Suppression of Wnt/ß-catenin Signaling in PDAC via METTL16-mediated N6-methyladenosine Modification of DVL2.

Pancreatic cancer is a formidable cause of cancer-related deaths worldwide and has witnessed a more than twofold increase in incidence over the last 25 years. The most frequently occurring form of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC), accounting for the majority of pancreatic cancer cases. N6-methyladenosine (m6A), the most abundant transcript modification, has been implicated in the pathogenesis of numerous human cancers, including pancreatic cancer. Despite this, the functional role of methyltransferase-like 16 (METTL16), a critical m6A methyltransferase, in PDAC remains elusive. In this study, we demonstrate that METTL16 expression is significantly diminished in PDAC, rendering it a promising prognostic indicator. Strikingly, both in vitro and in vivo assays revealed accelerated metastasis and invasion of PDAC cells upon METTL16 knockdown, while overexpression of METTL16 exerted an opposite effect. Mechanistically, METTL16 regulates DVL2 expression by suppressing its translation via m6A modification, thereby regulating Wnt/ß-catenin signaling., Our results unveil the downregulation of METTL16 as a concomitant increase in DVL2 levels via m6A modification promoting the progression of PDAC. Thus, we propose METTL16 as a novel therapeutic candidate for targeted PDAC treatment.

Network Pharmacology and Molecular Docking Analysis on Molecular Targets and Mechanisms of Fei Jin Sheng Formula in the Treatment of Lung Cancer.

BACKGROUND: Fei Jin Sheng Formula (FJSF) is widely used in clinical treatment of lung cancer. But the underlying active ingredients and mechanisms are unclear. OBJECTIVE: To investigate the active components and functional mechanisms of FJSF in treating lung cancer using a network pharmacology approach and molecular docking combined with vitro experiments Methods: Based on the TCMSP and related literature, the chemical components of related herbs in FJSF were collected. The active components of FJSF were screened by ADME parameters, and the targets were predicted by the Swiss Target Prediction database. The "drug-active ingredient-target" network was constructed by Cytoscape. Disease-related targets of lung cancer were acquired from GeneCards, OMIM, and TTD databases. Then drug-disease intersection target genes were obtained through the Venn tool. GO analysis and KEGG pathway enrichment analysis were performed via the Metascape database. Cytoscape was used to construct a PPI network and perform topological analysis. Kaplan-Meier Plotter was used to analyze the relationship between DVL2 and the prognosis of lung cancer patients. xCell method was used to estimate the relationship between DVL2 and immune cell infiltration in lung cancer. Molecular docking was performed by AutoDockTools-1.5.6. The results were verified by experiments in vitro. RESULTS: FJSF contained 272 active ingredients and 52 potential targets for lung cancer. GO enrichment analysis is mainly related to cell migration and movement, lipid metabolism, and protein kinase activity. KEGG pathway enrichment analysis mainly involves PI3K-Akt, TNF, HIF-1, and other pathways. Molecular docking shows that the compound Xambioona, quercetin and methyl palmitate in FJSF has a strong binding ability with NTRK1, APC, and DVL2. Analysis of the data in UCSC to analyze the expression of DVL2 in lung cancer shows that DVL2 was overexpressed in lung adenocarcinoma tissues. Kaplan-Meier analysis shows that the higher DVL2 expression in lung cancer patients was associated with poorer overall survival and poorer survival in stage I patients. It was negatively correlated with the infiltration of various immune cells in the lung cancer microenvironment. Vitro Experiment showed that Methyl Palmitate (MP) can inhibit the proliferation, migration, and invasion of lung cancer cells, and its mechanism of action may be to downregulate the expression of DVL2. CONCLUSION: FJSF may play a role in inhibiting the occurrence and development of lung cancer by downregulating the expression of DVL2 in A549 cells through its active ingredient Methyl Palmitate. These results provide scientific evidence for further investigations into the role of FJSF and Methyl Palmitate in the treatment of lung cancer.

Dishevelled segment polarity protein 2 promotes gastric cancer progression through Wnt/ß-catenin pathway.

