Expression of DOG-1 in gastrointestinal stromal tumors and its significance / 中华胃肠外科杂志

ABSTRACT

<p><b>OBJECTIVE</b>To identify the expression of DOG-1 in gastrointestinal stromal tumors (GIST) and to explore its potential association with clinicopathological features of GIST.</p><p><b>METHODS</b>Two tissue microarrays (TMA) were used for the study. Each TMA contained 80 tissue samples of GIST from 80 different patients, with each tumor represented by one core, and paraffin-embedded sections of 40 samples from normal gastrointestinal tissue were used as control. Immunohistochemistry staining (SABC method) was performed on TMA and paraffin-embedded sections to detected the expression of c-Kit (CD117) and DOG-1.</p><p><b>RESULTS</b>Immunohistochemistry showed that in 80 GIST patients, 76 cases (95.0%) were DOG-1 positive and 67 cases (83.8%) were CD117 positive. The positive rate of DOG-1 was higher than that of CD117 (P<0.05). In 13 GIST samples of negative CD117, the positive rate of DOG-1 was 100%. Expressions of both DOG-1 and CD117 were negative in all the 40 samples of normal gastrointestinal tissue. The positive expression of DOG-1 and CD117 was not significantly different in spindle cell type (96.0% vs. 96.0%, P>0.05) and in mixed cell type (91.7% vs. 75.0%, P>0.05). While in the epithelioid cell type, the DOG-1 expression was higher than CD117 expression (94.1% vs. 52.9%, P<0.05). The positive expression of DOG-1 and CD117 was not associated with age, gender, location and risk stratification of the tumors (all P>0.05).</p><p><b>CONCLUSIONS</b>DOG-1 expression is up-regulated in gastrointestinal stromal tumors, especially in epithelioid cell GIST, and may be used as a new marker in the diagnosis of GIST.</p>