Xenopus embryos provide a favorable material to dissect the sequential steps that lead to dorsal-ventral (D-V) and anterior-posterior (A-P) cell differentiation. Here, we analyze the signaling pathways involved in this process using loss-of-function and gain-of-function approaches. The initial step was provided by Hwa, a transmembrane protein that robustly activates early β-catenin signaling when microinjected into the ventral side of the embryo leading to complete twinned axes. The following step was the activation of Xenopus Nodal-related growth factors, which could rescue the depletion of β-catenin and were themselves blocked by the extracellular Nodal antagonists Cerberus-Short and Lefty. During gastrulation, the Spemann-Mangold organizer secretes a cocktail of growth factor antagonists, of which the BMP antagonists Chordin and Noggin could rescue simultaneously D-V and A-P tissues in β-catenin-depleted embryos. Surprisingly, this rescue occurred in the absence of any β-catenin transcriptional activity as measured by β-catenin activated Luciferase reporters. The Wnt antagonist Dickkopf (Dkk1) strongly synergized with the early Hwa signal by inhibiting late Wnt signals. Depletion of Sizzled (Szl), an antagonist of the Tolloid chordinase, was epistatic over the Hwa and Dkk1 synergy. BMP4 mRNA injection blocked Hwa-induced ectopic axes, and Dkk1 inhibited BMP signaling late, but not early, during gastrulation. Several unexpected findings were made, e.g., well-patterned complete embryonic axes are induced by Chordin or Nodal in β-catenin knockdown embryos, dorsalization by Lithium chloride (LiCl) is mediated by Nodals, Dkk1 exerts its anteriorizing and dorsalizing effects by regulating late BMP signaling, and the Dkk1 phenotype requires Szl.

Sympathetic activation triggered by chronic stress afflicting cancer survivors is an emerging modulator of tumorigenesis. Adrenergic blockade was previously associated with improving response to doxorubicin (DOX) in triple-negative breast cancer (TNBC), yet the precise underlying mechanisms remain obscure. The resilience of cancer stem cells (CSCs) during chemotherapy fosters resistance and relapse. Hypoxia-inducible factor-1α (HIF-1α) and β-catenin are intertwined transcriptional factors that enrich CSCs and evidence suggests that their expression could be modulated by systemic adrenergic signals. Herein, we aimed to explore the impact of adrenoreceptor blockade using carvedilol (CAR) on DOX and its potential to modulate CSCs overcoming chemoresistance. To achieve this aim, in vitro studies were conducted using adrenaline-preincubated MDA-MB-231 cells and in vivo studies using a chronic restraint stress-promoted solid tumor mouse model. Results revealed that adrenaline increased TNBC proliferation and induced a phenotypic switch reminiscent of CSCs, as evidenced by enhanced mammosphere formation. These results paralleled an increase in aldehyde dehydrogenase-1 (ALDH-1) and Nanog expression levels as well as HIF-1α and β-catenin upsurge. In vivo, larger tumor volumes were observed in mice under chronic stress compared to their unstressed counterparts. Adrenergic blockade using CAR, however, enhanced the impact DOX had on halting TNBC cell proliferation and tumor growth via enhanced apoptosis. CAR also curbed HIF-1α and β-catenin tumor levels subsequently suppressing ALDH-1 and SOX2. Our study unveils a central role for HIF-1α linking stress-induced sympathetic activation fueling CSC enrichment via the β-catenin pathway. It also highlights novel insights into CAR\'s capacity in reversing DOX chemoresistance in TNBC.

Background: Head and neck squamous cell carcinoma (HNSC) is a dangerous cancer that represents an important threat to human health. Niclosamide is an anti-helminthic drug that has received FDA approval. In drug repurposing screens, niclosamide was found to inhibit proliferative activity for a range of tumor types. Its functional effects in HNSC, however, have yet to be established. Methods: MTT and colony formation assays were used to explore the impact of niclosamide on the proliferation of HNSC cells, while wound healing and Transwell assays were employed to assess migration and invasivity. Flow cytometry and Western immunoblotting were respectively used to assess cellular apoptosis and protein expression patterns. An HNSC xenograft tumor model system was used to evaluate the in vivo antitumor activity of niclosamide, and immunofluorescent staining was employed to assess cleaved Caspase3 and Ki67 expression. The ability of niclosamide to prevent metastatic progression in vivo was assessed with a model of pulmonary metastasis. Results: These analyses revealed the ability of niclosamide to suppress HNSC cell migration, proliferation, and invasivity in vitro while promoting apoptotic death. From a mechanistic perspective, this drug suppressed Stat3 phosphorylation and β-catenin expression, while increasing cleaved Caspase3 levels in HNSC cells and reducing Bcl-2 levels. Importantly, this drug was able to suppress in vivo tumor growth and pulmonary metastasis formation, with immunofluorescent staining confirming that it reduced Ki67 levels and increased cleaved Caspase3 content. Conclusion: In conclusion, these analyses highlight the ability of niclosamide to inhibit HNSC cell migration and proliferative activity while provoking apoptotic death mediated via p-Stat3 and β-catenin pathway inactivation. Niclosamide thus holds promise for repurposing as a candidate drug for the more effective clinical management of HNSC.

