PURPOSE: Tetraspanin CD151 is known to be involved in cancer invasion and metastasis, and its overexpression appears to be associated with a poor prognosis for various types of cancer. However, the expression status of CD151 and its prognostic impact in advanced gastric cancer (AGC) has not yet been clarified.
METHODS: Immunohistochemistry was used to investigate the expression of CD151, c-erbB2, and c-Met in 159 cases of AGC. The clinicopathological and prognostic significance of these biomarkers were then evaluated.
RESULTS: The overexpression of CD151 was observed in a subset of advanced gastric adenocarcinomas (25.8 %), and c-erbB2 and c-Met were overexpressed in 15.1 and 35.2 % of the cohort, respectively. CD151 overexpression was more frequently observed in tumors from younger patients (P = 0.028). There were close associations between CD151 and c-erbB2 overexpression (P = 0.033) and between c-erbB2 and c-Met overexpression (P = 0.001). CD151 overexpression was closely correlated with patient' overall survival (OS; P < 0.001) and disease-free survival (DFS; P < 0.001). Furthermore, the expression rate of CD151 seemed to increase gradually according to the depth of invasion (T stage) (χ(2) test for trend; P = 0.101), N stage (P = 0.238), and pathologic stage (P = 0.153), although trends were not statistically significant. In a multivariate analysis, CD151 overexpression was an independent prognostic factor predicting worse OS (P = 0.002) and DFS (P = 0.005), along with the T and N stage.
CONCLUSIONS: CD151 was found to be an independent prognostic marker for patients with AGC.