Multiple truncated transcripts of TSG101 in gastrointestinal cancers

The candidate tumour suppressor gene TSG101, located on chromosome 11p15, h as been associated with frequent intragenic deletion in uncultured primary human breast cancers. Using paired tumour and normal tissues from surgical specimens, we performed nested reverse transcriptase-polymerase chain react ion and direct sequencing to analyse TSG101 exons 1-6 from 32 gastric, 30 c olorectal and 16 oesophageal cancers. Truncated transcripts, were found in both tumour and normal tissues from the stomach (15.6 and 12.5%), colon (13 .3 and 3.3%) and oesophagus (25 and 25%). Multiple truncated transcripts in individual specimens were also observed. Two types of splicing patterns, o ne with three to six bases homology at the deletion junction (25.9%), the o ther with donor site 5' GT and acceptor site 3' AG (55.6%), were the most c ommon patterns. We conclude that in gastrointestinal cancers, truncated tra nscripts of TSG101 gene occur not uncommonly and do so with a specific spli cing pattern.