MicroRNA Expression Profiling of Oral Carcinoma Identifies New Markers of Tumor Progression

TLDR

Oral squamous cell carcinoma has a poor prognosis largely due to metastasis, and identifying reliable prognostic markers—such as dysregulated microRNAs that control proliferation, differentiation, and apoptosis—could improve clinical outcomes. The study aimed to delineate the role of miRNAs in OSCC by profiling their expression in tumors with and without lymph node metastasis and to assess their potential for improved classification and patient care. Expression profiles of 15 OSCC samples (8 non‑metastatic and 7 metastatic) were obtained via microarray analysis. Thirteen miRNAs were overexpressed and six were underexpressed in OSCC, with reduced levels of miR‑155, let‑7i, and miR‑146a specifically associated with metastatic progression.

Abstract

Oral squamous cell carcinoma, the most frequently occurring malignant head and neck tumour, generally exhibits poor prognosis and metastases are the main cause of death. The discovery of reliable prognostic indicators of tumour progression could greatly improve clinical practice. MicroRNAs are involved in the regulation of basic cellular processes such as cell proliferation, differentiation, and apoptosis. Since miRNAs have been shown to be abnormally expressed in different tumours their importance as potential cancer prognostic indicators is increasing. To define the role of miRNA in OSCC tumours we investigated the expression profile of 15 OSCC (8 without metastasis and 7 with lymph node metastasis) using microarray analysis. Thirteen miRNA were significantly overexpressed (miR-489, miR-129, miR-23a, miR-214, miR-23b, miR-92, miR-25, miR-210, miR-212, miR-515, miR-146b, miR-21, miR-338) and 6 miRNA were underexpressed (miR-520h, miR-197, miR-378, miR-135b, miR-224, miR-34a) in oral tumours. Underexpression of mir-155, let-7i, mir-146a was found to characterize progression to metastastatic tumours. Further investigations will elucidate whether differentially expressed miRNAs will help to better classify OSCCs, thus improving diagnoses and patient care.