Dishevelled family proteins (DVL1-3), key scaffold proteins, act on canonical and non-canonical Wnt/ß-catenin signaling pathway. DVL has been implicated in various tumor progression. However, its role and underlying mechanisms in gastric cancer (GC) remain unclear. The aim of this study was to investigate the role of DVL in GC development using cell lines and 209 GC specimens. We analyzed three orthologs of DVL in GC tissues and paired adjacent non-tumor tissues, and only DVL2 is highly expressed in GC tissues. We also analyzed clinicopathological data on DVL2 expression in gastric cancer specimens. In immunohistochemistry, DVL2 expression was up-regulated in GC tissues compared with paired adjacent non-tumor tissues (153/209, 73.2%). DVL2 expression level was significantly correlated with many clinicopathological parameters such as T stage (P < 0.001) and N stage (P < 0.001). Survival analysis showed that the overall survival (OS) of patients with high expression of DVL2 was significantly shorter than those with low expression. Multivariate Cox regression analysis revealed that DVL2 expression was an important and independent prognostic factor for gastric cancer patients (P = 0.011, HR=1.78, 95%CI (1.14-2.79). Depletion of endogenous DVL2 using short hairpin RNA (shRNA) inhibited GC cell proliferation, migration, and invasion. The abnormal activation of Wnt/ß-catenin signaling pathway is mainly achieved through the abnormal expression of DVL2. DVL2 is highly expressed in gastric cancer tissues, which may be a new independent risk factor for the prognosis of gastric cancer patients. In gastric cancer, DVL2 overexpression plays a crucial role in the occurrence and development of gastric cancer, so it may become a new, effective and complementary therapeutic target for gastric cancer.

Exosomal circ_0091741 promotes gastric cancer cell autophagy and chemoresistance via the miR-330-3p/TRIM14/Dvl2/Wnt/ß-catenin axis.

The importance of cancer cell-released exosomes in the treatment of various cancers has been well-characterized. The current study aims to examine the potential biological functions of gastric cancer (GC) cell-released exosomes delivering a novel circRNA circ_0091741 in GC and the underlying molecular mechanism. Expression of circ_0091741 was examined in the GC cells, (OXA)-resistant HGC-27 (HGC-27/OXA) cells, and isolated exosomes, after which its downstream miRNA was analyzed. The role and mechanism of the circ_0091741 transmitted by GC cells-derived exosomes in GC cell autophagy and chemoresistance were assessed using various molecular biological methods. A mouse tumor xenograft model was prepared to discern the effect of circ_0091741 on tumorigenesis in vivo. GC cells and their exosomes were characterized by upregulated circ_0091741 expression. circ_0091741 transferred by GC cell-derived exosomes induced the autophagy and OXA resistance of GC cells. circ_0091741 obstructed the binding of miR-330-3p to TRIM14 and increased the expression of TRIM14. TRIM14 could cause activation of the Wnt/ß-catenin signaling pathway by stabilizing Dvl2. By this mechanism, the autophagy and OXA resistance of GC cells were augmented. In vivo assay unfolded that orthotopic implantation of exosomal circ_0091741 overexpressed GC cells into nude mice enhanced tumorigenesis. In conclusion, our study emphasized the promotive role of exosomal circ_0091741 in autophagy and chemoresistance of GC cells, thus laying the basis for the development of novel therapeutic targets for GC treatment.

CYP2E1 plays a suppressive role in hepatocellular carcinoma by regulating Wnt/Dvl2/ß-catenin signaling.

OBJECTIVE: Knowledge of the role of CYP2E1 in hepatocarcinogenesis is largely based on epidemiological and animal studies, with a primary focus on the role of CYP2E1 in metabolic activation of procarcinogens. Few studies have directly assessed the effects of CYP2E1 on HCC malignant phenotypes. METHODS: The expression of CYP2E1 in HCC tissues was determined by qRT-PCR, western blotting and immunohistochemistry. Overexpression of CYP2E1 in HCC cell was achieved by lentivirus transfection. The function of CYP2E1 were detected by CCK-8, wound healing, transwell assays, xenograft models and pulmonary metastasis model. TOP/FOPFlash reporter assay, western blotting, functional rescue experiments, Co-immunoprecipitation and reactive oxygen species detection were conducted to reveal the underlying mechanism of the tumor suppressive role of CYP2E1. RESULTS: CYP2E1 expression is down-regulated in HCC tissues, and this downregulation was associated with large tumor diameter, vascular invasion, poor differentiation, and shortened patient survival time. Ectopic expression of CYP2E1 inhibits the proliferation, invasion and migration and epithelial-to-mesenchymal transition of HCC cells in vitro, and inhibits tumor formation and lung metastasis in nude mice. Mechanistic investigations show that CYP2E1 overexpression significantly inhibited Wnt/ß-catenin signaling activity and decreased Dvl2 expression in HCC cells. An increase in Dvl2 expression restored the malignant phenotype of HCC cells. Notably, CYP2E1 promoted the ubiquitin-mediated degradation of Dvl2 by strengthening the interaction between Dvl2 and the E3 ubiquitin ligase KLHL12 in CYP2E1-stable HCC cells. CYP2E1-induced ROS accumulation was a critical upstream event in the Wnt/ß-Catenin pathway in CYP2E1-overexpressing HCC cells. CONCLUSIONS: These results provide novel insight into the role of CYP2E1 in HCC and the tumor suppressor role of CYP2E1 can be attributed to its ability to manipulate Wnt/Dvl2/ß-catenin pathway via inducing ROS accumulation, which provides a potential target for the prevention and treatment of HCC.

