Feigin, CY;Moreno, JA;Ramos, R;Mereby, SA;Alivisatos, A;Wang, W;van Amerongen, R;Camacho, J;Rasweiler, JJ;Behringer, RR;Ostrow, B;Plikus, MV;Mallarino, R;
PMID: 36961889 | DOI: 10.1126/sciadv.ade7511
Lateral flight membranes, or patagia, have evolved repeatedly in diverse mammalian lineages. While little is known about patagium development, its recurrent evolution may suggest a shared molecular basis. By combining transcriptomics, developmental experiments, and mouse transgenics, we demonstrate that lateral Wnt5a expression in the marsupial sugar glider (Petaurus breviceps) promotes the differentiation of its patagium primordium. We further show that this function of Wnt5a reprises ancestral roles in skin morphogenesis predating mammalian flight and has been convergently used during patagium evolution in eutherian bats. Moreover, we find that many genes involved in limb development have been redeployed during patagium outgrowth in both the sugar glider and bat. Together, our findings reveal that deeply conserved genetic toolkits contribute to the evolutionary transition to flight in mammals.
Duan X, Bradbury SR, Olsen BR, Berendsen AD.
PMID: 26899202 | DOI: 10.1016/j.matbio.2016.02.005.
Deficiency of vascular endothelial growth factor A (VEGF) has been associated with severe craniofacial anomalies in both humans and mice. Cranial neural crest cell (NCC)-derived VEGF regulates proliferation, vascularization and ossification of cartilage and membranous bone. However, the function of VEGF derived from specific subpopulations of NCCs in controlling unique aspects of craniofacial morphogenesis is not clear. In this study a conditional knockdown strategy was used to genetically delete Vegfa expression in Osterix (Osx) and collagen II (Col2)-expressing NCC descendants. No major defects in calvaria and mandibular morphogenesis were observed upon knockdown of VEGF in the Col2+ cell population. In contrast, loss of VEGF in Osx+ osteoblast progenitor cells led to reduced ossification of calvarial and mandibular bones without affecting the formation of cartilage templates in newborn mice. The early stages of ossification in the developing jaw revealed decreased initial mineralization levels and a reduced thickness of the collagen I (Col1)-positive bone template upon loss of VEGF in Osx+ precursors. Increased numbers of proliferating cells were detected within the jaw mesenchyme of mutant embryos. Explant culture assays revealed that mandibular osteogenesis occurred independently of paracrine VEGF action and vascular development. Reduced VEGF expression in mandibles coincided with increased phospho-Smad1/5 (P-Smad1/5) levels and bone morphogenetic protein 2 (Bmp2) expression in the jaw mesenchyme. We conclude that VEGF derived from Osx+ osteoblast progenitor cells is required for optimal ossification of developing mandibular bones and modulates mechanisms controlling BMP-dependent specification and expansion of the jaw mesenchyme.
DETERMINATION OF SINGLE NUCLEOTIDE POLYMORPHISM (RS566926) OF WNT5A IN NONSYNDROMIC CLEFT LIP AND PALATE IN A PAKISTANI POPULATION
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Anjum, R;Mehmood, S;Nagi, A;Shahzad, M;Chuadhry, S;
| DOI: 10.1016/j.oooo.2021.03.042
Background Orofacial clefts are the most common birth defects affecting 1 in 750 live births worldwide. Various genetic loci to be involved in nonsyndromic cleft lip and palate has been identified with a variation among populations. Wnt5a is expressed in the frontonasal prominence and maxillary process, which fuse to form the primary palate. Therefore, its dysregulation can lead to certain birth defects along with other diseases. Single nucleotide polymorphism (rs566926) in Wnt5A shows a significant association with nonsyndromic cleft lip and palate in Brazilian and European American populations. Objective The aim of the present study was to describe single nucleotide polymorphism (SNP; rs566926) in patients with nonsyndromic cleft lip and palate in a Pakistani population. Methods This study was conducted on 120 patients with nonsyndromic cleft lip and palate. Demographics and phenotypes were noted. Blood samples were collected in ethylenediaminetetraacetic acid vials. DNA was extracted followed by conventional polymerase chain reaction. SNP (566926) was determined by Sanger sequencing. Data were analyzed using NCBI Blast and SPSS (24.0). Results The mean age of n = 30 patients was 51.33 ± 61.33 months. Sixty percent were male and 40% were female. Regarding cleft types, 70% were both cleft lip and palate, 26% cleft lip only, and 3.3% cleft palate only. Heterozygous polymorphism (T/G) was seen in 33.3% of patients with both cleft lip and palate with bilateral involvement and heterozygous polymorphism (T) was seen in 16.6%. Conclusions SNP in the WNT5A gene is associated with cleft lip and palate, supporting its involvement in pathogenesis of cleft lip and palate. Further studies are recommended to determine the role of Wnt5a genes during craniofacial development.
