Claudin 1 inhibits cell migration and increases intercellular adhesion in triple-negative breast cancer cell line

Abstract

Triple-negative "claudin 1 low" subtype represents around 15% of breast cancer and displays poor prognosis. The loss of claudin 1 is correlated with increased invasiveness and higher recurrence of the disease. Claudin 1 constitutes the backbone of the tight junction and is involved in cell-cell adhesion and migration processes. However, studies showed a controversial role of claudin 1 in cell migration. In this study, we aimed to clarify the effect of claudin 1 on migration of mesenchymal triple-negative breast cancer cells (TNBC). We reported that transient over expression of claudin 1 in MDA-MB-231 and Hs578T "claudin 1 low" TNBC cells inhibited cell migration using wound healing and transwell migration assays. In order to investigate more specifically the involvement of claudin 1, we generated stable MDA-MB-231 clones overexpressing claudin 1. Interestingly, the level of claudin 1 was correlated to the inhibition of cell migration and to the increase of cellcell aggregation associated with enhanced formation of β-catenin adherens junction and occludin tight junction. Finally, we reported for the first time the key role of claudin 1 in the inhibition of cell migration process associated with the disappearance of stress fibers. These data suggest that re-expression of claudin 1 could be a promising strategy for regulating the migration of TNBC which no longer express claudin 1. Keywords Triple negative breast cancer • Claudin 1 • Migration • Stress fiber • Cell junctions Abbreviations CLDN1 Claudin 1 TJ Tight junction EMT Epithelial-mesenchymal transition MSL Mesenchymal-stem-like DOCK Dedicator of cytokinesis AJ Adherent junction ZO-1 Zonula occludens-1 TNBC Triple negative breast cancer FCS Fetal calf serum PDZ-domain-binding-motif PSD95, DlgA, ZO-1 domain binding motif CSRP2 Cysteine-rich-protein 2 Electronic supplementary material The online version of this article (

AB186 Inhibits Migration of Triple-Negative Breast Cancer Cells and Interacts with α-Tubulin

“…MDA-MB-231 (6 × 10 5 cells/well) and Hs578T (2 × 10 5 cells/well) were seeded in 6-well plates for 24 h until 90% of confluence. A scratch was made with a 200 µL pipette tip through the cell monolayer and cells were treated with Δ2-TGZ or AB186 for 0, 3, 6, or 12 h. Wound closure was observed as previously described [ 35 ].…”

“…The upper chamber of insert containing cells was placed into the lower chamber supplemented with 10% FCS as chemoattractant. After 9 h of treatment, the migrating cells were analyzed as described previously [ 35 ].…”

Context-Dependent Roles of Claudins in Tumorigenesis

“…For example, claudin-18 was shown to suppress the abnormal motility of lung epithelial cells by inhibiting the PI3K/PDK1/Akt signaling pathway, while claudin-6 promoted cell migration through activation of the same signaling pathway ( 35 , 86 ). Claudin-1 overexpression brings morphological changes and increases the intercellular adhesion through the disappearance of stress fibers, resulting in the migration inhibition of breast cancer mesenchymal-stem-like subtype cells ( 87 ). However, claudin-1 has also been found to participate in cancer cell migration through activation of focal adhesion kinase (FAK), another nonreceptor protein tyrosine kinase that controls fundamental cellular processes, including migration under physiological or disease conditions ( 88 ).…”

Troglitazone Derivatives Induce Early Modifications of the Cytoskeleton and Inhibition of Migration in Breast Cancer Cells

“…MDA-MB-231 (6.10 5 cells/well) and Hs578T (2.10 5 cells/well) were seeded in 6-well plates for 24 h until 90 % of confluence. A scratch was made with a 200 µL pipette tip through the cell monolayer and cells were treated with Δ2-TGZ or AB186 for 0, 3, 6 or 12 h. Wound closure was observed as previously described [23].…”

“…The upper chamber of insert containing cells was placed into the lower chamber supplemented with 10% FCS as chemoattractant. After 9 h of treatment, the migrating cells were analyzed as described previously [23].…”