Investigating the Role of CTCs with Stem/EMT-like Features in Metastatic Breast Cancer Patients Treated with Eribulin Mesylate

Abstract

We herein aimed to assess the effect of eribulin mesylate on the cancer stem cell (CSC)/EMT-like phenotype of CTCs, and to investigate the prognostic role of CTC detection and monitoring for eribulin-treated BC patients. Peripheral blood was obtained at baseline (n = 42 patients) and 8 days after treatment initiation (C1D8: n = 22), and on disease progression (PD: n = 26). PBMCs cytospins were immunofluorescently stained for Cytokeratins/ALDH1/TWIST1/DAPI and analyzed via Ariol microscopy. CTCs were detected in 33.3%, 27.3%, and 23.1% of patients at baseline, C1D8, and PD, respectively. Accordingly, partial-EMT+ CTCs represented 61.3%, 0%, and 37.5% of total CTCs, whereas the CSC-like phenotype was consistently expressed by 87.5%, 75%, and 91.7% of CTCs at the respective time points. Interestingly, the CSC+/partial-EMT+ subset prevailed at baseline, but it was eradicated on C1D8 and resurged again during PD. CTC detection at baseline was associated with reduced PFS (p = 0.007) and OS (p = 0.005), and was an independent risk factor for death (HR: 3.779, p = 0.001; multivariate analysis). The CSC+/partial-EMT+ CTCs emerged as the only subset with adverse prognostic significance, while CTC monitoring during eribulin therapy improved the prediction of disease progression. These results indicate that resistant CTC subsets persevere eribulin treatment and highlight the prognostic implications of CTC analyses for eribulin-treated BC patients.

Gene expression markers in peripheral blood and outcome in patients with platinum‐resistant ovarian cancer: A study of the European GANNET53 consortium

“…42 One of the few studies examining the immediate phenotypic change in CTCs caused by chemotherapy found that CTCs with EMTlike features disappeared 8 days after treatment with eribulin, a nontaxane inhibitor of microtubule dynamics, but re-appeared at disease progression, while the number of epithelial-like CTCs was not altered. 43 In that study, immunofluorescent staining of the various cell populations allowed not only an enumeration, but also an allocation of concomitantly existing subpopulations. A limitation of our study and of many molecular studies in general is that it is not possible to discern between subpopulations of cells, because all cells are lysed and all analytes are pooled.…”

“…In lung cancer cell lines, Nakamichi et al observed that G could induce E‐cadherin protein expression, revert EMT, and thereby overcome acquired resistance to treatment 42 . One of the few studies examining the immediate phenotypic change in CTCs caused by chemotherapy found that CTCs with EMT‐like features disappeared 8 days after treatment with eribulin, a non‐taxane inhibitor of microtubule dynamics, but re‐appeared at disease progression, while the number of epithelial‐like CTCs was not altered 43 . In that study, immunofluorescent staining of the various cell populations allowed not only an enumeration, but also an allocation of concomitantly existing subpopulations.…”

Multigene Profiling of Circulating Tumor Cells in Esophageal Squamous Cell Carcinoma Identifies Prognostic Cancer Driver Genes Associated with Epithelial-Mesenchymal-Transition Progression and Chemoresistance

“…Characterized as hybrid EMT or biphenotypic, this intermediate state between the epithelial and mesenchymal phenotypes exhibits the highest metastatic potential [31,32]. In ESCC, biphenotypic and mesenchymal CTCs are dominant subtypes, with epithelial markers (EpCAM and CK8/18/19) and mesenchymal markers (TWIST1 and VIM) identifying 58.9% (76/129) biphenotypic CTCs and 32.6% (42/129) mesenchymal CTCs [33].…”

Shake It Up Baby Now: The Changing Focus on TWIST1 and Epithelial to Mesenchymal Transition in Cancer and Other Diseases

“…TWIST1 induced a CSC phenotype in CRC cells that was responsible for irinotecan resistance [124]. Circulating breast cancer cells shared EMT and CSC markers and were resistant to eribulin mesylate [125]. However, as mentioned above, ovarian cancer stem cells are chemoresistant, but unlike most tumors, the CD44+ CSC population is decidedly epithelial in nature [120].…”