Increased Expression of Long Non-Coding RNA BCAR4 Is Predictive of Poor Prognosis in Patients with Non-Small Cell Lung Cancer

Abstract

Lung cancer is the most common human cancer, and the majority of lung cancer cases are categorized as non-small cell lung cancer (NSCLC). Long non-coding RNAs (lncRNAs) play key roles in the development and progression of human cancers. LncRNA breast cancer anti-estrogen resistance 4 (BCAR4) has been identified as an oncogenic lncRNA involved in the progression of breast cancer and osteosarcoma. However, the clinical significance of the lncRNA BCAR4 in NSCLC remains largely unclear. In the present study, real-time quantitative reverse transcriptase-polymerase chain reaction was used to examine the relative level of lncRNA BCAR4 in 68 cases of NSCLC tissues and their adjacent non-tumor tissues. Our data showed that the expression level of lncRNA BCAR4 was significantly higher in NSCLC tissues compared to their matched non-tumor tissues. Moreover, BCAR4 expression was significantly upregulated in NSCLC cell lines, when compared to the normal human bronchial epithelial cell line BEAS-2B. In addition, the BCAR4 expression was associated with the lymph node metastasis, distant metastasis and clinical stage, but not with the age, sex, tumor size, histological grade, and histological type. The increased expression of BCAR4 was significantly associated with poorer 5-year overall survival rate of NSCLC patients. Multivariate survival analysis indicated that BCAR4 was an independent prognostic factor for NSCLC patients. Taken together, our study suggests that the upregulation of lncRNA BCAR4 expression plays a promoting role in the malignant progression of NSCLC. Thus, BCAR4 is a potential biomarker for NSCLC progress and a therapeutic target for NSCLC.