Project description:Assaying gene expression in sutural bone fragments from patients diagnosed with non-syndromic craniosynostosis. Sutural fragments were collected from both the fused and patent cranial suture of infants during cranial vault reconstruction. Gene expression was compared between the patent and fused sutures using the paired t-test. The aim was to identify thoses genes significantly differentially expressed in fused suture relative to patent.
Project description:Assaying gene expression in sutural bone fragments from patients diagnosed with non-syndromic craniosynostosis. Sutural fragments were collected from both the fused and patent cranial suture of infants during cranial vault reconstruction. Gene expression was compared between the patent and fused sutures using the paired t-test. The aim was to identify thoses genes significantly differentially expressed in fused suture relative to patent. Total RNA isolated from patent and fused human cranial sutures was assayed. Expression in synostosed suture was compared to patent suture.
Project description:Purpose: The cranial suture is a fibrous joint, and similar to the growth plates of the skeletal long bone, they serve as the major centers of calvarial vault morphogenesis. Our group’s identification of a skeletal stem cell isolated from the mouse tibial growth plate prompted us to investigate whether these skeletal stem cells are also resident in the mouse cranial sutures and if they govern postnatal suture patency or fusion. Results: We preformed a spatio-temporal profiling of the mouse cranial sutures by flow cytometry, demonstrating a significant decrease in the temporal representation of skeletal stem cells in fusing versus patent sutures. Moreover, canonical Wnt signaling has a significant impact on skeletal stem cells proliferation and thus representation within the suture, dictating fate: fusion or patency. Breeding an Axin2+/-LacZ mouse, with enhanced activation of canonical Wnt signaling to a Twist1+/− mouse, harboring a coronal craniosynostosis enriched the skeletal stem cell pool in coronal sutures, thereby preventing Twist1+/− craniosynostosis. Conclusions: Our findings suggest an imbalance and/or decrease in resident skeletal stem cells within the cranial sutures gives rise to craniosynostosis, however, restoring this representation by enriching skeletal stem cells within the suture can maintain patency.
Project description:Purpose: The cranial suture is a fibrous joint, and similar to the growth plates of the skeletal long bone, they serve as the major centers of calvarial vault morphogenesis. Our group’s identification of a skeletal stem cell isolated from the mouse tibial growth plate prompted us to investigate whether these skeletal stem cells are also resident in the mouse cranial sutures and if they govern postnatal suture patency or fusion. Results: We preformed a spatio-temporal profiling of the mouse cranial sutures by flow cytometry, demonstrating a significant decrease in the temporal representation of skeletal stem cells in fusing versus patent sutures. Moreover, canonical Wnt signaling has a significant impact on skeletal stem cells proliferation and thus representation within the suture, dictating fate: fusion or patency. Breeding an Axin2+/-LacZ mouse, with enhanced activation of canonical Wnt signaling to a Twist1+/− mouse, harboring a coronal craniosynostosis enriched the skeletal stem cell pool in coronal sutures, thereby preventing Twist1+/− craniosynostosis. Conclusions: Our findings suggest an imbalance and/or decrease in resident skeletal stem cells within the cranial sutures gives rise to craniosynostosis, however, restoring this representation by enriching skeletal stem cells within the suture can maintain patency.
Project description:Craniosynostosis is a disease defined by premature fusion of one or more cranial sutures. The mechanistic pathology of isolated single-suture craniosynostosis is complex and while a number of genetic biomarkers and environmental predispositions have been identified, in many cases the causes remain controversial and inconclusive at best. After controlling for variables contributing to potential bias, FGF7, SFRP4, and VCAM1 emerged as potential genetic biomarkers for single-suture craniosynostosis due to their significantly large changes in gene expression compared to the control population. Furthermore, pathway analysis implicated focal adhesion and extracellular matrix (ECM)-receptor interaction as differentially regulated gene networks when comparing all cases of single-suture synostosis and controls. Lastly, overall gene expression was found to be highly conserved between coronal and metopic cases, as evidenced by the fact that WNT2 and IGFBP2 were the only differentially regulated genes identified in a direct comparison. These results not only confirm the roles of previously reported craniosynostosis-related targets but also introduce novel genetic biomarkers and pathways that may play critical roles in its pathogenesis. In this study, gene expression data from 199 patients with isolated sagittal (n= 100), unilateral coronal (n = 50), and metopic (n = 49) synostosis are compared against both a control population (n = 50), as well as each other.
Project description:Craniosynostosis is a disease defined by premature fusion of one or more cranial sutures. The mechanistic pathology of isolated single-suture craniosynostosis is complex and while a number of genetic biomarkers and environmental predispositions have been identified, in many cases the causes remain controversial and inconclusive at best. After controlling for variables contributing to potential bias, FGF7, SFRP4, and VCAM1 emerged as potential genetic biomarkers for single-suture craniosynostosis due to their significantly large changes in gene expression compared to the control population. Furthermore, pathway analysis implicated focal adhesion and extracellular matrix (ECM)-receptor interaction as differentially regulated gene networks when comparing all cases of single-suture synostosis and controls. Lastly, overall gene expression was found to be highly conserved between coronal and metopic cases, as evidenced by the fact that WNT2 and IGFBP2 were the only differentially regulated genes identified in a direct comparison. These results not only confirm the roles of previously reported craniosynostosis-related targets but also introduce novel genetic biomarkers and pathways that may play critical roles in its pathogenesis.
Project description:Craniosynostosis (CS) is a common birth defect due to the premature fusion of one or more cranial sutures. It manifests with abnormal skull shape and is associated with significant morbidities such as increased intracranial pressure, vision problems, and learning disabilities. Nonsyndromic craniosynostosis (NCS) occurs without any other associated birth defects and/or developmental delays and accounts for approximately 75% of all cases. Synostosis of the sagittal suture is the most common NCS subtype, accounting for 45-58% of all cases. Currently, surgical treatment is the only option to reshape the skull and allow for proper cranial growth. This surgical treatment is extensive and performed during the first year of life. Only one other study has examined the proteomic profile of cranial suture tissue derived from NCS patients. In order to understand how different proteins play a role in premature suture fusion and to potentially identify proteins that can serve as diagnostic and prognostic biomarkers for NCS, we identified biologically relevant differentially expressed proteins in NCS-derived tissues representing different stages in suture development.
Project description:Craniosynostosis (CS) is the congenital premature fusion of one or more cranial sutures and represents the more prevalent craniofacial malformation in humans, with an overall incidence of 1 out of 2000-3000 live births. Non-syndromic craniosynostoses (NSC) are believed to be multifactorial disorders, with a strong genetic component, due to possible gene–gene or gene–environment interactions that remain to be clearly identified. In this study we delved into the molecular signaling acting in calvarial tissue and cells from patients affected by nonsynodromic midline craniosynostosis, using a comparative analysis between fused and unfused sutures of each affected individuals. Using comparative microarray tissue gene expression profiling we have identified a subset of genes involved in the structure and function of the primary cilium, including the Bardet-Biedl syndrome 9 (BBS9) gene, which was recently associated to sagittal synostosis in a GWAS study. We therefore characterized BBS9 expression and cilium-related signaling in cells isolated from patients’ calvarial bone.