Differentially expressed microRNAs in pancreatic cancer stem cells

The objective of this study was to analyze and identify pancreatic cancer stem cell-specific microRNAs (miRNAs) and messenger RNAs (mRNAs) to investigate their correlations to cancer stem cell biology. We used sphere cultivation methods to enrich the stem cell population and analyzed overall miRNA and mRNA expressions using microarray analysis. Differentially expressed miRNAs including miR-99a, miR-100, miR-125b, miR-192, and miR-429 were detected in pancreatic cancer stem cells. Furthermore, examining both profiles, we obtained 210 miRNAs and 258 stem cell-associated mRNAs that were differentially expressed in the pancreatic cancer stem cells. These miRNAs and mRNAs were further investigated using cross-correlation analysis, which yielded 6 groups of miRNAs and 3 groups of mRNAs. The number of miRNA clusters and mRNA clusters showed high correlation based on microarray result. Differentially expressed miRNAs in pancreatic cancer stem cells provide insights into possible linkages between clusters of miRNAs and clusters of stem cell-associated mRNAs in cancer stem cells and have broad implications in our understanding of cancer stem cells and cancer stem cell-targeted cancer therapy.