miRNA profiling of DFTD. Heat map of normalized miRNA reads for 114 miRNAs cloned and sequenced from 10 Tasmanian devil tissues; four DFTD facial tumors (DFTD1, 2, 3, and 20); and one DFTD mammary metastasis (DFTD2, met). miRNAs were clustered on the basis of Pearson’s correlation statistic, and bootstrap values (percentage) are indicated. The DFTD miRNA profile is shown in greater detail. miRNAs were annotated on the basis of conservation with comparison species hsa, human; mdo, opossum.

DFTD transcriptome. (A) Semiquantitative RT-PCR expression profiling of 31 genes with enriched expression in tumor relative to testis [454–read count fold change ≥2.5, P ≤ 0.05, chi-squared test; (green points in fig. S5)]. Log values of the mean expression difference of DFTD genes relative to testis (blue bars) and relative to GAPDH (red bars) are shown. Error bars represent standard deviation. Significant differences between tumor and testis expression levels (P ≤ 0.05) are indicated by an asterisk (two-sample t test, Holm’s correction for multiple testing). (B) Heat map of semiquantitative PCR expression profiles of 31 genes across a panel of tissues including peripheral nerve (PN), a Schwann cell–enriched tissue. Panel color represents the mean gene expression level, standardized across tissues (z score). Hierarchical clustering based on Pearson’s correlation statistic is indicated by dendrograms. For each tissue three biological replicates were performed (n = 3). ND, not determined.

Identification of a diagnostic marker for DFTD. (A to D) Hematoxylin and eosin (H&E) and (E to H) PRX antibody stains used for DFTD tumor histology. Arrowheads, DFTD tissue; arrows, peripheral nerve bundles (containing Schwann cells). Magnification, 4× (A and E; scale bar, 200 μm); 20× (B and F; scale bar, 50 μm); and 100× (C and G) peripheral nerve bundle (scale bar, 20 μm) and (D and H) DFTD tumor (scale bar, 20 μm). Boxed areas indicate approximate locations of areas magnified in lower panels.