Expression of caveolin-1 in tooth germ, ameloblastoma and ameloblastic carcinoma / Expresión de caveolina-1 en germen dental ameloblastoma y carcinoma ameloblástico

ABSTRACT

Background: The caveolin-1 protein (structural component of membrane caveolae) plays important roles in sev-eral biological functions, such as endocytosis, cell adhesion, and cell signaling. However, this protein has been as-sociated with mechanisms of tumorigenesis in several neoplasms. The expression patterns and roles of caveolin-1in the oral epithelium and in embryonic and odontogenic tumor tissues are still unclear.Material and Methods: The expression of caveolin-1 was evaluated in samples of the normal gingival epithelium(n=7), human tooth germ (TG) (n=12), ameloblastoma (AM) (n=83), and ameloblastic carcinoma (AC) (n=9) byimmunohistochemistry. Additionally, AM samples were analyzed by qRT-PCR and Western blot.Results: Most TG (91.7%), AM (73.5%) and AC (100%) samples showed diverse patterns of immunohistochemicalpositivity for caveolin-1, while only one gingival sample was positive. The transcript levels of cav-1 were signifi-cantly upregulated by 14.9-fold in AM tissue (P = 0.0014) compared to those in normal gingival epithelial tissue,as shown by qRT-PCR. Presence of caveolin-1 protein was confirmed by Western blot analysis. The caveolin-1immunoexpression patterns throughout the stages of TG show its importance during odontogenesis.Conclusions: The overexpression of caveolin-1 in AM and AC compared to its expression in normal gingivalepithelium (adult tissue) suggests a possible role of caveolin-1 in protumoral events, but due to the similar immu-noexpression observed in AM and AC, caveolin-1 may not necessarily participate in the malignant transformationprocess. However, future studies are needed to clarify and confirm these hypotheses.(AU)