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Archives of Oral Biology Sep 2023Apert syndrome, an autosomal dominant congenital disorder characterized by craniosynostosis, is caused by a missense mutation (S252W or P253R) in fibroblast growth...
OBJECTIVE
Apert syndrome, an autosomal dominant congenital disorder characterized by craniosynostosis, is caused by a missense mutation (S252W or P253R) in fibroblast growth factor receptor 2 (FGFR2). Exosomes are naturally occurring carriers that deliver nucleic acids, including small interfering RNA (siRNA), to induce gene silencing. This study aimed to develop siRNA-loaded exosomes (Ex-siRNA) to silence the Fgfr2 gain-of-function mutation, thereby inhibiting the increased osteoblastic differentiation caused by the constitutive activation of FGFR2 signaling in calvarial osteoblastic cells isolated from Apert syndrome model mice.
DESIGN
Primary calvarial osteoblast-like cells were isolated from the embryonic calvarial sutures of the Apert syndrome model (Fgfr2) and littermate wild-type mice (Ap-Ob and Wt-Ob, respectively). Exosomes were extracted from the serum of wild-type mice, validated using biomarkers, and used to encapsulate siRNAs. After exosome-mediated siRNA transfection, cells were analyzed under a fluorescence microscope to validate the delivery of Ex-siRNA, followed by western blot and real-time reverse transcription polymerase chain reaction analyses.
RESULTS
After 24 h of Ex-siRNA delivery in both Ap-Ob and Wt-Ob, siRNA-loaded exosome delivery was validated. Moreover, p44/42 mitogen-activated protein kinase (MAPK) phosphorylation, runt-related transcription factor 2 (Runx2), and collagen type 1 alpha 1 (Col1a1) mRNA expression, and alkaline phosphatase (ALP) activity were significantly increased in Ap-Ob. The levels of phospho-p44/42 protein, Runx2, Col1a1, and ALP were significantly decreased after Ex-siRNA transfection but did not affect Wt-Ob.
CONCLUSIONS
These results indicate that exosome-mediated delivery of siRNA targeting Fgfr2 is a potential non-invasive treatment for aberrant FGF/FGFR signaling.
Topics: Mice; Animals; Acrocephalosyndactylia; Core Binding Factor Alpha 1 Subunit; RNA, Small Interfering; Exosomes; Cell Differentiation; Osteoblasts
PubMed: 37348363
DOI: 10.1016/j.archoralbio.2023.105753 -
Advances and Technical Standards in... 2023Apert syndrome is characterized by a wide spectrum of craniofacial clinical features that have been successfully addressed via a variety of midface advancement... (Review)
Review
Apert syndrome is characterized by a wide spectrum of craniofacial clinical features that have been successfully addressed via a variety of midface advancement techniques. Although surgeons have individual preferences as to which specific procedures should be performed to best treat Apert patients, craniofacial plastic surgeons, working in tandem with pediatric neurosurgeons, can identify and evaluate functional limitations and facial morphologic disproportions, and establish appropriate criteria for effective midface advancement technique indication and selection. The purpose of this review article is to present and discuss our rationale for midface advancement technique selection based upon the most common craniofacial characteristics presented by Apert syndrome patients. The present article also provides a grading system that stratifies as major, moderate, and mild, the effect of each midface advancement technique on the different types of Apert syndrome facial features. Surgeons should take into consideration the maximum effect and benefit of each craniofacial osteotomy and how these procedures will alter the craniofacial skeleton. By understanding the long-term effect of each osteotomy on the most common craniofacial characteristics of Apert syndrome patients, craniofacial plastic surgeons and neurosurgeons will be able to customize the surgical procedures they perform in order to achieve the best possible outcomes.
Topics: Humans; Child; Acrocephalosyndactylia; Retrospective Studies; Osteotomy, Le Fort; Face
PubMed: 37318579
DOI: 10.1007/978-3-031-28202-7_13 -
The Journal of Craniofacial Surgery Oct 2023Saethre-Chotzen syndrome (SCS) is a syndromic craniosynostosis with pathogenic variants in the TWIST1 gene showing a broad phenotypic spectrum. Controversies exist in...
