Interception targets of Angelica Gigas Nakai root extract vs. pyranocoumarins in prostate early lesions and neuroendocrine carcinomas in TRAMP mice

We reported efficacy of Angelica gigas Nakai (AGN) root ethanol extract and equimolar decursin (D)/decursinol angelate (DA) through daily gavage starting at 8 weeks of age (WOA) to male transgenic adenocarcinoma of mouse prostate (TRAMP) mice such that these modalities suppressed precancerous epithelial lesions in their dorsolateral prostate (DLP) to similar extent, but AGN extract was better than the D/DA mixture at promoting the survival of mice bearing prostate neuroendocrine carcinomas (NECa) to 28 WOA (Tang et al, Cancer Prev Res 2015). Here, we compared by microarray hybridization the mRNA levels in pooled DLP tissues and individual NECa to characterize potential molecular targets of AGN extract and D/DA. Clustering and principal component analyses supported distinct gene expression profiles of TRAMP DLP vs. NECa. Pathway Enrichment, Gene Ontology and Ingenuity Pathway Analyses of differential genes indicated that AGN and D/DA affected chiefly processes of lipid and mitochondrial energy metabolism and oxidation-reduction in TRAMP DLP, while AGN affected neuronal signaling, immune systems and cell cycling in NECa. Protein-Protein Interaction Network analysis predicted and reverse transcription-PCR verified multiple hub genes common in the DLP of AGN- and D/DA-treated TRAMP mice at 28 WOA and select hub genes attributable to the non-D/DA AGN components. The vast majority of hub genes in the AGN-treated NECa differed from those in TRAMP DLP. In summary, the transcriptomic approach illuminated vastly different signaling pathways and networks, cellular processes and hub genes of two TRAMP prostate malignancy lineages and their associations with the interception efficacy of AGN and D/DA. TRAMP mice treated with AGN and sacrificed at 16 and 28 WOA (AGN TRAMP DLP 16wk [n=10] or 28wk [n=14]); TRAMP mice treated with D/DA and sacrificed at 16 and 28 WOA (D/DA TRAMP DLP 16wk [n=11] or 28wk [n=13]). In addition, we selected 3 NECa each from vehicle-treated mice and AGN-treated mice and 2 WT whole prostates (24-28 WOA) for RNA isolation. RNA from the 16 samples was extracted by using the AllPrep DNA/RNA/Protein Mini kit (QIAGEN Inc., Valencia, CA) according to the manufacturer's protocol.