Hybridization was clearly detected throughout the cytoplasm of 7 out of 15 adenomas and 13 out of 15 carcinomas with the CEA cDNA probe, and in 6 out of 15 adenomas and 10 out of 15 carcinomas with the NCA cDNA probe.
However, the two other markers carcinoembryonic antigen (CEA) and carbohydrate antigen CA19-9, showed no significant difference between superficial colorectal adenocarcinoma and adenoma.
CEA.Tg mice were crossed with mice bearing a mutation in the Apc gene (MIN mice), and the CEA.Tg/MIN progeny developed multiple intestinal neoplasms, which overexpress CEA to levels that are reminiscent of those reported for tubulovillous intestinal adenomas from patients.
CEA mRNA was detected together with NCA mRNA in nine cultured cell lines, with the exception of the lung carcinoma A549 cell line, and in 19 colon tissue specimens, including carcinomas, adjacent noninvaded tissues and adenomas.
Among patients with CRN, the proportions of elevated CEA/CA 19-9 levels were significantly higher in patients with ACRN than in those with non-ACRN, and these levels were correlated with larger lesion size and multiplicity of adenomas.