Tooth abnormalities in congenital infiltrating lipomatosis of the face

PIK3CA mutations enhance the adipogenesis of ADSCs in facial infiltrating lipomatosis through TRPV1

Facial infiltrating lipomatosis (FIL) is a congenital disorder. The pathogenesis of FIL is associated with PIK3CA mutations, but the underlying mechanisms remain undetermined. We found that the adipose tissue in FIL demonstrated adipocytes hypertrophy and increased lipid accumulation. All adipose-derived mesenchymal stem cells from FIL (FIL-ADSCs) harbored PIK3CA mutations. Moreover, FIL-ADSCs exhibited a greater capacity for adipogenesis. Knockdown of PIK3CA resulted in a reduction in the adipogenic potential of FIL-ADSCs. Furthermore, WX390, a dual-target PI3K/mTOR inhibitor, was found to impede PIK3CA-mediated adipogenesis both in vivo and in vitro. RNA sequencing (RNA-seq) revealed that the expression of transient receptor potential vanilloid subtype 1 (TRPV1) was upregulated after PI3K pathway inhibition, and overexpression or activation of TRPV1 both inhibited adipogenesis. Our study showed that PIK3CA mutations promoted adipogenesis in FIL-ADSCs and this effect was achieved by suppressing TPRV1. Pathogenesis experiments suggested that WX390 may serve as an agent for the treatment of FIL.

Congenital Infiltrating Lipomatosis of Face-Induced Temporomandibular Joint Ankylosis

Temporomandibular joint ankylosis (TMJA) secondary to congenital infiltrating lipomatosis of the face (CILF) is an exceptionally uncommon condition which is characterized by the involvement of unilateral facial soft tissues and bones. In some cases, the extensive exophytic bony growth in the temporomandibular joint region often extends toward the skull base and lies near adjacent vital structures. Only very few cases of TMJA associated with CILF have been reported in the literature. The authors report a case of a 36-year-old female with right TMJA secondary to CILF. The bony overgrowth in the right temporomandibular joint region was arising from a deformed right mandibular condyle, extending towards the ipsilateral temporal bone, greater wing of the sphenoid, skull base, and approaching the lateral limit of foramen ovale, and foramen spinosum. To prevent any damage to the skull base and adjacent vital structures and to achieve adequate mouth opening, the authors have performed a unique technique of subankylotic osteotomy for the release of TMJA, instead of conventional gap arthroplasty.

Delineation of the phenotypes and genotypes of facial infiltrating lipomatosis associated with PIK3CA mutations

BACKGROUND

Facial infiltrating lipomatosis (FIL) is a rare congenital disorder characterized by unilateral facial swelling, for which surgery is the prevailing therapeutic option. Several studies have shown that the development of FIL is closely associated with PIK3CA mutations. This study aimed to further identify rare clinical features and underlying molecular variants in patients with FIL.

RESULTS

Eighteen patients were included in this study, and all patients presented with infiltrating adipose tissues confirmed by magnetic resonance imaging. Macrodactyly, polydactyly, hemimegalencephaly and hemihyperplasia were also observed in patients with FIL. In total, eight different PIK3CA mutations were detected in tissues obtained from sixteen patients, including the missense mutations p.His1047Arg (n = 4), p.Cys420Arg (n = 2), p.Glu453Lys (n = 2), p.Glu542Lys (n = 2), p.Glu418Lys (n = 1), p.Glu545Lys (n = 1), and p.His1047Tyr (n = 1) and the deletion mutation p.Glu110del (n = 3). Furthermore, the GNAQ mutation p.Arg183Gln was detected in the epidermal nevus tissue of one patient. Imaging revealed that several patients carrying hotspot mutations had more severe adipose infiltration and skeletal deformities.

CONCLUSIONS

The abundant clinical presentations and genetic profiles of FIL make it difficult to treat. PIK3CA mutations drive the pathogenesis of FIL, and PIK3CA hotspot mutations may lead to more extensive infiltration of lipomatosis. Understanding the molecular variant profile of FIL will facilitate the application of novel PI3K-targeted inhibitors.

