Regulation Of Vascular Cell Adhesion Molecule 1 Research Articles

Shp2 activation in bone marrow microenvironment mediates the drug resistance of B-cell acute lymphoblastic leukemia through enhancing the role of VCAM-1/VLA-4

B-cell acute lymphoblastic leukemia (B-ALL) is immune to the chemotherapy-induced apoptosis as a result of the protection of bone marrow mesenchymal stromal cells (BMSCs). However, the precise underlying mechanism of such protection remains unclear so far. In this experiment, protein tyrosine phosphatase 2 (Shp2), which was encoded by the PTPN11 gene, was highly expressed in BMSCs of the newly diagnosed and the recurrent B-ALL patients. The plasmid-induced (including Shp2 E76K) Shp2 activation in BMSCs (Shp2-activated BMSCs) markedly increased the BMSCs-mediated resistance of leukemia cells both in vitro and in vivo. Additionally, studies in vitro suggested that, the expression of vascular cell adhesion molecule 1 (VCAM-1) was markedly up-regulated in Shp2-activated BMSCs, and VCAM-1 expression in BMSCs of B-ALL patients was negatively correlated with Shp2 expression. Down-regulation of VCAM-1 in BMSCs using siRNA reversed the resistance of CCRF-SB cells mediated by the Shp2-activated BMSCs. As for the molecular mechanism, the PI3K/AKT pathway mediated the regulation of VCAM-1 by Shp2. Blocking the very late antigen-4 (VLA-4) by antibodies in CCRF-SB cells dramatically reversed the resistance of CCRF-SB cells mediated by the Shp2-activated BMSCs, and decreased the adhesion effects of both CCRF-SB cells and BMSCs. In conclusion, Shp2 activation in BMSCs up-regulates VCAM-1 expression through increasing the PI3K/AKT phosphorylation level, and targeting the VCAM-1/VLA-4 signaling may serve as a clinically relevant mechanism to overcome the BMSCs-mediated chemoresistance of B-ALL cells.

VHL promotes immune response against renal cell carcinoma via NF-κB-dependent regulation of VCAM-1.

Vascular cell adhesion molecule 1 (VCAM-1) is an adhesion molecule assigned to the activated endothelium mediating immune cells adhesion and extravasation. However, its expression in renal carcinomas inversely correlates with tumor malignancy. Our experiments in clear cell renal cell carcinoma (ccRCC) cell lines demonstrated that von Hippel Lindau (VHL) loss, hypoxia, or PHD (for prolyl hydroxylase domain-containing proteins) inactivation decreased VCAM-1 levels through a transcriptional mechanism that was independent of the hypoxia-inducible factor and dependent on the nuclear factor κB signaling pathway. Conversely, VHL expression leads to high VCAM-1 levels in ccRCC, which in turn leads to better outcomes, possibly by favoring antitumor immunity through VCAM-1 interaction with the α4β1 integrin expressed in immune cells. Remarkably, in ccRCC human samples with VHL nonmissense mutations, we observed a negative correlation between VCAM-1 levels and ccRCC stage, microvascular invasion, and symptom presentation, pointing out the clinical value of VCAM-1 levels as a marker of ccRCC progression.

MicroRNA-181a-5p Impedes IL-17-Induced Nonsmall Cell Lung Cancer Proliferation and Migration through Targeting VCAM-1

Aim: The contribution of the inflammatory mediator interleukin-17 (IL-17) in nonsmall cell lung cancer (NSCLC) malignancy has been reported in the literature. MicroRNA-181a-5p (miR-181a-5p) acts as a tumor suppressor which can regulate target gene at the posttranscriptional level. Our study aimed to investigate the interaction between IL-17 and miR-181a-5p in NSCLC. Methods: 35 patients with NSCLC and 24 COPD controls were selected and examined in our study. In vitro, H226 and H460 cell lines were exposed to different doses (20, 40, 60, and 80 ng/mL) of IL-17 to examine the effect of IL-17 on miR-181a-5p and vascular cell adhesion molecule 1 (VCAM-1) expression. MiR-181 mimic and miR-181a-5p inhibitor were transfected to explore the regulation of VCAM-1 as well as tumor cell proliferation and migration. Results: miR-181a-5p expression was downregulated, and IL-17 and VCAM-1 expression was upregulated in NSCLC tissues. Furthermore, IL-17 decreased miR-181a-5p expression but increased VCAM-1 expression in H226 and H460 cells. MiR-181 regulated VCAM-1 expression through binding to 3’-UTR sequence. MiR-181 attenuated tumor cell proliferation and migration. IL-17 modulated miR-181a-5p expression through activating NF-κB but not Stat3. Conclusion: Taken together, our data show the regulation of VCAM-1 expression by miR-181a-5p under IL-17 exposure, predicting a potential way for counteracting cancer metastasis.

