In CRC, the expanding liver metastatic tumour is rich in TAMs (primarily M2 macrophages) [157, 165], which are recruited through the CCL2/CCR2 chemokine axis to form an immunosuppressive microenvironment [166], which is regulated by the expression of TCF4 in CRC cells to promote LM [167]. Here, TCF4 is linked to colorectal carcinoma.