Overexpression of RCN1 correlates with poor prognosis and progression in non-small cell lung cancer.

We investigated the expression of reticulocalbin-1 (RCN1) and its prognostic significance in non-small cell lung cancer (NSCLC). RCN1 expression was evaluated by immunohistochemical analysis with tissue microarrays in NSCLC tissues and matched adjacent noncancerous tissues. Furthermore, quantitative polymerase chain reaction and Western blot were also used to examine the expression of RCN1. Moreover, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, clone formation, and transwell assays were used to measure cell proliferation, migration, and invasion. Lastly, we used the Kaplan-Meier method and log-rank test to compare overall survival rates between the RCN1-high expression group and the RCN1-low expression group. In this study, immunohistochemistry by tissue microarray at RCN1 expression was significantly up-regulated in NSCLC tissues compared with adjacent noncancerous tissues. We further confirmed the up-regulation of RCN1 by quantitative polymerase chain reaction and Western blot assay. RCN1 expression level was closely related to lymph node metastasis (P < .001) and TNM stage (P = .012). Kaplan-Meier analysis showed that high RCN1 expression was remarkably associated with poor prognosis with NSCLC patients. A suppression of cell proliferation, migration, and invasion was obtained in A549 cells treated with RCN1 small interfering RNA. Our data indicate that RCN1 expression may have an vital role at promoting the occurrence of NSCLC, and it may be a vital molecular marker in the diagnosis and prognosis of NSCLC patients.