S100 Proteins as Biomarkers in Risk Estimations for Malignant Transformation in Oral Lesions.

Oncologic relevant members of S100 proteins are described as promising biomarkers in molecular pathology for risk estimation in oral neoplasia exhibiting different stages of malignancy: gingiva as healthy tissue, irritation fibroma as benign, leukoplakia as precancerous, and oral squamous cell carcinoma as malignant entity. Gene expression levels of S100A4 (metastasin), S100A7 (psoriasin), S100A8 (calgranulin A), and S100A9 (calgranulin B) were analyzed using quantitative RT-PCR. In addition, immunohistochemistry-based microscopy was used to examine cellular localization and distribution of these biomarkers in tissue sections. The results indicate that S100 proteins represent promising biomarkers for early-stage diagnosis in oral lesions. The inclusion of expression profiles and ratios for each entity even improves their diagnostic validity.