Selection of a MCF-7 Breast Cancer Cell Subpopulation with High Sensitivity to IL-1β: Characterization of and Correlation between Morphological and Molecular Changes Leading to Increased Invasiveness

Abstract

Cancer and inflammation are closely related in tumor malignancy prognosis. Breast cancer MCF-7 cells have a poor invasive phenotype, although, under IL-1β stimulus, acquire invasive features. Cell response heterogeneity has precluded precise evaluation of the malignant transition. MCF-7A3 cells were selected for high sensitivity to IL-1β stimulus, uniform expression of CXCR4, and stability of IL1-RI. Structural changes, colony formation ability, proliferation rate, chemotaxis, Matrigel invasion, E-cadherin mRNA expression and protein localization were determined in these cells and in MCF-7 parental cells under the stimulus of IL-1β. Selected MCF-7A3 cells showed a uniform response to IL-1β stimulation increasing features of invasive cells such as scattering, colony formation, proliferation, chemokinesis and invasion. Basal expression of E-cadherin mRNA was higher, and IL-1β stimulus had no further effect at early times of cytokine exposure. Total E-cadherin levels remained unchanged in parental cells, whereas levels decreased, as MCF-7A3 cells became fibroblastoid or scattered. Triton X-100 soluble/insoluble E-cadherin ratios were highly increased in these cells, while, in MCF-7pl cells, ratios could not be correlated with morphology changes. MCF-7A3 cells uniform response to IL-1β allowed characterization of changes induced by the cytokine that had not been assessed when using heterogeneous cell lines.

GPER signalling in both cancer-associated fibroblasts and breast cancer cells mediates a feedforward IL1β/IL1R1 response

“…Upon IL1β stimulation, breast cancer cells acquire certain features of an invasive phenotype as the loss of cell-cell contact, the acquisition of a fibroblastoid cytoarchitecture and cell scattering 14 15 36 . Nicely recapitulating the abovementioned results, medium collected from E2 and G-1 treated CAFs induced a fibroblast-like phenotype (as evaluated by the polarity index) in SkBr3 cells transfected with a shRNA and exposed to E2 and G-1, but not in SkBr3 cells transfected with a shGPER ( Fig.…”

“…High levels of IL1β within the tumor microenvironment have been associated with increased recurrence and metastasis in breast cancer 4 9 12 13 . In this regard, it has been shown that breast cancer cells exposed to IL1β may acquire an invasive phenotype through diverse structural changes as the loss of cell-cell contact, the acquisition of a fibroblastoid cytoarchitecture and cell scattering 14 15 . Moreover, a positive correlation between IL1β levels and estrogens was found in breast tissue biopsies and the ability of estrogens to stimulate IL1β production was recently reported both in vitro and in breast cancer xenografts 10 11 .…”

Tamoxifen Rechallenge Decreases Metastatic Potential but Increases Cell Viability and Clonogenicity in a Tamoxifen-Mediated Cytotoxicity-Resistant Subline of Human Breast MCF7 Cancer Cells

“…Human breast MCF7 cancer cells are commonly used for studying the biology and drug resistance development process of ER + (or luminal A subtype-like) breast cancer (Comşa et al, 2015). Although MCF7 was originally thought to be a monoclonal cell line, it was recently discovered as a population of breast cancer cells (mostly ER + ) with high levels of molecular heterogeneity (Leung et al, 2010;Pérez-Yépez et al, 2012;Khan et al, 2017;Roden et al, 2018). In this study, we identified a subpopulation (or a subline) of MCF7 cells (i.e., the ERα low /β low -p53 −/low -HER2 low -Smac low -XIAP hi -Bcl-2β + MCF7-TAM12.5 cells), which exhibit higher therapeutic tolerance (i.e., cell death resistance, during primary challenge) and have differential metastatic potential and clonogenic responses (upon rechallenge) against tamoxifen.…”

99mTc-HYNIC-(tricine/EDDA)-FROP peptide for MCF-7 breast tumor targeting and imaging

“…MCF-7 parental cells also maintain the expression of epithelial markers, such as E-cadherin, β-catenin and cytokeratin 18 (CK18) and other specific molecular markers of natural epithelial layers, such as claudins and zona occuldens protein 1 (ZO-1), among other proteins that constitute the intercellular junctions. Furthermore, MCF-7 are mesenchymal markers negative, these markers are including vimentin and smooth muscle actin (SMA) [ 28 , 29 ]. FROP-1 peptide was identified by phage display technology by Sabine Zitzmann research group in 2007 [ 13 ].…”