Cell-Matrix Interactions in Breast Carcinoma Invasion.
Abstract
The alpha 6 beta 4 integrin is a laminin 5 receptor expressed on the basal, basement membrane-apposed surface of ductal breast epithelial cells. In contrast to all other known integrins, alpha 6 beta 4 is concentrated in hemidesmosomes, adhesive junctions which connect the basement membrane to the intracellular keratin cytoskeleton. In virtually all cases of human breast cancer analyzed, alpha 6 beta 4 has been found to be diffusely distributed at the cell surface instead of being concentrated in hemidesmosomes. Our previous studies have indicated that alpha 6 beta 4 promotes the assembly of hemidesmosomes by interacting, via a specific region of the large unique cytoplasmic domain of the beta 4 subunit, with cytoskeletal elements of hemidesmosomes. We have observed that ligation of the EGF-R or EGF-R/Neu heterodimer promotes the association of the Src-family kinase Fyn with alpha 6 beta 4 and begun to map the sequences of Fyn and beta 4 required for the interaction. Ligation of the EGF-R or EGF-R/Neu heterodimer causes tyrosine phosphorylation of the beta 4 tail and disassembly of hemidesmosomes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1998
- Accession Number
- ADA346658
Entities
People
- Anna M. Curatola
Organizations
- NYU Langone Health