title: Loss of E-cadherin is not a necessity for epithelial to mesenchymal transition in human breast cancer.
abstract: Epithelial to mesenchymal transition (EMT) is typically defined by the acquisition of a spindle cell morphology in combination with loss of E-cadherin and upregulation of mesenchymal markers. However, by studying E-cadherin inactivation in 38 human breast cancer cell lines, we noted that not all cell lines that had undergone EMT had concomitantly lost E-cadherin expression. We further investigated this discrepancy functionally and in clinical breast cancer specimens. Interestingly, reconstitution of wild-type E-cadherin cDNA in a E-cadherin negative cell line that had undergone EMT (MDA-MB-231) did not revert the spindle morphology back to an epithelial morphology. Neither were changes observed in the expression of several markers known to be involved in the EMT process. Similarly, upregulation of E-cadherin via global DNA demethylation in eleven cell lines that had undergone EMT did not induce a change in cell morphology, nor did it alter the expression of EMT markers in these cells. Next, we extracted genes differentially expressed between cell lines that had undergone EMT versus cell lines that had not undergone EMT. Caveolin-1 was identified to be an excellent marker for EMT, irrespective of E-cadherin status (specificity and sensitivity of 100 %). Consistent with our observations in the breast cancer cell lines, expression of Caveolin-1 identified a subset of basal breast cancers, particularly of metaplastic pathology, and only 50 % of these lacked E-cadherin expression. The discrepancy between E-cadherin loss and EMT was thus reproduced in clinical samples. Together, these results indicate that in human breast cancer loss of E-cadherin is not causal for EMT and even not a necessity.
authors: Department of Medical Oncology, Josephine Nefkens Institute, Erasmus University Medical Center-Daniel den Hoed Cancer Center, Rotterdam, The Netherlands. a.hollestelle@erasmusmc.nl
authors: Antoinette
authors: A
authors: Hollestelle
authors: Justine K
authors: JK
authors: Peeters
authors: Marcel
authors: M
authors: Smid
authors: Mieke
authors: M
authors: Timmermans
authors: Leon C
authors: LC
authors: Verhoog
authors: Pieter J
authors: PJ
authors: Westenend
authors: Anouk A J
authors: AA
authors: Heine
authors: Alan
authors: A
authors: Chan
authors: Anieta M
authors: AM
authors: Sieuwerts
authors: Erik A C
authors: EA
authors: Wiemer
authors: Jan G M
authors: JG
authors: Klijn
authors: Peter J
authors: PJ
authors: van der Spek
authors: John A
authors: JA
authors: Foekens
authors: Mieke
authors: M
authors: Schutte
authors: Michael A
authors: MA
authors: den Bakker
authors: John W M
authors: JW
authors: Martens
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D015820:Cadherins / Q000172:deficiency / Q000235:genetics*; D045744:Cell Line, Tumor; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009154:Mutation
chemical_list: D015820:Cadherins