„Angiogenesis gene expression across different life stages in non-human primates (Macaca fascicularis)“

Aims:
To investigate the impact of reproductive life stages on the angiogenesis gene expression profiles of the mammary gland in a primate model, in comparison to the hormone treated postmenopausal mammary gland and breast cancer (BC)
Methods: Comparative transcriptomic analyses were carried out using breast tissues from 37 female cynomolgus macaques at different life stages: Prepuberty, adolescence, adults in the luteal phase of the menstrual cycle, pregnancy, lactation and postmenopause, compared to treatment with tamoxifen (TAM), treatment with hormone replacement therapy (CEE&MPA) and BC. Mammary gland RNA hybridized to a rhesus macaque genome microarray. Differential gene expression was analyzed using ANOVA with adjusted p-values and cluster analysis. Angiogenesis markers ADAM12, bFGF, HIF-1a, KDR, Ki-67, MMP-9, PDGFB, PECAM-1, TGF-ß, THBS1 and VEGFA were measured by qRT-PCR and analyzed using nonparametric group-wise statistics. Protein translation of ADAM12, bFGF, KDR, PDGFB, TGF-ß and VEGFA was localized and quantitatively evaluated by immunohistochemistry (IHC).
Results: Gene Expression Arrays: Hierarchical cluster analysis revealed distinct separation of life stage groups, BC, TAM and CEE&MPA treated gland, respectively. PCR: ADAM12 mRNA was highest in juveniles and pregnant animals. MMP-9 and THBS1 mRNA were elevated in pregnancy. PDGFB, bFGF and TGF-ß expression was highest in TAM and lowest in BC. In contrast VEGFA, KDR, HIF-1, PECAM-1 and Ki-67 expression was highest in pregnant animals, KDR, HIF-1a, PECAM-1 expression was lowest in the adolescents. IHC: Each marker had different protein expression patterns and localizations.
Conclusion: Our data demonstrate distinct patterns of angiogenesis gene expression during breast development, (anti-)estrogenic treatment and in BC. Microanatomic relationships indicate paracrine signaling between glandular and vascular structures may be important.