Together with the tyrosine-protein kinase SYK, enhances production of the cytokine CXCL8/IL-8 via the NFKB pathway and may thus have a role in the intestinal immune response. Interacts (via extracellular domain) with PTPRH (via extracellular domain); the interaction dephosphorylates CEACAM20. Interacts (phosphorylated form) with SYK (via SH2 domains); the interaction further enhances CEACAM20 phosphorylation. Colocalizes with PTPRH and CEACAM1 at the apical brush border of intestinal cells. Phosphorylated on tyrosine residues by SYK, SRC and FYN in vitro. Belongs to the immunoglobulin superfamily. CEA family.