NUMERO: #20260264

Título: CTNNB1 MOLECULAR INVESTIGATION IN ODONTOMA AND IN CALCIFYING ODONTOGENIC CYST ASSOCIATED WITH ODONTOMA

Nome do Apresentador: Flávia Martins Vasconcelos FILIÚ

Categoria do Trabalho: Pôster - Investigação Original (IO)

Área Temática: Patologia Oral

Resumo: Objective: Calcifying odontogenic cysts (COC) associated with odontomas are
among the most common hybrid odontogenic lesions. COC harbour CTNNB1
mutations and beta-catenin immunoexpression. It is unclear if odontomas harbour
CTNNB1 mutations, but aberrant WNT/beta-catenin activation drives odontoma-like
structures in murine models. COC associated with odontoma (COCawOd) have not
been previously molecularly investigated. Therefore, we aimed to assess CTNNB1
mutations in odontoma and COCawOd, and the immunoexpression of beta-catenin
in the latter. Study design: Four FFPE cases of odontoma and 10 of COCawOd
were included. COCawOd were manually microdissected to separate both areas.
CTNNB1 exon 3 was Sanger sequenced. Beta-catenin immunohistochemistry was
performed in COCawOd. Results: The odontoma cases were wild-type for the
CTNNB1 mutations. In COCawOd, CTNNB1 mutations (p.Ser33Cys) were detected
in 2/7 COC areas, and in none of the 5 odontoma areas evaluated. Focal nuclear
beta-catenin immunoexpression was observed in the epithelial areas of odontoma
(2/7) and COC (4/6) components, and cytoplasmic staining in virtually all cases.
Conclusion: CTNNB1 mutations were identified exclusively in the COC component
of COCawOd, whereas no mutations were detected in either in the odontoma areas
of COCawOd or in the odontoma samples. Both areas of COCawOd showed beta-
catenin immunoexpression. Support: CAPES/PROEX; FAPEMIG; CNPq.

Autor 1:  Flávia Martins Vasconcelos FILIÚ

E-mail 1:  [email protected]

Autor 2:   Victor Coutinho BASTOS

E-mail 2:  [email protected]

Autor 3 :  Bruna Pizziolo COURA

E-mail 3:  [email protected]

Autor 4:  Vanessa Fátima BERNARDES

E-mail 4:  [email protected]

Autor 5:  Fabrício PASSADOR-SANTOS

E-mail 5:  [email protected]

Autor 6:  Felipe Paiva FONSECA

E-mail 6:  [email protected]

Autor 7:  Carolina Cavaliéri GOMES

E-mail 7:  [email protected]