6401

SELE

selectin E;SELE;selectin E

CD62 antigen-like family member E|E-selectin|ELAM-1|endothelial adhesion molecule 1|endothelial leukocyte adhesion molecule 1|leukocyte endothelial cell adhesion molecule 2|leukocyte-endothelial cell adhesion molecule 2

1q24.2

protein-coding

Endothelial cell adhesion molecules (CAMs) are important in tumorigenesis and host defense mechanism. Their status in breast cancer with regard to nodal invasion is not yet known. Hence we looked at the expression of three important CAMs: VCAM, ICAM and E-selectin. A downregulation of all these CAMs was noted in node positive breast cancer in comparison to node negative cases. This suggests shedding of these molecules in cases with nodal metastasis which might help the tumor cells to escape the host defense mechanism. On multi-variate analysis, VCAM alone emerged as an independent predictor of nodal metastasis.

To investigate the possible roles of E-selectin and its ligand, Sialyl Lewis X, in lymph node metastasis of invasive micropapillary carcinoma of the breast, 100 cases of invasive micropapillary carcinoma and 97 cases of invasive ductal carcinoma were analyzed immunohistochemically for the expression of E-selectin and Sialyl Lewis X, along with CD34, to measure the microvessel density of invasive micropapillary carcinoma. We found that the number of E-selectin-positive vessels was greater in invasive micropapillary carcinoma than in invasive ductal carcinoma, and it was significantly correlated with the histological grade, the number of positive lymph nodes, and the microvessel density of invasive micropapillary carcinoma. The Sialyl Lewis X expression of invasive micropapillary carcinoma was higher than that of invasive ductal carcinoma, which was also associated with lymph node metastasis. In invasive micropapillary carcinoma, the Sialyl Lewis X expression was predominantly in the stroma-facing surface of the cell clusters and the adjacent stroma, while in invasive ductal carcinoma it was largely intracytoplasmic or intercellular. These findings suggested that E-selectin and Sialyl Lewis X might play an important role in lymph node metastasis in invasive micropapillary carcinoma. The expression pattern of Sialyl Lewis X in invasive micropapillary carcinoma suggested that the reversal of cell polarity of invasive micropapillary carcinoma might be as an important factor for the morphogenesis and possibly the pathogenesis, especially their higher rates of lymph node metastasis.

metastasis formation is a complex process still poorly understood. Previous work in a colon cancer xenograft model showed that E(ndothelial) and P(latelet) selectins mediate spontaneous metastasis to the lungs. To investigate the functional role of selectins in breast cancer, human DU4475 breast cancer cells were injected subcutaneously into pfp-/-rag2-/- mice and in all their selectin-deficient variants (EP-/-, E-/- and P-/-). Pfp-/-rag2-/- mice as well as all their selectin-deficient variants developed primary tumours and spontaneous metastases. Compared with the wild-type mice, disseminated tumours cells were significantly lower (74% reduction, P=0.046) in the bone marrow of selectin-deficient mice. Pfp-/-rag2-/- mice developed significantly higher numbers of lung metastases (6644.83+/-741.77) than the E-/- (4053.33+/-112.58; P=0.002) and the EP-/- pfp-/-rag2-/- mice (4665.65+/-754.50; P<0.001). The results indicate that E- and P-selectins play a role in spontaneous metastasis formation both into bone marrow and lungs. However, spontaneous metastasis was not completely abrogated, hence additional cell adhesion molecules must be involved in the metastatic spread.

Adhesion molecules play an important role in tumor metastasis. E-selectin can support adhesion of colon cancer cells through the recognition of specific carbohydrate ligands. High levels of soluble E-selectin (sE-selectin) had been reported in melanoma and some epithelial tumors, especially in colorectal carcinoma. The concentrations of the sE-selectin were investigated in serum samples of 64 patients (32 men and 32 women) with colorectal cancer and 16 healthy subjects. Median age was 57 (range 20-75). Nineteen patients were staged as Dukes D, 9 of whom had liver metastasis. Serum levels of sE-selectin were determined by ELISA. In the study group, sE-selectin concentrations (mean+/-SE, ng/ml) were not significantly elevated, compared with the control group (41.09+/-4.57 in the control group and 43.80+/-1.88 in patients, p>0.05). Mean sE-selectin levels were 42.27+/-1.85 in non-metastatic and 47.42+/-4.57 in metastatic patients (p>0.05). Serum concentrations of sE-selectin were significantly elevated in patients with colorectal cancer metastatic to liver (59.07+/-7.52) in comparison to other patients without liver metastasis (p=0.013). There were no significant correlations between sE-selectin levels and other parameters such as age of patients, stage of disease, histopathological differentiation or localization of primary tumor. Elevated sE-selectin levels were confirmed as correlating with poor overall survival. In conclusion, sE-selectin concentrations may not be used as a predictive marker of metastasis in colorectal carcinoma, but high levels of sE-selectin may support diagnosis of liver metastasis.

