Inverse agonist of estrogen-related receptor ? suppresses the growth of triple negative breast cancer cells through ROS generation and interaction with multiple cell signaling pathways.
Ontology highlight
ABSTRACT: There is an urgent clinical need for targeted therapy approaches for triple-negative breast cancer (TNBC) patients. Increasing evidences suggested that the expression of estrogen-related receptor alpha (ERR?) was correlate with unfavorable clinical outcomes of breast cancer patients. We here show that inhibition of ERR? by its inverse agonist XCT-790 can suppress the proliferation, decrease G2/M phases, and induce mitochondrial-related apoptosis of TNBC cells. XCT-790 elevates the proteins related to endoplasmic reticulum (ER) stress such as ATF4/6, XBT-1 and CHOP. It also increases the expression of growth inhibition related proteins such as p53 and p21. Further, XCT-790 can increase the generation of reactive oxygen species (ROS) in TNBC cells mainly through inhibition of SOD1/2. While ROS scavenger NAC abolishes XCT-790 induced ER-stress and growth arrest. XCT-790 treatment can rapidly activate the signal molecules including ERK1/2, p38-MAPK, JNK, Akt, p65, and I?B?, while NAC attenuates effects of XCT-790 induced phosphorylation of ERK1/2, p38-MAPK and Akt. Further, the inhibitors of ERK1/2, JNK, Akt, and NF-?B attenuate XCT-790 induced ROS generation. These data suggest that AKT/ROS and ERK/ROS positive feedback loops, NF-?B/ROS, and ROS/p38-MAPK, are activated in XCT-790 treated TNBC cells. In vivo experiments show that XCT-790 significantly suppresses the growth of MDA-MB-231 xenograft tumors, which is associated with up regulation of p53, p21, ER-stress related proteins while down regulation of bcl-2. The present discovery makes XCT-790 a promising candidate drug and lays the foundation for future development of ERR?-based therapies for TNBC patients.
SUBMITTER: Wu YM
PROVIDER: S-EPMC4914305 | biostudies-literature | 2016 Mar
REPOSITORIES: biostudies-literature
ACCESS DATA