Clinical significance of stanniocalcin 2 as a prognostic marker in gastric cancer

Background: Stanniocalcins are glycoprotein hormones that were originally found in the endocrine gland of bony fish. Microarray expression data from 32 paired samples of gastric cancer and normal mucosa in a public microarray database showed that the expression level of Stanniocalcin 2 was higher in gastric cancer than in normal gastric mucosa. The clinical significance of Stanniocalcin 2 expression has been observed for several cancers. However, the relationship between Stanniocalcin 2 and clinicopathological factors in gastric cancer has not yet been investigated. Materials and Methods: We examined the clinical significance of Stanniocalcin 2 in gastric cancer in 108 gastric cancer samples using real-time reverse transcription-polymerase chain reaction (RT-PCR). Immunohistochemical studies were conducted with paraffin sections. The suppression analysis of Stanniocalcin 2 using siRNA was done to determine Stanniocalcin 2's biological roles. Results: The level of Stanniocalcin 2 in cancer tissues was higher than in normal tissues (P = .0002). The high Stanniocalcin 2 expression group (n = 54) had more progressive lymph node metastasis (P = .07) and venous invasion (P = .028) than the low-expression group (n = 54). High Stanniocalcin 2 expression was an independent prognostic factor in gastric cancer patients (P = .02). Moreover, siRNA suppression of Stanniocalcin 2 in a gastric cancer cell line inhibited cellular proliferation (P < .05). Conclusions: The high expression level of Stanniocalcin 2 in gastric cancer tissues could be a very powerful marker of poor prognosis. Therefore, Stanniocalcin 2 is a promising candidate for a molecular target for the treatment of gastric cancer.