PMID: 11912172Mar 26, 2002Paper

Bag1 proteins regulate growth and survival of ZR-75-1 human breast cancer cells

Cancer Research
Masafumi KudohJohn C Reed

Abstract

Bag1 proteins bind heat shock protein M(r) 70,000 (Hsp 70) family molecular chaperones and regulate diverse pathways involved in cell proliferation, apoptosis, and stress responses. Four isoforms of Bag1 can be produced from a single gene in humans, including a nuclear-targeted long version (Bag1L)and a shorter cytosolic isoform (Bag1). Because overexpression of Bag1and Bag1L has been reported in breast cancers, we explored the effects of Bag1 and Bag1L on the growth of ZR-75-1 human breast cancer cells cultured in vitro and in tumor xenograft models using immunocompromised mice. Cells stably transfected with expression plasmids encoding either Bag1 or Bag1L displayed comparable rates of growth in cultures containing 10% serum, compared with control-transfected ZR-75-1 cells. In contrast, ZR-75-1 cells stably expressing mutants of Bag1 or Bag1L, which lack the COOH-terminal domain (DeltaC) required for heat shock protein M(r) 70,000 binding, displayed retarded growth rates. When cultured without serum, the viability of control-transfected, as well as Bag1DeltaC- and Bag1LDeltaC-expressing, cells declined with time, whereas Bag1- and Bag1L-overexpressing ZR-75-1 cells survived for over a week in culture. Caspase protease activat...Continue Reading

Related Concepts

Related Feeds

Apoptotic Caspases

Apoptotic caspases belong to the protease enzyme family and are known to play an essential role in inflammation and programmed cell death. Here is the latest research.

Apoptosis

Apoptosis is a specific process that leads to programmed cell death through the activation of an evolutionary conserved intracellular pathway leading to pathognomic cellular changes distinct from cellular necrosis

Adhesion Molecules in Health and Disease

Cell adhesion molecules are a subset of cell adhesion proteins located on the cell surface involved in binding with other cells or with the extracellular matrix in the process called cell adhesion. In essence, cell adhesion molecules help cells stick to each other and to their surroundings. Cell adhesion is a crucial component in maintaining tissue structure and function. Discover the latest research on adhesion molecule and their role in health and disease here.