HCELL Is the Major E- and L-selectin Ligand Expressed on LS174T Colon Carcinoma Cells

Abstract

When confined to a primary site (early stage disease), the five-year survival rate from colon cancer is ϳ90%. However, when disseminated from primary sites (metastatic), survival drops precipitously to 8%. These dramatic survival statistics underscore the need to define the pathobiology of the metastatic process to devise novel interventions to prevent or inhibit colon cancer spread. Hematogenous metastasis occurs as a highly regulated cascade of events, initiated by the escape of tumor cells from the primary site into the blood stream and culminating in the formation of secondary colonies in distant organs. This process critically involves the binding of circulating colon cancer cells to the endothelium of target tissue(s) under fluid shear conditions, as well as the dynamic formation of leukocyte/cancer cell emboli, each of which are directed by selectin-selectin ligand interactions.The selectin family of adhesion molecules, E-, P-, and L-selectin, are Ca 2ϩ -dependent lectins that bind sialofucosylated carbohydrate structures, the prototypes of which are sialyl Lewis X (sLe x ) and sialyl Lewis A (sLe a ) (1, 2). E-and P-selectin are typically inducible endothelial molecules (P-selectin is also expressed on activated platelets), and L-selectin expression is restricted to leukocytes (3). There are multiple reports that tumor cell expression of E-selectin ligand(s) promotes the metastatic spread of numerous cancer types in vivo, including colon cancer (4 -10). Colon carcinoma cells also tether and roll under dynamic flow conditions on E-selectin purified and immobilized on plastic (11, 12), as well as E-selectin presented by cytokine-stimulated human umbilical vein endothelial cells (HUVEC) 2 (11-13). Independently, L-selectin has been shown to promote colon cancer metastasis in vivo (14), presumably mediated by the physical association of leukocytes with tumor cells resulting in leukocyte-colon cancer cell emboli (15, 16). Although expression of E-selectin ligand(s) on tumor cells itself promotes metastasis, one model holds that selectins work cooperatively to promote the spread of cancer; leukocyte L-selectin engagement of relevant tumor ligand(s) mediates the formation of leukocyte-tumor aggregates, which possess heightened binding capacity to endothelium in an E-selectindependent manner (16).Colon carcinoma cells express selectin ligands, and there is abundant evidence that selectin-dependent adhesive events are central to the metastatic process (4 -10,14). However, these selectin ligands have yet to be fully characterized or identified other than by general classifications (e.g. mucins). We recently identified the sialofucosylated hematopoietic cell E-and L-selectin ligand (HCELL) glycoform of CD44 on the LS174T colon carcinoma cell line and demonstrated its function as a high affinity E-and L-selectin ligand using the blot rolling assay (17, 18). However, these studies did not specifically address the relative contribution(s) of HCELL to the observed potent E-and L-selectin ligand activity of intact LS174...

Introducing α(1,2)‐linked fucose into hepatocarcinoma cells inhibits vasculogenesis and tumor growth

“…Fluorography of samples from total cell extract, flowthrough and fucose-eluted fractions is shown in Figure 6b. Again, no 35 S-labeled proteins could be seen in eluted fractions (Elu) from parental cells, while three major proteins of 50, 80 and 150 kDa were retained on UEA-1 column from FUT1-expressing cell extract. These data are in accordance with those from MAL staining and GC-MS analysis (see Fig.…”

“…35 HepG2 cells, which also interact with both E-and L-selectin and express two major sLe x -protein carriers of 80-90 and 150 kDa (this study), has been reported to express the CD44 proteins. 36 It is therefore tempting to investigate whether our two KM93-positive proteins are related to the CD44.…”

“…For this purpose, parental and FUT1-transduced cells were metabolically labeled with 35 Smethionine and detergent extracts were prepared and subjected to UEA-1 affinity chromatography. As shown in Figure 6a, a significant amount of 35 S-labeled material from FUT1-expressing cells is retained on the column and is specifically eluted with 0.1 M fucose, whereas roughly no radioactivity is eluted from the column loaded with HepG2 cell extract, consistent with results from Figure 1a, indicating that these cells do not express a(1,2)-fucosylated glycoconjugates.…”

L-selectin-mediated Lymphocyte-Cancer Cell Interactions under Low Fluid Shear Conditions

“…Isolated PBMC were Ͼ90% T cells (CD3ϩ cells) and expressed L-selectin as determined by immunofluorescent staining and flow cytometry using a Beckman-Coulter model Cytomics FC 500 MPL (Fullerton, CA Shear-dependent Binding Assays-Cell-cell interactions were studied by growing cells in standard tissue culture-treated 6-well plates. A circular parallel plate flow chamber apparatus (GlycoTech, Gaithersburg, MD) with internal flow chamber dimensions of 2 ϫ 0.5 ϫ 0.025 cm was mounted over the unfixed live cell monolayer (HNSCC cells) or fixed cell monolayer (KG1a and LS174T cells) within a well and sealed using low wall suction as described previously (18,19). The system was then equilibrated with Hanks' balanced salt solution (Invitrogen) supplemented with 10 mM HEPES, pH 7.4, and 2 mM CaCl 2 (binding buffer).…”

The role of adhesion molecules in acute myeloid leukemia and (hemato)oncology: A systematic review

“…Cancer cells characteristically express CD44, and there is increasing evidence that HCELL serves as their major selectin ligand. This finding clarifies the ability of solid tumors to infiltrate bone marrow that is both HCELL and CXCR4 dependent [137][138][139] . Variations in CD44 are reported as cell surface markers for breast cancer stem cells.…”