Abstract
Lung cancer is the most common cause of cancer-associated mortality in China with 85% of patients having non-small cell lung cancer (NSCLC). Identifying NSCLC driver genes and prognostic markers is critical to reducing these numbers. The studies of retinoblastoma binding protein 6 (RBBP6) performed on NSCLC is limited. The present study aimed to investigate the molecular function and the prognostic potential of RBBP6 in NSCLC using the A549 cell line and patient samples, respectively. The functional effect on cancer cell proliferation and prognostic value of RBBP6 were examined in vitro and in vivo using reverse transcription-quantitative PCR, immunofluorescence, immunohistochemistry (IHC) and xenograft implantation. The results demonstrated that RBBP6 mRNA expression was significantly higher in NSCLC tissues compared with in adjacent normal samples. When RBBP6 mRNA expression was interfered with using short hairpin RNA, A549 cell proliferation and xenograft tumor growth were reduced. Additionally, IHC and survival analysis demonstrated that patients with NSCLC with high expression levels of RBBP6 had a shorter median overall survival time compared with patients with low RBBP6 expression (31 vs. 51.5 months), and this was more prominent in stage I-II patients (43 vs. >67 months). High expression levels of RBBP6 indicated poor prognosis in patients with NSCLC. This may be due to the ability of RBBP6 to promote cancer cell proliferation. RBBP6 may be a potential prognostic biomarker and a therapeutic target for NSCLC.