Asporin Expression on Stromal Cells and/or Cancer Cells Might Be A Useful Prognostic Marker in Patients with Diffuse-Type Gastric Cancer

Abstract

<b><i>Background:</i></b> Asporin (ASPN), a member of the proteoglycan family, has been shown to have a close correlation with cancer progression. It is not known whether ASPN is an oncogenic driver or a tumor suppressor in human gastric cancer. We sought herein to determine the relationship between ASPN expression and clinicopathological features of gastric cancer. <b><i>Patients and Methods:</i></b> A total of 296 gastric cancer patients (diffuse type, <i>n</i> = 144; intestinal type, <i>n</i> = 152) were enrolled. The ASPN expression level in each case was analyzed by immunohistochemistry. <b><i>Results:</i></b> ASPN was mainly found on stromal cells, especially on fibroblasts in tumor stroma, i.e., cancer-associated fibroblasts. The ASPN expression on either cancer cells or stromal cells was significantly high in macroscopic scirrhous-type tumors (<i>p</i> &#x3c; 0.001) and histologically abundant stroma-type tumors (<i>p</i> &#x3c; 0.001). Interestingly, a Kaplan-Meier survival curve of the 144 cases of diffuse-type gastric cancer revealed a significantly poorer prognosis in patients with ASPN-positive expression (<i>p</i> = 0.043; log rank) compared to those with ASPN-negative expression, but the prognoses were not significantly different in these subgroups of the 152 cases of intestinal-type gastric cancer. A multivariate analysis with respect to overall survival showed that ASPN expression on stromal cells and/or cancer cells was significantly correlated with overall survival in patients with diffuse-type gastric cancer (<i>p</i> = 0.041). <b><i>Conclusion:</i></b> In gastric cancer, ASPN was expressed mainly on stromal cells and partially on cancer cells. ASPN expression on stromal cells and/or cancer cells might be a useful prognostic marker in patients with diffuse-type gastric cancer.