Immune checkpoint therapy (ICT) has been shown to produce durable responses in various cancer patients. However, its efficacy is notably limited in hepatocellular carcinoma (HCC), with only a small percentage of patients responding positively to treatment. The mechanism underlying resistance to ICT in HCC remains poorly understood. Here, we showed that combination treatment of ICG-001, an inhibitor of the Wnt/β-catenin signaling pathway, with anti-PD-1 antibody effectively suppresses tumor growth and promotes the infiltration of immune cells such as DCs and CD8+ T cells in the tumor microenvironment (TME). By inhibiting the activity of β-catenin and blocking its binding to the transcription factor IKAROS family zinc finger 1 (IKZF1), ICG-001 upregulated the expression of CCL5. Moreover, IKZF1 regulated the activity of the CCL5 promoter and its endogenous expression. Through inhibition of the WNT/β-catenin signaling pathway, upregulation of the expression of CCL5 was achieved, which subsequently recruited more DCs into the TME via C-C motif chemokine receptor 5 (CCR5). This, in turn, resulted in an increase in the infiltration of CD8+ T cells in the TME, thereby enhancing the antitumor immune response. Analysis of a tissue microarray derived from HCC patient samples revealed a positive correlation between survival rate and prognosis and the expression levels of CCL5/CD8. In conclusion, our findings suggest that combined application of ICG-001 and anti-PD-1 antibody exhibits significantly enhanced antitumor efficacy. Hence, combining a WNT/β-catenin signaling pathway inhibitor with anti-PD-1 therapy may be a promising treatment strategy for patients with HCC.

The use of endosseous dental implants may become unfeasible in the presence of significant maxillary bone atrophy; thus, surgical techniques have been proposed to promote bone regeneration in such cases. However, such techniques are complex and may expose the patient to complications. Subperiosteal implants, being placed between the periosteum and the residual alveolar bone, are largely independent of bone thickness. Such devices had been abandoned due to the complexity of positioning and adaptation to the recipient bone site, but are nowadays witnessing an era of revival following the introduction of new acquisition procedures, new materials, and innovative manufacturing methods. We have analyzed the changes induced in gene and protein expression in C-12720 human osteoblasts by differently surface-modified TiO2 materials to verify their ability to promote bone formation. The TiO2 materials tested were (i) raw machined, (ii) electropolished with acid mixture, (iii) sand-blasted + acid-etched, (iv) AlTiColorTM surface, and (v) anodized. All five surfaces efficiently stimulated the expression of markers of osteoblastic differentiation, adhesion, and osteogenesis, such as RUNX2, osteocalcin, osterix, N-cadherin, β-catenin, and osteoprotegerin, while cell viability/proliferation was unaffected. Collectively, our observations document that presently available TiO2 materials are well suited for the manufacturing of modern subperiosteal implants.

Melanocytes, located in the epidermis\' basal layer, are responsible for melanin pigment production, crucial for skin coloration and protection against UV radiation-induced damage. Melanin synthesis is intricately regulated by various factors, including the Wnt signaling pathway, particularly mediated by the microphthalmia-associated transcription factor (MITF). While MITF is recognized as a key regulator of pigmentation, its regulation by the Wnt pathway remains poorly understood. This study investigates the role of Sfrp5pepD, a peptide antagonist of the Wnt signaling pathway, in modulating melanogenesis and its potential therapeutic implications for pigmentary disorders. To tackle this issue, we investigated smaller peptides frequently utilized in cosmetics or pharmaceuticals. Nevertheless, there is a significant scarcity of reports on peptides associated with melanin-related signal modulation or inhibiting melanin production. Results indicate that Sfrp5pepD effectively inhibits Wnt signaling by disrupting the interaction between Axin-1 and β-catenin, thus impeding downstream melanogenic processes. Additionally, Sfrp5pepD suppresses the interaction between MITF and β-catenin, inhibiting their nuclear translocation and downregulating melanogenic enzyme expression, ultimately reducing melanin production. These inhibitory effects are validated in cell culture models suggesting potential clinical applications for hyperpigmentation disorders. Overall, this study elucidates the intricate interplay between Wnt signaling and melanogenesis, highlighting Sfrp5pepD as a promising therapeutic agent for pigmentary disorders. Sfrp5pepD, with a molecular weight of less than 500 Da, is anticipated to penetrate the skin unlike SFRPs. This suggests a strong potential for their use as cosmetics or transdermal absorption agents. Additional investigation into its mechanisms and clinical significance is necessary to enhance its effectiveness in addressing melanin-related skin conditions.

