Abstract
In epithelial cells β-catenin plays a critical role as a component of the cell-cell adhesion apparatus and as a coactivator of the TCF/LEF (T-cell transcription factor/lymphoid enhancer binding factor) family of transcription factors. Deregulation of β-catenin has been implicated in the malignant transformation of cells of epithelial origin. However, a function for β-catenin in hematologic malignancies has not been reported. β-Catenin is not detectable in normal peripheral blood T cells but is expressed in T-acute lymphoblastic leukemia cells and other tumor lines of hematopoietic origin and in primary lymphoid and myeloid leukemia cells. β-Catenin function was examined in Jurkat T-acute lymphoblastic leukemia cells. Overexpression of dominant-negative β-catenin or dominant-negative TCF reduced β-catenin nuclear signaling and inhibited Jurkat proliferation and clonogenicity. Similarly, these constructs inhibited proliferation of K562 and HUT-102 cells. Reduction of β-catenin expression with β-catenin antisense down-regulated adhesion of Jurkat cells in response to phytohemagglutinin. Incubation of Jurkat cells with anti-Fas induced caspase-dependent limited proteolysis of β-catenin N- and C-terminal regions and rapid redistribution of β-catenin to the detergent-insoluble cytoskeleton, concomitant with a marked decline in nuclear β-catenin signaling. Fas-mediated apoptosis was potentiated by inhibition of β-catenin nuclear signaling. The data suggest that β-catenin can play a significant role in promoting leukemic cell proliferation, adhesion, and survival.
Original language | English (US) |
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Pages (from-to) | 982-990 |
Number of pages | 9 |
Journal | Blood |
Volume | 100 |
Issue number | 3 |
DOIs | |
State | Published - Aug 1 2002 |
Externally published | Yes |
ASJC Scopus subject areas
- Biochemistry
- Immunology
- Hematology
- Cell Biology