Abstract 2805: LPA-dependent regulation of VCAM-1 in the ovarian cancer metastatic microenvironment and its impact on mesothelial invasion.

Abstract Ovarian cancer is the leading cause of gynecological cancer deaths in the United States due in large part to the advanced stage of disease at diagnosis. The poor prognosis is attributed to ovarian cancer metastasis to the peritoneal cavity and the accumulation of ascites, which contains elevated levels of several growth factors and cytokines including lysophosphatidic acid (LPA), a bioactive lipid that promotes ovarian cancer proliferation and survival as well as activities relevant to metastasis including migration and invasion. Ovarian cancer metastasis is a complex process that involves attachment to and invasion through the mesothelium and has been associated with vascular cell adhesion molecule 1 (VCAM-1). Previously we have shown that VCAM-1 is preferentially expressed on the mesothelium of patients with ovarian cancer where it functions to promote mesothelial invasion. Inhibition of VCAM-1 function reduces tumor burden and increases survival in a mouse model, implicating VCAM-1 as an important target for the treatment of ovarian cancer. Since LPA promotes ovarian cancer migration and invasion, we questioned whether it also influenced the mesothelium to regulate invasion. Using a co-culture system to measure ovarian cancer cell invasion of the mesothelium, treatment with a VPC51299, a LPA1/3 receptor antagonist, which targets both the cancer cells and the mesothelium, resulted a dose dependent decrease in mesothelial invasion. Importantly, specific targeting of the mesothelium using siRNA directed at the LPA1 receptor also diminished ovarian cancer cell invasion of the mesothelium. Additionally, we observed that siRNA knockdown of the LPA receptor diminished VCAM-1 expression; re-expression of VCAM-1 to endogenous levels in cells lacking LPA receptor expression restored mesothelial invasion. To determine how LPA regulated VCAM-1 expression, human mesothelial cells derived from ovarian cancer patients (LP9 or LP3) were subjected to siRNA inhibition of LPA1 receptor expression and protein and mRNA expression were evaluated. The results revealed a significant decrease in VCAM-1 protein expression but no impact on VCAM-1 mRNA levels, indicating that LPA does not have a major role in the regulation of VCAM-1 transcription as has been reported in other systems. Rather, it implicates LPA in the regulation of VCAM-1 protein expression. To investigate whether LPA regulates VCAM-1 protein stability, LP9 cells were treated with a eukaryotic translation inhibitor, cycloheximide, for increasing periods of time. VCAM-1 protein half-life decreased after treatment with cycloheximide and LPA1 knockdown compared to control. Taken together, these observations indicate that in addition to targeting the cancer cells, LPA influences the tumor microenvironment to promote mesothelial invasion in part by regulating VCAM-1 protein stability. Citation Format: Timothy A. Raines, Kevin R. Lynch, Jill K. Slack-Davis. LPA-dependent regulation of VCAM-1 in the ovarian cancer metastatic microenvironment and its impact on mesothelial invasion. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2805. doi:10.1158/1538-7445.AM2013-2805

