Reduced expression of mir15a in the blood of patients with oral squamous cell carcinoma is associated with tumor staging

MicroRNAs (miRNAs) mirl 5a 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 \u27I he 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 nfirl5a 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 stagin