Processes and patterns: Insights on cranial covariation from an Apert syndrome mouse model.

BACKGROUND: Major cell-to-cell signaling pathways, such as the fibroblast growth factors and their four receptors (FGF/FGFR), are conserved across a variety of animal forms. FGF/FGFRs are necessary to produce several "vertebrate-specific" structures, including the vertebrate head. Here, we examine the effects of the FGFR2 S252W mutation associated with Apert syndrome on patterns of cranial integration. Our data comprise micro-computed tomography images of newborn mouse skulls, bred to express the Fgfr2 S252W mutation exclusively in either neural crest or mesoderm-derived tissues, and mice that express the Fgfr2 S252W mutation ubiquitously. RESULTS: Procrustes-based methods and partial least squares analysis were used to analyze craniofacial integration patterns. We found that deviations in the direction and degree of integrated shape change across the mouse models used in our study were potentially driven by the modular variation generated by differing expression of the Fgfr2 mutation in cranial tissues. CONCLUSIONS: Our overall results demonstrate that covariation patterns can be biased by the spatial distribution and magnitude of variation produced by underlying developmental-genetic mechanisms that often impact the phenotype in disproportionate ways.

Activation of FGFR2 Signaling Suppresses BRCA1 and Drives Triple-Negative Mammary Tumorigenesis That is Sensitive to Immunotherapy.

Fibroblast growth factor receptor 2 (FGFR2) is a membrane-spanning tyrosine kinase that mediates FGF signaling. Various FGFR2 alterations are detected in breast cancer, yet it remains unclear if activation of FGFR2 signaling initiates tumor formation. In an attempt to answer this question, a mouse model berrying an activation mutation of FGFR2 (FGFR2-S252W) in the mammary gland is generated. It is found that FGF/FGFR2 signaling drives the development of triple-negative breast cancer accompanied by epithelial-mesenchymal transition that is regulated by FGFR2-STAT3 signaling. It is demonstrated that FGFR2 suppresses BRCA1 via the ERK-YY1 axis and promotes tumor progression. BRCA1 knockout in the mammary gland of the FGFR2-S252W mice significantly accelerated tumorigenesis. It is also shown that FGFR2 positively regulates PD-L1 and that a combination of FGFR2 inhibition and immune checkpoint blockade kills cancer cells. These data suggest that the mouse models mimic human breast cancers and can be used to identify actionable therapeutic targets.

Análisis genotípico de 11 pacientes colombianos con Síndrome de Apert / Genotypic analysis of 11 Colombian Apert syndrome patients

Antecedentes. El síndrome de Apert (SA) es una de las craneosinostosis sindrómicas más severas que afecta el neuro y viscerocraneo y además presenta alteraciones multisistémicas con repercusiones en aspectos físicos (aspecto general y talla baja), sensoriales (hipoacusia y trastornos visuales), cognoscitivos (retardo mental o trastornos del aprendizaje) y de inclusión laboral (sindactilia severa en manos y pies). Su etiología es la mutación del receptor 2 del factor de crecimiento fibroblástico (FGFR2) y se hereda de forma autosómica dominante. Materiales y métodos. Se analizaron clínica y molecularmente 11 pacientes con sospecha de SA. Se realizó estudio mutacional mediante RFLP para el gen FGFR2. Resultados. Se confirmaron molecularmente los 11 pacientes con SA, cuyas edades oscilaron desde los 0 a 32 años. Todos los pacientes presentaron el fenotipo clásico. Se encontró un 63.6% de pacientes con la mutación S252W y 36.4% con P253R. Discusión. De los pacientes analizados, llamo la atención la presencia de talla baja y RM/RGD en algunos de ellos. Desde el punto de vista genotípico, las frecuencias mutacionales para S252W y P253R no mostraron diferencias con relación a lo reportado mundialmente. Aunque no se disponen de datos de la incidencia de esta patología a nivel local, este estudio podría ser el primer acercamiento para fines epidemiológicos en Colombia.

Background. Apert Syndrome (AS) is one of the most severe syndromic craniosynostosis affecting neuro and viscerocranium and presenting with multisystemic anomalies altering physical aspects (general looks and short stature), sensorineural aspects (deafness and visual problems), cognitive development (mental retardation or trouble learning) and work inclusion (severe syndactyly in hands and feet). Its aetiology relies on mutation of the Fibroblast Growth Factor Receptor type 2 (FGFR2) gene, inherited by an autosomal dominant path. Materials and methods. 11 patients with suspicion of AS were clinically evaluated and molecularly tested for mutations in FGFR2 by RFLP. Results. Patients with AS from 0 to 32 years old were analized for mutations in FGFR2 gene. All of them had the classical phenotype of the disease. 63.6% of the patients had the S252W mutation while 36.4% had the P253R mutation. Discussion. Of all patients enrolled in this study it is notwworthy that some of them had short stature, while others had mental retardation or global development delay. Mutational frequencies for S252W and P253R did not show difference according to what has been reported worldwide. Although there is no data about the incidence of this disease locally, this study could be a first approach to its epidemiology in Colombia.