PT  - JOURNAL ARTICLE
AU  - R Salovaara
AU  - S Roth
AU  - A Loukola
AU  - V Launonen
AU  - P Sistonen
AU  - E Avizienyte
AU  - P Kristo
AU  - H Järvinen
AU  - S Souchelnytskyi
AU  - M Sarlomo-Rikala
AU  - L A Aaltonen
TI  - Frequent loss of SMAD4/DPC4 protein in colorectal cancers
AID  - 10.1136/gut.51.1.56
DP  - 2002 Jul 01
TA  - Gut
PG  - 56--59
VI  - 51
IP  - 1
4099  - http://gut.bmj.com/content/51/1/56.short
4100  - http://gut.bmj.com/content/51/1/56.full
SO  - Gut2002 Jul 01; 51
AB  - Background and aims: Loss of DNA sequences from chromosome 18q21 is a major genetic change in colorectal tumorigenesis. Multiple genes have been identified in this area. One of these, DPC4 (deleted in pancreatic cancer 4, also known as SMAD4), is mutated in a minor subset of colorectal carcinomas as well as in germlines of humans predisposed to colon tumours. Patients and methods: The involvement of SMAD4 in sporadic colorectal neoplasia was evaluated by immunohistochemistry in 53 unselected cases and 27 cases displaying microsatellite instability. Results: SMAD4 expression was absent in 20 of 53 (38%) unselected colorectal carcinomas, and reduced in another 15 (28%) cases. However, 26 of 27 cancers displaying microsatellite instability and TGF-βIIR mutations were positive for SMAD4 immunostaining. Conclusions: Loss of SMAD4 expression may play a more prominent role in colon cancer than anticipated based on genetic evidence, but not in mutator phenotype tumours.