LETM1 and thyroid gland undifferentiated (anaplastic) carcinoma: In addition, Gene Set Enrichment Analysis (GSEA) using public repository data (GSE33630, expression profiling by array of 11 anaplastic thyroid carcinomas (ATC), 49 PTC and 45 normal thyroids (N)) showed that platelet-derived growth factor (PDGF) signaling pathway was coordinately enriched in PTC with high LETM1 expression (P = 0.022, FDR q-value < 0.05, Figure 1E).