title: ROCK-regulated cytoskeletal dynamics participate in the inhibitory effect of melatonin on cancer cell migration.
abstract: Cell movement is generated by a driving force provided by dynamic cytoskeletal organization. Two main cytoskeletal-dependent features, essential for migration, are the highly cell polarized structure and focal adhesion complexes. Cell migration and substrate anchorage are finely regulated by external signaling exerted by growth factors and hormones. In particular, the serine threonine kinase activated by the small GTPase Rho, the Rho-associated protein kinase (ROCK), participate in both processes through regulation of actin rearrangements in lamellipodia, filopodia, ruffles, and stress fibers. Melatonin, the main product secreted by the pineal gland has oncostatic properties. In MCF-7 cells, 1 nm melatonin reduces migration and invasiveness through increased expression of two cell surface adhesion proteins, E-cadherin and beta(1)-integrin. In this work, we studied the microfilament and microtubule rearrangements elicited by melatonin in migrating leader MCF-7 cells by a wound-healing assay. Additionally, cell anchorage was estimated by quantification of focal adhesions in MCF-7 cells cultured with melatonin. ROCK participation in the indole effects on anchorage and migration was explored by inhibition of the kinase activity with the specific inhibitor of ROCK, the Y-27632 compound. The results indicate that ROCK participates in the melatonin inhibitory effects on cell migration by changing cytoskeletal organization of leader MCF-7 cells. Also, they indicated that indole increased the number of focal contacts through ROCK. These results support the notion that melatonin inhibits cancer cell invasion and metastasis formation via ROCK-regulated microfilament and microtubule organization that converge in a migration/anchorage switch.
authors.affiliation: Instituto Nacional de Psiquiatría, Departamento de Neurofarmacología, Subdirección de Investigaciones Clínicas, Mexico D.F., Mexico.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Ortíz-López
authors.forename: Sandra
authors.initials: S
authors.lastname: Morales-Mulia
authors.forename: Gerardo
authors.initials: G
authors.lastname: Ramírez-Rodríguez
authors.forename: Gloria
authors.initials: G
authors.lastname: Benítez-King
mesh_terms: D000577:Amides / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D001943:Breast Neoplasms / Q000201:enzymology / Q000473:pathology*; D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D003599:Cytoskeleton / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008550:Melatonin / Q000494:pharmacology*; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D014945:Wound Healing / Q000187:drug effects; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D000577:Amides; D011725:Pyridines; C108830:Y 27632; D054460:rho-Associated Kinases; D008550:Melatonin