The long noncoding RNA expression profile of human intervertebral disc degeneration identified by microarray analysis

In addition to the well-known short noncoding RNAs as miRNAs, increasing evidence suggests that long noncoding RNAs (lncRNAs) act as key regulators in a wide aspect of biologic processes. Dysregulated expression of lncRNAs has been demonstrated being implicated in a variety of human diseases. However, there is relative paucity of information regarding the role of lncRNAs in intervertebral disc degeneration (IDD) hitherto. We have addressed the expression profiles of miRNAs in IDD previously. To determine whether lncRNAs is differentially expressed in IDD, we employed a lncRNA-mRNA microarray analysis of human nucleus pulposus (five degenerative as IDD and five normal specimens as control). With abundant probes accounting for 33,045 lncRNAs and 30,215 coding transcripts in our microarray, microarray data profiling indicated that 18995 lncRNAs and 14635 mRNAs were detected in all samples with 2309 lncRNAs and 3017 mRNAs differentially expressed in degenerated samples. Amongst them, 164 lncRNAs (97 up and 67 down) and 265 mRNAs were highly differentially expressed with an absolute fold change greater than ten. The upregulated mRNAs included the extracellular matrix components as COL1A2, LUM, FN1ACAN, DCN and ITFG2. 1100 lncRNAs and 1379 mRNAs were altered in the same direction in at least 4 of the 5 degenerative samples with fold change greater than 2 respectively. Three lncRNAs were chosen for the real-time quantitative PCR (qRT-PCR) analysis. qRT-PCR results showed a high consistency with the microarray data. In this study, to explore the potential involvement of lncRNAs in IDD, we conducted lncRNA and mRNA profiling in 5 human control nucleus pulposus tissue and 5 degenerative nucleus pulposus tissue by microarray.Biological replicates: 5 control, 5 degenerated, independently harvested.