3'-RACE analysis of a primary adenoma with an apparently normal karyotype revealed an HMGIC fusion transcript containing ectopic sequences derived from the human NFIB gene, previously mapped to chromosome band 9p24.1.
RNase protection, rapid amplification of 5'-cDNA ends (5'-RACE), and reverse transcription-PCR analyses of five adenomas with a normal karyotype revealed fusion transcripts in three tumors.
There was very low or no expression of AMACR protein in normal colon, but AMACR was highly expressed in 76 and 75% of well and moderately differentiated colon carcinomas, respectively, and in 79% of adenomas.
Our results indicate that as well as being an additional diagnostic tool, altered AMACR expression in gastric adenomas and intestinal-type carcinomas suggests that AMACR may be involved early in the development of intestinal-type gastric carcinomas.