期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2012
卷号:109
期号:17
页码:6584-6589
DOI:10.1073/pnas.1113271109
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Breast cancer is one of the most common cancers in humans. However, our understanding of the cellular and molecular mechanisms underlying tumorigenesis in breast tissues is limited. Here, we identified a molecular mechanism that controls the ability of breast cancer cells to form multicellular spheroids (mammospheres). We found that heregulin (HRG), a ligand for ErbB3, induced mammosphere formation of a breast cancer stem cell (BCSC)-enriched population as well as in breast cancer cell lines. HRG-induced mammosphere formation was reduced by treatment with inhibitors for phosphatidyl inositol 3-kinase (PI3K) or NF-{kappa}B and by expression of I{kappa}B-Super Repressor (I{kappa}BSR), a dominant-negative inhibitor for NF-{kappa}B. Moreover, the overexpression of I{kappa}BSR in breast cancer cells inhibited tumorigenesis in NOD/SCID mice. Furthermore, we found that the expression of IL8, a regulator of self-renewal in BCSC-enriched populations, was induced by HRG through the activation of the PI3K/NF-{kappa}B pathway. These findings illustrate that HRG/ErbB3 signaling appears to maintain mammosphere formation through a PI3K/NF-{kappa}B pathway in human breast cancer.
关键词:EGF ; HER ; tumor sphere ; cancer stem cells ; inflammation