title: Cyclin D1 regulates cellular migration through the inhibition of thrombospondin 1 and ROCK signaling.
abstract: Cyclin D1 is overexpressed in human tumors, correlating with cellular metastasis, and is induced by activating Rho GTPases. Herein, cyclin D1-deficient mouse embryo fibroblasts (MEFs) exhibited increased adhesion and decreased motility compared with wild-type MEFs. Retroviral transduction of cyclin D1 reversed these phenotypes. Mutational analysis of cyclin D1 demonstrated that its effects on cellular adhesion and migration were independent of the pRb and p160 coactivator binding domains. Genomewide expression arrays identified a subset of genes regulated by cyclin D1, including Rho-activated kinase II (ROCKII) and thrombospondin 1 (TSP-1). cyclin D1(-/-) cells showed increased Rho GTP and ROCKII activity and signaling, with increased phosphorylation of LIM kinase, cofilin (Ser3), and myosin light chain 2 (Thr18/Ser19). Cyclin D1 repressed ROCKII and TSP-1 expression, and the migratory defect of cyclin D1(-/-) cells was reversed by ROCK inhibition or TSP-1 immunoneutralizing antibodies. cyclin E knockin to the cyclin D1(-/-) MEFs rescued the DNA synthesis defect of cyclin D1(-/-) MEFs but did not rescue either the migration defect or the abundance of ROCKII. Cyclin D1 promotes cellular motility through inhibiting ROCK signaling and repressing the metastasis suppressor TSP-1.
authors.affiliation: Thomas Jefferson University, Department of Cancer Biology, Kimmel Cancer Center, Bluemle Building, Rm 1050, 233 South 10th St, Philadelphia, PA 19107, USA.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Li
authors.forename: Chenguang
authors.initials: C
authors.lastname: Wang
authors.forename: Xuanmao
authors.initials: X
authors.lastname: Jiao
authors.forename: Yinan
authors.initials: Y
authors.lastname: Lu
authors.forename: Maofu
authors.initials: M
authors.lastname: Fu
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Quong
authors.forename: Chip
authors.initials: C
authors.lastname: Dye
authors.forename: Jianguo
authors.initials: J
authors.lastname: Yang
authors.forename: Maozheng
authors.initials: M
authors.lastname: Dai
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Ju
authors.forename: Xueping
authors.initials: X
authors.lastname: Zhang
authors.forename: Anping
authors.initials: A
authors.lastname: Li
authors.forename: Peter
authors.initials: P
authors.lastname: Burbelo
authors.forename: E Richard
authors.initials: ER
authors.lastname: Stanley
authors.forename: Richard G
authors.initials: RG
authors.lastname: Pestell
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000737:chemistry / Q000172:deficiency / Q000378:metabolism*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D005347:Fibroblasts / Q000166:cytology; D005786:Gene Expression Regulation; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D009154:Mutation / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D022502:Stress Fibers / Q000378:metabolism; D019700:Thrombospondin 1 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D054460:rho-Associated Kinases
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16; D047908:Intracellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D019700:Thrombospondin 1; D019938:Cyclin D1; D004247:DNA; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D018844:Cyclin-Dependent Kinases