Stromal CEACAM1 expression regulates colorectal cancer metastasis.

Colorectal cancer metastasis to Ceacam1-/- livers is significantly impaired, compared with wild type livers, due to decreased endothelial cell survival, reduced tumor cell proliferation, diminished immune infiltration and altered chemokine expression. Ceacam1-/- myeloid-derived suppressor cells diminish metastatic burden, as confirmed by bone marrow transplantation and adoptive transfer experiments.