CEACAM5 is upregulated in several human cancers, including those of the gastrointestinal, respiratory, and genitourinary systems and the breast, and is involved in proliferation, migration, metastasis, and inhibition of apoptosis that occurs in the absence of interactions with the extracellular matrix (anoikis; refs. 3, 4). This evidence concerns the gene CEACAM5 and cancer.