Mizutani M, Wu JC, Nusse R.
PMID: - | DOI: 10.1161/JAHA.115.002457
Background The adult mammalian heart responds to cardiac injury by formation of persistent fibrotic scar that eventually leads to heart failure. In contrast, the neonatal mammalian heart reacts to injury by the development of transient fibrotic tissue that is eventually replaced by regenerated cardiomyocytes. How fibrosis occurs in the neonatal mammalian heart remains unknown. To start elucidating the molecular underpinnings of neonatal cardiac fibrosis, we investigated Wnt signaling in the neonatal heart after cryoinjury.
Methods and Results Using expression of the Wnt target gene Axin2 as an indicator of Wnt/β‐catenin signaling activation, we discovered that epicardial cells in the ventricles are responsive to Wnt in the uninjured neonatal heart. Lineage‐tracing studies of these Wnt‐responsive epicardial cells showed that they undergo epithelial‐to‐mesenchymal transition and infiltrate into the subepicardial space and exhibit fibroblast phenotypes after injury. In addition, we showed that—similar to adult ischemic injury—neonatal cryoinjury results in activation of Wnt signaling in cardiac fibroblasts near injured areas. Furthermore, through in situ hybridization of all 19 Wnt ligands in injured neonatal hearts, we observed upregulation of Wnt ligands (Wnt2b, Wnt5a, and Wnt9a) that had not been implicated in the adult cardiac injury response.
Conclusions These results demonstrate that cryoinjury in neonatal heart leads to the formation of fibrotic tissue that involves Wnt‐responsive epicardial cells undergoing epithelial‐to‐mesenchymal transition to give rise to fibroblasts and activation of Wnt signaling in resident cardiac fibroblasts.
WNT signaling in pre-granulosa cells is required for ovarian folliculogenesis and female fertility
Development (Cambridge, England)
Habara, O;Logan, CY;Kanai-Azuma, M;Nusse, R;Takase, HM;
PMID: 33914868 | DOI: 10.1242/dev.198846
In mammalian ovaries, immature oocytes are reserved in primordial follicles until their activation for potential ovulation. Precise control of primordial follicle activation (PFA) is essential for reproduction, but how this is achieved is unclear. Here, we show that canonical wingless-type MMTV integration site family (WNT) signaling is pivotal for pre-granulosa cell (pre-GC) activation during PFA. We identified several WNT ligands expressed in pre-GCs that act in an autocrine manner. Inhibition of WNT secretion from pre-GCs/GCs by conditional knockout (cKO) of the wntless (Wls) gene led to female infertility. In Wls cKO mice, GC layer thickness was greatly reduced in growing follicles, which resulted in impaired oocyte growth with both an abnormal, sustained nuclear localization of forkhead box O3 (FOXO3) and reduced phosphorylation of ribosomal protein S6 (RPS6). Constitutive stabilization of β-catenin (CTNNB1) in pre-GCs/GCs induced morphological changes of pre-GCs from a squamous into a cuboidal form, though it did not influence oocyte activation. Our results reveal that canonical WNT signaling plays a permissive role in the transition of pre-GCs to GCs, which is an essential step to support oocyte growth.
