Expression of resistin-like molecule beta in gastric cancer: its relationship with clinicopathological parameters and prognosis

摘要

Resistin-like molecule beta (RELMβ), an intestinal goblet cell-specific protein, is a biomarker of intestinal metaplasia in Barrett’s esophagus and over-expressed in colon cancer. Since gastric adenocarcinomas can arise through a process of intestinalization, we hypothesized that RELMβ might be aberrantly expressed in gastric cancer. This study was undertaken to examine the RELMβ expression in gastric cancer and correlate it with clinical outcome. One hundred and thirty-six gastric cancer patients were evaluated for the RELMβ expression by immunohistochemistry. The RELMβ transcripts were measured by real-time quantitative PCR. In normal gastric mucosa, RELMβ expression was absent, whereas areas of intestinal metaplasia revealed RELMβ reactivity. Eighty-nine patients of gastric cancer (65.4%) were positive for RELMβ expression. In a subtotal of 20 patients, RELMβ transcripts were positively correlated with protein levels in gastric cancer tissues, but absent in normal gastric mucosa. The expression rate of RELMβ was higher in intestinal-type carcinomas than in diffuse-type carcinomas (P < 0.001). RELMβ positivity in gastric cancer was positively correlated with tumor differentiation (P = 0.001) and inversely correlated with tumor infiltration (P = 0.007), lymph node metastasis (P = 0.035), and heparanase expression (P < 0.001), without correlation with age, gender, tumor location and size, tumor-node metastasis stages, and Ki-67 expression. Patients showing positive RELMβ expression had a significantly longer overall survival than those with negative expression (P = 0.001). These results provide evidences that the RELMβ expression in gastric cancer is correlated with clinicopathological features and may be a useful prognostic factor for predicting the outcome of gastric cancer patients. Keywords Resistin-like molecule beta - Gastric cancer - Gene expression