Title : Revolutionizing oral cancer diagnostics: High affinity DNA aptamers targeting immune associated biomarkers IFI6 and RSAD2
Abstract:
Background: Current advanced biomarker detection technologies provide significant advantages in overcoming variable specificity and sensitivity, batch variations, and cost issues in oral cancer diagnosis.
Objectives: This study aims to develop and characterize in silico DNA aptamers specifically targeting IFI6 and RSAD2 protein expression in Oral Squamous Cell Carcinoma (OSCC) tissues using aptahistochemical (AHC) techniques.
Methodology: In silico DNA aptamers targeting IFI6 and RSAD2 were designed, and their binding interactions were characterized through molecular docking and molecular dynamics simulations. Using AHC, IFI6, and RSAD2 protein expression in OSCC (n=23) and healthy (n=7) tissue samples was analysed through odds ratio analysis. The association between protein expression in cancer cells, immune cells, and histological tumour grades was also statistically analysed using the chi-square test.
Results: The IFI6 and RSAD2 DNA aptamers (ranging from 35-50 mers) demonstrated high affinity and specificity (-15.7 to -18.7 kcal/mol), strong hydrogen bond interactions(<4 Å), and high stability (RMSD <0.4 nm). AHC analyses revealed positive expression of IFI6 and RSAD2 in OSCC tissues, whilst absent in healthy tissues (odds-ratio = 705.000, p<0.05). Expression levels significantly increased with tumour-grade severity in cancer and immune cells (p<0.05).
Conclusion: Aptamer-based assay shows promising potential as an alternative diagnostic tool for OSCC, which can provide a cost-effective and accurate diagnosis, revolutionizing OSCC biomarker detection.
Keywords: in silico, DNA aptamers, IFI6, RSAD2, OSCC, Aptahistochemical

