Aim: We sought to address the mechanisms by which intestinal gastrointestinal stromal tumors (GIST) have a markedly higher risk of recurrence than gastric GISTs.
Materials and methods: Gene expression levels were compared among six primary gastric, three intestinal and six metastatic liver GISTs using cDNA microarray. Protein levels of Slit homolog 2 (SLIT2) were analyzed by immunohistochemistry in 25 primary gastric and 10 intestinal GIST.
Results: Intestinal GIST had gene expression profiles similar to clinically malignant and metastatic GIST. In gene set-enrichment analysis, the gene sets MITOTIC_CELL CYCLE and NEURON_DIFFERENTIATION were up-regulated and down-regulated, respectively, in intestinal GIST compared to gastric GIST. High-risk gastric GISTs and intestinal GIST, expressed similar levels of SLIT2 protein, which were lower than those of low-risk gastric GISTs.
Conclusion: The gene-expression profile of intestinal GISTs was similar to that of metastatic liver GISTs. Besides higher proliferative activity, down-regulation of SLIT2 might be involved in clinically malignant phenotypes of intestinal GIST.
Keywords: Gastrointestinal stromal tumor; SLIT2; intestine; microarray; stomach.
Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.