Adhesion and migration of extracellular matrix-stimulated breast cancer.
BACKGROUND
Extracellular matrix (ECM) components, such as vitronectin and fibronectin, have been shown to enhance the metastatic potential of breast cancer cells. We hypothesized that ECM binding to integrin receptors on breast cancer cells influenced cellular adhesion and migration.


METHODS
Adhesion assays were performed using breast cancer cell lines MDA-MB-435 and MDA-MB-231 and various concentrations of vitronectin or fibronectin. Migration assays were performed using the same cell lines and invasion chambers with 8 microm pore polycarbonate membranes. Blocking antibodies and specific peptidomimetic inhibitors to integrin receptors were used to identify the integrin subunits reacting with vitronectin and fibronectin.


RESULTS
While both breast cancer cell lines adhered to and migrated toward vitronectin and fibronectin, MDA-MB-435 had a higher maximum binding to vitronectin and MDA-MB-231 had a higher maximum binding to fibronectin. Anti-beta1 antibody inhibited the adhesion and migration of MDA-MB-231 to fibronectin and the adhesion of MDA-MB-231 to vitronectin but had no effect on vitronectin-induced adhesion or migration of MDA-MB-435. The alpha(v)beta3/alpha(v)beta5 antagonist, SB 265123, inhibited MDA-MB-231 and MDA-MB-435 adhesion and migration to vitronectin but had no effect on migration to fibronectin in either cell line.


CONCLUSIONS
We conclude that the integrin subunits beta1, alpha(v)beta3, and alpha(v)beta5 can be involved in breast cancer cell adhesion and migration to vitronectin and fibronectin. Because more than one integrin inhibitor was required to block adhesion or migration in the cell lines studied, breast cancer therapy based on integrin antagonists would most likely require concomitant use of multiple agents.
Bartsch
John E
JE
Department of Surgery, Medical College of Ohio, 3065 Arlington Avenue, Ohio 43614-5807, Toledo, USA.
Staren
Edgar D
ED
Appert
Hubert E
HE
D000085:Acetates / Q000494:pharmacology; D000631:Aminopyridines / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001570:Benzodiazepinones / Q000494:pharmacology; D001943:Breast Neoplasms / Q000503:physiopathology*; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D005109:Extracellular Matrix / Q000502:physiology*; D005260:Female; D005353:Fibronectins / Q000494:pharmacology; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000037:antagonists & inhibitors; D039641:Integrin beta Chains / Q000187:drug effects; D016023:Integrins / Q000037:antagonists & inhibitors; D010446:Peptide Fragments; D019030:Receptors, Vitronectin / Q000037:antagonists & inhibitors; D014407:Tumor Cells, Cultured; D019096:Vitronectin / Q000494:pharmacology
D000085:Acetates; D000631:Aminopyridines; D000911:Antibodies, Monoclonal; D001570:Benzodiazepinones; D005353:Fibronectins; D039302:Integrin alphaVbeta3; D039641:Integrin beta Chains; D016023:Integrins; D010446:Peptide Fragments; D019030:Receptors, Vitronectin; C121648:SB 223245; C121647:SB 265123; D019096:Vitronectin; C064660:integrin alphaVbeta5