Congenital infiltrating lipomatosis of the face: A subtype of hemifacial hyperplasia

OBJECTIVE

To investigate the clinical, imaging and pathological features of congenital infiltrating lipomatosis of the face (CILF) and to discuss whether it is a subtype of hemifacial hyperplasia (HH).

METHODS

Sixteen patients diagnosed with CILF were included in this study. All patients had undergone panoramic radiography and spiral CT examinations. Thirteen patients received biopsy, surgery treatment and pathological examination. The clinical documentation and imaging data were retrospectively reviewed.

RESULTS

The cheeks (14/16), parotid glands (12/16), tongues (9/16), masticatory muscles (8/16) and the lips (7/16) were the most frequently affected soft tissue organs. The maxilla (14/16), zygoma (13/16), mandible (13/16) were involved among the maxillofacial bones. Dental malformations included macrodontia (8/16), poor formation of the roots (7/16), accelerated tooth germ development or premature eruption of permanent teeth (7/16) and missing of the permanent teeth (4/16). All malformations were restricted to one side of the face and did not trespass the middle line. Pathologically, CILF was featured by the diffuse infiltration of redundant mature adipose tissue into the tissue of the affected organ.

CONCLUSION

CILF is a congenital developmental facial malformation characterized by infiltration of nonencapsulated, mature adipose tissue, resulting in facial soft and hard tissue hypertrophy and dental malformations in hemifacial structures. CILF could be considered as a subtype of HH.

[Congenital infiltrating lipomatosis of face with seizures: a case report]

Congenital infiltrating lipomatosis of the face is a rare disorder resulting from overgrowth of adipose tissues. This condition presents gradually with swelling along with age, hypertrophy of adjacent bones, and tooth abnormalities. This study reports a case of congenital infiltrating lipomatosis of face with seizures and reviews relevant literature on the etiology, clinical symptom, diagnosis, and treatment of this condition.

Congenital Infiltrating Lipomatosis of the Face: Case Report and Literature Review

Rationale

Congenital infiltrating lipomatosis of the face (CILF) is a rare disorder characterized by collections of nonencapsulated mature lipocytes that infiltrate surrounding tissues. In this article, we would report a new case of CILF, which may be one of the first few cases reported in China.

Patient Concerns

An 8-year-old boy presented with a hyperplasia of subcutaneous tissue of his left face, which had been gradually progressing since birth, resulting in a marked facial asymmetry. Then he underwent an operation of resection of the subcutaneous mass, and the postoperative pathological analysis reported a mature adipose tissue.

Diagnoses and Outcomes

The diagnosis of CILF was finally made according to a comprehensive consideration of the patient's situation. We then searched different databases for studies that had investigated CILF, reviewed those literatures, and gave our summaries for such a rare disease.

Lessons

Congenital infiltrating lipomatosis of the face is an extremely rare disease. There is so much unknown about it, and the gradual progress and recurrence make it even harder to cure. Besides, the psychological impact on such patients must be considered. Thus, a proper collection and analysis of the reports of such a disease are very important.

[The dental collection Hyacinthe Brabant: A pedagogic and scientific tool]

Among the numerous specimens preciously preserved in the Anatomical and Embryological Museum of ULB, there lies also a dental collection assembled by Professor Hyacinthe Brabant. This collection, previously unlabelled, shows several dental anomalies and pathologies as well as tumours. The objective of our study was to conduct an inventory of this collection and to set up an electronic iconographic tool through the Iconography website of ULB. A descriptive study was carried out and it was based on the analysis of 125 models and 90 extracted human teeth. The inspection of the models showed some non-odontological tumours as well as multiple dental anomalies. The extracted teeth showed generalised, coronal or radicular anomalies. The conducted inventory allowed us to classify and label the specimens and therefore to showcase this dental collection which is unique owing to its rich content and didactic display. Finally, the iconographic site will be a useful tool to raise awareness about several dental pathologies and anomalies among students and young practionners.