L-Selectin Expression is Influenced by Phosphatase Activity in Chronic Lymphocytic Leukemia.
Cytometry B Clin Cytom
; 96(2): 149-157, 2019 03.
Article
en En
| MEDLINE
| ID: mdl-30729673
ABSTRACT
BACKGROUND:
Adhesion receptors have important role in cellular invasiveness and L-selectin is a primary determinant in the binding of chronic lymphocytic leukemia (CLL) cells to several glycated proteins on endothelial cells. We investigated L-selectin expression on CLL cells and explored the mechanisms that lead to their shedding.METHODS:
Surface and soluble L-selectin expression levels were studied by flow cytometry and immunoassay, respectively. Magnetically isolated B-cells from patients and controls were investigated for total and protein phosphatase-2A activities. Flow cytometry of permeabilized cells was utilized for the determination of phosphorylated mitogen-activated protein kinase (pp38MAPK) and surface tumor necrosis factor alpha-converting enzyme expression (TACE).RESULTS:
In CLL patients elevated absolute lymphocyte cell counts, high soluble and low surface L-selectin expression were observed. Similarly, TACE surface expression was significantly lower on B-CLL cells compared to normal B-cells. Both total phosphatase and protein phosphatase-2A activities were also significantly lower in B-CLL cells compared to normal B-cells and we found a consequently higher level of pp38 MAPK in B-CLL cells. Based on in vitro experiments a MAPK inhibitor could attenuate the phosphatase inhibitor's effect on L-selectin shedding.CONCLUSIONS:
The lower phosphatase activity detectable in chronic lymphocytic leukemia, results in a downstream signaling cascade with subsequent reduction of surface L-selectin expression and this effect is mediated by enhanced phosphorylation of p38MAPK and an altered TACE expression. © 2019 The Authors. Cytometry Part B Clinical Cytometry published by Wiley Periodicals, Inc. on behalf of International Clinical Cytometry Society.Palabras clave
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Leucemia Linfocítica Crónica de Células B
/
Monoéster Fosfórico Hidrolasas
/
Selectina L
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Cytometry B Clin Cytom
Año:
2019
Tipo del documento:
Article
País de afiliación:
Hungria