PKC mediates 12(S)-HETE-induced cytoskeletal rearrangement in B16a melanoma cells.

Abstract

The fatty acid 12(S)-HETE may be a new second messenger capable of activating PKC. In tumor cells 12(S)-HETE stimulates cytoskeleton-dependent cellular responses such as adhesion and spreading. Analysis of 12(S)-HETE effects on B16a melanoma cell cytoskeleton revealed reversible rearrangement of microtubules, microfilaments, the actin-binding proteins, vinculin, myosin heavy (MHC) and light chains (MLC), as well as bundling of vimentin intermediate filaments. The alterations in microfilaments and intermediate filaments occurred very rapidly, i.e., 5 min after exposure of tumor cells to 12(S)-HETE. The 12(S)-HETE-induced cytoskeletal alterations were accompanied by centrifugal organelle-translocation. Interestingly, MLC exhibited clear association with the cytoplasmic organelles. Biochemical analysis of the 12(S)-HETE effect indicated a PKC-mediated reversible hyperphosphorylation of MLC, vimentin, and a 130 kD cytoskeletal-associated protein. Optimal effects were obtained after 5 min treatment with 12(S)-HETE at 0.1 microM concentration. 12(S)-HETE pretreatment induced tumor cell spreading on a fibronectin matrix which required the intactness of all three major cytoskeletal components. The spreading process was dependent upon the activity of PKC. Our data suggest that 12(S)-HETE is a physiological stimulant of PKC. Further, it induces rearrangement of the cytoskeleton of tumor cells in interphase resulting in the stimulation of cytoskeleton-dependent cell activity such as spreading.

• Authors: J Timar, D Tang, R Bazaz, M M Haddad, V A Kimler, J D Taylor, K V Honn
• Journal: Cell motility and the cytoskeleton (Cell Motil Cytoskeleton) Vol. 26 Issue 1 Pg. 49-65 ( 1993) ISSN: 0886-1544 [Print] United States
• PMID: 8221907 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Actins
• Cytoskeletal Proteins
• Fibronectins
• Hydroxyeicosatetraenoic Acids
• Phospholipids
• Vimentin
• Vinculin
• 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid
• Protein Kinases
• Myosins
• Calcium

Topics

• 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid
• Actin Cytoskeleton (chemistry, drug effects, ultrastructure)
• Actins (analysis)
• Animals
• Calcium (pharmacology)
• Cell Movement (physiology)
• Cytoskeletal Proteins (metabolism, physiology)
• Cytoskeleton (chemistry, drug effects, ultrastructure)
• Dose-Response Relationship, Drug
• Fibronectins (analysis)
• Fluorescent Antibody Technique
• Hydroxyeicosatetraenoic Acids (pharmacology)
• Immunohistochemistry
• Intermediate Filaments (chemistry, drug effects, ultrastructure)
• Melanoma, Experimental (chemistry, pathology, ultrastructure)
• Mice
• Myosins (analysis)
• Organelles (physiology, ultrastructure)
• Phospholipids (pharmacology)
• Phosphorylation
• Protein Kinases (pharmacology, physiology)
• Skin Neoplasms (chemistry, pathology, ultrastructure)
• Tumor Cells, Cultured
• Vimentin (analysis)
• Vinculin (analysis)