TY - JOUR
T1 - Concordant effects of aromatase inhibitors on gene expression in ER+ rat and human mammary cancers and modulation of the proteins coded by these genes
AU - Lu, Yan
AU - You, Ming
AU - Ghazoui, Zara
AU - Liu, Pengyuan
AU - Vedell, Peter T.
AU - Wen, Weidong
AU - Bode, Ann M.
AU - Grubbs, Clinton J.
AU - Lubet, Ronald A.
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013/11
Y1 - 2013/11
N2 - Aromatase inhibitors are effective in therapy/prevention of estrogen receptor-positive (ER+) breast cancers. Rats bearing methylnitrosourea (MNU)-induced ER+ mammary cancers were treated with the aromatase inhibitor vorozole (1.25 mg/kg BW/day) for five days. RNA expression showed 162 downregulated and 180 upregulated (P < 0.05 and fold change >1.5) genes. Genes modulated by vorozole were compared with published data from four clinical neoadjuvant trials using aromatase inhibitors (anastrozole or letrozole). More than 30 genes and multiple pathways exhibited synchronous changes in animal and human datasets. Cell-cycle genes related to chromosome condensation in prometaphase [anaphase-prometaphase complex (APC) pathway, including Aurora-A kinase, BUBR1B, TOP2, cyclin A, cyclin B CDC2, and TPX-2)] were downregulated in animal and human studies reflecting the strong antiproliferative effects of aromatase inhibitors. Comparisons of rat arrays with a cell culture study where estrogen was removed from MCF-7 cells showed decreased expression of E2F1-modulated genes as a major altered pathway. Alterations of the cell cycle and E2F-related genes were confirmed in a large independent set of human samples (81 pairs baseline and two weeks anastrozole treatment). Decreases in proliferation-related genes were confirmed at the protein level for cyclin A2, BuRB1, cdc2, Pttg, and TPX-2. Interestingly, the proteins downregulated in tumors were similarly downregulated in vorozole-treated normal rat mammary epithelium. Finally, decreased expression of known estrogen-responsive genes (including TFF, 1,3, progesterone receptor, etc.) were decreased in the animal model. These studies demonstrate that gene expression changes (pathways and individual genes) are similar in humans and the rat model.
AB - Aromatase inhibitors are effective in therapy/prevention of estrogen receptor-positive (ER+) breast cancers. Rats bearing methylnitrosourea (MNU)-induced ER+ mammary cancers were treated with the aromatase inhibitor vorozole (1.25 mg/kg BW/day) for five days. RNA expression showed 162 downregulated and 180 upregulated (P < 0.05 and fold change >1.5) genes. Genes modulated by vorozole were compared with published data from four clinical neoadjuvant trials using aromatase inhibitors (anastrozole or letrozole). More than 30 genes and multiple pathways exhibited synchronous changes in animal and human datasets. Cell-cycle genes related to chromosome condensation in prometaphase [anaphase-prometaphase complex (APC) pathway, including Aurora-A kinase, BUBR1B, TOP2, cyclin A, cyclin B CDC2, and TPX-2)] were downregulated in animal and human studies reflecting the strong antiproliferative effects of aromatase inhibitors. Comparisons of rat arrays with a cell culture study where estrogen was removed from MCF-7 cells showed decreased expression of E2F1-modulated genes as a major altered pathway. Alterations of the cell cycle and E2F-related genes were confirmed in a large independent set of human samples (81 pairs baseline and two weeks anastrozole treatment). Decreases in proliferation-related genes were confirmed at the protein level for cyclin A2, BuRB1, cdc2, Pttg, and TPX-2. Interestingly, the proteins downregulated in tumors were similarly downregulated in vorozole-treated normal rat mammary epithelium. Finally, decreased expression of known estrogen-responsive genes (including TFF, 1,3, progesterone receptor, etc.) were decreased in the animal model. These studies demonstrate that gene expression changes (pathways and individual genes) are similar in humans and the rat model.
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U2 - 10.1158/1940-6207.CAPR-13-0126
DO - 10.1158/1940-6207.CAPR-13-0126
M3 - Article
C2 - 24067424
AN - SCOPUS:84887878472
SN - 1940-6207
VL - 6
SP - 1151
EP - 1161
JO - Cancer Prevention Research
JF - Cancer Prevention Research
IS - 11
ER -