Differential expression profiles of circRNAs in human prostate cancer based on chip and bioinformatic analysis

Abstract

Background: Increasing evidence suggests that circRNAs are involved in the pathogenesis of multiple kinds of cancer. Nevertheless, the differential expression of circRNAs in prostate cancer (PCA) is rarely reported.

Material/method: In our present analyses, circRNAs expression profiles were identified in PCA, based on 5 pairs of PCA and matched non-PCA tissues using circRNA chips.

Results: A number of 749 differential circRNAs were expressed between PCA tumor and paracancerous tissues (Fold Change, FC ≥ 2.0 and P < 0.05): 261 were upregulated, whereas 487 were downregulated in PCA tissues. Gene ontology and KEGG pathway analyses indicated that many of the circRNAs are related to carcinogenesis. Circ_0033074 and circ_0016064 both showed changes of maximum magnitude among differentially expressed circRNAs.

Conclusions: Our study detected a relative comprehensive differential map of circRNAs in PCA, which may become novel biomarkers for diagnosis, treatment and follow-up in the future.

Keywords: Prostate cancer; circRNA; expression; microarray.

Figure 1

Hierarchical clustering, volcano plots, and scatter plots displayed the differentially expressed circRNAs in PCA tissues compared to paracancerous tissues. A. Hierarchical clustering: numbers were the samples used for the microarray assay. T: PCA tissues, N: paracancerous tissues. B. Differentially expressed circRNAs are shown as volcano plots. The blue and red parts indicate (FC more than 2 folds) downregulated and upregulated expression circRNAs in PCA tissues, respectively (P < 0.05). C. Differentially expressed circRNAs shown by scatter plots. The green and red parts indicate (FC more than 2 folds) downregulated and upregulated expression circRNAs in PCA tissues, respectively (P < 0.05).

Figure 2

GO and KEGG pathway analysis of differentially expressed circRNAs. A. GO enrichment terms of top 30 classes. B. KEGG pathway enrichment terms of top 30 classes.