In addition, the newly expressed DDR2, in several cell lines of human cancer such as liver (HAK-1A and HAK-1B cells) (Maeyama et al., 2008), lung (A549 cells) (Walsh et al., 2011), and breast (MDA-MB-231, MCF-7, SK-BR3, and MDA-MB-468 cells) (Zhang et al., 2013; Ren et al., 2014), is phosphorylated upon interaction with type I collagen, suggesting that the induced receptor is physiologically active. Here, DDR2 is linked to cancer.