Open AccessEpCAM-independent isolation of circulating tumor cells with epithelial-to-mesenchymal transition and cancer stem cell phenotypes using ApoStream® in patients with breast cancer treated with primary systemic therapy
Author(s) -
Fanny Le Du,
Takeo Fujii,
Kumiko Kida,
Darren W. Davis,
Minjeong Park,
Diane D. Liu,
Weiguo Wu,
Mariana Chávez-MacGregor,
Carlos H. Barcenas,
Vicente Valero,
Debu Tripathy,
James M. Reuben,
Naoto T. Ueno
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0229903
Subject(s) - circulating tumor cell , epithelial–mesenchymal transition , epithelial cell adhesion molecule , breast cancer , cd44 , medicine , cancer stem cell , metastasis , cancer , metastatic breast cancer , cancer research , vimentin , pathology , oncology , biology , immunohistochemistry , cell , genetics
Background Tumor cells with a mesenchymal phenotype and/or cancer stem-like cells (CSCs) are known to contribute to metastasis and drug resistance. Circulating tumor cells (CTCs) undergoing epithelial-mesenchymal transition (EMT) and CTCs reflecting a dedifferentiated CSC phenotype may not be detected using only an anti-EpCAM antibody to capture them. We used an antibody-independent CTC enrichment platform, ApoStream ® , which does not rely on any antibody, including anti-EpCAM, to capture EMT- and CSC-CTCs in breast cancer patients who received neoadjuvant chemotherapy and correlated them to pathological complete response (pCR). Methods Blood samples from newly diagnosed breast cancer patients were prospectively collected before neoadjuvant chemotherapy (T 0 ), after chemotherapy but before surgery (T 1 ), and after surgery (T 2 ) and processed using ApoStream. CTCs detected were stained with additional markers to define 3 CTC subsets with the following phenotypes: epithelial CTCs (CK+, EpCAM+ or E-cadherin+), EMT-CTCs (β-catenin+ or vimentin+), and CSC-CTCs (CD44+ and CD24 low ). Results We enrolled 55 patients, 47 of which had data for analysis. EMT-CTCs were detected in 57%, 62%, and 72% and CSC-CTCs in 9%, 22%, and 19% at the T 0 , T 1 , and T 2 time points, respectively. Counts of epithelial (P = 0.225) and EMT (P = 0.522) phenotypes of CTCs at T 0 did not significantly predict pCR. Moreover, no correlation between CTC count change and pCR was demonstrated. Conclusions ApoStream was successful in detecting EMT-CTCs among patients after neoadjuvant chemotherapy. However, EMT-/CSC-CTC counts did not correlate with pCR. Due to the small sample size and heterogeneity of this patient population, further study in a larger cohort of molecularly homogeneous patients is warranted.