Tamma R, Annese T, Ruggieri S, Marzullo A, Nico B, Ribatti D.
PMID: 29761299 | DOI: 10.1007/s10735-018-9777-0
Gastric cancer is the fifth most common cancer and third leading cause of cancer-related death worldwide. Several studies on angiogenic blocking agents in gastric cancer revealing promising results by the use of monoclonal antibodies against VEGFA or its receptor VEGFR2 or against VEGFA activating pathway. The validation of biomarkers useful to better organize the clinical trials involving anti-angiogenic therapies is crucial. Molecular markers such as RNA are increasingly used for cancer diagnosis, prognosis, and therapy guidance as in the case of the targeted therapies concerning the inhibition of angiogenesis. The aim of this study is to set the conditions for evaluating the expression of VEGFA and VEGFR2 in gastric cancer specimens and in healthy gastric mucosa by the use of RNAscope, a novel RNA in situ hybridization (ISH) method that allows the visualization of a specific gene expression in individual cells. We found the increased expression of VEGFA in the tubular glands and VEGFR2 in the endothelium of gastric cancer samples mainly in the T2, T3 and T4 stages of tumor progression as compared to the healthy controls. These results obtained by the application of this highly sensitive method for oligonucleotide detection the role of angiogenesis in gastric cancer progression already highlighted by conventional immunohistochemical methods, and offer significant promise as a new platform for developing and implementing RNA-based molecular diagnostics also in the conditions in which immunohistochemistry is not applicable.
Cellular and molecular gastroenterology and hepatology
Kim, TY;Kim, S;Kim, Y;Lee, YS;Lee, S;Lee, SH;Kweon, MN;
PMID: 34971821 | DOI: 10.1016/j.jcmgh.2021.12.015
Dietary signals are known to modulate stemness and tumorigenicity of intestinal progenitors; however, the impact of a high-fat diet (HFD) on the intestinal stem cell (ISC) niche and its association with colorectal cancer remains unclear. Thus, we aimed to investigate how a HFD affects the ISC niche and its regulatory factors.Mice were fed a purified diet (PD) or HFD for 2 months. The expression levels of ISC-related markers, ISC-supportive signals, and Wnt2b were assessed with real-time quantitative polymerase chain reaction, in situ hybridization, and immunofluorescence staining. RNA sequencing and metabolic function were analyzed in mesenchymal stromal cells (MSCs) from PD- and HFD-fed mice. Fecal microbiota were analyzed by 16s rRNA sequencing. Bile salt hydrolase activity and bile acid (BA) levels were measured.We found that expression of CD44 and Wnt signal-related genes was higher in the colonic crypts of HFD-fed mice than in those fed a PD. Within the ISC niche, MSCs were expanded and secreted predominant levels of Wnt2b in the colon of HFD-fed mice. Of note, increased energy metabolism and cancer-associated fibroblast (CAF)-like properties were found in the colonic MSCs of HFD-fed mice. Moreover, colonic MSCs from HFD-fed mice promoted the growth of tumorigenic properties and accelerated the expression of cancer stem cell (CSC)-related markers in colon organoids. In particular, production of primary and secondary BAs was increased through the expansion of bile salt hydrolase-encoding bacteria in HFD-fed mice. Most importantly, BAs-FXR interaction stimulated Wnt2b production in colonic CAF-like MSCs.HFD-induced colonic CAF-like MSCs play an indispensable role in balancing the properties of CSCs through activation of the BAs-FXR axis.
