Mucin Production Correlates with Dual Expression of Epidermal Growth Factor Receptor and Its Ligand the Epidermal Growth Factor in Non-Small Cell Lung Cancer

Introduction: Mucoproduction plays an important role in the processes of tumor progression, invasion and metastasis. In non-small cell lung cancer (NSCLC), mucins hypersecretion has been associated with alterations in the epidermal growth factor receptor (EGFR) expression. However, the relation of mucins with EGFR in these tumors is not completely clarified. Aims: To evaluate the relation between mucoproduction, the expression of EGFR and its ligand the epidermal growth factor (EGF) in NSCLC samples. Materials and Methods: A number of 71 routinely processed formalin-fixed and paraffin-embedded archival samples with diagnosis of NSCLC were used. Mucoproduction was considered when periodic acid-Schiff reaction (PAS) positive and/or alcian blue positive substances were observed. The immunolocalization of EGFR and EGF molecules were detected by mean of immunohistochemical methods. Chi-square test was applied to compare two or three different parameters. In all cases, the criterion for statistical significance was p<0.05.