The extravasation of cancer cells is a key step of the metastatic cascade. Polymorphisms in genes encoding adhesion molecules can facilitate metastasis by increasing the strength of interaction between tumor and endothelial cells as well as impacting other properties of cancer cells. We investigated the Ser128Arg (a561c at the nucleotide level) polymorphism in the E-selectin gene in patients with metastatic colon cancer and its functional significance. Genotyping for a561c polymorphism was performed on 172 cancer patients and on an age-matched control population. The colon cancer group was divided into groups with (M(+)) and without observable metastasis (M(-)). For in vitro functional assays, Huvec transfected cells expressing wild-type (WT) or the S128R variant of E-selectin were established to study in vitro binding ability and signal transduction processes of T84 colon cancer cell line. Our results demonstrated that the Arginine(128) allele was more prevalent in the M(+) group than in the M(-) group or normal controls (p < 0.005; odds ratio, 1.56; 95% confidence interval (CI) 1.16-1.92; p < 0.001, odds ratio = 1.65; CI = 1.24-1.99, respectively). In vitro, S128R E-selectin transfected Huvec cells, supported increased adhesion as well as increased cellular signaling of T84 cancer cells compared to WT E-selectin and mock-transfected Huvec cells. These findings suggest that the E-selectin S128R polymorphism can functionally affect tumor-endothelial interactions as well as motility and signaling properties of neoplastic cells that may modulate the metastatic phenotype.

Colorectal cancer (CRC) is one of the most common cancers of the gastrointestinal tract and the fourth cause of cancers death in the world. Soluble adhesion molecules (CAMs) are thought to have an important role in host defense against carcinogenesis. They are biomarkers of inflammation and indicators of the immune response to tumors. The study included 40 CRC patients without remote metastases and 24 control subjects. Serum concentrations of sE-selectin, sICAM and sVCAM in patients with CRC were investigated by ELISA method. The level of the sCAMs decreased significantly after radical tumor resection. Preoperative serum concentrations of sICAM and sVCAM in CRC patients were significantly higher compared to the control group, whereas there were no differences regarding serum sE-selectin. Serum levels of sE-selectin, sICAM and sVCAM correlated significantly with each other. There was a significant correlation of serum levels of sICAM-1 and sVCAM-1, but not sE-selectin, with TNM stage and lymph node involvement. No significant relationship was found between serum concentrations of sICAM-1, sVCAM-1 and sE-selectin in CRC patients and patients' age or gender. Our findings suggest that an improved understanding of the mechanisms of membrane shedding of sICAM, sVCAM and sE-selectin is required to delineate their role in tumor progression.

AIM: To study the expression levels of E- selectin, integrin beta1 and immunoglobulin superfamily member-intercellular adhesion molecule-1 (ICAM-1) in human gastric carcinoma cells, and to explore the relationship between these three kinds of cell adhesion molecules and gastric carcinoma. METHODS: The serum contents of E-selectin, integrin beta1 and ICAM-1 were detected by enzyme-linked immunosorbent assay (ELISA), in 47 healthy individuals (control group) and in 57 patients with gastric carcinoma (gastric carcinoma group) respectively prior to operation and 7 d after operation. RESULTS: The serum E-selectin, ECAM-1 and integrin beta1 were found to be expressed in both control and gastric carcinoma groups. However, they were highly expressed in patients with gastric carcinoma patients before operation or with unresectable tumours. The expression levels of ICAM-1 and integrin beta1 were significantly higher in gastric carcinoma patients than in controls (P < 0.01). A comparison of the E-selectin levels between the two groups showed statistically insignificant difference (P = 0.64). In addition, the expression levels were all decreased substantially in the postoperative patients subjected to radical resection of the tumours, indicating that the high level expressions of these compounds might be the important factor for predicting the prognosis of these patients. CONCLUSION: Serum E-selectin, ICAM-1 and integrin beta1 expression levels are probably related to the metastasis and relapse of gastric cancer.

