Carcinoembryonic antigen-related cell adhesion molecule 1 (
CEACAM1), a cell-
cell adhesion molecule, has been revealed to perform an important role in
tumor progression. Although there are a number of studies on
CEACAM1 in patients with
breast cancer, there is limited information on the roles of
CEACAM1 in
breast cancer metastasis. The present study aimed to identify whether
CEACAM1 is involved in
breast cancer development and to investigate the underlying mechanisms. First, the expression of
CEACAM1 was observed in patients with
breast cancer, and the association between
CEACAM1 expression levels and migration and invasion of
breast cancer cells was analyzed. As there are 12
isoforms of
CEACAM1, of which CEACAM1-4S dominates in the human breast epithelium, subsequent study focused on CEACAM1-4S as a representative of all the
isoforms. Results of the present study demonstrated that CEACAM1-4S suppresses
breast cancer cell invasion and migration in a manner that is dependent on the balance between
matrix metalloproteinase 2/
tissue inhibitor of metalloproteinase 2 and E-/
N-cadherin expression. In addition, CEACAM1-4S was likely to cause reversal of epithelial-mesenchymal transition of
breast cancer cells through repressing Smad2 and signal transducer and phosphorylation of activator of transcription 3. In conclusion, the present study demonstrated that CEACAM1-4S performs an inhibitory role in
breast cancer metastasis, and restoring CEACAM1-4S expression may provide a novel strategy for
therapy of patients with metastatic
breast cancer.