Differential expression of glucocorticoid receptor in carcinomas of the human digestive system

Aims: To investigate the in situ expression profile of glucocorticoid receptor (GR) in normal and carcinomatous tissues of the human digestive system. Methods and results: Specimens from 306 carcinomas of the human digestive tract were assayed for the expression of GR by immunohistochemistry. GR expression was strong in oesophageal squamous epithelia, pancreatic islet cells and hepatocytes, but generally weak or negative in non‐squamous epithelia. Consistently, GR expression was found in a high percentage of oesophageal squamous cell carcinomas (SCC) (98.1%) and hepatocellular carcinomas (HCC) (92.9%), but rarely in gastric adenocarcinomas (7.4%) and not at all in colorectal adenocarcinomas (0%). Dexamethasone (DEX) was found to confer chemoresistance in oesophageal SCC and HCC cells, suggesting that GR expression may be biologically important in some GR‐expressing carcinomas. Conclusions: Distribution of GR expression is markedly diverse among tissues of the human digestive system. The general lack of GR in adenocarcinomas contrasts with the high percentage of SCCs and HCCs expressing GR, and, along with the generation of chemoresistance by DEX, warrants prospective study of the effects of steroids on these cancers.