DIX domain containing 1 (DIXDC1) modulates VEGFR2 level in vasculatures to regulate embryonic and postnatal retina angiogenesis.

BACKGROUND: In sprouting angiogenesis, VEGFR2 level is regulated via a fine-tuned process involving various signaling pathways. Other than VEGF/VEGFR2 signaling pathway, Wnt/ ß-catenin signaling is also important in vascular development. However, the crosstalk between these two signaling pathways is still unknown to date. In this study, we aimed to investigate the role of DIX domain containing 1 (DIXDC1) in vasculature, facilitating the crosstalk between VEGF/VEGFR2 and Wnt/ ß-catenin signaling pathways. RESULTS: In mice, DIXDC1 deficiency delayed angiogenesis at the embryonic stage and suppressed neovascularization at the neonatal stage. DIXDC1 knockdown inhibited VEGF-induced angiogenesis in endothelial cells in vitro by downregulating VEGFR2 expression. DIXDC1 bound Dishevelled Segment Polarity Protein 2 (Dvl2) and polymerized Dvl2 stabilizing VEGFR2 protein via its direct interaction. The complex formation and stability of VEGFR2 was potentiated by Wnt signaling. Moreover, hypoxia elevated DIXDC1 expression and likely modulated both canonical Wnt/ß-catenin signaling and VEGFR2 stability in vasculatures. Pathological angiogenesis in DIXDC1 knockout mice was decreased significantly in oxygen-induced retinopathy (OIR) and in wound healing models. These results suggest that DIXDC1 is an important factor in developmental and pathological angiogenesis. CONCLUSION: We have identified DIXDC1 as an important factor in early vascular development. These results suggest that DIXDC1 represents a novel regulator of sprouting angiogenesis that links Wnt signaling and VEGFR2 stability and may have a potential role in pathological neovascularization.

DACT3 has a tumor-inhibiting role in acute myeloid leukemia via the suppression of Wnt/ß-catenin signaling by DVL2.

Dapper antagonist of catenin-3 (DACT3) is a new tumor-related protein associated with a diverse set of tumors. However, whether DACT3 plays a role in acute myeloid leukemia (AML) is not fully understood. Our findings showed low DACT3 level in AML tissue, which was corrected with shorter survival rates. Upregulation of DACT3 effectively repressed cellular proliferation, and promoted cell cycle arrest and apoptosis of AML cells. Upregulation of DACT3 decreased levels of Dishevelled2 (DVL2), phospho-glycogen synthase kinase-3ß (GSK-3ß), and active ß-catenin, which collectively suppressed Wnt/ß-catenin-mediated transcriptional activity. Overexpression of DVL2 reversed DACT3-mediated suppression of Wnt/ß-catenin pathway. Reactivation of Wnt/ß-catenin abrogated DACT3-upregulation-evoked tumor-suppression in AML cells. Overexpression of DACT3 impeded the formation and growth of AML-derived xenograft tumor. Collectively, our work reveals a tumor-suppressive role of DACT3, a protein that negatively adjusts Wnt/ß-catenin pathway via downregulation of DVL2 in AML.

Novel pathogenic variants and quantitative phenotypic analyses of Robinow syndrome: WNT signaling perturbation and phenotypic variability.

