Please use this identifier to cite or link to this item:
https://doi.org/10.1371/journal.pone.0017179
Title: | HAMLET binding to ?-actinin facilitates tumor cell detachment | Authors: | Trulsson M. Yu H. Gisselsson L. Chao Y. Urbano A. Aits S. Mossberg A.-K. Svanborg C. |
Keywords: | alpha actinin alpha actinin 1 alpha actinin 4 alpha lactalbumin beta1 integrin F actin focal adhesion kinase 1 human alpha lactalbumin made lethal to tumor cell ion channel mitogen activated protein kinase 1 small interfering RNA unclassified drug actin actinin beta1 integrin cell extract focal adhesion kinase HAMLET complex, human lactalbumin oleic acid peptide amino acid sequence article binding site cell adhesion cell proliferation cell structure cell survival cell viability controlled study enzyme phosphorylation human human cell immunoprecipitation in vitro study molecular mechanics polyacrylamide gel electrophoresis protein binding protein cross linking protein domain protein expression protein isolation protein localization protein protein interaction signal transduction tumor cell biological model cell adhesion cell death chemical structure chemistry drug effect enzymology metabolism molecular genetics neoplasm pathology protein analysis protein binding protein transport tumor cell line Actinin Actins Amino Acid Sequence Antigens, CD29 Binding Sites Cell Adhesion Cell Death Cell Extracts Cell Line, Tumor Cell Survival Focal Adhesion Protein-Tyrosine Kinases Humans Lactalbumin Models, Biological Models, Molecular Molecular Sequence Data Neoplasms Oleic Acids Peptides Protein Binding Protein Interaction Mapping Protein Transport Signal Transduction |
Issue Date: | 2011 | Citation: | Trulsson M., Yu H., Gisselsson L., Chao Y., Urbano A., Aits S., Mossberg A.-K., Svanborg C. (2011). HAMLET binding to ?-actinin facilitates tumor cell detachment. PLoS ONE 6 (3) : e17179. ScholarBank@NUS Repository. https://doi.org/10.1371/journal.pone.0017179 | Rights: | Attribution 4.0 International | Abstract: | Cell adhesion is tightly regulated by specific molecular interactions and detachment from the extracellular matrix modifies proliferation and survival. HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a protein-lipid complex with tumoricidal activity that also triggers tumor cell detachment in vitro and in vivo, suggesting that molecular interactions defining detachment are perturbed in cancer cells. To identify such interactions, cell membrane extracts were used in Far-western blots and HAMLET was shown to bind ?-actinins; major F-actin cross-linking proteins and focal adhesion constituents. Synthetic peptide mapping revealed that HAMLET binds to the N-terminal actin-binding domain as well as the integrin-binding domain of ?-actinin-4. By co-immunoprecipitation of extracts from HAMLET-treated cancer cells, an interaction with ?-actinin-1 and -4 was observed. Inhibition of ?-actinin-1 and ?-actinin-4 expression by siRNA transfection increased detachment, while ?-actinin-4-GFP over-expression significantly delayed rounding up and detachment of tumor cells in response to HAMLET. In response to HAMLET, adherent tumor cells rounded up and detached, suggesting a loss of the actin cytoskeletal organization. These changes were accompanied by a reduction in ?1 integrin staining and a decrease in FAK and ERK1/2 phosphorylation, consistent with a disruption of integrin-dependent cell adhesion signaling. Detachment per se did not increase cell death during the 22 hour experimental period, regardless of ?-actinin-4 and ?-actinin-1 expression levels but adherent cells with low ?-actinin levels showed increased death in response to HAMLET. The results suggest that the interaction between HAMLET and ?-actinins promotes tumor cell detachment. As ?-actinins also associate with signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, additional ?-actinin-dependent mechanisms are discussed. © 2011 Trulsson et al. | Source Title: | PLoS ONE | URI: | https://scholarbank.nus.edu.sg/handle/10635/162055 | ISSN: | 19326203 | DOI: | 10.1371/journal.pone.0017179 | Rights: | Attribution 4.0 International |
Appears in Collections: | Elements Staff Publications |
Show full item record
Files in This Item:
File | Description | Size | Format | Access Settings | Version | |
---|---|---|---|---|---|---|
10_1371_journal_pone_0017179.pdf | 7.75 MB | Adobe PDF | OPEN | None | View/Download |
This item is licensed under a Creative Commons License