Hepatocellular carcinoma (HCC) development is associated with altered modifications in DNA methylation, changing transcriptional regulation. Emerging evidence indicates that DNA methyltransferase 1 (DNMT1) plays a key role in the carcinogenesis process. This study aimed to investigate how pirfenidone (PFD) modifies this pathway and the effect generated by the association between c-Myc expression and DNMT1 activation. Rats F344 were used for HCC development using 50 mg/kg of diethylnitrosamine (DEN) and 25 mg/kg of 2-Acetylaminofluorene (2-AAF). The HCC/PFD group received simultaneous doses of 300 mg/kg of PFD. All treatments lasted 12 weeks. On the other hand, HepG2 cells were used to evaluate the effects of PFD in restoring DNA methylation in the presence of the inhibitor 5-Aza. Histopathological, biochemical, immunohistochemical, and western blot analysis were carried out and our findings showed that PFD treatment reduced the amount and size of tumors along with decreased Glipican-3, β-catenin, and c-Myc expression in nuclear fractions. Also, this treatment improved lipid metabolism by modulating PPARγ and SREBP1 signaling. Interestingly, PFD augmented DNMT1 and DNMT3a protein expression, which restores global methylation, both in our in vivo and in vitro models. In conclusion, our results suggest that PFD could slow down HCC development by controlling DNA methylation.

N6-methyladenosine (m6A) methylation plays a crucial role in various biological processes and the pathogenesis of human diseases. However, its role and mechanism in kidney fibrosis remain elusive. In this study, we show that the overall level of m6A methylated RNA was upregulated and the m6A methyltransferase METTL3 was induced in kidney tubular epithelial cells in mouse models and human kidney biopsies of chronic kidney disease (CKD). Proximal tubule-specific knockout of METTL3 in mice protected kidneys against developing fibrotic lesions after injury. Conversely, overexpression of METTL3 aggravated kidney fibrosis in vivo. Through bioinformatics analysis and experimental validation, we identified β-catenin mRNA as a major target of METTL3-mediated m6A modification, which could be recognized by a specific m6A reader, the insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3). METTL3 stabilized β-catenin mRNA, increased β-catenin protein and induced its downstream profibrotic genes, whereas either knockdown of IGF2BP3 or inhibiting β-catenin signaling abolished its effects. Collectively, these results indicate that METTL3 promotes kidney fibrosis by stimulating the m6A modification of β-catenin mRNA, leading to its stabilization and its downstream profibrotic genes expression. Our findings suggest that targeting METTL3/IGF2BP3/β-catenin pathway may be a novel strategy for the treatment of fibrotic CKD.

Ghost cell odontogenic carcinoma (GCOC) is defined as a rare type of odontogenic carcinoma that is characterized by ghost cells and occasional dentinoid. However, the current classification system based primarily on the presence of ghost cells has limitations in the diagnosis of GCOC and its histologic mimics including odontogenic carcinoma with dentinoid (OCD). This study reviewed previous studies on β-catenin nuclear translocation and WNT pathway mutations in GCOC and OCD and discussed the potential utility of a new molecular-based classification \"WNT pathway-altered malignant odontogenic tumor\" for these rare odontogenic tumors.

4-O-Methyl-ascochlorin (MAC), a derivative of the prenyl-phenol antibiotic ascochlorin extracted from the fungus Ascochyta viciae, shows anticarcinogenic effects on various cancer cells. 5-Fluorouracil (5-FU) is used to treat colorectal cancer (CRC); however, its efficacy must be enhanced. In this study, we investigated the molecular mechanisms by which MAC acts synergistically with 5-FU to inhibit cell proliferation and induce apoptosis in CRC cells. MAC enhanced the cytotoxic effects of 5-FU by suppressing the Akt/mTOR/p70S6K and Wnt/β-catenin signaling pathways. It also reduced the viability of 5-FU-resistant (5-FU-R) cells. Furthermore, expression of anti-apoptosis-related proteins and cancer stem-like cell (CSC) markers by 5-FU-R cells decreased in response to MAC. Similar to MAC, the knockdown of CTNNB1 induced apoptosis and reduced expression of mRNA encoding CRC markers in 5-FU-R cells. In summary, these results suggest that MAC and other β-catenin modulators may be useful in overcoming the 5-FU resistance of CRC cells.