Robinow syndrome (RS) is a genetically heterogeneous disorder with six genes that converge on the WNT/planar cell polarity (PCP) signaling pathway implicated (DVL1, DVL3, FZD2, NXN, ROR2, and WNT5A). RS is characterized by skeletal dysplasia and distinctive facial and physical characteristics. To further explore the genetic heterogeneity, paralog contribution, and phenotypic variability of RS, we investigated a cohort of 22 individuals clinically diagnosed with RS from 18 unrelated families. Pathogenic or likely pathogenic variants in genes associated with RS or RS phenocopies were identified in all 22 individuals, including the first variant to be reported in DVL2. We retrospectively collected medical records of 16 individuals from this cohort and extracted clinical descriptions from 52 previously published cases. We performed Human Phenotype Ontology (HPO) based quantitative phenotypic analyses to dissect allele-specific phenotypic differences. Individuals with FZD2 variants clustered into two groups with demonstrable phenotypic differences between those with missense and truncating alleles. Probands with biallelic NXN variants clustered together with the majority of probands carrying DVL1, DVL2, and DVL3 variants, demonstrating no phenotypic distinction between the NXN-autosomal recessive and dominant forms of RS. While phenotypically similar diseases on the RS differential matched through HPO analysis, clustering using phenotype similarity score placed RS-associated phenotypes in a unique cluster containing WNT5A, FZD2, and ROR2 apart from non-RS-associated paralogs. Through human phenotype analyses of this RS cohort and OMIM clinical synopses of Mendelian disease, this study begins to tease apart specific biologic roles for non-canonical WNT-pathway proteins.

Dvl2 facilitates the coordination of NF-κB and Wnt signaling to promote colitis-associated colorectal progression.

Colitis-associated colorectal cancer (CAC) arises due to prolonged inflammation and has distinct molecular events compared with sporadic colorectal cancer (CRC). Although inflammatory NF-κB signaling was activated by pro-inflammatory cytokines (such as TNFα) in early stages of CAC, Wnt/ß-catenin signaling later appears to function as a key regulator of CAC progression. However, the exact mechanism responsible for the cross-regulation between these 2 pathways remains unclear. Here, we found reciprocal inhibition between NF-κB and Wnt/ß-catenin signaling in CAC samples, and the Dvl2, an adaptor protein of Wnt/ß-catenin signaling, is responsible for NF-κB inhibition. Mechanistically, Dvl2 interacts with the C-terminus of tumor necrosis factor receptor 1 (TNFRI) and mediates TNFRI endocytosis, leading to NF-κB signal inhibition. In addition, increased infiltration of the pro-inflammatory cytokine interleukin-13 (IL-13) is responsible for upregulating Dvl2 expression through STAT6. Targeting STAT6 effectively decreases Dvl2 levels and restrains colony formation of cancer cells. These findings demonstrate a unique role for Dvl2 in TNFRI endocytosis, which facilitates the coordination of NF-κB and Wnt to promote CAC progression.

WWP1 Deficiency Alleviates Cardiac Remodeling Induced by Simulated Microgravity.

Cardiac muscle is extremely sensitive to changes in loading conditions; the microgravity during space flight can cause cardiac remodeling and function decline. At present, the mechanism of microgravity-induced cardiac remodeling remains to be revealed. WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) is an important activator of pressure overload-induced cardiac remodeling by stabilizing disheveled segment polarity proteins 2 (DVL2) and activating the calcium-calmodulin-dependent protein kinase II (CaMKII)/histone deacetylase 4 (HDAC4)/myocyte-specific enhancer factor 2C (MEF2C) axis. However, the role of WWP1 in cardiac remodeling induced by microgravity is unknown. The purpose of this study was to determine whether WWP1 was also involved in the regulation of cardiac remodeling caused by microgravity. Firstly, we detected the expression of WWP1 and DVL2 in the heart from mice and monkeys after simulated microgravity using western blotting and immunohistochemistry. Secondly, WWP1 knockout (KO) and wild-type (WT) mice were subjected to tail suspension (TS) to simulate microgravity effect. We assessed the cardiac remodeling in morphology and function through a histological analysis and echocardiography. Finally, we detected the phosphorylation levels of CaMKII and HDAC4 in the hearts from WT and WWP1 KO mice after TS. The results revealed the increased expression of WWP1 and DVL2 in the hearts both from mice and monkeys after simulated microgravity. WWP1 deficiency alleviated simulated microgravity-induced cardiac atrophy and function decline. The histological analysis demonstrated WWP1 KO inhibited the decreases in the size of individual cardiomyocytes of mice after tail suspension. WWP1 KO can inhibit the activation of the DVL2/CaMKII/HDAC4 pathway in the hearts of mice induced by simulated microgravity. These results demonstrated WWP1 as a potential therapeutic target for cardiac remodeling and function decline induced by simulated microgravity.