Saethre-Chotzen syndrome (SCS) is a syndromic craniosynostosis with pathogenic variants in the TWIST1 gene showing a broad phenotypic spectrum. Controversies exist in the literature regarding surgical management with single one-stage versus patient-tailored surgery and the related reoperation rate for intracranial hypertension of up to 42%. At our center, SCS patients are offered patient-tailored surgery with single-stage fronto-orbital advancement and remodeling or fronto-orbital advancement and remodeling and posterior distraction in an individually determined order. The authors' database identified 35 confirmed SCS patients between 1999 and 2022. Involved sutures in craniosynostosis were left unicoronal (22.9%), bicoronal (22.9%), sagittal (8.6%), bicoronal and sagittal (5.7%), right unicoronal (2.9%), bicoronal and metopic (2.9%), bicoronal, sagittal and metopic (2.9%), and bilateral lambdoid (2.9%). There was pansynostosis in 8.6% and no craniosynostosis in 14.3% of the patients. Twenty-six patients, 10 females, and 16 males were operated on. Mean age at the first surgery was 1.70 years, and 3.86 years at the second surgery. Eleven of 26 patients had invasive intracranial pressure monitoring. Three patients presented with papilledema before the first surgery and 4 afterward. Four of the 26 operated patients were operated initially elsewhere. The other 22 patients were initially referred to our unit and underwent patient-tailored surgery. Nine of these patients (41%) had a second surgery, and 3 (14%) of them were because of raised intracranial pressure. Seven (27%) of all operated patients had a complication. Median follow-up was 13.98 years (range, 1.85-18.08). Patient-tailored surgery in a specialized center and long-term follow-up allow for a low reoperation rate for intracranial hypertension.
Topics: Male; Female; Humans; Infant; Acrocephalosyndactylia; Reoperation; Craniosynostoses; Skull; Intracranial Hypertension
PubMed: 37226293
DOI: 10.1097/SCS.0000000000009429 -
Genetics Aug 2023TWIST1 is a basic helix-loop-helix (bHLH) transcription factor in humans that functions in mesoderm differentiation. TWIST1 primarily regulates genes as a...
TWIST1 is a basic helix-loop-helix (bHLH) transcription factor in humans that functions in mesoderm differentiation. TWIST1 primarily regulates genes as a transcriptional repressor often through TWIST-Box domain-mediated protein-protein interactions. The TWIST-Box also can function as an activation domain requiring 3 conserved, equidistant amino acids (LXXXFXXXR). Autosomal dominant mutations in TWIST1, including 2 reported in these conserved amino acids (F187L and R191M), lead to craniofacial defects in Saethre-Chotzen syndrome (SCS). Caenorhabditis elegans has a single TWIST1 homolog, HLH-8, that functions in the differentiation of the muscles responsible for egg laying and defecation. Null alleles in hlh-8 lead to severely egg-laying defective and constipated animals due to defects in the corresponding muscles. TWIST1 and HLH-8 share sequence identity in their bHLH regions; however, the domain responsible for the transcriptional activity of HLH-8 is unknown. Sequence alignment suggests that HLH-8 has a TWIST-Box LXXXFXXXR motif; however, its function also is unknown. CRISPR/Cas9 genome editing was utilized to generate a domain deletion and several missense mutations, including those analogous to SCS patients, in the 3 conserved HLH-8 amino acids to investigate their functional role. The TWIST-Box alleles did not phenocopy hlh-8 null mutants. The strongest phenotype detected was a retentive (Ret) phenotype with late-stage embryos in the hermaphrodite uterus. Further, GFP reporters of HLH-8 downstream target genes (arg-1::gfp and egl-15::gfp) revealed tissue-specific, target-specific, and allele-specific defects. Overall, the TWIST-Box in HLH-8 is partially required for the protein's transcriptional activity, and the conserved amino acids contribute unequally to the domain's function.
Topics: Animals; Female; Humans; Acrocephalosyndactylia; Basic Helix-Loop-Helix Transcription Factors; Caenorhabditis elegans; Mutation; Transcription Factors; Twist-Related Protein 1
PubMed: 37067863
DOI: 10.1093/genetics/iyad066 -
Plastic and Reconstructive Surgery Aug 2023CRISPR-Cas genome editing tools are among the most substantial advances in the life sciences in modern history. Single-dose gene therapies to correct pathogenic...
CRISPR-Cas genome editing tools are among the most substantial advances in the life sciences in modern history. Single-dose gene therapies to correct pathogenic mutations have moved quickly from bench to bedside, with several therapeutics designed by CRISPR pioneers entering various stages of clinical investigation. Applications of these genetic technologies are poised to reshape the practice of both medicine and surgery. Many of the most morbid conditions treated by craniofacial surgeons are syndromic craniosynostoses caused by mutations in fibroblast growth factor receptor genes, including Apert, Pfeiffer, Crouzon, and Muenke syndromes. The fact that pathogenic mutations in these genes are recurrent in the majority of affected families presents a unique opportunity to develop "off-the-shelf" gene editing therapies to correct these mutations in affected children. The therapeutic potential of these interventions could reshape pediatric craniofacial surgery, potentially first eliminating the need for midface advancement procedures in affected children.
Topics: Child; Humans; Craniosynostoses; Mutation; Face; Specialties, Surgical; Craniofacial Dysostosis; Acrocephalosyndactylia
PubMed: 36912935
DOI: 10.1097/PRS.0000000000010402 -
Plastic and Reconstructive Surgery Sep 2023Crouzon syndrome is characterized by complex craniosynostosis and midfacial hypoplasia. Where frontofacial monobloc advancement (FFMBA) is indicated, the method of...