OBJECTIVE: To study the significance of E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma (HCC). METHODS: Flow cytometry and immunohistochemistry were used to detect the expression of E-selectin and its ligand-sLeX in both HCC cell lines and human HCC tissues. RESULTS: The positive rate of E-selectin in vascular endothelial cells adjacent to cancer was 67.9% (19/28). The expression of E-selectin in tumors accompanied with emboli or satellite foci was significantly higher than that in tumors without emboli or satellite foci (P<0.05), and it was not related to tumor size, tumor capsule, AFP content, and the degree of differentiation. The positive expression of sLeX in SMMU-7721, PLF/PRF/5 and HepGII cell lines was 7.03%, 63.35% and 97.29% respectively. The positive cells of sLeX mainly distributed in the margin of tumor tissues. The positive expression of sLeX in HCC cells in emboli or invasive tumor tissues was much higher than in Primary foci. CONCLUSION: E-selectin and its ligand-sLeX are closely correlated with the metastasis of HCC.

OBJECTIVES: To explore the effects of E-selectin, ICAM-1 and their ligands on the adhesive metastasis of hepatocellular carcinoma (HCC), and to select possible anti-adhesion drugs for hepatocellular carcinoma metastasis. METHODS: 78 HCC patients were analyzed with the correlation of clinical features to the expression levels of E-selectin, sLeX, sLeA and CD44v6 in the tumor tissue. The adhesion between HepG2 and endothelial cell lines was examined by solid phase adhesion assay in vitro. Two kinds of drugs were accessed for their anti-adhesion ability. RESULTS: The positive rate of E-selectin in vascular endothelia cells adjacent to cancer nest is 70.51%, and which of sLeX, sLeA, CD44v6 within tumor cells is 64.10%, 69.23%, 62.90% respectively. The patients' life span is closely related with the positive expression of sLeX, sLeA, CD44v6 (P = 0.008, 0.001, 0.022). The positive expression of E-selectin, sLeX and sLeA is significantly correlated to portal vein tumor thrombus (PVTT), preoperative extrahepatic metastasis, and satellite foci, but not to the size of tumor and AFP. The level of CD44v6 expression is significantly correlated to patient's survival time. The expression levels of E-selectin and ICAM-1 are remarkably higher after ED25 and ECV304 cell lines be activated. Meanwhile the adhesive ability of HepG2 to endothelial cell is mediated. Dexamethasone, tanshinone IIA are able to block this adhesion at low concentration. CONCLUSION: The expression levels of E-selectin, sLeX, sLeA and CD44v6 are closely correlated with clinical features. E-selectin, ICAM-1 and their ligands are important molecules of hepatocellular carcinoma and endothelial cells to tumor adhesive metastasis. Dexamethasone, tanshinone II A can be hopefully used as anti-adhesion drugs.

cancer metastasis involves multistep adhesive interactions between tumor cells (TCs) and endothelial cells (ECs), but the molecular mechanisms of intercellular communication in the tumor microenvironment remain elusive. Using static and flow coculture systems in conjunction with flow cytometry, we discovered that certain receptors on the ECs are upregulated on melanoma cell adhesion. Direct contact but not separate coculture between human umbilical endothelial cells (HUVECs) and a human melanoma cell line (Lu1205) increased intercellular adhesion molecule 1 (ICAM-1) and E-selectin expression on HUVECs by 3- and 1.5-fold, respectively, compared with HUVECs alone. The nonmetastatic cell line WM35 failed to promote ICAM-1 expression changes in HUVECs on contact. Enzyme-linked immunosorbent assay (ELISA) revealed that EC-TC contact has a synergistic effect on the expression of the cytokines interleukin (IL)-8, IL-6, and growth-related oncogene alpha (Gro-alpha). By using E-selectin cross-linking and beads coated with CD44 immunopurified from Lu1205 cells, we showed that CD44/selectin ligation was responsible for the ICAM-1 up-regulation on HUVECs. Protein kinase Calpha (PKC-alpha) activation was found to be the downstream target of the CD44/selectin-initiated signaling, as ICAM-1 elevation was inhibited by siRNA targeting PKCalpha or a dominant negative form of PKCalpha (PKCalpha DN). Western blot analysis and electrophoretic mobility shift assays (EMSAs) showed that TC-EC contact mediated p38 phosphorylation and binding of the transcription factor SP-1 to its regulation site. In conclusion, CD44/selectin binding signals ICAM-1 up-regulation on the EC surface through a PKCalpha-p38-SP-1 pathway, which further enhances melanoma cell adhesion to ECs during metastasis.

