Dataset Information

Caveolae mediate growth factor-induced disassembly of adherens junctions to support tumor cell dissociation.

ABSTRACT: Remodeling of cell-cell contacts through the internalization of adherens junction proteins is an important event during both normal development and the process of tumor cell metastasis. Here we show that the integrity of tumor cell-cell contacts is disrupted after epidermal growth factor (EGF) stimulation through caveolae-mediated endocytosis of the adherens junction protein E-cadherin. Caveolin-1 and E-cadherin closely associated at cell borders and in internalized structures upon stimulation with EGF. Furthermore, preventing caveolae assembly through reduction of caveolin-1 protein or expression of a caveolin-1 tyrosine phospho-mutant resulted in the accumulation of E-cadherin at cell borders and the formation of tightly adherent cells. Most striking was the fact that exogenous expression of caveolin-1 in tumor cells that contain tight, well-defined, borders resulted in a dramatic dispersal of these cells. Together, these findings provide new insights into how cells might disassemble cell-cell contacts to help mediate the remodeling of adherens junctions, and tumor cell metastasis and invasion.

SUBMITTER: Orlichenko L

PROVIDER: S-EPMC2754928 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Caveolae mediate growth factor-induced disassembly of adherens junctions to support tumor cell dissociation.

Orlichenko Lidiya L Weller Shaun G SG Cao Hong H Krueger Eugene W EW Awoniyi Muyiwa M Beznoussenko Galina G Buccione Roberto R McNiven Mark A MA

Molecular biology of the cell 20090729 19

Remodeling of cell-cell contacts through the internalization of adherens junction proteins is an important event during both normal development and the process of tumor cell metastasis. Here we show that the integrity of tumor cell-cell contacts is disrupted after epidermal growth factor (EGF) stimulation through caveolae-mediated endocytosis of the adherens junction protein E-cadherin. Caveolin-1 and E-cadherin closely associated at cell borders and in internalized structures upon stimulation w ...[more]

PMID: 19641024

Similar Datasets

Project description:During endochondral ossification, the cartilage is surrounded by a layer of cells that constitute the perichondrium. Communication between osteoblasts in the perichondrium via N-cadherin adherens junctions is essential for endochondral bone growth. We observed that adherens junction molecule N-cadherin and its interacting partners p120, ?-catenin and PTEN are expressed by cells present in the perichondrium. To study if N-cadherin mediated adherens junctions play a role in mediating signal transduction events during bone development, we utilized MC3T3E1 preosteoblasts plated at sub confluent (low) and confluent (high) densities to mimic adherens junction formation. When MC3T3E1 cells were plated at high density we observed an increase in phosphorylation of AKTSer473 and its downstream target GSK3Ser9, which coincided with an increase in Osterix, Osteomodulin and Osteoglycin gene expression. Using immunofluorescence, we identified N-cadherin, p120 and ?-catenin localized at the membrane of MC3T3E1 cells. Treatment of confluent MC3T3E1 cells with an N-cadherin junction inhibitor-EGTA and a PI3K inhibitor LY294002 resulted in reduction of phosphorylation levels of AKT and GSK3 and expression of Osterix, Osteomodulin and Osteoglycin. Furthermore, utilizing an N-cadherin blocking antibody resulted in reduced AKT signaling and Osterix gene expression, suggesting that osteoblast junction formation is linked to activation of PI3K signaling, which leads to osteoblast differentiation. To further explore the strength of this linkage, we utilized a conditional knockout approach using Dermo1cre to delete ?-catenin and PTEN, two important proteins known to be essential for adherens junctions and PI3K signaling, respectively. In the absence of ?-catenin, we observed a decrease in adherens junctions and AKT signaling in the perichondrium. PTEN deletion, on the other hand, increased the number of cells expressing N-cadherin in the perichondrium. These observations show that N-cadherin mediated junctions between osteoblasts are needed for osteoblast gene transcription.

Project description:Background: Negative-pressure wound therapy has become widely available in modern chronic wound cares. Accelerated keratinocyte (HaCaT cell) movements and decreased E-cadherin expressions induced by the applied negative pressure gradient of 125 mmHg (NP) have been reported in previous studies. However, the molecular mechanism for E-cadherin regulations under NP remains unexplored. We highlighted the signal transduction involved in NP-induced E-cadherin regulation for keratinocytes in the study. Results: Microarray results showed that catenin 1 (CTNND1) gene, the gene encoding the p120-catenin (p120ctn) in cell-cell junctions, was significantly (p = 0.0005) upregulated in HaCaT cells under NP for 12 hours in comparison with those at ambient pressure (AP). Cell fractionations and immunoblotting data showed that NP increased p120ctn phosphorylation, and resulted in p120ctn translocation from the plasma membrane to the cytoplasm. Fluorescent stains suggested that NP diminished the co-localization of p120ctn and E-cadherin on the plasma membrane. Similar phenomenon was also observed in the cells with overexpressed p120ctn at NP. Interestingly, overexpression of dN- p120ctn, a deletion mutant of p120ctn without the N-terminal phosphorylation sites, restored the adherens junctions (AJ) at NP. Knockdown of p120ctn with lentiviral small hairpin RNA not only diminished E-cadherin expressions but also accelerated cell movement at AP. Conclusions: Phosphorylation of p120ctn is endowed to respond rapidly to NP and contributes to the AJ disassembly. This NP-induced E-cadherin downregulation can possibly accelerate wound-healing process. Conclusions: Phosphorylation of p120ctn is endowed to respond rapidly to NP and contributes to the AJ disassembly. This NP-induced E-cadherin downregulation can possibly accelerate wound-healing process. HaCaT cells under negative pressure (NP) gradient of 125 mmHg for 12 hours in comparison with those at ambient pressure (AP) were tested for RNA extraction and hybridization on Affymetrix microarrays. The experiments have been biological replicated three times. The differential expression gene between NP and AP were selected and validated with qPCR method.

Dataset Information

Caveolae mediate growth factor-induced disassembly of adherens junctions to support tumor cell dissociation.

Publications

Caveolae mediate growth factor-induced disassembly of adherens junctions to support tumor cell dissociation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets