TY - JOUR
T1 - Residual breast cancers after conventional therapy display mesenchymal as well as tumor-initiating features
AU - Creighton, Chad J.
AU - Li, Xiaoxian
AU - Landis, Melissa
AU - Dixon, J. Michael
AU - Neumeister, Veronique M.
AU - Sjolund, Ashley
AU - Rimm, David L.
AU - Wong, Helen
AU - Rodriguez, Angel Augusto
AU - Herschkowitz, Jason I.
AU - Fan, Cheng
AU - Zhang, Xiaomei
AU - He, Xiaping
AU - Pavlick, Anne
AU - Gutierrez, M. Carolina
AU - Renshaw, Lorna
AU - Larionov, Alexey A.
AU - Faratian, Dana
AU - Hilsenbeck, Susan G.
AU - Perou, Charles M.
AU - Lewis, Michael T.
AU - Rosen, Jeffrey M.
AU - Chang, Jenny C.
PY - 2009/8/18
Y1 - 2009/8/18
N2 - Some breast cancers have been shown to contain a small fraction of cells characterized by CD44+/CD24-/low cell-surface antigen profile that have high tumor-initiating potential. In addition, breast cancer cells propagated in vitro as mammospheres (MSs) have also been shown to be enriched for cells capable of self-renewal. In this study, we have defined a gene expression signature common to both CD44+/CD24-/low and MS-forming cells. To examine its clinical significance, we determined whether tumor cells surviving after conventional treatments were enriched for cells bearing this CD44+/ CD24-/low-MS signature. The CD44+/CD24-/low-MS signature was found mainly in human breast tumors of the recently identified "claudin-low" molecular subtype, which is characterized by expression of many epithelial-mesenchymal- transition (EMT)-associated genes. Both CD44+/CD24-/low-MS and claudin-low signatures were more pronounced in tumor tissue remaining after either endocrine therapy (letrozole) or chemotherapy (docetaxel), consistent with the selective survival of tumor-initiating cells posttreatment. We confirmed an increased expression of mesenchymal markers, including vimentin (VIM) in cytokeratin-positive epithelial cells metalloproteinase 2 (MMP2), in two separate sets of postletrozole vs. pretreatment specimens. Taken together, these data provide supporting evidence that the residual breast tumor cell populations surviving after conventional treatment may be enriched for subpopulations of cells with both tumor-initiating and mesenchymal features. Targeting proteins involved in EMT may provide a therapeutic strategy for eliminating surviving cells to prevent recurrence and improve long-term survival in breast cancer patients.
AB - Some breast cancers have been shown to contain a small fraction of cells characterized by CD44+/CD24-/low cell-surface antigen profile that have high tumor-initiating potential. In addition, breast cancer cells propagated in vitro as mammospheres (MSs) have also been shown to be enriched for cells capable of self-renewal. In this study, we have defined a gene expression signature common to both CD44+/CD24-/low and MS-forming cells. To examine its clinical significance, we determined whether tumor cells surviving after conventional treatments were enriched for cells bearing this CD44+/ CD24-/low-MS signature. The CD44+/CD24-/low-MS signature was found mainly in human breast tumors of the recently identified "claudin-low" molecular subtype, which is characterized by expression of many epithelial-mesenchymal- transition (EMT)-associated genes. Both CD44+/CD24-/low-MS and claudin-low signatures were more pronounced in tumor tissue remaining after either endocrine therapy (letrozole) or chemotherapy (docetaxel), consistent with the selective survival of tumor-initiating cells posttreatment. We confirmed an increased expression of mesenchymal markers, including vimentin (VIM) in cytokeratin-positive epithelial cells metalloproteinase 2 (MMP2), in two separate sets of postletrozole vs. pretreatment specimens. Taken together, these data provide supporting evidence that the residual breast tumor cell populations surviving after conventional treatment may be enriched for subpopulations of cells with both tumor-initiating and mesenchymal features. Targeting proteins involved in EMT may provide a therapeutic strategy for eliminating surviving cells to prevent recurrence and improve long-term survival in breast cancer patients.
KW - CD44/CD24 markers
KW - Gene expression signature
KW - Mesenchymal features
KW - Treatment resistance
KW - Tumor-initiating cancer cells
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U2 - 10.1073/pnas.0905718106
DO - 10.1073/pnas.0905718106
M3 - Article
C2 - 19666588
AN - SCOPUS:69549131213
VL - 106
SP - 13820
EP - 13825
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 33
ER -