Rehman, R;Miller, M;Krishnamurthy, SS;Kjell, J;Elsayed, L;Hauck, SM;Olde Heuvel, F;Conquest, A;Chandrasekar, A;Ludolph, A;Boeckers, T;Mulaw, MA;Goetz, M;Morganti-Kossmann, MC;Takeoka, A;Roselli, F;
PMID: 36577378 | DOI: 10.1016/j.celrep.2022.111867
The complexity of signaling events and cellular responses unfolding in neuronal, glial, and immune cells upon traumatic brain injury (TBI) constitutes an obstacle in elucidating pathophysiological links and targets for intervention. We use array phosphoproteomics in a murine mild blunt TBI to reconstruct the temporal dynamics of tyrosine-kinase signaling in TBI and then scrutinize the large-scale effects of perturbation of Met/HGFR, VEGFR1, and Btk signaling by small molecules. We show Met/HGFR as a selective modifier of early microglial response and that Met/HGFR blockade prevents the induction of microglial inflammatory mediators, of reactive microglia morphology, and TBI-associated responses in neurons and vasculature. Both acute and prolonged Met/HGFR inhibition ameliorate neuronal survival and motor recovery. Early elevation of HGF itself in the cerebrospinal fluid of TBI patients suggests that this mechanism has translational value in human subjects. Our findings identify Met/HGFR as a modulator of early neuroinflammation in TBI with promising translational potential.
Snowball J, Ambalavanan M, Whitsett J, Sinner D.
PMID: 26093309 | DOI: 10.1016/j.ydbio.2015.06.009.
Tracheobronchomalacia is a common congenital defect in which the walls of the trachea and bronchi lack of adequate cartilage required for support of the airways. Deletion of Wls, a cargo receptor mediating Wnt ligand secretion, in the embryonic endoderm using ShhCre mice inhibited formation of tracheal-bronchial cartilaginous rings. The normal dorsal-ventral patterning of tracheal mesenchyme was lost. Smooth muscle cells, identified by Acta2 staining, were aberrantly located in ventral mesenchyme of the trachea, normally the region of Sox9 expression in cartilage progenitors. Wnt/β-catenin activity, indicated by Axin2 LacZ reporter, was decreased in tracheal mesenchyme of Wlsf/f;ShhCre/+ embryos. Proliferation of chondroblasts was decreased and reciprocally, proliferation of smooth muscle cells was increased in Wlsf/f;ShhCre/+ tracheal tissue. Expression of Tbx4, Tbx5, Msx1 and Msx2, known to mediate cartilage and muscle patterning, were decreased in tracheal mesenchyme of Wlsf/f;ShhCre/+ embryos. Ex vivo studies demonstrated that Wnt7b and Wnt5a, expressed by the epithelium of developing trachea, and active Wnt/β-catenin signaling are required for tracheal chondrogenesis before formation of mesenchymal condensations. In conclusion, Wnt ligands produced by the tracheal epithelium pattern the tracheal mesenchyme via modulation of gene expression and cell proliferation required for proper tracheal cartilage and smooth muscle differentiation.
Rodríguez, JMM;Fonfara, S;Hetzel, U;Kipar, A;
PMID: 34955067 | DOI: 10.1177/03009858211062631
The sequence of pathological events in feline hypertrophic cardiomyopathy (fHCM) is still largely unknown, although we know that fHCM is characterized by interstitial remodeling in a macrophage-driven pro-inflammatory environment and that myocardial ischemia might contribute to its progression. This study aimed to gain further insights into the structural changes associated with interstitial remodeling in fHCM with special focus on the myocardial microvasculature and the phenotype of the interstitial cells. Twenty-eight hearts (16 hearts with fHCM and 12 without cardiac disease) were evaluated in the current study, with immunohistochemistry, RNA-in situ hybridization, and transmission electron microscopy. Morphometrical evaluations revealed a statistically significant lower microvascular density in fHCM. This was associated with structural alterations in capillaries that go along with a widening of the interstitium due to the accumulation of edema fluid, collagen fibers, and mononuclear cells that also proliferated locally. The interstitial cells were mainly of fibroblastic or vascular phenotype, with a substantial contribution of predominantly resident macrophages. A large proportion expressed CD34 mRNA, which suggests a progenitor cell potential. Our results indicate that microvascular alterations are key events in the pathogenesis of fHCM and that myocardial interstitial cell populations with CD34+ phenotype play a role in the pathogenesis of the disease.
