Comparison between 45 ovarian cancer (39 epithelial carcinoma and 6 borderline tissues) and 14 normal ovarian tissues.

<p>A) The plot of miRNA assays used to profile compared samples: fold change (y-axis) against normalized Ct measurements. B) Volcano plot of the resulting p-values of the t-test (y-axis) between the C and N groups. 305 miRNAs show FDR-adjusted p-values below 0.1 and fold change above 2 (shown in red). C) Hierarchical clustering (R package pvclust) of the 45 ovarian cancer tissues and 14 ovarian normal tissues based on top 50 most variable miRNA assays. For each cluster in hierarchical clustering, quantities called <i>p</i>-values (approximately unbiased <i>p</i>-value (red) and Bootstrap Probability p-value (green)) are calculated via multi-scale bootstrap resampling. <i>P</i>-value of a cluster is a value between 0 and 1, which indicates how strong the cluster is supported by data. D) 17% of the variance observed in the Ct measurements of top 50 most variable miRNA assays across all samples can be explained by sample pathology status (C or N). The remaining covariates considered here (source = hospital source, survival, tumor histology, FIGO stage, tumor grade, relapse, and stage) explain 24% of the variance.