Abstract
Dissemination of carcinoma cells requires the pericellular degradation of the extracellular matrix, which is mediated by membrane type 1-matrix metalloproteinase (MT1-MMP). In this article, we report a co-up-regulation and colocalization of MT1-MMP and atypical protein kinase C iota (aPKC iota) in hormone receptor-negative breast tumors in association with a higher risk of metastasis. Silencing of aPKC in invasive breast-tumor cell lines impaired the delivery of MT1-MMP from late endocytic storage compartments to the surface and inhibited matrix degradation and invasion. We provide evidence that aPKC iota, in association with MT1-MMP-containing endosomes, phosphorylates cortactin, which is present in F-actin-rich puncta on MT1-MMP-positive endosomes and regulates cortactin association with the membrane scission protein dynamin-2. Thus, cell line-based observations and clinical data reveal the concerted activity of aPKC, cortactin, and dynamin-2, which control the trafficking of MT1-MMP from late endosome to the plasma membrane and play an important role in the invasive potential of breast-cancer cells.
Original language | English |
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Pages (from-to) | E1872-E1879 |
Number of pages | 8 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 111 |
Issue number | 18 |
DOIs | |
Publication status | Published - 6 May 2014 |
Keywords
- membrane traffic
- actin cytoskeleton
- multi-vesicular body
- MMP14
- EXTRACELLULAR-MATRIX DEGRADATION
- CELL INVASION
- TUMOR-CELLS
- INVADOPODIA FORMATION
- CORTACTIN
- METALLOPROTEINASE
- EXPRESSION
- POLARITY
- OVEREXPRESSION
- METASTASIS