P1.05-018 LncRNA16 is a Potential Biomarker for Early-Stage Lung Cancer That Promotes Cell Proliferation by Regulating the Cell Cycle

Abstract

Early diagnosis of lung cancer greatly reduces mortality; however, the lack of suitable plasma biomarkers presents a major obstacle. Recent studies showed that long noncoding RNAs (lncRNAs) play important roles in cancer initiation and development. Here, we identify differential expressed lncRNAs by using custom designed microarray on 20 lung cancer samples and evaluate the expression by Real-time PCR (qRT-PCR) on 118 lung cancer samples. The role of lncRNA16 in lung cancer was studied in vitro and in vivo, utilizing the lung cancer cell line PC9, A549 and xenograft mouse models. lncRNA16 (ENST00000539303) expression level was highly in lung cancer (80/118) and in plasma (32/42) of lung cancer patients. In early stage, lncRNA16 expression levels were significantly higher compare to that in adjacent matched normal tissues (Figure 1C-1F). Importantly, this increase was mirrored in plasma samples of early stage lung cancer patients (Figure 2A). Our study reveals that knockdown of lncRNA16 inhibited proliferation of PC9 cells in vitro and also inhibited tumor growth in xenograft mouse models. Specifically, we show that lncRNA16 promotes G2/M transition through regulating cyclin B1 transcription. In conclusion, lncRNA16 was identified as a potential biomarker for lung cancer diagnosis, as it displayed significantly elevated levels in cancer patient over baseline. Furthermore, we showed that the false-negative rate is significantly lower compared to markers those widely used for lung cancer assessment.