Role of the tyrosine phosphatase SHP-1 in K562 cell differentiation

Citation
B. Bruecher-encke et al., Role of the tyrosine phosphatase SHP-1 in K562 cell differentiation, LEUKEMIA, 15(9), 2001, pp. 1424-1432
Citations number
47
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Onconogenesis & Cancer Research
Journal title
LEUKEMIA
ISSN journal
0887-6924 → ACNP
Volume
15
Issue
9
Year of publication
2001
Pages
1424 - 1432
Database
ISI
SICI code
0887-6924(200109)15:9<1424:ROTTPS>2.0.ZU;2-L
Abstract
The erythro-megakaryoblastic leukemia cell line K562 undergoes erythroid or myeloid differentiation in response to treatment with various inducing age nts. We observed that expression of the SH2-containing protein tyrosine pho sphatase SHP-1 was induced upon exposure of K562 cells to differentiating a gents. Under the same conditions, expression of SHP-2, a close relative of SHP-1, and the more distantly related PTP-1B remained unchanged. Induction of SHP-1 expression correlates with dephosphorylation of a specific and lim ited set of tyrosyl phosphoproteins, suggesting that dephosphorylation of t hese proteins may be important for the differentiation process. Importantly , expression of exogenous SHP-1 inhibits K562 proliferation and alters the adhesion properties of these cells, indicating a more differentiated phenot ype. Moreover, SHP-1 is found in a complex with both p210 Bcr-Abl and p190 Bcr-Abl, suggesting that it may regulate Bcr-Abl or Bcr-Abl-associated phos photyrosyl proteins. Our results indicate that induction of SHP-1 expressio n is important for K562 differentiation in response to various inducers and raise the possibility that functional inactivation of SHP-1 may play a rol e in progression to blast crisis in chronic myelogenous leukemia.