This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Shi, Z. R. Articles by Kim, Y. S. Search for Related Content PubMed PubMed Citation Articles by Shi, Z. R. Articles by Kim, Y. S.

Subcellular Distribution, Synthesis, and Release of Carcinoembryonic Antigen in Cultured Human Colon Adenocarcinoma Cell Lines¹

Gastrointestinal Research Laboratory, Veterans Administration Medical Center, San Francisco 94121, and the Department of Medicine, University of California School of Medicine, San Francisco, 94143, California

The content of carcinoembryonic antigen (CEA) and its subcellular distribution were studied in nine human colon carcinoma cell lines. A great variation in CEA content was found among different colon cancer cell lines. Well-differentiated colon cancer cell lines (LS174T and SKCO-1) contained the highest CEA activity which was 35 to 60 times greater than that of less well-differentiated cells (SW620, SW480, and HRT18). More than 80% of the CEA was associated with the cell membrane in all nine cell lines. With increasing cell density, the CEA content per cell was found to increase in SW1116, HCT8, and HCT48 cells, while no change was observed in SW620, HRT18, and HT29 cells. In SW480, LS174T, and SKCO-1 cells, CEA content actually decreased with increasing cell density. Investigation of the synthesis of CEA in cells and its release into the medium over an 8-day period showed that the rate of CEA synthesis at maximum cell density for LS174T and SKCO-1 cells decreased to 15 and 50% of that at low cell density, respectively. In contrast, the rate of CEA release into medium by these two cell lines was higher at maximum than at low cell density. For HCT48 cells, the increased rate of CEA synthesis with increasing cell density markedly elevated cellular CEA levels. These observations were confirmed by studying the rate of incorporation of N-acetyl[³H]-glucosamine into cellular CEA in LS174T and HCT48 cell lines. The rate of incorporation of radioactivity into CEA was greater during the exponential phase of growth than during the stationary phase for LS174T, while the opposite was observed with HCT48 cells.

This study indicated that there is a great variation in CEA content among different human colon cancer cell lines and that it is associated predominantly with the membrane fraction. The rate of synthesis and release of CEA also varied among different cell lines. The growth phase had a varied effect on the CEA content, the rate of synthesis, and the release of CEA in these human colon cancer cell lines.

¹ Supported by USPHS Grant CA-14905 from the National Cancer Institute through the National Large Bowel Cancer Project and the Veterans Administration Medical Research Service.

² To whom requests for reprints should be addressed, at Gastrointestinal Research Laboratory (151M2), Veterans Administration Medical Center, 4150 Clement Street, San Francisco, Calif. 94121.

Received 3/ 8/82. Accepted 5/31/83.

This article has been cited by other articles:

				C. P. Graff, K. Chester, R. Begent, and K.D. Wittrup Directed evolution of an anti-carcinoembryonic antigen scFv with a 4-day monovalent dissociation half-time at 37{degrees}C Protein Eng. Des. Sel., April 1, 2004; 17(4): 293 - 304. [Abstract] [Full Text] [PDF]

				C. P. Graff and K. D. Wittrup Theoretical Analysis of Antibody Targeting of Tumor Spheroids: Importance of Dosage for Penetration, and Affinity for Retention Cancer Res., March 15, 2003; 63(6): 1288 - 1296. [Abstract] [Full Text] [PDF]

				D. A. Berk, F. Yuan, M. Leunig, and R. K. Jain Direct in vivo measurement of targeted binding in a human tumor xenograft PNAS, March 4, 1997; 94(5): 1785 - 1790. [Abstract] [Full Text] [PDF]