Pellino-2 in nonimmune cells: novel interaction partners and intracellular localization.

Pellino-2 is an E3 ubiquitin ligase that mediates intracellular signaling in innate immune pathways. Most studies of endogenous Pellino-2 have been performed in macrophages, but none in nonimmune cells. Using yeast two-hybrid screening and co-immunoprecipitation, we identified six novel interaction partners of Pellino-2, with various localizations: insulin receptor substrate 1, NIMA-related kinase 9, tumor necrosis factor receptor-associated factor 7, cyclin-F, roundabout homolog 1, and disheveled homolog 2. Pellino-2 showed cytoplasmic localization in a wide range of nonimmune cells under physiological potassium concentrations. Treatment with the potassium ionophore nigericin resulted in nuclear localization of Pellino-2, which was reversed by the potassium channel blocker tetraethylammonium. Live-cell imaging revealed intracellular migration of GFP-tagged Pellino-2. In summary, Pellino-2 interacts with proteins at different cellular locations, taking part in dynamic processes that change its intracellular localization influenced by potassium efflux.

Aberrant expression of SFRP1, SFRP3, DVL2 and DVL3 Wnt signaling pathway components in diffuse gastric carcinoma.

Diffuse gastric carcinoma (DGC) is characterized by poorly cohesive cells, highly invasive growth patterns, poor prognosis and resistance to the majority of available systemic therapeutic strategies. It has been previously reported that the Wnt/ß-catenin signaling pathway serves a prominent role in the tumorigenesis of gastric carcinoma. However, the mechanism underlying the dysregulation of this pathway in DGC has not been fully elucidated. Therefore, the present study aimed to investigate the expression profiles of Wnt antagonists, secreted frizzled-related protein 1 (SFRP1) and secreted frizzled-related protein 3 (SFRP3), and dishevelled protein family members, dishevelled segment polarity protein 2 (DVL2) and dishevelled segment polarity protein 3 (DVL3), in DGC tissues. The association between the expression levels of these factors and the clinicopathological parameters of the patients was determined. Protein and mRNA expression levels in 62 DGC tumor tissues and 62 normal gastric mucosal tissues obtained from patients with non-malignant disease were measured using immunohistochemical and reverse transcription-quantitative PCR (RT-qPCR) analysis. Significantly lower protein expression levels of SFRP1 (P<0.001) and SFRP3 (P<0.001), but significantly higher protein expression levels of DVL2 (P<0.001) and DVL3 (P<0.001) were observed in DGC tissues compared with in control tissues by immunohistochemistry. In addition, significantly lower expression levels of SFRP1 (P<0.05) and higher expression levels of DVL3 (P<0.05) were found in in DGC tissues compared with those in normal gastric mucosal tissues using RT-qPCR. According to correlation analysis between the SFRP1, SFRP3, DVL2 and DVL3 protein expression levels and the clinicopathological characteristics of patients with DGC, a statistically significant correlation was found between the SFRP3 volume density and T stage (r=0.304; P=0.017) and between the SFRP3 volume density and clinical stage (r=0.336; P=0.008). In conclusion, the findings of the present study suggested that the Wnt signaling pathway components SFRP1, SFRP3, DVL2 and DVL3 may be aberrantly expressed in DGC tissues, implicating their possible role in the development of this malignant disease. The present data also revealed a positive relationship between SFRP3 protein expression and the clinical and T stage of DGC.

ASPM promotes hepatocellular carcinoma progression by activating Wnt/ß-catenin signaling through antagonizing autophagy-mediated Dvl2 degradation.

Hepatocellular carcinoma (HCC) is one of the most fatal cancers worldwide. In this article, we show that expression of abnormal spindle-like microcephaly-associated protein (ASPM) is up-regulated in liver cancer samples, and this up-regulation is significantly associated with tumor aggressiveness and reduced survival times of patients. Down-regulation of ASPM expression inhibits the proliferation, invasion, migration and epithelial-to-mesenchymal transition of HCC cells in vitro and inhibits tumor formation in nude mice. ASPM interacts with disheveled-2 (Dvl2) and antagonizes autophagy-mediated Dvl2 degradation by weakening the functional interaction between Dvl2 and the lipidated form of microtubule-associated proteins 1A/1B light chain 3A (LC3II), thereby increasing Dvl2 protein abundance and leading to Wnt/ß-catenin signaling activation in HCC cells. Thus, our results define ASPM as a novel oncoprotein in HCC and indicate that disruption of the Wnt-ASPM-Dvl2-ß-catenin signaling axis might have potential clinical value.

