DDR2 and cancer: Since CAFs are the predominant tumor stromal cell within the primary tumor environment that controls ECM production and arguably ECM remodeling (Bhowmick et al., 2004) and the Ddr2 gene and DDR2 protein expression is significantly upregulated in breast tumor CAFs during cancer progression (Corsa et al., 2016) (Gonzalez et al., 2017), we asked whether the action of DDR2 in breast tumor CAFs impacted CAF cellular functions that facilitate tumor progression and metastasis.