IRF-1 and miRNA126 Modulate VCAM-1 Expression in Response to a High-Fat Meal

A high-fat diet accompanied by hypertriglyceridemia increases an individual's risk for development of atherosclerosis. An early event in this process is monocyte recruitment through binding to vascular cell adhesion molecule 1 (VCAM-1) upregulated on inflamed arterial endothelium. Diets high in polyunsaturated fatty acids (PUFAs) may provide athero-protection by ameliorating this effect. We investigated the acute regulation of VCAM-1 expression in human aortic endothelial cells (HAEC) in response to triglyceride-rich lipoproteins (TGRL) isolated from subjects after consumption of a high-fat meal. Postprandial TGRL isolated from 38 subjects were categorized as proatherogenic or antiatherogenic according to their capacity to alter the inflammatory response of HAEC. Proatherogenic TGRL increased expression of VCAM-1, intercellular adhesion molecule 1 (ICAM-1), and E-selectin by ≈20% compared with stimulation with tumor necrosis factor-α alone, whereas antiatherogenic TGRL decreased VCAM-1 expression by ≈20% while still upregulating ICAM-1. The relative atherogenicity of TGRL positively correlated with particle density of TG, apolipoprotein (Apo)CIII, ApoE, and cholesterol. Ω3-PUFA mimicked the effect of antiatherogenic TGRL by downregulating VCAM-1 expression. TGRL exerted this differential regulation of VCAM-1 by reciprocally modulating expression and activity of the transcription factor interferon regulatory factor 1 (IRF-1) and expression of microRNA 126 (miR-126). Overexpression or silencing of IRF-1 or miR-126 expression recapitulated the proatherogenic or antiatherogenic regulation of VCAM-1. In response to a high-fat meal, TGRL bias the inflammatory response of endothelium via transcriptional and posttranscriptional editing of VCAM-1. Subjects with an anti-inflammatory response to a meal produced TGRL that was enriched in nonesterified fatty acids, decreased IRF-1 expression, increased miR-126 activity, and diminished monocyte arrest.

Canonical Wnt pathway signaling suppresses VCAM-1 expression by marrow stromal and hematopoietic cells

The Wnt family may contribute to hematopoietic stem cell (HSC) maintenance in bone marrow, but many questions remain concerning mechanisms. Vascular cell adhesion molecule-1 (VCAM-1) is expressed in cellular compartments of the bone marrow and might contribute to the HSC niche, but mechanisms concerning its constitutive expression are largely unknown. We now explore the influence of Wnt signaling on cellular adhesion molecule expression by bone marrow stromal and hematopoietic cells. Recombinant Wnt ligands, retroviral Wnt transductions and cocultures with Wnt-secreting cells were used to analyze the effect of Wnt on adhesion molecule expression by stromal and hematopoietic cells. In vivo experiments were also done to assess the ability of Wnt3a-induced, VCAM-1 deficient hematopoietic cells to engraft bone marrow. We now report that the beta-catenin-dependent canonical Wnt signaling pathway negatively regulates VCAM-1 expression on two types of bone marrow cells. Wnt pathway inhibitors, Axin (intracellular) or Dickkopf-1 (extracellular) blocked the regulation of VCAM-1 by diffusible Wnt3a. Interestingly, lipopolysaccharide restored a substantial degree of VCAM-1 expression, suggesting functional cross-talk between Wnt and TLR4 signaling pathways. Decreasing VCAM-1 on HSC-enriched Lin(-) Sca-1(+) c-Kit(Hi) Thy1.1(Lo) cells by exposure to Wnt3a did not prevent their successful transplantation. Our results suggest that cells comprising and residing in the HSC niche can respond to Wnt ligands and extinguish VCAM-1. This response may be important for export of hematopoietic cells. Given the known contribution of VCAM-1 to inflammation, this may represent a new avenue for therapeutic intervention.

Bisacurone inhibits adhesion of inflammatory monocytes or cancer cells to endothelial cells through down-regulation of VCAM-1 expression

Bisacurone, one of the active compounds of the traditionally used indigenous herb Curcuma longa Linne (Zingiberaceae), has anti-oxidant, anti-inflammatory, and anti-metastatic activities. We studied how the level of vascular cell adhesion molecule-1 (VCAM-1), one of the key molecules in the development of atherosclerosis as well as carcinogenesis and metastasis, might be affected by bisacurone in tumor necrosis factor-alpha (TNF-α)-activated human umbilical vein endothelial cells (HUVECs). Bisacurone dose-dependently inhibited TNF-α-mediated expression of VCAM-1. It showed significant suppressive effect on ROS generation in response to TNF-α stimulation and it blocked nuclear factor-kappa B (NF-κB) p65 translocation into the nucleus and phosphorylation of inhibitory factor κBα (IκBα). It also inhibited phosphorylation of Akt and PKC, which are upstream in the regulation of VCAM-1 by TNF-α. Furthermore, bisacurone decreased U937 monocyte and human oral cancer cell (Hep-2, QLL-I, SCC-15) adhesion to HUVECs stimulated by TNF-α, suggesting that it may inhibit the binding of these cells by regulating the expression of critical adhesion molecules by TNF-α. