Cell Biology of Canonical Wnt Signaling

Colorectal cancer cells with stably expressed SIRT3 demonstrate proliferating retardation by Wnt/β-catenin cascade inactivation

Colorectal cancer (CRC) is a typical and lethal digestive system malignancy. In this study, we investigated the effect of sirtuin 3 (SIRT3) expression, a fidelity mitochondrial protein, on the proliferation of CRC cells and the mechanisms involved. Using the University of Alabama at Birmingham Cancer Data Analysis Portal database and the Clinical Proteomic Tumour Analysis Consortium database, we discovered that low expression of SIRT3 in CRC was a negative factor for survival prognosis (P < .05). Meanwhile, SIRT3 expression was correlated with distant metastasis and tumour, node, metastasis stage of CRC patients (P < .05). Subsequently, we observed that CRC cells with stable SIRT3 expression exhibited a significant decrease in proliferative capacities both in vitro and in vivo, compared to their counterparts (P < .05). Further investigation using western blot, immunoprecipitation and TOPflash/FOPflash assay showed the mechanism of growth retardation of these cells was highly associated with the degradation of β-catenin in cytosol, and the localization of β-catenin/α-catenin complex in the nucleus. In conclusion, our findings suggest that the inhibition of CRC cell proliferation by SIRT3 is closely associated with the inactivation of the Wnt/β-catenin signalling pathway.

Salidroside prevents gestational hypertension-induced impairment of offspring learning and memory via Wnt/Skp2 pathway

BACKGROUND

Salidroside (Sal) has been found to protect against multiple impairments caused by diabetes, and we designed this study to investigate the effect of Sal on gestational hypertension (GHP)-induced impairment of offspring learning and memory.

METHODS

We established a GHP rat model by intraperitoneal injection of NG-nitro-L-arginine methyl ester (L-NAME), and treated with Sal by daily gavage. We used Morris Water Maze test to evaluate the learning and memory ability of offspring rats. HE staining was used to measured the pathological changes in hippocampus of offspring. Immunohistochemistry, cellular immunofluorescence and western blot were used to detect the protein expression.

RESULTS

The learning and memory abilities of GHP offspring rats were significantly lower than those of normal rat offspring, while Sal treatment could significantly improve the learning and memory abilities of GHP offspring rats. HE staining did not reveal pathological differences in the hippocampus of normal rats, GHP rats and Sal-treated GHP offspring rats. However, Sal treatment can significantly increase the expression of Wnt1 and Skp2 protein, and decrease the expression of P27kiwf and P21waf1 protein in the hippocampus of GHP offspring rats. In vitro, Sal significantly promoted the proliferation and differentiation on neural stem cell, while Wnt1 knockdown could reverse these promotions by Sal. In the hippocampus of GHP offspring rats, Sal treatment significantly increased the expression of Tuj1, SOX2, Ki67 and DCX protein.

CONCLUSION

Salidroside significantly improves the learning and memory impairment of offspring caused by GHP, and its mechanism may be related to the fact that Salidroside promotes the proliferation and differentiation of neural stem cells by activating the Wnt1/Skp2 signaling pathway.

Regulation of YAP and Wnt signaling by the endosomal protein MAMDC4

Maintenance of the intestinal epithelium requires constant self-renewal and regeneration. Tight regulation of proliferation and differentiation of intestinal stem cells within the crypt region is critical to maintaining homeostasis. The transcriptional co-factors β-catenin and YAP are required for proliferation during normal homeostasis as well as intestinal regeneration after injury: aberrant signaling activity results in over proliferation and tumorigenesis. Although both YAP and β-catenin activity are controlled along canonical pathways, it is becoming increasingly clear that non-canonical regulation of these transcriptional regulators plays a role in fine tuning their activity. We have shown previously that MAMDC4 (Endotubin, AEGP), an integral membrane protein present in endosomes, regulates both YAP and β-catenin activity in kidney epithelial cells and in the developing intestinal epithelium. Here we show that MAMDC4 interacts with members of the signalosome and mediates cross-talk between YAP and β-catenin. Interestingly, this cross-talk occurs through a non-canonical pathway involving interactions between AMOT:YAP and AMOT:β-catenin.

Na,K-ATPase activity promotes macropinocytosis in colon cancer via Wnt signaling

Recent research has shown that membrane trafficking plays an important role in canonical Wnt signaling through sequestration of the β-catenin destruction complex inside multivesicular bodies (MVBs) and lysosomes. In this study, we introduce Ouabain, an inhibitor of the Na,K-ATPase pump that establishes electric potentials across membranes, as a potent inhibitor of Wnt signaling. We find that Na,K-ATPase levels are elevated in advanced colon carcinoma, that this enzyme is elevated in cancer cells with constitutively activated Wnt pathway and is activated by GSK3 inhibitors that increase macropinocytosis. Ouabain blocks macropinocytosis, which is an essential step in Wnt signaling, probably explaining the strong effects of Ouabain on this pathway. In Xenopus embryos, brief Ouabain treatment at the 32-cell stage, critical for the earliest Wnt signal in development-inhibited brains, could be reversed by treatment with Lithium chloride, a Wnt mimic. Inhibiting membrane trafficking may provide a way of targeting Wnt-driven cancers.

Inhibition of glycogen synthase kinase-3 enhances NRF2 protein stability, nuclear localisation and target gene transcription in pancreatic beta cells

Accumulation of reactive oxygen species (i.e., oxidative stress) is a leading cause of beta cell dysfunction and apoptosis in diabetes. NRF2 (NF-E2 p45-related factor-2) regulates the adaptation to oxidative stress, and its activity is negatively regulated by the redox-sensitive CUL3 (cullin-3) ubiquitin ligase substrate adaptor KEAP1 (Kelch-like ECH-associated protein-1). Additionally, NRF2 is repressed by the insulin-regulated Glycogen Synthase Kinase-3 (GSK3). We have demonstrated that phosphorylation of NRF2 by GSK3 enhances β-TrCP (beta-transducin repeat-containing protein) binding and ubiquitylation by CUL1 (cullin-1), resulting in increased proteasomal degradation of NRF2. Thus, we hypothesise that inhibition of GSK3 activity or β-TrCP binding upregulates NRF2 and so protects beta cells against oxidative stress. We have found that treating the pancreatic beta cell line INS-1 832/13 with the KEAP1 inhibitor TBE31 significantly enhanced NRF2 protein levels. The presence of the GSK3 inhibitor CT99021 or the β-TrCP-NRF2 protein-protein interaction inhibitor PHAR, along with TBE31, resulted in prolonged NRF2 stability and enhanced nuclear localisation (P < 0.05). TBE31-mediated induction of NRF2-target genes encoding NAD(P)H quinone oxidoreductase 1 (Nqo1), glutamate-cysteine ligase modifier (Gclm) subunit and heme oxygenase (Hmox1) was significantly enhanced by the presence of CT99021 or PHAR (P < 0.05) in both INS-1 832/13 and in isolated mouse islets. Identical results were obtained using structurally distinct GSK3 inhibitors and inhibition of KEAP1 with sulforaphane. In summary, we demonstrate that GSK3 and β-TrCP/CUL1 regulate the proteasomal degradation of NRF2, enhancing the impact of KEAP1 regulation, and so contributes to the redox status of pancreatic beta cells. Inhibition of GSK3, or β-TrCP/CUL1 binding to NRF2 may represent a strategy to protect beta cells from oxidative stress.

The interplay between Wnt signaling pathways and microtubule dynamics

Wnt signaling pathways represent an evolutionarily highly conserved, intricate network of molecular interactions that regulates various aspects of cellular behavior, including embryonic development and tissue homeostasis. Wnt signaling pathways share the β-catenin-dependent (canonical) and the multiple β-catenin-independent (non-canonical) pathways. These pathways collectively orchestrate a wide range of cellular processes through distinct mechanisms of action. Both the β-catenin-dependent and β-catenin-independent pathways are closely intertwined with microtubule dynamics, underscoring the complex crosstalk between Wnt signaling and the cellular cytoskeleton. This interplay involves several mechanisms, including how the components of Wnt signaling can influence the stability, organization, and distribution of microtubules. The modulation of microtubule dynamics by Wnt signaling plays a crucial role in coordinating cellular behaviors and responses to external signals. In this comprehensive review, we discussed the current understanding of how Wnt signaling and microtubule dynamics intersect in various aspects of cellular behavior. This study provides insights into our understanding of these crucial cellular processes.

Advancements in the Understanding of Small-Cell Neuroendocrine Cervical Cancer: Where We Stand and What Lies Ahead

Small-cell neuroendocrine cervical carcinoma (SCNCC) is a rare yet aggressive gynecological malignancy associated with dismal clinical outcomes. Its rarity has led to a limited number of retrospective studies and an absence of prospective research, posing significant challenges for evidence-based treatment approaches. As a result, most gynecologic oncology centers have limited experience with this tumor, emphasizing the urgent need for a comprehensive review and summary. This article systematically reviews the pathogenesis, immunohistochemical and molecular characteristics, prognostic factors, and clinical management of gynecologic SCNCC. We specifically focused on reviewing the distinct genomic characteristics of SCNCC identified via next-generation sequencing technologies, including loss of heterozygosity (LOH), somatic mutations, structural variations (SVs), and microRNA alterations. The identification of these actionable genomic events offers promise for discovering new molecular targets for drug development and enhancing therapeutic outcomes. Additionally, we delve deeper into key clinical challenges, such as determining the optimal treatment modality between chemoradiation and surgery for International Federation of Gynecology and Obstetrics (FIGO) stage I phase patients within a precision stratification framework, as well as the role of targeted therapy within the homologous recombination (HR) pathway, immune checkpoint inhibitors (ICIs), and prophylactic cranial irradiation (PCI) in the management of SCNCC. Finally, we anticipate the utilization of multiple SCNCC models, including cancer tissue-originated spheroid (CTOS) lines and patient-derived xenografts (PDXs), to decipher driver events and develop individualized therapeutic strategies for clinical application.

The oncogenic role and regulatory mechanism of ACAA2 in human ovarian cancer

Acetyl-CoAacyltransferase2 (ACAA2) is a key enzyme in the fatty acid oxidation pathway that catalyzes the final step of mitochondrial β oxidation, which plays an important role in fatty acid metabolism. The expression of ACAA2 is closely related to the occurrence and malignant progression of tumors. However, the function of ACAA2 in ovarian cancer is unclear. The expression level and prognostic value of ACAA2 were analyzed by databases. Gain and loss of function were carried out to explore the function of ACAA2 in ovarian cancer. RNA-seq and bioinformatics methods were applied to illustrate the regulatory mechanism of ACAA2. ACAA2 overexpression promoted the growth, proliferation, migration, and invasion of ovarian cancer, and ACAA2 knockdown inhibited the malignant progression of ovarian cancer as well as the ability of subcutaneous tumor formation in nude mice. At the same time, we found that OGT can induce glycosylation modification of ACAA2 and regulate the karyoplasmic distribution of ACAA2. OGT plays a vital role in ovarian cancer as a function of oncogenes. In addition, through RNA-seq sequencing, we found that ACAA2 regulates the expression of DIXDC1. ACAA2 regulated the malignant progression of ovarian cancer through the WNT/β-Catenin signaling pathway probably. ACAA2 is an oncogene in ovarian cancer and has the potential to be a target for ovarian cancer therapy.

Glioma Stem Cells-Features for New Therapy Design

On a molecular level, glioma is very diverse and presents a whole spectrum of specific genetic and epigenetic alterations. The tumors are unfortunately resistant to available therapies and the survival rate is low. The explanation of significant intra- and inter-tumor heterogeneity and the infiltrative capability of gliomas, as well as its resistance to therapy, recurrence and aggressive behavior, lies in a small subset of tumor-initiating cells that behave like stem cells and are known as glioma cancer stem cells (GCSCs). They are responsible for tumor plasticity and are influenced by genetic drivers. Additionally, GCSCs also display greater migratory abilities. A great effort is under way in order to find ways to eliminate or neutralize GCSCs. Many different treatment strategies are currently being explored, including modulation of the tumor microenvironment, posttranscriptional regulation, epigenetic modulation and immunotherapy.

Frizzled receptors (FZDs) in Wnt signaling: potential therapeutic targets for human cancers

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

Current perspectives on the multiple roles of osteoclasts: Mechanisms of osteoclast-osteoblast communication and potential clinical implications

Bone remodeling is a complex process involving the coordinated actions of osteoblasts and osteoclasts to maintain bone homeostasis. While the influence of osteoblasts on osteoclast differentiation is well established, the reciprocal regulation of osteoblasts by osteoclasts has long remained enigmatic. In the past few years, a fascinating new role for osteoclasts has been unveiled in promoting bone formation and facilitating osteoblast migration to the remodeling sites through a number of different mechanisms, including the release of factors from the bone matrix following bone resorption and direct cell-cell interactions. Additionally, considerable evidence has shown that osteoclasts can secrete coupling factors known as clastokines, emphasizing the crucial role of these cells in maintaining bone homeostasis. Due to their osteoprotective function, clastokines hold great promise as potential therapeutic targets for bone diseases. However, despite long-standing work to uncover new clastokines and their effect in vivo, more substantial efforts are still required to decipher the mechanisms and pathways behind their activity in order to translate them into therapies. This comprehensive review provides insights into our evolving understanding of the osteoclast function, highlights the significance of clastokines in bone remodeling, and explores their potential as treatments for bone diseases suggesting future directions for the field.

Dissection of N-deacetylase and N-sulfotransferase activities of NDST1 and their effects on Wnt8 distribution and signaling in Xenopus embryos

Wnt is a family of secreted signaling proteins involved in the regulation of cellular processes, including maintenance of stem cells, carcinogenesis, and cell differentiation. In the context of early vertebrate embryogenesis, graded distribution of Wnt proteins has been thought to regulate positional information along the antero-posterior axis. However, understanding of the molecular basis for Wnt spatial distribution remains poor. Modified states of heparan sulfate (HS) proteoglycans are essential for Wnt8 localization, because depletion of N-deacetylase/N-sulfotransferase 1 (NDST1), a modification enzyme of HS chains, decreases Wnt8 levels and NDST1 overexpression increases Wnt8 levels on the cell surface. Since overexpression of NDST1 increases both deacetylation and N-sulfation of HS chains, it is not clear which function of NDST1 is actually involved in Wnt8 localization. In the present study, we generated an NDST1 mutant that specifically increases deacetylation, but not N-sulfation, of HS chains in Xenopus embryos. Unlike wild-type NDST1, this mutant did not increase Wnt8 accumulation on the cell surface, but it reduced canonical Wnt signaling, as determined with the TOP-Flash reporter assay. These results suggest that N-sulfation of HS chains is responsible for localization of Wnt8 and Wnt8 signaling, whereas deacetylation has an inhibitory effect on canonical Wnt signaling. Consistently, overexpression of wild-type NDST1, but not the mutant, resulted in small eyes in Xenopus embryos. Thus, our NDST1 mutant enables us to dissect the regulation of Wnt8 localization and signaling by HS proteoglycans by specifically manipulating the enzymatic activities of NDST1.

ZNF554 Inhibits Endometrial Cancer Progression via Regulating RBM5 and Inactivating WNT/β-Catenin Signaling Pathway

OBJECTIVE

Uterine corpus endometrial carcinoma (UCEC), a kind of gynecologic malignancy, poses a significant risk to women's health. The precise mechanism underlying the development of UCEC remains elusive. Zinc finger protein 554 (ZNF554), a member of the Krüppel-associated box domain zinc finger protein superfamily, was reported to be dysregulated in various illnesses, including malignant tumors. This study aimed to examine the involvement of ZNF554 in the development of UCEC.

METHODS

The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot assay. Cells with stably overexpressed or knocked-down ZNF554 were established through lentivirus infection. CCK-8, wound healing, and Transwell invasion assays were employed to assess cell proliferation, migration, and invasion. Propidium iodide (PI) staining combined with fluorescence-activated cell sorting (FACS) flow cytometer was utilized to detect cell cycle distribution. qRT-PCR and Western blotting were conducted to examine relative mRNA and protein levels. Chromatin immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5 (RBM5).

RESULTS

The expression of ZNF554 was found to be reduced in both UCEC samples and cell lines. Decreased expression of ZNF554 was associated with higher tumor stage, decreased overall survival, and reduced disease-free survival in UCEC. ZNF554 overexpression suppressed cell proliferation, migration, and invasion, while also inducing cell cycle arrest. In contrast, a decrease in ZNF554 expression resulted in the opposite effect. Mechanistically, ZNF554 transcriptionally regulated RBM5, leading to the deactivation of the Wingless (WNT)/β-catenin signaling pathway. Moreover, the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression on β-catenin and p-glycogen synthase kinase-3β (p-GSK-3β). Similarly, the deliberate activation of RBM5 reduced the increase in β-catenin and p-GSK-3β caused by the suppression of ZNF554. In vitro experiments showed that ZNF554 overexpression-induced decreases in cell proliferation and migration were counteracted by RBM5 knockdown. Additionally, when RBM5 was overexpressed, it hindered the improvements in cell proliferation and migration caused by reducing the ZNF554 levels.

CONCLUSION

ZNF554 functions as a tumor suppressor in UCEC. Furthermore, ZNF554 regulates UCEC progression through the RBM5/WNT/β-catenin signaling pathway. ZNF554 shows a promise as both a prognostic biomarker and a therapeutic target for UCEC.

Research advances in Peyronie's disease: a comprehensive review on genomics, pathways, phenotypic manifestation, and therapeutic targets

INTRODUCTION

Penile induration disease, commonly known as Peyronie's disease (PD), is a connective tissue disorder that affects the penis, leading to the development of fibrous plaques, penile curvature, and erectile dysfunction. PD is a common male reproductive system disease with a complex etiology involving multiple genes, signaling pathways, and different phenotypes.

OBJECTIVES

The etiology and pathogenesis of PD remain poorly understood, hindering the development of effective treatment strategies. By understanding the underlying mechanisms of PD, we can pave the way for targeted therapies and improved patient outcomes.

METHODS

We reviewed the epidemiology and pathophysiology of PD. We performed database searches on Google Scholar, PubMed, Medline, and Web of Science from inception to September 2023. The literature reviewed included priapism guidelines, review articles, current trial studies, and various literature related to PD.

RESULTS

This article provides a comprehensive overview of the current research progress on the disease, focusing on its genetic factors, signaling pathways, cellular mechanisms, phenotypic manifestations, and therapeutic targets. It can help identify individuals at higher risk, aid in early detection and intervention, and provide insights into fibrosis and tissue remodeling. It can also reveal potential therapeutic targets, guide accurate diagnoses and treatment strategies, and address the impact of the disease on patients' quality of life.

CONCLUSION

By integrating insights from genomics, molecular pathways, clinical phenotypes, and therapeutic potentials, our research aims to achieve a deeper and more comprehensive understanding of PD, propelling the field toward innovative strategies that enhance the lives of those affected by PD. The complex manifestations and pathogenesis of PD necessitate the use of multiple treatment methods for personalized care.

Revealing mitf functions and visualizing allografted tumor metastasis in colorless and immunodeficient Xenopus tropicalis

Transparent immunodeficient animal models not only enhance in vivo imaging investigations of visceral organ development but also facilitate in vivo tracking of transplanted tumor cells. However, at present, transparent and immunodeficient animal models are confined to zebrafish, presenting substantial challenges for real-time, in vivo imaging studies addressing specific biological inquiries. Here, we employed a mitf-/-/prkdc-/-/il2rg-/- triple-knockout strategy to establish a colorless and immunodeficient amphibian model of Xenopus tropicalis. By disrupting the mitf gene, we observed the loss of melanophores, xanthophores, and granular glands in Xenopus tropicalis. Through the endogenous mitf promoter to drive BRAFV600E expression, we confirmed mitf expression in melanophores, xanthophores and granular glands. Moreover, the reconstruction of the disrupted site effectively reinstated melanophores, xanthophores, and granular glands, further highlighting the crucial role of mitf as a regulator in their development. By crossing mitf-/- frogs with prkdc-/-/il2rg-/- frogs, we generated a mitf-/-/prkdc-/-/il2rg-/- Xenopus tropicalis line, providing a colorless and immunodeficient amphibian model. Utilizing this model, we successfully observed intravital metastases of allotransplanted xanthophoromas and migrations of allotransplanted melanomas. Overall, colorless and immunodeficient Xenopus tropicalis holds great promise as a valuable platform for tumorous and developmental biology research.

The dual roles of circRNAs in Wnt/β-Catenin signaling and cancer progression

Cancer, a complex pathophysiological condition, arises from the abnormal proliferation and survival of cells due to genetic mutations. Dysregulation of cell cycle control, apoptosis, and genomic stability contribute to uncontrolled growth and metastasis. Tumor heterogeneity, microenvironmental influences, and immune evasion further complicate cancer dynamics. The intricate interplay between circular RNAs (circRNAs) and the Wnt/β-Catenin signalling pathway has emerged as a pivotal axis in the landscape of cancer biology. The Wnt/β-Catenin pathway, a critical regulator of cell fate and proliferation, is frequently dysregulated in various cancers. CircRNAs, a class of non-coding RNAs with closed-loop structures, have garnered increasing attention for their diverse regulatory functions. This review systematically explores the intricate crosstalk between circRNAs and the Wnt/β-Catenin pathway, shedding light on their collective impact on cancer initiation and progression. The review explores the diverse mechanisms through which circRNAs modulate the Wnt/β-Catenin pathway, including sponging microRNAs, interacting with RNA-binding proteins, and influencing the expression of key components in the pathway. Furthermore, the review highlights specific circRNAs implicated in various cancer types, elucidating their roles as either oncogenic or tumour-suppressive players in the context of Wnt/β-Catenin signaling. The intricate regulatory networks formed by circRNAs in conjunction with the Wnt/β-Catenin pathway are discussed, providing insights into potential therapeutic targets and diagnostic biomarkers. This comprehensive review delves into the multifaceted roles of circRNAs in orchestrating tumorigenesis through their regulatory influence on the Wnt/β-Catenin pathway.

Pinoresinol diglucoside mitigates dexamethasone-induced osteoporosis and chondrodysplasia in zebrafish

BACKGROUND

The global increase in the aging population has led to a higher incidence of osteoporosis among the elderly.

OBJECTIVE

This study aimed to evaluate the protective properties of pinoresinol diglucoside (PDG), an active constituent of Eucommia ulmoides, against dexamethasone-induced osteoporosis and chondrodysplasia.

METHODS

A zebrafish model of osteoporosis was established by exposing larval zebrafish to dexamethasone. The impact of PDG on bone mineralization was assessed through alizarin red and calcein staining. Alkaline phosphatase activity was quantified to evaluate osteoblast function. The influence of PDG on chondrogenesis was estimated using alcian blue staining. Fluorescence imaging and motor behavior analysis were employed to assess the protective effect of PDG on the structure and function of dexamethasone-induced skeletal teratogenesis. qPCR determined the expression of osteogenesis and Wnt signaling-related genes. Molecular docking was used to assess the potential interactions between PDG and Wnt receptors.

RESULTS

PDG significantly increased bone mineralization and corrected spinal curvature and cartilage malformations in the zebrafish model. Furthermore, PDG enhanced swimming abilities compared to the model group. PDG mitigated dexamethasone-induced skeletal abnormalities in zebrafish by upregulating Wnt signaling, showing potential interaction with Wnt receptors FZD2 and FZD5.

CONCLUSION

PDG mitigates dexamethasone-induced osteoporosis and chondrodysplasia by promoting bone formation and activating Wnt signaling.

Fucoidan suppresses proliferation and epithelial-mesenchymal transition process via Wnt/β-catenin signalling in hemangioma

Hemangioma is a common benign tumour that usually occurs on the skin of the head and neck, particularly among infants. The current clinical treatment against hemangioma is surgery excision, however, application of drug is a safer and more economical therapy for children suffering from hemangioma. As a natural sulfated polysaccharide rich in brown algae, fucoidan is widely recognized for anti-tumour bioactivity and dosage safety in humans. This study aims to demonstrate the anti-tumour effect and underlying mechanism of fucoidan against hemangioma in vivo and in vitro. We investigated the effects of fucoidan by culturing hemangioma cells in vitro and treating BALB/c mice bearing with hemangioma. At first, we measured the cell proliferation and migration ability through in vitro experiments. Then, we tested the expression of epithelial-mesenchymal transition (EMT) and Wnt/β-catenin pathway-related biomarkers by western blot and qPCR. Furthermore, we applied β-catenin-specific inhibitor, XAV939, to determine whether fucoidan suppressed EMT via the Wnt/β-catenin pathway in hemangioma cells. In vivo experiments, we applied oral gavage of fucoidan to treat EOMA-bearing mice, along with evaluating the safety and efficacy of fucoidan. We found that fucoidan remarkably inhibits the proliferation and EMT ability of hemangioma cells, which is dependent on the Wnt/β-catenin pathway. These results suggest that fucoidan exhibits tumour inhibitory effect on aggressive hemangioma via regulating the Wnt/β-catenin signalling pathway both in vitro and in vivo, providing a new potent drug candidate for treating hemangioma.

NEK2 plays an essential role in porcine embryonic development by maintaining mitotic division and DNA damage response via the Wnt/β-catenin signalling pathway

NIMA-related kinase 2 (NEK2) is a serine/threonine protein kinase that regulates mitosis and plays pivotal roles in cell cycle regulation and DNA damage repair. However, its function in porcine embryonic development is unknown. In this study, we used an NEK2-specific inhibitor, JH295 (JH), to investigate the role of NEK2 in embryonic development and the underlying regulatory mechanisms. Inhibition of NEK2 after parthenogenesis activation or in vitro fertilization significantly reduced the rates of cleavage and blastocyst formation, the numbers of trophectoderm and total cells and the cellular survival rate compared with the control condition. NEK2 inhibition delayed cell cycle progression at all stages from interphase to cytokinesis during the first mitotic division; it caused abnormal nuclear morphology in two- and four-cell stage embryos. Additionally, NEK2 inhibition significantly increased DNA damage and apoptosis, and it altered the expression levels of DNA damage repair- and apoptosis-related genes. Intriguingly, NEK2 inhibition downregulated the expression of β-catenin and its downstream target genes. To validate the relationship between Wnt/β-catenin signalling and NEK2 during porcine embryonic development, we cultured porcine embryos in JH-treated medium with or without CHIR99021, a Wnt activator. CHIR99021 co-treatment strongly restored the developmental parameters reduced by NEK2 inhibition to control levels. Our findings suggest that NEK2 plays an essential role in porcine embryonic development by regulating DNA damage repair and normal mitotic division via the Wnt/β-catenin signalling pathway.

The origin and evolution of Wnt signalling

The Wnt signal transduction pathway has essential roles in the formation of the primary body axis during development, cellular differentiation and tissue homeostasis. This animal-specific pathway has been studied extensively in contexts ranging from developmental biology to medicine for more than 40 years. Despite its physiological importance, an understanding of the evolutionary origin and primary function of Wnt signalling has begun to emerge only recently. Recent studies on very basal metazoan species have shown high levels of conservation of components of both canonical and non-canonical Wnt signalling pathways. Furthermore, some pathway proteins have been described also in non-animal species, suggesting that recruitment and functional adaptation of these factors has occurred in metazoans. In this Review, we summarize the current state of research regarding the evolutionary origin of Wnt signalling, its ancestral function and the characteristics of the primal Wnt ligand, with emphasis on the importance of genomic studies in various pre-metazoan and basal metazoan species.

Targeting glycogen synthase kinase-3β for Alzheimer's disease: Recent advances and future Prospects

Senile plaques induced by β-amyloid (Aβ) abnormal aggregation and neurofibrillary tangles (NFT) caused by tau hyperphosphorylation are important pathological manifestations of Alzheimer's disease (AD). Glycogen synthase kinase-3 (GSK-3) is a conserved kinase; one member GSK-3β is highly expressed in the AD brain and involved in the formation of NFT. Hence, pharmacologically inhibiting GSK-3β activity and expression is a good approach to treat AD. As summarized in this article, multiple GSK-3β inhibitors has been comprehensively summarized over recent five years. However, only lithium carbonate and Tideglusib have been studied in clinical trials of AD. Besides ATP-competitive and non-ATP-competitive inhibitors, peptide inhibitors, allosteric inhibitors and other types of inhibitors have gradually attracted more interest. Moreover, considering the close relationship between GSK-3β and other targets involved in cholinergic hypothesis, Aβ aggregation hypothesis, tau hyperphosphorylation hypothesis, oxidative stress hypothesis, neuro-inflammation hypothesis, etc., diverse multifunctional molecules and multi-target directed ligands (MTDLs) have also been disclosed. We hope that these recent advances and critical perspectives will facilitate the discovery of safe and effective GSK-3β inhibitors for AD treatment.

Strategies to decrease inequalities in cancer therapeutics, care and prevention: Proceedings on a conference organized by the Pontifical Academy of Sciences and the European Academy of Cancer Sciences, Vatican City, February 23-24, 2023

Analyses of inequalities related to prevention and cancer therapeutics/care show disparities between countries with different economic standing, and within countries with high Gross Domestic Product. The development of basic technological and biological research provides clinical and prevention opportunities that make their implementation into healthcare systems more complex, mainly due to the growth of Personalized/Precision Cancer Medicine (PCM). Initiatives like the USA-Cancer Moonshot and the EU-Mission on Cancer and Europe's Beating Cancer Plan are initiated to boost cancer prevention and therapeutics/care innovation and to mitigate present inequalities. The conference organized by the Pontifical Academy of Sciences in collaboration with the European Academy of Cancer Sciences discussed the inequality problem, dependent on the economic status of a country, the increasing demands for infrastructure supportive of innovative research and its implementation in healthcare and prevention programs. Establishing translational research defined as a coherent cancer research continuum is still a challenge. Research has to cover the entire continuum from basic to outcomes research for clinical and prevention modalities. Comprehensive Cancer Centres (CCCs) are of critical importance for integrating research innovations to preclinical and clinical research, as for ensuring state-of-the-art patient care within healthcare systems. International collaborative networks between CCCs are necessary to reach the critical mass of infrastructures and patients for PCM research, and for introducing prevention modalities and new treatments effectively. Outcomes and health economics research are required to assess the cost-effectiveness of new interventions, currently a missing element in the research portfolio. Data sharing and critical mass are essential for innovative research to develop PCM. Despite advances in cancer research, cancer incidence and prevalence is growing. Making cancer research infrastructures accessible for all patients, considering the increasing inequalities, requires science policy actions incentivizing research aimed at prevention and cancer therapeutics/care with an increased focus on patients' needs and cost-effective healthcare.

WNT7A promotes tumorigenesis of head and neck squamous cell carcinoma via activating FZD7/JAK1/STAT3 signaling

Wnt signaling are critical pathway involved in organ development, tumorigenesis, and cancer progression. WNT7A, a member of the Wnt family, remains poorly understood in terms of its role and the underlying molecular mechanisms it entails in head and neck squamous cell carcinoma (HNSCC). According to the Cancer Genome Atlas (TCGA), transcriptome sequencing data of HNSCC, the expression level of WNT7A in tumors was found to be higher than in adjacent normal tissues, which was validated using Real-time RT-PCR and immunohistochemistry. Unexpectedly, overexpression of WNT7A did not activate the canonical Wnt-β-catenin pathway in HNSCC. Instead, our findings suggested that WNT7A potentially activated the FZD7/JAK1/STAT3 signaling pathway, leading to enhanced cell proliferation, self-renewal, and resistance to apoptosis. Furthermore, in a patient-derived xenograft (PDX) tumor model, high expression of WNT7A and phosphorylated STAT3 was observed, which positively correlated with tumor progression. These findings underscore the significance of WNT7A in HNSCC progression and propose the targeting of key molecules within the FZD7/JAK1/STAT3 pathway as a promising strategy for precise treatment of HNSCC.

Wnt signaling in cell adhesion, development, and colon cancer

Wnt signaling is essential for embryonic development, influencing processes such as axis formation, cell proliferation and differentiation, cell fate decisions, and axon guidance. It also plays a role in maintaining tissue homeostasis in adult organisms. The loss of normal cell polarity and adhesion caused by Wnt signaling activation is a fundamental step for tumor progression and metastasis. Activating the canonical Wnt pathway is a driving force in many human cancers, especially colorectal, hepatocellular, and mammary carcinomas. Wnt causes the stabilization and nuclear transport of newly synthesized transcriptional regulator β-catenin. The generally accepted view is that the canonical effects of Wnt growth factors are caused by the transcription of β-catenin target genes. Here, we review recent findings that indicate Wnt is a regulator of many other cellular physiological activities, such as macropinocytosis, endosome trafficking, protein stability, focal adhesions, and lysosomal activity. Some of these regulatory responses occur within minutes and do not require new protein synthesis, indicating that there is much more to Wnt beyond the well-established transcriptional role of β-catenin. The main conclusion that emerges from these studies is that in basal cell conditions, the activity of the key protein kinase GSK3, which is inhibited by Wnt pathway activation, normally represses the actin machinery that orchestrates macropinocytosis with implications in cancer. These contributions expand our understanding of the multifaceted roles of Wnt signaling in cellular processes, development, and cancer, providing insights into potential therapeutic targets and strategies.

HPV E6/E7: insights into their regulatory role and mechanism in signaling pathways in HPV-associated tumor

Human papillomavirus (HPV) is a class of envelope-free double-stranded DNA virus. HPV infection has been strongly associated with the development of many malignancies, such as cervical, anal and oral cancers. The viral oncoproteins E6 and E7 perform central roles on HPV-induced carcinogenic processes. During tumor development, it usually goes along with the activation of abnormal signaling pathways. E6 and E7 induces changes in cell cycle, proliferation, invasion, metastasis and other biological behaviors by affecting downstream tumor-related signaling pathways, thus promoting malignant transformation of cells and ultimately leading to tumorigenesis and progression. Here, we summarized that E6 and E7 proteins promote HPV-associated tumorigenesis and development by regulating the activation of various tumor-related signaling pathways, for example, the Wnt/β-catenin, PI3K/Akt, and NF-kB signaling pathway. We also discussed the importance of HPV-encoded E6 and E7 and their regulated tumor-related signaling pathways for the diagnosis and effective treatment of HPV-associated tumors.

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

A review of Glycogen Synthase Kinase-3 (GSK3) inhibitors for cancers therapies

The intricate molecular pathways governing cancer development and progression have spurred intensive investigations into novel therapeutic targets. Glycogen Synthase Kinase-3 (GSK3), a complex serine/threonine kinase, has emerged as a key player with intricate roles in various cellular processes, including cell proliferation, differentiation, apoptosis, and metabolism. Harnessing GSK3 inhibitors as potential candidates for cancer therapy has garnered significant interest due to their ability to modulate key signalling pathways that drive oncogenesis. The review encompasses a thorough examination of the molecular mechanisms underlying GSK3's involvement in cancer progression, shedding light on its interaction with critical pathways such as Wnt/β-catenin, PI3K/AKT, and NF-κB. Through these interactions, GSK3 exerts influence over tumour growth, invasion, angiogenesis, and metastasis, rendering it an attractive target for therapeutic intervention. The discussion includes preclinical and clinical studies, showcasing the inhibitors efficacy across a spectrum of cancer types, including pancreatic, ovarian, lung, and other malignancies. Insights from recent studies highlight the potential synergistic effects of combining GSK3 inhibitors with conventional chemotherapeutic agents or targeted therapies, opening avenues for innovative combinatorial approaches. This review provides a comprehensive overview of the current state of research surrounding GSK3 inhibitors as promising agents for cancer treatment.

Wnt/β-catenin signaling activation promotes lipogenesis in the steatotic liver via physical mTOR interaction

Background and aims

Wnt/β-catenin signaling plays an important role in regulating hepatic metabolism. This study is to explore the molecular mechanisms underlying the potential crosstalk between Wnt/β-catenin and mTOR signaling in hepatic steatosis.

Methods

Transgenic mice (overexpress Wnt1 in hepatocytes, Wnt+) mice and wild-type littermates were given high fat diet (HFD) for 12 weeks to induce hepatic steatosis. Mouse hepatocytes cells (AML12) and those transfected to cause constitutive β-catenin stabilization (S33Y) were treated with oleic acid for lipid accumulation.

Results

Wnt+ mice developed more hepatic steatosis in response to HFD. Immunoblot shows a significant increase in the expression of fatty acid synthesis-related genes (SREBP-1 and its downstream targets ACC, AceCS1, and FASN) and a decrease in fatty acid oxidation gene (MCAD) in Wnt+ mice livers under HFD. Wnt+ mice also revealed increased Akt signaling and its downstream target gene mTOR in response to HFD. In vitro, increased lipid accumulation was detected in S33Y cells in response to oleic acid compared to AML12 cells reinforcing the in vivo findings. mTOR inhibition by rapamycin led to a down-regulation of fatty acid synthesis in S33Y cells. In addition, β-catenin has a physical interaction with mTOR as verified by co-immunoprecipitation in hepatocytes.

Conclusions

Taken together, our results demonstrate that β-catenin stabilization through Wnt signaling serves a central role in lipid metabolism in the steatotic liver through up-regulation of fatty acid synthesis via Akt/mTOR signaling. These findings suggest hepatic Wnt signaling may represent a therapeutic strategy in hepatic steatosis.

Biomimetic Fibers Based on Equidistant Micropillar Arrays Determines Chondrocyte Fate via Mechanoadaptability

It is recognized that the changes in the physical properties of extracellular matrix (ECM) result in fine-tuned cell responses including cell morphology, proliferation and differentiation. In this study, a novel patterned equidistant micropillar substrate based on polydimethylsiloxane (PDMS) is designed to mimic the collagen fiber-like network of the cartilage matrix. By changing the component of the curing agent to an oligomeric base, micropillar substrates with the same topology but different stiffnesses are obtained and it is found that chondrocytes seeded onto the soft micropillar substrate maintain their phenotype by gathering type II collagen and aggrecan more effectively than those seeded onto the stiff micropillar substrate. Moreover, chondrocytes sense and respond to micropillar substrates with different stiffnesses by altering the ECM-cytoskeleton-focal adhesion axis. Further, it is found that the soft substrate-preserved chondrocyte phenotype is dependent on the activation of Wnt/β-catenin signaling. Finally, it is indicated that the changes in osteoid-like region formation and cartilage phenotype loss in the stiffened sclerotic area of osteoarthritis cartilage to validate the changes triggered by micropillar substrates with different stiffnesses. This study provides the cell behavior changes that are more similar to those of real chondrocytes at tissue level during the transition from a normal state to a state of osteoarthritis.

New insights into glycogen synthase kinase-3: A common target for neurodegenerative diseases

Glycogen synthase kinase 3 (GSK-3) is a highly conserved protein serine/threonine kinase that plays a central role in a wide variety of cellular processes to coordinate catabolic and anabolic pathways and regulate cell growth and fate. There is increasing evidence showing that abnormal glycogen synthase kinase 3 (GSK-3) is associated with the pathogenesis and progression of many disorders, such as cancer, diabetes, psychiatric diseases, and neurodegenerative diseases. In this review, we summarize recent findings about the regulatory role of GSK-3 in the occurrence and development of multiple neurodegenerative diseases, mainly focusing on Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. The aim of this study is to provide new insight into the shared working mechanism of GSK-3 as a therapeutic target of multiple neurodegenerative diseases.

Intestinal Paneth cell differentiation relies on asymmetric regulation of Wnt signaling by Daam1/2

The mammalian intestine is one of the most rapidly self-renewing tissues, driven by stem cells residing at the crypt bottom. Paneth cells form a major element of the niche microenvironment providing various growth factors to orchestrate intestinal stem cell homeostasis, such as Wnt3. Different Wnt ligands can selectively activate β-catenin-dependent (canonical) or -independent (noncanonical) signaling. Here, we report that the Dishevelled-associated activator of morphogenesis 1 (Daam1) and its paralogue Daam2 asymmetrically regulate canonical and noncanonical Wnt (Wnt/PCP) signaling. Daam1/2 interacts with the Wnt inhibitor RNF43, and Daam1/2 double knockout stimulates canonical Wnt signaling by preventing RNF43-dependent degradation of the Wnt receptor, Frizzled (Fzd). Single-cell RNA sequencing analysis revealed that Paneth cell differentiation is impaired by Daam1/2 depletion because of defective Wnt/PCP signaling. Together, we identified Daam1/2 as an unexpected hub molecule coordinating both canonical and noncanonical Wnt, which is fundamental for specifying an adequate number of Paneth cells.

All the might of the osteocyte: emerging roles in chronic kidney disease

Osteocytes are the most abundant type of bone cell and play crucial roles in bone health. Osteocytes sense mechanical stress and orchestrate osteoblasts and osteoclasts to maintain bone density and strength. Beyond this, osteocytes have also emerged as key regulators of organ crosstalk, and they function as endocrine organs via their roles in secreting factors that mediate signaling within their neighboring bone cells and in distant tissues. As such, osteocyte dysfunction has been associated with the bone abnormalities seen across a spectrum of chronic kidney disease. Specifically, dysregulated osteocyte morphology and signaling have been observed in the earliest stages of chronic kidney disease and have been suggested to contribute to kidney disease progression. More important, US Food and Drug Administration-approved inhibitors of osteocytic secreted proteins, such as fibroblast growth factor 23 and sclerostin, have been used to treat bone diseases. The present mini review highlights new research that links dysfunctional osteocytes to the pathogenesis of chronic kidney disease mineral and bone disorder.

The PMA phorbol ester tumor promoter increases canonical Wnt signaling via macropinocytosis

Activation of the Wnt pathway lies at the core of many human cancers. Wnt and macropinocytosis are often active in the same processes, and understanding how Wnt signaling and membrane trafficking cooperate should improve our understanding of embryonic development and cancer. Here, we show that a macropinocytosis activator, the tumor promoter phorbol 12-myristate 13-acetate (PMA), enhances Wnt signaling. Experiments using the Xenopus embryo as an in vivo model showed marked cooperation between the PMA phorbol ester and Wnt signaling, which was blocked by inhibitors of macropinocytosis, Rac1 activity, and lysosome acidification. Human colorectal cancer tissue arrays and xenografts in mice showed a correlation of cancer progression with increased macropinocytosis/multivesicular body/lysosome markers and decreased GSK3 levels. The crosstalk between canonical Wnt, focal adhesions, lysosomes, and macropinocytosis suggests possible therapeutic targets for cancer progression in Wnt-driven cancers.

GSK3 as a Master Regulator of Cellular Processes

Since its initial purification and characterization as an enzyme negatively regulating glycogen synthase activity [...].

Addition of exogenous diacylglycerol enhances Wnt/β-catenin signaling through stimulation of macropinocytosis

Activation of Wnt signaling triggers macropinocytosis and drives many tumors. We now report that the exogenous addition of the second messenger lipid sn-1,2 DAG to the culture medium rapidly induces macropinocytosis. This is accompanied by potentiation of the effects of added Wnt3a recombinant protein or the glycogen synthase kinase 3 (GSK3) inhibitor lithium chloride (LiCl, which mimics Wnt signaling) in luciferase transcriptional reporter assays. In a colorectal carcinoma cell line in which mutation of adenomatous polyposis coli (APC) causes constitutive Wnt signaling, DAG addition increased levels of nuclear β-catenin, and this increase was partially inhibited by an inhibitor of macropinocytosis. DAG also expanded multivesicular bodies marked by the tetraspan protein CD63. In an in vivo situation, microinjection of DAG induced Wnt-like twinned body axes when co-injected with small amounts of LiCl into Xenopus embryos. These results suggest that the DAG second messenger plays a role in Wnt-driven cancer progression.

The Wnt/β-catenin signaling pathway inhibits osteoporosis by regulating the expression of TERT: an in vivo and in vitro study

Our study was performed to investigate whether the Wingless and int-1 (Wnt) signaling pathway promotes osteogenic differentiation and inhibits apoptosis in bone marrow mesenchymal stem cells (BMSCs) by regulating telomerase reverse transcriptase (TERT) expression. An in vivo model of osteoporosis (OP) in C57BL/6J mice by bilateral ovariectomy (OVX) and an in vitro model of H2O2-induced BMSCs were established separately. Western blotting was used to detect the expression of the pathway-related proteins TERT, β-catenin, and phosphorylated-glycogen synthase kinase-3beta (p-GSK3β)/GSK3β, the osteogenic-related markers osteopontin (OPN), bone morphogenetic protein 2 (BMP2), and runt-related transcription factor 2 (Runx2), and the apoptosis-related indicators B-cell lymphoma-2 (Bcl-2) and BAX. Osteoblastic phenotypes were also evaluated by alkaline phosphatase (ALP) staining and serum ALP activity assays. Osteogenic differentiation phenotypes in mice were verified by H&E staining, micro-CT, and parameter analysis of the femur. Western blotting results showed that the expression of the pathway-related proteins TERT, β-catenin, p-GSK3β/GSK3β was reduced in OVX mice and H2O2-induced BMSCs, accompanied by downregulated protein expression of osteogenic-related markers and antiapoptotic indicators and upregulated protein expression of apoptotic proteins compared to those in the control group. Mechanistic studies showed that the activation of Wnt signaling pathway in BMSCs promoted β-catenin translocation to the nucleus, as verified by immunofluorescence and facilitated colocalization between β-catenin and TERT, as verified by double-labeling immunofluorescence, thereby promoting osteogenic differentiation and reducing apoptosis. In summary, our experiments confirmed that the GSK3β/β-catenin/TERT pathway could regulate the osteogenic differentiation and apoptosis of BMSCs and that TERT might be a promising target for the future treatment of osteoporosis.

The WNT/β-catenin system in chronic kidney disease-mineral bone disorder syndrome

BACKGROUND

The WNT/β-catenin system is an evolutionarily conserved signaling pathway that plays a crucial role in morphogenesis and cell tissue formation during embryogenesis. Although usually suppressed in adulthood, it can be reactivated during organ damage and regeneration. Transient activation of the WNT/β-catenin pathway stimulates tissue regeneration after acute kidney injury, while persistent (uncontrolled) activation can promote the development of chronic kidney disease (CKD). CKD-MBD is a clinical syndrome that develops with systemic mineral and bone metabolism disorders caused by CKD, characterized by abnormal bone mineral metabolism and/or extraosseous calcification, as well as cardiovascular disease associated with CKD, including vascular stiffness and calcification.

OBJECTIVE

This paper aims to comprehensively review the WNT/β-catenin signaling pathway in relation to CKD-MBD, focusing on its components, regulatory molecules, and regulatory mechanisms. Additionally, this review highlights the challenges and opportunities for using small molecular compounds to target the WNT/β-catenin signaling pathway in CKD-MBD therapy.

METHODS

We conducted a comprehensive literature review using various scientific databases, including PubMed, Scopus, and Web of Science, to identify relevant articles. We searched for articles that discussed the WNT/β-catenin signaling pathway, CKD-MBD, and their relationship. We also reviewed articles that discussed the components of the WNT/β-catenin signaling pathway, its regulatory molecules, and regulatory mechanisms.

RESULTS

The WNT/β-catenin signaling pathway plays a crucial role in CKD-MBD by promoting vascular calcification and bone mineral metabolism disorders. The pathway's components include WNT ligands, Frizzled receptors, and LRP5/6 co-receptors, which initiate downstream signaling cascades leading to the activation of β-catenin. Several regulatory molecules, including GSK-3β, APC, and Axin, modulate β-catenin activation. The WNT/β-catenin signaling pathway also interacts with other signaling pathways, such as the BMP pathway, to regulate CKD-MBD.

CONCLUSIONS

The WNT/β-catenin signaling pathway is a potential therapeutic target for CKD-MBD. Small molecular compounds that target the components or regulatory molecules of the pathway may provide a promising approach to treat CKD-MBD. However, more research is needed to identify safe and effective compounds and to determine the optimal dosages and treatment regimens.

MiRNAs regulate cell communication in osteogenesis-angiogenesis coupling during bone regeneration

Bone regeneration is a complex process that requires not only the participation of multiple cell types, but also signal communication between cells. The two basic processes of osteogenesis and angiogenesis are closely related to bone regeneration and bone homeostasis. H-type vessels are a subtype of bone vessels characterized by high expression of CD31 and EMCN. These vessels play a key role in the regulation of bone regeneration and are important mediators of coupling between osteogenesis and angiogenesis. Molecular regulation between different cell types is important for coordination of osteogenesis and angiogenesis that promotes bone regeneration. MiRNAs are small non-coding RNAs that predominantly regulate gene expression at the post-transcriptional level and are closely related to cell communication. Specifically, miRNAs transduce external stimuli through various cell signaling pathways and cause a series of physiological and pathological effects. They are also deeply involved in the bone repair process. This review focuses on three signaling pathways related to osteogenesis-angiogenesis coupling, as well as the miRNAs involved in these pathways. Elucidation of the molecular mechanisms governing osteogenesis and angiogenesis is of great significance for bone regeneration.

From molecular basis to clinical insights: a challenging future for the vitamin D endocrine system in colorectal cancer

Colorectal cancer (CRC) is one of the most life-threatening neoplasias in terms of incidence and mortality worldwide. Vitamin D deficiency has been associated with an increased risk of CRC. 1α,25-Dihydroxyvitamin D3 [1,25(OH)2 D3 ], the most active vitamin D metabolite, is a pleiotropic hormone that, through its binding to a transcription factor of the nuclear receptor superfamily, is a major regulator of the human genome. 1,25(OH)2 D3 acts on colon carcinoma and stromal cells and displays tumor protective actions. Here, we review the variety of molecular mechanisms underlying the effects of 1,25(OH)2 D3 in CRC, which affect multiple processes that are dysregulated during tumor initiation and progression. Additionally, we discuss the epidemiological data that associate vitamin D deficiency and CRC, and the most relevant randomized controlled trials of vitamin D3 supplementation conducted in both healthy individuals and CRC patients.

Vitamin B6 is governed by the local compartmentalization of metabolic enzymes during growth

Vitamin B6 is a vital micronutrient across cell types and tissues, and dysregulated B6 levels contribute to human disease. Despite its importance, how B6 vitamer levels are regulated is not well understood. Here, we provide evidence that B6 dynamics are rapidly tuned by precise compartmentation of pyridoxal kinase (PDXK), the rate-limiting B6 enzyme. We show that canonical Wnt rapidly led to the accumulation of inactive B6 by shunting cytosolic PDXK into lysosomes. PDXK was modified with methyl-arginine Degron (MrDegron), a protein tag for lysosomes, which enabled delivery via microautophagy. Hyperactive lysosomes resulted in the continuous degradation of PDXK and B6 deficiency that promoted proliferation in Wnt-driven colorectal cancer (CRC) cells. Pharmacological or genetic disruption of the coordinated MrDegron proteolytic pathway was sufficient to reduce CRC survival in cells and organoid models. In sum, this work contributes to the repertoire of micronutrient-regulated processes that enable cancer cell growth and provides insight into the functional impact of B6 deficiencies for survival.

The PMA Phorbol Ester Tumor Promoter Increases Canonical Wnt Signaling Via Macropinocytosis

Activation of the Wnt pathway lies at the core of many human cancers. Wnt and macropinocytosis are often active in the same processes, and understanding how Wnt signaling and membrane trafficking cooperate should improve our understanding of embryonic development and cancer. Here we show that a macropinocytosis activator, the tumor promoter Phorbol 12-myristate 13-acetate (PMA), enhances Wnt signaling. Experiments using the Xenopus embryo as an in vivo model showed marked cooperation between the PMA phorbol ester and Wnt signaling, which was blocked by inhibitors of macropinocytosis, Rac1 activity, and lysosome acidification. Human colorectal cancer tissue arrays and xenografts in mice showed a correlation of cancer progression with increased macropinocytosis/multivesicular body/lysosome markers and decreased GSK3 levels. The crosstalk between canonical Wnt, focal adhesions, lysosomes, and macropinocytosis suggests possible therapeutic targets for cancer progression in Wnt-driven cancers.

CD44 expression is correlated with osteosarcoma cell progression and immune infiltration and affects the Wnt/β-catenin signaling pathway

CD44 is associated with a variety of human diseases and plays a potential role in tumorigenesis, however, the mechanism of its role in osteosarcoma remains unclear. We analyzed the expression of CD44 in the Cancer Genome Atlas (TCGA) and genotype-tissue expression pan-cancer data and found that it was highly expressed in most tumors, including sarcoma. The expression of CD44 in osteosarcoma cell lines was higher than that in human osteoblast cell line in the results of the Western blot and Immunohistochemical staining assay. The results of colony formation assay and CCK 8 showed that CD44 improved the proliferation capacity of osteosarcoma cells, transwell assay and wound healing assay showed that CD44 improved the migration capacity of osteosarcoma cells. Further studies revealed that CD44 exerts its influence on the biological behavior of osteosarcoma cells through the Wnt/β-catenin signaling pathway. Since CD44 may be involved in the immune response, we analyzed the correlation between CD44 expression and immune cell infiltration in TCGA database using the previous cluster analyzer R software package, TIMER2.0 database and, GEPIA2 database, and found its involvement in the immune infiltration of osteosarcoma. Therefore, we believe that CD44 could be a potential target for the treatment of osteosarcoma patients and may be a candidate biomarker for immune infiltration-related prognosis.

Devo-Aging: Intersections Between Development and Aging

There are two fundamental questions in developmental biology. How does a single fertilized cell give rise to a whole body? and how does this body later produce progeny? Synchronization of these embryonic and postembryonic developments ensures continuity of life from one generation to the next. An enormous amount of work has been done to unravel the molecular mechanisms behind these processes, but more recently, modern developmental biology has been expanded to study development in wider contexts, including regeneration, environment, disease, and even aging. However, we have just started to understand how the mechanisms that govern development also regulate aging. This review discusses examples of signaling pathways involved in development to elucidate how their regulation influences healthspan and lifespan. Therefore, a better knowledge of developmental signaling pathways stresses the possibility of using them as innovative biomarkers and targets for aging and age-related diseases.

Wnt3a-Loaded Extracellular Vesicles Promote Alveolar Epithelial Regeneration after Lung Injury

Compromised regeneration resulting from the deactivation of Wnt/β-catenin signaling contributes to the progression of chronic obstructive pulmonary disease (COPD) with limited therapeutic options. Extracellular cytokine-induced Wnt-based signaling provides an alternative option for COPD treatment. However, the hydrophobic nature of Wnt proteins limits their purification and use. This study devises a strategy to deliver the membrane-bound wingless-type MMTV integration site family, member 3A (Wnt3a) over a long distance by anchoring it to the surface of extracellular vesicles (EVs). The newly engineered Wnt3aWG EVs are generated by co-expressing Wnt3a with two genes encoding the membrane protein, WLS, and an engineered glypican, GPC6ΔGPI -C1C2. The bioactivity of Wnt3aWG EVs is validated using a TOPFlash assay and a mesoderm differentiation model of human pluripotent stem cells. Wnt3aWG EVs activate Wnt signaling and promote cell growth following human alveolar epithelial cell injury. In an elastase-induced emphysema model, impaired pulmonary function and enlarged airspace are greatly restored by the intravenous delivery of Wnt3aWG EVs. Single-cell RNA sequencing-based analyses further highlight that Wnt3aWG EV-activated regenerative programs are responsible for its beneficial effects. These findings suggest that EV-based Wnt3a delivery represents a novel therapeutic strategy for lung repair and regeneration after injury.

Direct and indirect effects of pathogenic bacteria on the integrity of intestinal barrier

Bacterial translocation is a pathological process involving migration of pathogenic bacteria across the intestinal barrier to enter the systemic circulation and gain access to distant organs. This phenomenon has been linked to a diverse range of diseases including inflammatory bowel disease, pancreatitis, and cancer. The intestinal barrier is an innate structure that maintains intestinal homeostasis. Pathogenic infections and dysbiosis can disrupt the integrity of the intestinal barrier, increasing its permeability, and thereby facilitating pathogen translocation. As translocation represents an essential step in pathogenesis, a clear understanding of how barrier integrity is disrupted and how this disruption facilitates bacterial translocation could identify new routes to effective prophylaxis and therapy. In this comprehensive review, we provide an in-depth analysis of bacterial translocation and intestinal barrier function. We discuss currently understood mechanisms of bacterial-enterocyte interactions, with a focus on tight junctions and endocytosis. We also discuss the emerging concept of bidirectional communication between the intestinal microbiota and other body systems. The intestinal tract has established 'axes' with various organs. Among our regulatory systems, the nervous, immune, and endocrine systems have been shown to play pivotal roles in barrier regulation. A mechanistic understanding of intestinal barrier regulation is crucial for the development of personalized management strategies for patients with bacterial translocation-related disorders. Advancing our knowledge of barrier regulation will pave the way for future research in this field and novel clinical intervention strategies.

Wnt Signaling Activation in Gingival Epithelial Cells and Macrophages of Experimental Periodontitis

Objective: Wingless/integrated (Wnt) signaling plays critical roles in maintaining environmental homeostasis and is also involved in the pathogenesis of inflammatory diseases. However, its role in macrophages during periodontitis is not well understood. The present study aims to investigate the interaction between Wnt signaling and macrophages in the context of periodontitis. Methods: Experimental periodontitis was induced in C57/BL6 mice using a Porphyromonas gingivalis (P.g)-associated ligature for 14 days. Immunohistochemistry was performed to study the expression of the pro-inflammatory cytokine tumor necrosis factor (TNF-α), the stabilization of β-catenin, and the macrophage marker F4/80 in the periodontal tissues. The effect of Wnt signaling on TNF-α was examined using Western blot analysis in Raw 264.7 murine macrophages stimulated by Wnt3a-conditioned medium, with or without Wnt3a antibody neutralization, and compared with primary cultured gingival epithelial cells (GECs). The effect of P.g lipopolysaccharide (LPS) on Wnt signaling was assessed by analyzing key components of the Wnt signaling pathway, including the activity of low-density lipoprotein receptor-related protein (LRP) 6 and nuclear accumulation of β-catenin in GEC and Raw 264.7 cells. Results: Over-expressions of TNF-α and activated β-catenin were presented in the macrophages in the gingiva from mice with P.g-associated ligature-induced periodontitis. The expression patterns of TNF-α and activated β-catenin were consistent with the expression of F4/80. In Raw 264.7 cells, activation of the Wnt signaling pathway led to an increase in TNF-α, but this effect was not observed in GEC. Additionally, treatment with LPS induced β-catenin accumulation and LRP6 activation in Raw 264.7 cells, which were blocked by the addition of Dickkopf-1(DKK1). Conclusions: Wnt signaling was aberrantly activated in the macrophages in experimental periodontitis. The activation of Wnt signaling in the macrophages may play a pro-inflammatory role in periodontitis. Targeting specific signaling pathways, such as the Wnt pathway, may hold promise for developing novel therapeutic interventions for periodontitis.

The adenomatous polyposis coli protein 30 years on

Mutations in the gene encoding the Adenomatous polyposis coli protein (APC) were discovered as driver mutations in colorectal cancers almost 30 years ago. Since then, the importance of APC in normal tissue homeostasis has been confirmed in a plethora of other (model) organisms spanning a large evolutionary space. APC is a multifunctional protein, with roles as a key scaffold protein in complexes involved in diverse signalling pathways, most prominently the Wnt signalling pathway. APC is also a cytoskeletal regulator with direct and indirect links to and impacts on all three major cytoskeletal networks. Correspondingly, a wide range of APC binding partners have been identified. Mutations in APC are extremely strongly associated with colorectal cancers, particularly those that result in the production of truncated proteins and the loss of significant regions from the remaining protein. Understanding the complement of its role in health and disease requires knowing the relationship between and regulation of its diverse functions and interactions. This in turn requires understanding its structural and biochemical features. Here we set out to provide a brief overview of the roles and function of APC and then explore its conservation and structure using the extensive sequence data, which is now available, and spans a broad range of taxonomy. This revealed conservation of APC across taxonomy and new relationships between different APC protein families.

WNT Co-Receptor LRP6 Is Critical for Zygotic Genome Activation and Embryonic Developmental Potential by Interacting with Oviductal Paracrine Ligand WNT2

Mammalian preimplantation development depends on the interaction between embryonic autocrine and maternal paracrine signaling. Despite the robust independence of preimplantation embryos, oviductal factors are thought to be critical to pregnancy success. However, how oviductal factors regulate embryonic development and the underlying mechanism remain unknown. In the present study, focusing on WNT signaling, which has been reported to be essential for developmental reprogramming after fertilization, we analyzed the receptor-ligand repertoire of preimplantation embryonic WNT signaling, and identified that the WNT co-receptor LRP6 is necessary for early cleavage and has a prolonged effect on preimplantation development. LRP6 inhibition significantly impeded zygotic genome activation and disrupted relevant epigenetic reprogramming. Focusing on the potential oviductal WNT ligands, we found WNT2 as the candidate interacting with embryonic LRP6. More importantly, we found that WNT2 supplementation in culture medium significantly promoted zygotic genome activation (ZGA) and improved blastocyst formation and quality following in vitro fertilization (IVF). In addition, WNT2 supplementation significantly improved implantation rate and pregnancy outcomes following embryo transfer. Collectively, our findings not only provide novel insight into how maternal factors regulate preimplantation development through maternal-embryonic communication, but they also propose a promising strategy for improving current IVF systems.

SUMOylation of RNF146 results in Axin degradation and activation of Wnt/β-catenin signaling to promote the progression of hepatocellular carcinoma

Aberrant SUMOylation contributes to the progression of hepatocellular carcinoma (HCC), yet the molecular mechanisms have not been well elucidated. RING-type E3 ubiquitin ligase RNF146 is a key regulator of the Wnt/β-catenin signaling pathway, which is frequently hyperactivated in HCC. Here, it is identified that RNF146 can be modified by SUMO3. By mutating all lysines in RNF146, we found that K19, K61, K174 and K175 are the major sites for SUMOylation. UBC9/PIAS3/MMS21 and SENP1/2/6 mediated the conjugation and deconjugation of SUMO3, respectively. Furthermore, SUMOylation of RNF146 promoted its nuclear localization, while deSUMOylation induced its cytoplasmic localization. Importantly, SUMOylation promotes the association of RNF146 with Axin to accelerate the ubiquitination and degradation of Axin. Intriguingly, only UBC9/PIAS3 and SENP1 can act at K19/K175 in RNF146 and affect its role in regulating the stability of Axin. In addition, inhibiting RNF146 SUMOylation suppressed the progression of HCC both in vitro and in vivo. And, patients with higher expression of RNF146 and UBC9 have the worst prognosis. Taken together, we conclude that RNF146 SUMOylation at K19/K175 promotes its association with Axin and accelerates Axin degradation, thereby enhancing β-catenin signaling and contributing to cancer progression. Our findings reveal that RNF146 SUMOylation is a potential therapeutic target in HCC.