Cullin 1 (CUL1) Promotes Primary Ciliogenesis through the Induction of Ubiquitin-Proteasome-Dependent Dvl2 Degradation.

Primary cilia are nonmotile cellular signal-sensing antenna-like structures composed of microtubule-based structures that distinguish them from motile cilia in structure and function. Primary ciliogenesis is regulated by various cellular signals, such as Wnt, hedgehog (Hh), and platelet-derived growth factor (PDGF). The abnormal regulation of ciliogenesis is closely related to developing various human diseases, including ciliopathies and cancer. This study identified a novel primary ciliogenesis factor Cullin 1 (CUL1), a core component of Skp1-Cullin-F-box (SCF) E3 ubiquitin ligase complex, which regulates the proteolysis of dishevelled 2 (Dvl2) through the ubiquitin-proteasome system. Through immunoprecipitation-tandem mass spectrometry analysis, 176 Dvl2 interacting candidates were identified, of which CUL1 is a novel Dvl2 modulator that induces Dvl2 ubiquitination-dependent degradation. Neddylation-dependent CUL1 activity at the centrosomes was essential for centrosomal Dvl2 degradation and primary ciliogenesis. Therefore, this study provides a new mechanism of Dvl2 degradation by CUL1, which ultimately leads to primary ciliogenesis, and suggest a novel target for primary cilia-related human diseases.

Targeting E3 Ubiquitin Ligase WWP1 Prevents Cardiac Hypertrophy Through Destabilizing DVL2 via Inhibition of K27-Linked Ubiquitination.

BACKGROUND: Without adequate treatment, pathological cardiac hypertrophy induced by sustained pressure overload eventually leads to heart failure. WWP1 (WW domain-containing E3 ubiquitin protein ligase 1) is an important regulator of aging-related pathologies, including cancer and cardiovascular diseases. However, the role of WWP1 in pressure overload-induced cardiac remodeling and heart failure is yet to be determined. METHODS: To examine the correlation of WWP1 with hypertrophy, we analyzed WWP1 expression in patients with heart failure and mice subjected to transverse aortic constriction (TAC) by Western blotting and immunohistochemical staining. TAC surgery was performed on WWP1 knockout mice to assess the role of WWP1 in cardiac hypertrophy, heart function was examined by echocardiography, and related cellular and molecular markers were examined. Mass spectrometry and coimmunoprecipitation assays were conducted to identify the proteins that interacted with WWP1. Pulse-chase assay, ubiquitination assay, reporter gene assay, and an in vivo mouse model via AAV9 (adeno-associated virus serotype 9) were used to explore the mechanisms by which WWP1 regulates cardiac remodeling. AAV9 carrying cardiac troponin T (cTnT) promoter-driven small hairpin RNA targeting WWP1 (AAV9-cTnT-shWWP1) was administered to investigate its rescue role in TAC-induced cardiac dysfunction. RESULTS: The WWP1 level was significantly increased in the hypertrophic hearts from patients with heart failure and mice subjected to TAC. The results of echocardiography and histology demonstrated that WWP1 knockout protected the heart from TAC-induced hypertrophy. There was a direct interaction between WWP1 and DVL2 (disheveled segment polarity protein 2). DVL2 was stabilized by WWP1-mediated K27-linked polyubiquitination. The role of WWP1 in pressure overload-induced cardiac hypertrophy was mediated by the DVL2/CaMKII/HDAC4/MEF2C signaling pathway. Therapeutic targeting WWP1 almost abolished TAC induced heart dysfunction, suggesting WWP1 as a potential target for treating cardiac hypertrophy and failure. CONCLUSIONS: We identified WWP1 as a key therapeutic target for pressure overload induced cardiac remodeling. We also found a novel mechanism regulated by WWP1. WWP1 promotes atypical K27-linked ubiquitin multichain assembly on DVL2 and exacerbates cardiac hypertrophy by the DVL2/CaMKII/HDAC4/MEF2C pathway.

Vesicle transporter GOLT1B mediates the cell membrane localization of DVL2 and PD-L2 and promotes colorectal cancer metastasis.

