TY - JOUR
T1 - Dephosphorylation of Bcl-2 by protein phosphatase 2A results in apoptosis resistance
AU - Simizu, Siro
AU - Tamura, Yuki
AU - Osada, Hiroyuki
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2004/3
Y1 - 2004/3
N2 - The anti-apoptotic protein, Bcl-2 was phosphorylated at the Ser-87 residue in normal human blood cells, while it was not phosphorylated in tumor cells. We identified protein phosphatase 2A (PP2A) as a Bcl-2-associated phosphatase that is responsible for dephosphorylation of Bcl-2 in tumor cell lines. Treatment of the tumor cells with a PP2A inhibitor resulted in the appearance of Bcl-2 phosphorylation at Ser-87. This observation suggests that Bcl-2 is constitutively phosphorylated, but is immediately dephosphorylated by PP2A in tumors. Phosphorylation of Bcl-2 protein at the Ser-87 residue resulted in a reduction in anti-apoptotic function in human tumor cell lines. Thus, not only the expression level, but also the dephosphorylation status may have important implications for the oncogenic activity of Bcl-2.
AB - The anti-apoptotic protein, Bcl-2 was phosphorylated at the Ser-87 residue in normal human blood cells, while it was not phosphorylated in tumor cells. We identified protein phosphatase 2A (PP2A) as a Bcl-2-associated phosphatase that is responsible for dephosphorylation of Bcl-2 in tumor cell lines. Treatment of the tumor cells with a PP2A inhibitor resulted in the appearance of Bcl-2 phosphorylation at Ser-87. This observation suggests that Bcl-2 is constitutively phosphorylated, but is immediately dephosphorylated by PP2A in tumors. Phosphorylation of Bcl-2 protein at the Ser-87 residue resulted in a reduction in anti-apoptotic function in human tumor cell lines. Thus, not only the expression level, but also the dephosphorylation status may have important implications for the oncogenic activity of Bcl-2.
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U2 - 10.1111/j.1349-7006.2004.tb02214.x
DO - 10.1111/j.1349-7006.2004.tb02214.x
M3 - Article
C2 - 15016329
AN - SCOPUS:1842866996
VL - 95
SP - 266
EP - 270
JO - Cancer Science
JF - Cancer Science
SN - 1347-9032
IS - 3
ER -