THE STUDY OF PROGNOSTIC VALUE OF microRNAs (miR-10b AND -155) AND CDKN2A/P16INK4A IN ORAL SQUAMOUS CELL CARCINOMA.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most common types of cancer worldwide. Disco- vering novel prognostic markers for OSCC can improve treatment outcomes by allowing for more effective therapy strategies.

AIM: To identify the prognostic value of CDKN2A (p16INK4a) and miRNAs involved in its regulation as markers of OSCC.

MATERIALS AND METHODS: The work is based on the results of the examination and treatment of 70 patients with stage II-IV OSCC. miR-10b, -155, and CDKN2A mRNA expression in tumor samples was ana- lyzed by real-time reverse transcription polymerase chain reaction. The expression of p16INK4a and Ki-67 proteins was determined immunohistochemically.

RESULTS: No association of CDKN2A mRNA and p16INK4a protein with Ki-67 expression in tumor tissue and clinical pathological parameters of OSCC patients was found. Most of the p16INK4a-positive cases were characterized by a high Ki-67 expression. We found a strong correlation of the studied miRNAs expression levels with lymph node metastasis (r = 0.56 for miR-10b and r = 0.59 for miR-155). Also, there was no difference in miR-10b and -155 expression between p16INK4a+ and p16INK4a- samples. The association of both miRNAs with lymph node metastases was not affected by p16INK4a status.

CONCLUSIONS: The results indicate the relationship between miR-10b and -155 and the presence of lymph node metastases in OSCC patients, so these miRNAs can be considered as prognostic markers of the disease.