CXCL13 and lung cancer: CXCL13 expression can be induced in various airway epithelial cells, pneumocytes, macrophages, and pulmonary reticular cells/fibroblasts in diverse inflammatory conditions such as allergic airway inflammation, environmental pollutant-induced lung cancer, and bacterial and viral infection (Baay-Guzman et al. 2012; Wang et al. 2015; Bracke et al. 2013; Denton et al. 2019; Frija-Masson et al. 2017).