Selectin-mediated interactions in the vasculature promote metastatic spread by facilitating circulating tumor cell binding to selectin-expressing host cells. Therefore, identifying the selectin ligand(s) on tumor cells is critical to the prevention of blood-borne metastasis. A current challenge is to distinguish between structures expressed by circulating tumor cells that can bind selectins in vitro from the functional ligands whose depletion suppresses selectin-dependent binding under flow in vivo. Interestingly, podocalyxin (PODXL), which can bind E- and L-selectin, is upregulated in a number of cancers, including those of the breast, colon, and pancreas. In this work, we show that metastatic pancreatic cancer cells overexpress PODXL compared with nonmalignant pancreatic epithelial cells. We further demonstrate via tissue microarray that 69% of pancreatic ductal adenocarcinomas stain positive for PODXL. In cases of focal expression, positive staining is restricted to the invasive front of primary tumors. By combining immunoblot, immunodepletion, short-hairpin RNA-mediated gene silencing, and flow-based adhesion assays, we evaluated the functional role of sialofucosylated PODXL in selectin-mediated adhesion under flow. Our data indicate that sialofucosylated PODXL is a functional E- and L-selectin ligand expressed by metastatic pancreatic cancer cells, as specific depletion of this molecule from the cell surface significantly interferes with selectin-dependent interactions. Cumulatively, these data support a correlation between sialofucosylated PODXL expression and enhanced binding to selectins by metastatic pancreatic cancer cells and offer additional perspective on the upregulation of PODXL in aggressive cancers.

Haematogenous metastasis of small cell lung cancer (SCLC) is still a poorly understood process and represents the life threatening event in this malignancy. In particular, the rate-limiting step within the metastatic cascade is not yet clearly defined although, many findings indicate, that extravasation of circulating tumour cells is crucially important as most tumour cells within the circulation undergo apoptosis. If extravasation of SCLC tumour cells mimics leukocyte-endothelial interactions, SCLC cells should adhere to E- and P-selectins expressed on the luminal surface of activated endothelium. The adhesion to E- and P-selectin under physiological shear stress with regard to adhesive events, rolling behaviour and rolling velocity was determined in the human SCLC cell lines SW2, H69, H82, OH1 and OH3. OH1 SCLC cells adhered best to recombinant human (rh) E-selectin FC-chimeras and human lung endothelial cells (HPMEC), H82 SCLC cells adhered best to activated human umbilical vein endothelial cells (HUVEC) under physiological shear stress. As OH1 cells had also produced by far the highest number of spontaneous lung metastases when xenografted into pfp/rag2 mice in previous experiments our findings implicate that adhesion of SCLC cells to E-selectin is of paramount importance in SCLC metastasis formation.

metastasis formation is the major reason for the extremely poor prognosis in small cell lung cancer (SCLC) patients. The molecular interaction partners regulating metastasis formation in SCLC are largely unidentified, however, from other tumor entities it is known that tumor cells use the adhesion molecules of the leukocyte adhesion cascade to attach to the endothelium at the site of the future metastasis. Using the human OH-1 SCLC line as a model, we found that these cells expressed E- and P-selectin binding sites, which could be in part attributed to the selectin binding carbohydrate motif sialyl Lewis A. In addition, protein backbones known to carry these glycotopes in other cell lines including PSGL-1, CD44 and CEA could be detected in in vitro and in vivo grown OH1 SCLC cells. By intravital microscopy of murine mesenterial vasculature we could capture SCLC cells while rolling along vessel walls demonstrating that SCLC cells mimic leukocyte rolling behavior in terms of selectin and selectin ligand interaction in vivo indicating that this mechanism might indeed be important for SCLC cells to seed distant metastases. Accordingly, formation of spontaneous distant metastases was reduced by 50% when OH-1 cells were xenografted into E-/P-selectin-deficient mice compared with wild type mice (p = 0.0181). However, as metastasis formation was not completely abrogated in selectin deficient mice, we concluded that this adhesion cascade is redundant and that other molecules of this cascade mediate metastasis formation as well. Using several of these adhesion molecules as interaction partners presumably make SCLC cells so highly metastatic.