GREM1 and colorectal carcinoma: Using a series of in silico and in situ methodologies, we demonstrate that GREM1 gene expression is significantly higher (p< 0.0001) in CRC consensus molecular subtype 4 (CMS4), compared to the other CMS subtypes and correlates (p< 0.0001) with levels of cancer-associated fibroblasts (CAFs) within the CRC tumour microenvironment (TME).