Girolamo F, Errede M, Longo G, Annese T, Alias C, Ferrara G, Morando S, Trojano M, Kerlero de Rosbo N, Uccelli A and Virgintino D
PMID: 30870435 | DOI: 10.1371/journal.pone.0213508
During experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis associated with blood-brain barrier (BBB) disruption, oligodendrocyte precursor cells (OPCs) overexpress proteoglycan nerve/glial antigen 2 (NG2), proliferate, and make contacts with the microvessel wall. To explore whether OPCs may actually be recruited within the neurovascular unit (NVU), de facto intervening in its cellular and molecular composition, we quantified by immunoconfocal morphometry the presence of OPCs in contact with brain microvessels, during postnatal cerebral cortex vascularization at postnatal day 6, in wild-type (WT) and NG2 knock-out (NG2KO) mice, and in the cortex of adult naive and EAE-affected WT and NG2KO mice. As observed in WT mice during postnatal development, a higher number of juxtavascular and perivascular OPCs was revealed in adult WT mice during EAE compared to adult naive WT mice. In EAE-affected mice, OPCs were mostly associated with microvessels that showed altered claudin-5 and occludin tight junction (TJ) staining patterns and barrier leakage. In contrast, EAE-affected NG2KO mice, which did not show any significant increase in vessel-associated OPCs, seemed to retain better preserved TJs and BBB integrity. As expected, absence of NG2, in both OPCs and pericytes, led to a reduced content of vessel basal lamina molecules, laminin, collagen VI, and collagen IV. In addition, analysis of the major ligand/receptor systems known to promote OPC proliferation and migration indicated that vascular endothelial growth factor A (VEGF-A), platelet-derived growth factor-AA (PDGF-AA), and the transforming growth factor-beta (TGF-beta) were the molecules most likely involved in proliferation and recruitment of vascular OPCs during EAE. These results were confirmed by real time-PCR that showed Fgf2, Pdgfa and Tgfb expression on isolated cerebral cortex microvessels and by dual RNAscope-immunohistochemistry/in situ hybridization (IHC/ISH), which detected Vegfa and Vegfr2 transcripts on cerebral cortex sections. Overall, this study suggests that vascular OPCs, in virtue of their developmental arrangement and response to neuroinflammation and growth factors, could be integrated among the classical NVU cell components. Moreover, the synchronized activation of vascular OPCs and pericytes during both BBB development and dysfunction, points to NG2 as a key regulator of vascular interactions.
Guerrero-Juarez, CF;Lee, GH;Liu, Y;Wang, S;Karikomi, M;Sha, Y;Chow, RY;Nguyen, TTL;Iglesias, VS;Aasi, S;Drummond, ML;Nie, Q;Sarin, K;Atwood, SX;
PMID: 35687691 | DOI: 10.1126/sciadv.abm7981
How basal cell carcinoma (BCC) interacts with its tumor microenvironment to promote growth is unclear. We use singe-cell RNA sequencing to define the human BCC ecosystem and discriminate between normal and malignant epithelial cells. We identify spatial biomarkers of tumors and their surrounding stroma that reinforce the heterogeneity of each tissue type. Combining pseudotime, RNA velocity-PAGA, cellular entropy, and regulon analysis in stromal cells reveals a cancer-specific rewiring of fibroblasts, where STAT1, TGF-β, and inflammatory signals induce a noncanonical WNT5A program that maintains the stromal inflammatory state. Cell-cell communication modeling suggests that tumors respond to the sudden burst of fibroblast-specific inflammatory signaling pathways by producing heat shock proteins, whose expression we validated in situ. Last, dose-dependent treatment with an HSP70 inhibitor suppresses in vitro vismodegib-resistant BCC cell growth, Hedgehog signaling, and in vivo tumor growth in a BCC mouse model, validating HSP70's essential role in tumor growth and reinforcing the critical nature of tumor microenvironment cross-talk in BCC progression.
