FN1 and breast cancer: MatrigelTM (Rizvi et al., 2011; Xu et al., 2011), gelatin (Zhao et al., 2014; Dai et al., 2016), or alginate (Zhao et al., 2014; Dai et al., 2016) are commonly used for 3DBP models, but a gap exists in reported 3DBP employing important breast cancer-associated ECM proteins such as collagens type I, III, fibronectin, laminin, other glycoproteins, and proteoglycans.