The FX Enzyme Is a Functional Component of Lymphocyte Activation

Eshel, Rinat; Besser, Michal J.; Zanin, Alexandra; Sagi‐Assif, Orit; Witz, Isaac P.

doi:10.1006/cimm.2001.1872

Cited by 14 publications

(21 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Electrophoretic transfer of proteins from the polyacrylamide gel to nitrocellulose (Schleicher and Schull) was performed by a minitransblot electrophoretic cell (Bio-Rad TM ) at 100 V for 1.5 h. After transfer, the nitrocellulose membrane was incubated at room temperature with 3% bovine serum albumin (BSA) in TBS-Tween for 30 min to block free binding sites on the membrane. The blocked nitrocellulose membrane was incubated 2 h at room temperature with rabbit polyclonal antibodies against Pyst2-L and with mouse monoclonal antibodies against GAPDH as previously described (Eshel et al, 2001;Levy-Nissenbaum et al, 2003c). Erk was detected by rabbit antibodies against Erk1/2 (Santa Cruz Biotechnology, Santa Cruz, CA, USA).…”

Section: Sds-polyacrylamide Gel Electrophoresis and Western Blottingmentioning

confidence: 99%

See 1 more Smart Citation

Dual-specificity phosphatase Pyst2-L is constitutively highly expressed in myeloid leukemia and other malignant cells

et al. 2003

Self Cite

View full text Add to dashboard Cite

Northern blotting confirmed previous results indicating that the mitogen-activated protein kinase (MAPK) phosphatase Pyst2-L was highly expressed in leukocytes obtained from acute myeloid leukemia (AML) patients. High levels of Pyst2-L mRNA were expressed in bone marrow (BM) and peripheral leukocytes from nine AML and acute lymphoblastic leukemia (ALL) patients. BM from healthy individuals expressed very low levels of Pyst2-L. Whereas high levels of Pyst2-L mRNA and protein were detected in several leukemia cell lines, Pyst2-L mRNA was detected neither in 33/34 samples of normal peripheral blood mononuclear cells (PBMC) nor in leukocyte fractions enriched with CD34 þ cells. Certain solid tumor and lymphoblastoid cell lines expressed high levels of Pyst2-L mRNA. In view of the association of Pyst2-L to MAPK signaling cascades, we tested if cell activation, a process involving MAPK signaling, influences Pyst2-L expression. Indeed, activation of T cells and endothelial cells increased Pyst2-L in these cells. Furthermore, TPA, a known MAPK activator, induces the expression of both Pyst2-L mRNA as well as the Pyst2-L protein in leukemia cells. This induction was partially inhibited by PD098059, an Mek1/2-specific inhibitor. Based on the results of this and previous studies, we hypothesize that the high levels of Pyst2-L detected in the active state of AML and ALL diseases and in other types of cancer reflect an altered MAPK signaling pathway in such malignant processes. This alteration may be the result of a failed attempt to counter the constitutive activation of MAPK in transformed cells or alternatively, may represent the activated state of such cells.

show abstract

Section: Sds-polyacrylamide Gel Electrophoresis and Western Blottingmentioning

confidence: 99%

“…Finally, the nitrocellulose strips were washed five times for 5 min each with TBS-Tween. The bands were visualized by chemoluminescence-ECL reactions as previously described (Eshel et al, 2001;Levy-Nissenbaum et al, 2003c).…”

Section: Sds-polyacrylamide Gel Electrophoresis and Western Blottingmentioning

confidence: 99%

Dual-specificity phosphatase Pyst2-L is constitutively highly expressed in myeloid leukemia and other malignant cells

et al. 2003

Self Cite

View full text Add to dashboard Cite

show abstract

“…Previous studies from our laboratory demonstrated that the FX enzyme is involved in the biosynthesis of sLe-x in activated T or B cells (13). In head and neck squamous cell carcinomas, the FX enzyme plays a key role in the biosynthesis of selectin ligands such as sialyl Lewis-a (sLe-a) and in the interaction of these cancer cells with endothelial cells (14,15).…”

Section: Introductionmentioning

confidence: 99%

“…In head and neck squamous cell carcinomas, the FX enzyme plays a key role in the biosynthesis of selectin ligands such as sialyl Lewis-a (sLe-a) and in the interaction of these cancer cells with endothelial cells (14,15). In lymphocytes, as well as in head and neck squamous cell carcinomas, the FX enzyme is regulated by outside-in signaling (13,14).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Tumor-Microenvironment Interactions

Zipin

Israeli-Amit²,

Meshel³

et al. 2004

Cancer Research

Self Cite

View full text Add to dashboard Cite

These transfection experiments also indicated that manipulating the levels of the FX enzyme affected global cellular fucosylation and altered the interaction of colorectal cancer cells with some extracellular matrix components such as fibronectin. We also found that highly metastatic colorectal cancer variants express higher levels of FX and of sialyl Lewis-a than low metastatic variants originating in the same tumors. These results lead us to hypothesize that the FX enzyme controls the capacity of colorectal cancer to extravasate and form metastasis. If this hypothesis will be confirmed the FX enzyme could become a target molecule for metastasis prevention.

show abstract

Characterization of the dual‐specificity phosphatase PYST2 and its transcripts

Levy-Nissenbaum

Sagi‐Assif

Witz

2003

Genes Chromosomes & Cancer

Self Cite

View full text Add to dashboard Cite

PYST2 is a member of a structurally homologous subfamily of MAP kinase phosphatases. A computer-based analysis of the PYST2 locus revealed that it harbors two alternative open reading frames promoted by two conserved promoter regions. Using Northern blot analysis and reverse transcription-polymerase chain reaction followed by sequencing and alignment of the products, we confirmed the existence of two mRNAs that were transcribed from this genomic region. Western blot analysis indicated that these transcripts were translated. Functional bioinformatic analysis of both transcripts revealed that exon 2 exists in only one of the PYST2 transcripts, designated PYST2-L, and has the consensus elements of the phosphatase catalytic domain (PCD). We found that the translation from the PYST2-L transcript starts 46 codons upstream from the (already-known) PYST2 5' sequence. Furthermore, the existence of three PYST2-L transcripts was indicated. These transcripts differ only in their 5' untranslated regions (5'UTRs). Unlike PYST2-L, the other mRNA (PYST2-S) is devoid of any known PCD. Analysis of the predicted Pyst2-S protein revealed the presence of the vertebrate metallothionein signature I, the mammalian defensin, and the zinc-containing alcohol dehydrogenase motifs. These motifs might confer on this protein the ability to sense changes in the cellular environment. From these and previous results, we speculate that Pyst2-S may function as a negative regulator of Pyst2-L.

show abstract

The FX Enzyme Is a Functional Component of Lymphocyte Activation

Cited by 14 publications

References 26 publications

Dual-specificity phosphatase Pyst2-L is constitutively highly expressed in myeloid leukemia and other malignant cells

Dual-specificity phosphatase Pyst2-L is constitutively highly expressed in myeloid leukemia and other malignant cells

Tumor-Microenvironment Interactions

Characterization of the dual‐specificity phosphatase PYST2 and its transcripts

Contact Info

Product

Resources

About