MMP9 and bronchogenic carcinoma: Epidermal growth factor receptor (EGFR) and matrix-metalloproteinase 9 (MMP-9) are proteins linked to hyperproliferative diseases such as bronchial carcinoma (Gong et al. 2016; Pao et al. 2005) and are associated with the formation of neointimal hyperplasia in numerous studies (Newby 2005; Sanchez-Guerrero et al. 2013).