt ligands involved. We investigated the role of Wnt5a on adult hippocampal neurogenesis. Wnt5a regulates neuronal morphogenesis during embryonic development, and maintains dendritic architecture of pyramidal neurons in the adult hippocampus. Here, we determined that Wnt5a knockdown in the mouse dentate gyrus by lentivirus-mediated shRNA impaired neuronal differentiation of progenitor cells, and reduced dendritic development of adult-born neurons. In cultured adult hippocampal progenitors (AHPs), Wnt5a knockdown reduced neuronal differentiation and morphological development of AHP-derived neurons, whereas treatment with Wnt5a had the opposite effect. Interestingly, no changes in astrocytic differentiation were observed in vivo or in vitro, suggesting that Wnt5a does not affect fate-commitment. By using specific inhibitors, we determined that Wnt5a signals through CaMKII to induce neurogenesis, and promotes dendritic development of newborn neurons through activating Wnt/JNK and Wnt/CaMKII signaling. Our results indicate Wnt5a as a niche factor in the adult hippocampus that promotes neuronal differentiation and development through activation of noncanonical Wnt signaling pathways.