Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P17931 (galectin-3)
 2,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of galectin-3 (formerly known as IgE-binding protein or Mac-2) in rat bone marrow (BM) was investigated by FACS, immunocytochemical and immunoblot analysis. The functional significance of rat recombinant galectin-3 on mouse recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF)-driven proliferation of macrophage progenitors and gene transcription was further examined. Immunocytochemical analysis of in situ BM sections demonstrated galectin-3 in myelopoietic cells and surrounding stroma, whereas erythropoietic and lymphopoietic environments essentially lacked galectin-3 expression. FACS analysis demonstrated that incubation of freshly isolated BMC with lactose, a competing ligand for galectin-3 binding to glycoconjugates, decreased binding of antigalectin antibodies to cells primarily expressing the myeloid antigen recognized by mAb His-54. Similarly, lectin-mediated binding of exogenous galectin-3 to myeloid lineage cells was also demonstrated. Immunoblot analysis of BM eluates demonstrated galectin-3 both in the extracellular matrix and in a lactose elutable form, bound to the surface of BMC. [3H]Thymidine incorporation studies on BMC cultured in the presence of galectin-3 demonstrated suppression of GM-CSF-induced proliferation by galectin-3. In addition, differential display analysis of immediate early gene expression in BMC cultured in the presence of galectin-3 revealed a 76.2% inhibition of GM-CSF-induced gene transcription by galectin-3 assessed by the number of PCR-fragments generated. Our data suggest a role for galectin-3 in the organization of myelopoietic compartments in rat BM and regulation of the action of growth factors on myelopoietic precursor cells.
 ...
PMID:Galectin-3 inhibits granulocyte-macrophage colony-stimulating factor (GM-CSF)-driven rat bone marrow cell proliferation and GM-CSF-induced gene transcription. 924 34

Osteopontin (OPN) expression in tumors is associated with more aggressive tumor growth; however, several studies have suggested that OPN as a host protein can regulate tumor growth as well. OPN is produced by macrophages and T cells, and reportedly modifies macrophage function. Here, we have investigated the effect of OPN on macrophage function, and its role in host defense against tumor growth. OPN deficient (-/-) and wild-type (WT) peritoneal macrophages were assessed for their ability to mediate cytotoxicity of tumor cells. Thioglycollate-elicited peritoneal exudate cells (PEC) were stimulated in vitro with interferon-gamma and lipopolysaccharide. [(3)H]Thymidine-labeled ras-transformed tumor cells were then added and (3)H release and nitrite accumulation were measured. OPN -/- PEC exhibited as much as a 70% reduction in cytotoxicity as compared to WT PEC. Tumor cell OPN status, on the other hand, had little effect on the extent of cytotoxicity. Production of nitrite by the PEC correlated with their capacity to kill tumor cells. L-929 cells, which are relatively resistant to nitric oxide-induced cytotoxicity and sensitive to that effected by TNF-alpha, were killed equally well by wild-type and OPN-deficient PEC, suggesting that the effect of OPN is not mediated through TNF-alpha. No difference was seen in the cytotoxicity of resident macrophages from mice of different genotypes, indicating that the defect in the OPN-deficient macrophages may result from altered differentiation in vivo. In support of this idea, we show that the expression of the macrophage markers F4/80 in peritoneal cells and of Mac-2 in spleen cells is altered in OPN -/- mice as compared to WT. These data support the hypothesis that host-derived osteopontin may inhibit tumor growth and provide a mechanism for this effect.
 ...
PMID:Impaired anti-tumor cytotoxicity of macrophages from osteopontin-deficient mice. 1505 10

Galectin-3 is a 30-kDa galactose-binding protein member of the galectin family. Galectin-3 is involved in multiple intracellular and extracellular biological functions, e.g. interactions with laminin and with nucleic acids. This latter property is consistent with the presence of 3. serum-response factor-like domain at the amino-terminal part of the protein. Galectin-3 expression is upregulated during serum-mediated induction of proliferation. In order to examine the role of galectin-3 in breast cancer cell proliferation, we examined in this study the influence of antisense galectin-3 complementary DNA stable transfection on the in vitro thymidine incorporation of human breast cancer MDA-MB435 cells. Two stable transfectants, clones 5.24 and 5.29, were selected based both on the presence of a complete CMV promoter-antisense galectin-3 cDNA cassette as assayed by polymerase chain reaction, and on efficient down-regulation of galectin-3 protein expression as determined by Western blotting. Thymidine incorporation experiments showed that both clones were characterized by significantly decreased values of DNA incorporation compared to wild-type transfectants (55 to 68%, and 71 to 82% of the control clone values). Our data demonstrate for the first time that galectin-3 decreases thymidine incorporation in breast cancer cells. The mechanism underlying this property of galectin-3 and its importance during breast cancer development remain to be elucidated.
 ...
PMID:Antisense galectin-3 alters thymidine incorporation in human MDA-MB435 breast cancer cells. 2152 9