DDR1 and cancer: Whitney R et al. reported that a novel small molecule inhibitor (WRG-28) could inhibit tumor invasion and migration and metastatic breast tumor cell colonization in the lungs by targeting DDR2 (Grither and Longmore, 2018 Ru Dong et al. demonstrated that compound 6c was a potential DDR1 inhibitor deserving further investigation for cancer treatment (Dong et al., 2021).