title: Reduced expression of mir15a in the blood of patients with oral squamous cell carcinoma is associated with tumor staging.
abstract: MicroRNAs (miRNAs) mir15a and let7a are important regulators of bcl-2, ras and c-myc proteins. Considering that these miRNAs are commonly altered in many human cancers and that these proteins are reported to be altered in oral squamous cell carcinoma (OSCC), we investigated them in a set of OSCC cases. The miRNAs as well as the proteins were evaluated in the tumor and blood of 20 patients by real-time quantitative PCR and immunohistochemistry, respectively. The expression of mir15a and bcl-2 proteins in the tumors was not associated with each other or with tumor staging. On the other hand, we found reduced expression of this miRNA in the blood of patients with an advanced stage of OSCC and with lymph node metastasis. The expression of let7a in the tumor and blood was not associated with tumor size, lymph node metastasis, tumor staging and immunoexpression of ras and c-myc proteins. In conclusion, the present study shows that reduced expression of mir15a is associated with OSCC staging.
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry.
authors.forename: João Artur
authors.initials: JA
authors.lastname: Ricieri Brito
authors.forename: Carolina Cavaliéri
authors.initials: CC
authors.lastname: Gomes
authors.forename: Flávio Juliano Garcia
authors.initials: FJ
authors.lastname: Santos Pimenta
authors.forename: Alvimar Afonso
authors.initials: AA
authors.lastname: Barbosa
authors.forename: Marco Antônio Máximo
authors.initials: MA
authors.lastname: Prado
authors.forename: Vânia Ferreira
authors.initials: VF
authors.lastname: Prado
authors.forename: Marcus Vinícius
authors.initials: MV
authors.lastname: Gomez
authors.forename: Ricardo Santiago
authors.initials: RS
authors.lastname: Gomez
keywords: let7a; microRNA; mir15a; oral cancer