c. 595-596 insC of FOXC2 underlies lymphedema, distichiasis, ptosis, ankyloglossia, and Robin sequence in a Thai patient

Genetic Mutations Associated with Pierre Robin Syndrome/Sequence: A Systematic Review

Pierre Robin syndrome/sequence (PRS) is associated with a triad of symptoms that includes micrognathia, cleft palate, and glossoptosis that may lead to respiratory obstruction. The syndrome occurs in 2 forms: nonsyndromic PRS (nsPRS), and PRS associated with other syndromes (sPRS). Studies have shown varying genetic mutations associated with both nsPRS and sPRS. The present systematic review aims to provide a comprehensive collection of published literature reporting genetic mutations in PRS. Web of Science, PubMed, and Scopus were searched using the keywords: "Pierre Robin syndrome/sequence AND gene mutation." The search resulted in 208 articles, of which 93 were excluded as they were duplicates/irrelevant. The full-text assessment led to the further exclusion of 76 articles. From the remaining 39 articles included in the review, details of 324 cases were extracted. 56% of the cases were sPRS, and 22% of the cases were associated with other malformations and the remaining were nsPRS. Genetic mutations were noted in 30.9% of the 300 cases. Based on the review, SOX9 was found to be the most common gene associated with both nsPRS and sPRS. The gene mutation in sPRS was specific to the associated syndrome. Due to the lack of original studies, a quantitative analysis was not possible. Thus, future studies must focus on conducting large-scale cohort studies. Along with generating data on genetic mutation, future studies must also conduct pedigree analysis to assess potential familial inheritance, which in turn could provide valuable insights into the etiopathogenesis of PRS.

Clinical presentation and management of congenital ptosis

Congenital ptosis is a rare condition characterized by lower positioning of the upper eyelid that is present at birth and is a clinical condition that is persistent if not treated. It may be unilateral or bilateral and may be associated with other ocular disorders or systemic conditions, including Marcus Gunn, Horner, and Duane syndromes. It is a benign condition but causes functional, cosmetic, and psychological problems in children. However, not all patients need to undergo surgery, and usually only patients at risk of amblyopia need a prompt surgical correction, while in other cases, surgery can be postponed. The grade of ptosis, the eyelid function, and the amblyopic risk are the parameters that affect the ophthalmologist’s decision on timing of surgery and the surgical technique to be used. In fact, there are several types of surgical techniques to correct a congenital ptosis, although very often more than one is needed to obtain an acceptable result. This paper reviews the causes of congenital ptosis and associated diseases. Particular emphasis is given to surgical management and different procedures available to correct the upper eyelid anomaly and avoid permanent damage to visual function.

Early Mandibular Distraction to Relieve Robin Severe Airway Obstruction in Two Siblings with Lymphedema-Distichiasis Syndrome

Although micrognathia and cleft palate have been reported in patients with Lymphedema-distichiasis syndrome (LDS), the classic Robin sequence with glossoptosis and airway obstruction has not been previously described in patients with genetically confirmed LDS. Here we report on two female siblings with LDS confirmed by a FOXC2 mutation who presented at birth with severe airway obstruction related to Robin sequence. Respiratory obstruction was successfully managed by early distraction osteogenesis. Our report highlights the unusual occurrence of Robin sequence in LDS patients and advises distraction osteogenesis to resolve breathing problems in LDS patients who present with Robin related severe airway obstruction.

Identification of novel craniofacial regulatory domains located far upstream of SOX9 and disrupted in Pierre Robin sequence

Mutations in the coding sequence of SOX9 cause campomelic dysplasia (CD), a disorder of skeletal development associated with 46,XY disorders of sex development (DSDs). Translocations, deletions, and duplications within a ∼2 Mb region upstream of SOX9 can recapitulate the CD-DSD phenotype fully or partially, suggesting the existence of an unusually large cis-regulatory control region. Pierre Robin sequence (PRS) is a craniofacial disorder that is frequently an endophenotype of CD and a locus for isolated PRS at ∼1.2-1.5 Mb upstream of SOX9 has been previously reported. The craniofacial regulatory potential within this locus, and within the greater genomic domain surrounding SOX9, remains poorly defined. We report two novel deletions upstream of SOX9 in families with PRS, allowing refinement of the regions harboring candidate craniofacial regulatory elements. In parallel, ChIP-Seq for p300 binding sites in mouse craniofacial tissue led to the identification of several novel craniofacial enhancers at the SOX9 locus, which were validated in transgenic reporter mice and zebrafish. Notably, some of the functionally validated elements fall within the PRS deletions. These studies suggest that multiple noncoding elements contribute to the craniofacial regulation of SOX9 expression, and that their disruption results in PRS.

FOXC2 is a novel prognostic factor in human esophageal squamous cell carcinoma

BACKGROUND

FOXC2 has been implicated in cancer progression through its induction of epithelial-to-mesenchymal transition. We analyzed the clinical significance of FOXC2 in esophageal cancer cases, in which early distant metastasis or invasion to nearby organs is an obstacle to treatment.

METHODS

Quantitative reverse transcriptase-polymerase chain reaction was used to evaluate FOXC2 mRNA expression in 70 esophageal cancer cases to determine the clinicopathologic significance of FOXC2 expression. Furthermore, we examined associations between FOXC2 expression and matrix metalloproteinases 2 (MMP2) and matrix metalloproteinases 9 (MMP9). We also performed in vitro invasion and migration assays for FOXC2-suppressed esophageal cancer cells.

RESULTS

In clinicopathologic analysis, the high-FOXC2 expression group showed a higher incidence of advanced tumor stage, lymph node metastasis, and lymphatic invasion than the low-FOXC2 expression group (P < 0.05). In particular, tumor stage exhibited the most remarkable difference (P < 0.0001). Expression of MMP2 and MMP9 was far higher in the high-FOXC2 expression group. Furthermore, the high-FOXC2 expression group had a significantly poorer prognosis than did the low expression group (P = 0.006). Multivariate analysis indicated that high FOXC2 expression was an independent prognostic factor for survival. Suppression of FOXC2 expression altered the invasive and the migratory ability of esophageal cancer cells in vitro.

CONCLUSIONS

Our findings suggest that FOXC2 could be an important prognostic indicator for esophageal cancer patients. FOXC2 is directly involved in cancer progression and is associated with poor prognosis in esophageal cancer cases.