Microarray expression profile of long non-coding RNAs in human lung adenocarcinoma

Background: Long non-coding RNAs (lncRNAs) participate in many biological dynamics and play significant roles in gene regulation. LncRNA expression is altered in many cancers; however, the expressions and functions of lncRNA genes in lung adenocarcinoma (LAD) remain unknown.

Methods: LncRNA and messenger RNA (mRNA) expression in LAD without lymphatic metastasis versus paired adjacent non-tumor (ANT) lung tissues and LAD with versus without lymphatic metastasis were analyzed using Human LncRNA Arraystar V3.0. The expression levels of four downregulated and four upregulated lncRNAs were verified using quantitative real-time PCR in cells and tissue specimens.

Results: In this study, 949 lncRNAs and 681 mRNAs had differential expression in LAD without lymphatic metastasis compared to ANT lung tissues, while 2740 lncRNAs and 1714 mRNAs were differentially expressed in LAD with lymphatic metastasis compared to LAD without lymphatic metastasis. The expression patterns of selected lncRNAs (LINC00113, AC005009.1, ARHGAP22-IT1, AC009411.1, SRGAP3-AS2, EGFEM1P, FAM66E, and HLA-F-AS1) were consistent with microarray data. Differentially expressed mRNA genes were enriched in crucial Gene Ontology terms and pathways.

Conclusion: Our results revealed differentially expressed lncRNAs in LAD, suggesting lncRNAs may be potential indicators for LAD diagnosis and therapy.