Constitutive overexpression of cyclin D1 in human breast epithelial cells does not prevent G1 arrest induced by deprivation of epidermal growth factor. Academic Article uri icon

Overview

abstract

  • Non-transformed human breast epithelial cell line MCF10A is dependent on exogenous epidermal growth factor (EGF) for continued growth. Complete G1 arrest was rapidly induced following EGF deprivation. The cell cycle arrest was accompanied by increased levels of p27KIP1, a cyclin-dependent kinase inhibitor, and reduced level of cyclin D1. This was associated with strong inhibition of cyclin-dependent kinase 2 and cyclin D1-associated kinase activities. Introduction of exogenous cyclin D1 into MCF10A (MCF10AD1) cells resulted in an accelerated cell growth rate but did not confer colony-forming capacity. Cell cycle arrest was still achieved in MCF10AD1 cells following EGF deprivation. In the great majority of MCF10AD1 clones, accumulation in G1 phase was accompanied by reduced cyclin D1 and increased p27KIP1 protein levels. In two clones where cyclin D remained unchanged during G1 arrest, it was found that more cyclin D1 protein was bound to p27KIP1. The data demonstrate that ectopic expression of cyclin D1 alone could not transform MCF10A cells nor was it sufficient to prevent G1 arrest induced by EGF deprivation.

publication date

  • June 1, 1999

Research

keywords

  • Breast
  • CDC2-CDC28 Kinases
  • Cell Cycle Proteins
  • Cyclin D1
  • Epidermal Growth Factor
  • Epithelial Cells
  • G1 Phase
  • Tumor Suppressor Proteins

Identity

Scopus Document Identifier

  • 0032867174

Digital Object Identifier (DOI)

  • 10.1023/a:1006217413089

PubMed ID

  • 10517171

Additional Document Info

volume

  • 55

issue

  • 3