Carcinoembryonic antigen enhances metastatic potential of human colorectal carcinoma
R. B. Hostetter, D. E. Campbell, K. F. Chi, S. Kerckhoff, K. R. Cleary, S. Ullrich, P. Thomas and J. M. Jessup
Department of Surgery, University of Texas M.D. Anderson Cancer Center, Houston.
Patients with human colorectal carcinoma have a poor prognosis when serum
carcinoembryonic antigen level exceeds 5 ng/mL. The hypothesis that
carcinoembryonic antigen enhances metastasis by promoting the attachment of
tumor cells to Kupffer cells and hepatocytes was tested in an experimental
metastasis model in which colorectal carcinoma cells were injected into the
spleens of BALB/c athymic nude mice and liver colonies counted 5 weeks
later. Pretreatment with systemic injections of carcinoembryonic antigen
significantly increased the metastatic potential of a poorly metastatic
colorectal carcinoma cell line KM-12c, but did not induce the nonmetastatic
colorectal carcinoma cell line HC 2998 to produce metastases, nor did
carcinoembryonic antigen make the highly metastatic colorectal carcinoma
cell line mHC 1410 more metastatic. Carcinoembryonic antigen did not
stimulate proliferation of colorectal carcinoma but appeared to be a
cofactor for metastasis possibly as an adhesion factor.