In situ identification of putative cancer stem cells by multiplexing ALDH1, CD44, and cytokeratin identifies breast cancer patients with poor prognosis.
A subset of cells, tentatively called cancer stem cells (CSCs), in breast cancer have been associated with tumor initiation, drug resistance, and tumor persistence or aggressiveness. They are characterized by CD44 positivity, CD24 negativity, and/or ALDH1 positivity in flow cytometric studies. We hypothesized that the frequency or density of these cells may be associated with more aggressive tumor behavior. We borrowed these multiplexed, flow-based methods to develop an in situ method to define CSCs in formalin-fixed paraffin-embedded breast cancer tissue, with the goal of assessing the prognostic value of the presence of CSCs in breast cancer. Using a retrospective collection of 321 node-negative and 318 node-positive patients with a mean follow-up time of 12.6 years, we assessed TMAs using the AQUA method for quantitative immunofluorescence. Using a multiplexed assay for ALDH1, CD44, and cytokeratin to measure the coexpression of these proteins, putative CSCs appear in variable sized clusters and in 27 cases (of 490), which showed significantly worse outcome (log rank P = 0.0003). Multivariate analysis showed that this marker combination is independent of tumor size, histological grade, nodal status, ER-, PR,- and HER2-status. In this cohort, ALDH1 expression alone does not significantly predict outcome. We conclude that the multiplexed method of in situ identification of putative CSCs identifies high risk patients in breast cancer.
Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06520-8023, USA.
Veronique
V
Neumeister
Seema
S
Agarwal
Jennifer
J
Bordeaux
Robert L
RL
Camp
David L
DL
Rimm
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000444:Aldehyde Dehydrogenase / Q000378:metabolism*; D000080924:Aldehyde Dehydrogenase 1 Family; D001943:Breast Neoplasms / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism*; D007633:Keratins / Q000378:metabolism*; D008875:Middle Aged; D014411:Neoplastic Stem Cells / Q000166:cytology*; D011379:Prognosis; D050697:Retinal Dehydrogenase; D012189:Retrospective Studies
D018960:Hyaluronan Receptors; D007527:Isoenzymes; D007633:Keratins; D000080924:Aldehyde Dehydrogenase 1 Family; D000444:Aldehyde Dehydrogenase; C510223:ALDH1A1 protein, human; D050697:Retinal Dehydrogenase