Application of proximity ligation assays to identify potential plasma biomarkers in oral cavity cancer patients: A case control study

Abstract

BACKGROUND: Practical cancer biomarkers for oral cavity cancer are currently in limited use. OBJECTIVE: We aimed to investigate the differences in soluble E-cadherin between patients with oral cavity cancer and matched healthy participants via Proximity Ligation Assay (PLA). METHODS: Samples were taken from both patients diagnosed with oral cavity cancer, as well as non-cancerous participants. PLA was used to detect soluble E-cadherin and Cycle threshold (Ct) values derived from qPCR in order to calculate the number of starting amplicons. RESULTS: In total, 74 patients with oral cavity cancer and 55 matched non-cancerous participants were included for final analysis. The Ct value of E-cadherin was found to be lower in oral cavity cancer patients when compared with that of the matched non-cancerous participants (20.72 ± 0.39 versus 21.27 ± 0.45, P< 0.001). Using a Ct value of 20.9 as a cut-off point, the sensitivity and specificity of discriminating patients with oral cavity cancer from the healthy controls was 63.5% and 87.3%, respectively. CONCLUSION: Plasma soluble E-cadherin levels were significantly higher in patients with oral cavity cancer when compared with those from the matched non-cancerous participants.