BACKGROUND: Colorectal cancer (CRC) is the third most diagnosed and second leading cause of cancer death worldwide. Hallmark proteins processing is usually dysregulated in cancers. Finding key regulatory molecules is of great importance for CRC metastasis intervention. GOLT1B is a vesicle transport protein which is involved in cytosolic proteins trafficking. However, its role in cancer has never been addressed. METHODS: CRC cell lines and subcutaneous xenograft animal model were utilized to investigate the biological function of GOLT1B. Patients samples were used to validate the correlation between GOLT1B and clinical outcome. In vivo targeted delivery of GOLT1B-siRNA was investigated in PDX (Patient derived tumor xenograft) model. RESULTS: We found that GOLT1B was highly expressed in CRC, and was an independent prognostic marker of overall survival (OS) and progression free survival (PFS). GOLT1B could promote CRC metastasis in vitro and in vivo. GOLT1B overexpression could increase DVL2 level and enhance its plasma membrane translocation, which subsequently activated downstream Wnt/ß-catenin pathway and increase the nuclear ß-catenin level, hence induce epithelial-mesenchymal transition (EMT). In addition, GOLT1B could also interact with PD-L2 and increase its membrane level. Co-culture of GOLT1B-overexpresed CRC cells with Jurkat cells significantly induced T cells apoptosis, which might further promote cancer cell the migration and invasion. Further, targeted delivery of GOLT1B siRNA could significantly inhibit tumor progression in GOLT1B highly expressed PDX model. CONCLUSION: Taken together, our findings suggest that the vesicle transporter GOLT1B could promote CRC metastasis not only by assisting DVL2 translocation and activating Wnt/ß-catenin pathway, but also facilitating PD-L2 membrane localization to induce immune suppression. Targeted inhibition of GOLT1B could be a potential therapeutic strategy for CRC treatment.

Cyclin G2 upregulation impairs migration, invasion, and network formation through RNF123/Dvl2/JNK signaling in the trophoblast cell line HTR8/SVneo, a possible role in preeclampsia.

Disruption of extravillous trophoblast (EVT) migration and invasion is considered to be responsible for pathological placentation in preeclampsia (PE). Cyclin G2 (CCNG2) is an atypical cyclin that inhibits cell cycle progression. However, its biological function and underlying molecular mechanism in PE are poorly understood. In this study, clinical data demonstrated that CCNG2 was significantly upregulated in PE placenta and associated with invasive EVT dysfunction. Additionally, Ccng2 knockout led to an attenuation of PE-like symptoms in the PE mouse model produced via treatment with NG-nitro-L-arginine methyl ester (L-NAME). In vitro, CCNG2 inhibited the migration, invasion, and endothelial-like network formation of human trophoblast cell line HTR8/SVneo. Mechanically, CCNG2 suppressed JNK-dependent Wnt/PCP signaling and its downstream indicators including epithelial-to-mesenchymal transition (EMT) markers and matrix metalloproteinases (MMPs) via promoting the polyubiquitination degradation of dishevelled 2 (Dvl2) protein in HTR8/SVneo cells. We also discovered that the E3 ligase Ring finger protein 123 (RNF123), as a novel CCNG2 target among HTR8/SVneo cells, interacted with Dvl2 and participated in CCNG2-induced polyubiquitination degradation of Dvl2. Moreover, we verified that the treatment of HTR8/SVneo cells with RNF123-specific siRNA improved polyubiquitination-induced degradation of Dvl2 and the activity of Wnt/PCP-JNK signaling mediated by CCNG2. Taken together, our results reveal that the CCNG2/RNF123/Dvl2/JNK axis may be involved in the pathogenesis and progression of PE through trophoblastic cell function modulation, thus probably providing us with new therapeutic strategies for PE treatment.

PWP1 Promotes the Malignant Phenotypes of Lung Cancer Cells by Interacting with DVL2 and Merlin.

