These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Galectin-1-mediated apoptosis in mycosis fungoides: the roles of CD7 and cell surface glycosylation.
    Author: Roberts AA, Amano M, Felten C, Galvan M, Sulur G, Pinter-Brown L, Dobbeling U, Burg G, Said J, Baum LG.
    Journal: Mod Pathol; 2003 Jun; 16(6):543-51. PubMed ID: 12808059.
    Abstract:
    Sezary cells, the malignant T cells in mycosis fungoides/Sezary syndrome, resist a variety of apoptosis-inducing agents, a feature that contributes to the poor response to therapy in mycosis fungoides. Galectin-1 is a mammalian lectin that triggers T cell apoptosis. For T cells to be susceptible to galectin-1-induced apoptosis, the T cells must express specific glycoprotein receptors, such as CD7, that bear the specific oligosaccharides recognized by galectin-1. Because Sezary cells are characteristically CD7(-), lack of CD7 expression has been proposed to render Sezary cells resistant to galectin-1-induced death. However, the role played by aberrant cell surface glycosylation in resistance of Sezary cells to galectin-1 has not been examined. In this study, we demonstrated abundant galectin-1 in mycosis fungoides skin lesions, indicating that Sezary cells are exposed to galectin-1 in vivo. To determine specific characteristics of Sezary cells that contribute to galectin-1 resistance, we assessed CD7 expression and cell surface glycosylation of Sezary cells in mycosis fungoides lesions and of four Sezary T cell lines. Sezary cells in primary lesions and Sezary T cell lines demonstrated a characteristic "glycotype" with sialylated core 1 O-glycans that promote galectin-1 resistance. Expression of CD7 was necessary but not sufficient for galectin-1-induced death of Sezary cell lines. In addition, CD7(-) Sezary cell lines, and Sezary cells within mycosis fungoides lesions, expressed galectin-1, whereas CD7-positive Sezary cell lines did not express galectin-1. We propose that both loss of CD7 expression and altered cellular glycosylation contribute to apoptosis resistance of malignant T cells in mycosis fungoides.
    [Abstract] [Full Text] [Related] [New Search]