Clinical significance of nuclear localisation of agrin in lung adenocarcinoma.

Agrin has recently been identified as a novel oncogene that is overexpressed in several types of human cancers. However, its role in lung cancer has not yet been investigated. The purpose of the current study was to investigate agrin protein expression in lung cancer and evaluate its clinicopathological and prognostic significance. In this study, A total of 86 lung adenocarcinoma samples paired with adjacent non-tumour tissue samples and eight lung adenocarcinoma non-paired samples were selected for immunohistochemical staining for agrin. Strong staining of agrin in nuclei of lung adenocarcinoma tissues was observed, but not in the nuclei of normal lung tissues (p < 0.001). Consistent with staining in lung adenocarcinoma tissues, the nuclei staining of agrin was also detected in lung cancer cell lines by immunofluorescence. This is the first report demonstrating that agrin is highly expressed in nuclei of lung adenocarcinoma tissues and that it is strongly correlated with lymph node metastasis (p = 0.002), clinical stage (p = 0.024), and poor differentiation (p = 0.022). Agrin-positive nuclear staining of lung adenocarcinoma cells could be used to identify greatly increased risk of metastasis in patients after surgery, which might serve as a valuable prognostic marker.