Cyclin D1 triggers autonomous growth of breast cancer cells by governing cell cycle exit.
Cyclin D1 controls G1-associated processes, including G0-to-G1 and G1-to-S transitions. This study demonstrates a novel aspect of cyclin D1 as a regulator of the transition between G1 and G0. Overexpression of cyclin D1 in MCF7 breast tumor cells resulted in a continued proliferation under low-serum conditions, whereas nonoverexpressing cells ceased to grow. This difference in growth was due to a reduced exit from G1 to G0 in cyclin D1-overexpressing cells. Our data therefore suggest a model in which cyclin D1 overexpression in tumor cells is responsible for hyperproliferation under growth factor-deprived conditions.
Zwijsen
R M
RM
Department of Tumor Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
Klompmaker
R
R
Wientjens
E B
EB
Kristel
P M
PM
van der Burg
B
B
Michalides
R J
RJ
D001943:Breast Neoplasms / Q000473:pathology*; D002453:Cell Cycle / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D003470:Culture Media; D019938:Cyclin D1; D016213:Cyclins / Q000235:genetics / Q000502:physiology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D015513:Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D010766:Phosphorylation; D016160:Retinoblastoma Protein / Q000378:metabolism; D013752:Tetracycline / Q000494:pharmacology; D015533:Transcriptional Activation / Q000187:drug effects; D014162:Transfection; D014407:Tumor Cells, Cultured
D003470:Culture Media; D016213:Cyclins; D015513:Oncogene Proteins; D016160:Retinoblastoma Protein; D019938:Cyclin D1; D013752:Tetracycline