Increased expression of Fibulin-5 in gastric cancer associated with poor prognosis

The expression of Fibulin-5 and Ki67 proteins has been demonstrated to play important roles in tumor development and progression. However, the detailed clinical implications of them have not been well understood, especially in gastric cancer. In this study, immunohistochemistry was applied to investigate the expression levels of Fibulin-5 and Ki67 in a tissue microarray with following-up information, including 90 gastric cancer cases and paired para-carcinoma tissues. The results showed that the expression levels of Fibulin-5 and Ki67 in gastric cancer tissues were significantly higher than those in para-carcinoma tissues (P<0.05), and the expression of Fibulin-5 was significantly positive correlated with Ki67' s expression (r>0, P<0.05). Clinical correlation analysis showed that the expression of Fibulin-5 in tumor cytoplasm and Ki67 in tumor cell nucleus was positively correlated with patients' age (r=0.213, P=0.044 and r=0.241, P=0.023, respectively). Expression of Ki67 also positively correlated with the tumor size (r=0.249, P=0.021). Survival analysis showed that Fibulin-5 expression in the cytoplasm of cancer tissue was significantly associated with poor prognosis of gastric cancer patients (25.0% vs. 55.6%, P=0.027), as an independent prognostic factor (P=0.037). Patients with higher Fibulin-5 expression in cancer nucleus also associated with poor survival, but their association was not significant (27.8% vs. 54.5%, P=0.141). In conclusion, the present study suggested that Fibulin-5 was overexpressed in gastric cancer and associated with a poor prognosis, which might serve as a novel biomarker for prognosis prediction in gastric cancer, as well as a potential therapeutic target.