Higher levels of GREM1 also associate with poorer prognosis in patients with colorectal (Davis et al. 2015; Dutton et al. 2019a, b), gastric (Honma et al. 2018), and breast cancer (Neckmann et al. 2019) suggesting a role for GREM1 as a tumor promotor. This evidence concerns the gene GREM1 and breast cancer.