BACKGROUND
Crouzon syndrome is characterized by complex craniosynostosis and midfacial hypoplasia. Where frontofacial monobloc advancement (FFMBA) is indicated, the method of distraction used to achieve advancement holds an element of equipoise. This two-center retrospective cohort study quantifies the movements produced by internal or external distraction methods used for FFMBA. Using shape analysis, this study evaluates whether the different distraction forces cause plastic deformity of the frontofacial segment, producing distinct morphologic outcomes.
METHODS
Patients with Crouzon syndrome who underwent FFMBA with internal distraction [Hôpital Necker-Enfants Malades (Paris, France)] or external distraction [Great Ormond Street Hospital for Children (London, United Kingdom)] were compared. Digital Imaging and Communications in Medicine files of preoperative and postoperative computed tomographic scans were converted to three-dimensional bone meshes and skeletal movements were assessed using nonrigid iterative closest point registration. Displacements were visualized using color maps and statistical analysis of the vectors was undertaken.
RESULTS
Fifty-one patients met the strict inclusion criteria. Twenty-five underwent FFMBA with external distraction and 26 with internal distraction. External distraction provides a preferential midfacial advancement, whereas internal distractors produce a more positive movement at the lateral orbital rim. This confers good orbital protection but does not advance the central midface to the same extent. Vector analysis confirmed this to be statistically significant ( P < 0.01).
CONCLUSIONS
Morphologic changes resulting from monobloc surgery differ depending on the distraction technique used. Although the relative merits of internal and external distraction still stand, it may be that external distraction is more suited to addressing the midfacial biconcavity seen in syndromic craniosynostosis.
CLINICAL QUESTION/LEVEL OF EVIDENCE
Therapeutic, III.
Topics: Child; Humans; Retrospective Studies; Osteogenesis, Distraction; Facial Bones; Craniofacial Dysostosis; Craniosynostoses; Acrocephalosyndactylia
PubMed: 36847681
DOI: 10.1097/PRS.0000000000010331 -
Plastic and Reconstructive Surgery Mar 2023
Topics: Humans; Infant; Craniosynostoses; Acrocephalosyndactylia; Craniofacial Dysostosis; Skull
PubMed: 36821573
DOI: 10.1097/PRS.0000000000009926 -
The Journal of Craniofacial Surgery Jun 2023The Upton type III hand, which represents the most severe hand type among Apert syndrome patients, has been considered the least prevalent hand type. The objective of...
BACKGROUND
The Upton type III hand, which represents the most severe hand type among Apert syndrome patients, has been considered the least prevalent hand type. The objective of this study is to address type III Apert hand prevalence and describe treatment strategies that will result in a 5 digit hand.
METHODS
The authors retrospectively reviewed 15 years of Apert syndrome hand practice at our hospital. Demographic (patient sex and age at the time of the operation), surgical (eg, techniques used for webspace release, osteotomy, and various aspects of soft-tissue reconstruction), and outcome (perioperative and long-term complication and need for revision operation) data was verified through medical records, clinical photographs, radiographic images, and interviews with patients' families. Patients who had incomplete medical records and/or postoperative follow up <6 months in length were excluded from this study.
RESULTS
A total of 93 Apert patients [50 male (56.1%) and 43 female (43.9%)] were treated at our hospital from 2007 to 2021. Stratification of Apert hand severity using Upton's classification system identified 34 patients with type I hands (36.4%), 19 patients with type II hands (20.6%), and 40 patients with type III hands (43%). Of the 40 patients with type III hands a 5 digit hand was achieved for 35 patients (87%), with an average of 3.37 operations per patient.
CONCLUSIONS
The Upton type III hand is the most prevalent hand type among Apert syndrome patients. Following a three stage protocol, a surgical team can consistently achieve a 5 digit hand for the majority of Apert syndrome patients with type III hands.
Topics: Humans; Male; Female; Acrocephalosyndactylia; Retrospective Studies; Prevalence; Hand; Fingers
PubMed: 36730868
DOI: 10.1097/SCS.0000000000009107 -
The Journal of Craniofacial Surgery May 2023III.
III.
Topics: Humans; Child; Acrocephalosyndactylia; Skull; Mutation; Tomography, X-Ray Computed; Craniosynostoses
PubMed: 36730527
DOI: 10.1097/SCS.0000000000009126 -
The Journal of Craniofacial Surgery May 2023
Topics: Child; Humans; Infant; Acrocephalosyndactylia; Skull; Mutation; Craniosynostoses
PubMed: 36727961
DOI: 10.1097/SCS.0000000000009173