Investigation of Pepsin in Laryngeal Squamous Cell Carcinoma Specimens

Abstract

Objective: Squamous cell carcinoma (SCC) composes 95% of the carcinoma of the larynx. One of the factor recognized in the past two decades as increasing the risk of SCC is laryngopharyngeal reflux (LPR). The role and mechanism of LPR in laryngeal cancer remain unclear. The aim of this study was to assess the presence of pepsin in laryngeal formalin-fixed, paraffin-embedded (FFPE) squamous cell carcinoma (SCC) specimens in order to test the hypothesis that LPR plays a role in the development of laryngeal SCC. Method: A total of 29 pathology specimens of advanced-stage laryngeal cancer patients who had undergone total laryngectomy were evaluated. The specimens were confirmed histopathologically as SCC and maintained in paraffin blocks in the pathology department. The western blot (WB) or the enzyme-linked immunosorbent assay (ELISA) analyses were used to measure pepsin enzyme levels. Results: According to the WB and ELISA analyses, there was no presence of the pepsin enzyme in any of the 29 formalin-fixed, paraffin-embedded (FFPE) laryngeal SCC specimens. However, pepsin was detected with both the WB and the ELISA tests in positive controls and fresh rat stomach specimen. Conclusion: Pepsin was not present in any of the malignant laryngeal squamous cell carcinoma specimens in this study. Relationship between LPR and laryngeal SCC still remains unclear and further studies are needed to verify the role of pepsin and LPR in laryngeal SCC.