miRNA Expression Profiling of Murine Neuroblastoma Figure 1. Hierarchical cluster and expression analysis of mouse tumors. (A) Hierarchical clustering (n = 440) of mouse samples. Cluster ‘‘Adrenals’’ contains all the adrenals, while all the tumors samples fall into the cluster ‘‘Tumors’’ The overall miRNAs profile did not resolve the TH- MYCN (green) and TH-MYCN/p53ERTAM (blue) tumors, or the adrenals derived from wild type (black), TH-MYCN (brown) and TH-MYCN/p53ERTAM (yellow). (B)–(C). Expression of miR-125b-3p and miR-676 in TH-MYCN (n = 9) and TH-MYCN/p53ERTAM tumors (n = 13). The miRNAs are significantly down-regulated in the tumors lacking half of the active p53 protein, after Bonferroni multiple comparison correction (respectively p,0.01 and p,0.03). doi:10.1371/journal.pone.0028356.g001 that were inconsistent in the mouse/human comparison map to a large cluster on chromosome 14q in humans (mouse chromosome 12). Overall, these results showed high concordance in miRNA expression between murine and human neuroblastoma, with the aforementioned exceptions. Using data previously obtained in our laboratory, we directly compared the miRNA profile of human and mouse tumors. The cohort of 146 human tumors included 36 tumors MNA and 110 samples non-MNA [12]. Comparison between human and mouse tumors was complicated by the fact that not all miRNAs in the PLoS ONE | www.plosone.org 3 December 2011 | Volume 6 | Issue 12 | e28356