PTK7 as a novel marker for favorable gastric cancer patient survival.

Protein tyrosine kinase 7 (PTK7) plays important functions in several cancer types but its expression in gastric cancer remains unknown. This study was designed to investigate PTK7 expression in gastric cancer. PTK7 expression was assessed by immunohistochemistry in 201 gastric cancer patients. The relationship between PTK7 expression and clinicopathological features and patients prognosis were statistically analyzed. PTK7 expression was detected in 56.72% (114 of 201) of gastric cancer patients. The immunostaining was predominantly localized in the cytoplasm. The statistical analyses showed that PTK7 expression was more frequently detected in patients with well-differentiated tumors (P = 0.001). Furthermore, PTK7 expression was significantly related to the favorable overall survival (OS; P = 0.012) and disease-free survival (DFS; P = 0.009). Multivariate Cox regression analyses revealed that PTK7 expression was an independent prognostic factor for both favorable OS (P = 0.028) and DFS (P = 0.012). Our findings demonstrate that PTK7 can serve as a novel prognostic biomarker for gastric cancer patients.