PURPOSE: The significance of periodic tryptophan protein 1 (PWP1) expression in human cancer and its molecular mechanism of action have not been reported so far. MATERIALS AND METHODS: Immunohistochemistry was performed to analyze the expression of PWP1 in non-small cell lung cancer (NSCLC) tissues and statistical analysis was applied to analyze the relationship between PWP1 expression and the clinicopathological factors. The effects of PWP1 on NSCLC proliferation and invasion were determined by colony formation, transwell and MTT assays. Western blot analysis (WB), dual-luciferase reporter gene assays and immunofluorescence staining were performed to demonstrate whether PWP1 stimulates Wnt pathway and inhibits Hippo pathway. Co-immunoprecipitation (Co-ip) assays were used to confirm the potential role of PWP1 in Wnt and Hippo signaling pathways. RESULTS: PWP1 expression in NSCLC was higher than that in normal bronchial epithelium and normal submucosal glands. In addition, PWP1 expression had a positive correlation with poor differentiation, high pathological tumor-node-metastasis (TNM) stage, and lymph node metastasis. Kaplan-Meier database demonstrated that the overall survival time of patients with high PWP1 expression was significantly shorter than that of patients with low PWP1 expression. Mechanistically, we found that PWP1 could interact with DVL2 to upregulate ß-catenin (thereby activating the Wnt pathway), whereas PWP1 could interact with Merlin (NF2) to downregulate p-MST1 (thereby inhibiting the Hippo signaling pathway). The effects of PWP1 on promoting the Wnt pathway or inhibiting the Hippo pathway were offset in DVL2- or Merlin-knockdown cells transiently overexpressing PWP1. CONCLUSION: PWP1 expression in NSCLC was correlated with poor prognosis. PWP1 enhanced the activity of the Wnt pathway by interacting with DVL2, whereas PWP1 inhibited the activity of the Hippo pathway by interacting with Merlin. Together, these two effects promoted the detrimental biological behaviors of NSCLC cells.

The Daple-CK1ε complex regulates Dvl2 phosphorylation and canonical Wnt signaling.

The canonical Wnt signaling pathway plays a crucial role in embryonic development, tissue homeostasis and cancer progression. The binding of Wnt ligands to their cognate receptors, the Frizzled (Fzd) family of proteins, recruits Dishevelled segment polarity protein (Dvl) to the plasma membrane and induces its phosphorylation via casein kinase 1 (CK1), which leads to the activation of ß-catenin. Previous studies showed that Dishevelled-associating protein with a high frequency of leucine residues (Daple) is an important component of the Wnt signaling pathway and essential for Dvl phosphorylation. However, the mechanism by which Daple promotes CK1-mediated phosphorylation of Dvl is not fully understood. In this study, we found that Daple overexpression induced CK1ε-mediated Dvl2 phosphorylation at threonine 224 (Thr224). A Daple mutant (Daple ΔGCV) that lacks a carboxyl-terminal motif to associate with Dvl, retained the ability to interact with CK1ε, but did not induce Dvl phosphorylation, suggesting the importance of the Daple/Dvl/CK1ε trimeric protein complex. We further found that Thr224 phosphorylation of Dvl was required for full activation of ß-catenin transcriptional activity. Consistent with this, wild-type Daple promoted ß-catenin transcriptional activity, following dissociation of ß-catenin and axin. Finally, Wnt3a stimulation increased the membrane localization of Daple and its association with Dvl, and Daple knockdown attenuated Wnt3a-mediated ß-catenin transcriptional activity. Collectively, these data suggested a essential role of spatial Daple localization in CK1ε-mediated activation of Dvl in the canonical Wnt signaling pathway.

Low fluid shear stress promoted ciliogenesis via Dvl2 in hUVECs.

This study aims to explore the mechanism of fluid shear stress in regulating the primary cilia assembly or disassembly in human umbilical vein endothelial cells (hUVECs) using microfluidic chamber experiments. Immunofluorescence analysis showed that primary cilia assembled under disturbed fluid shear stress (DF) of 1 dyne/cm2, while disassembled under unidirectional shear stress (USS) of 15 dynes/cm2. Disheveled (Dvl2) in Wnt signaling pathway was effectively co-immunoprecipitated with Bardet-Biedl syndrome proteins 8 (Bbs8) and γ-tubulin. Compared with those in the control group, the percentages of ciliated cells with Dvl2 overexpression were found to be 67% and 59.667%, respectively, under USS and DF (an increment of 21-38.7%); while, those with Dvl2 silencing were 16% and 32.667%, respectively, under USS and DF (a decrement of 23-30%). Further, the expression of Bbs8 and γ-tubulin was decreased by RNA interference of Dvl2 but increased with Dvl2 overexpression. The results indicated that Dvl2 played a pivotal role during DF-induced primary cilia assembly, and was important for apical docking of basal bodies through Bbs8 and γ-tubulin.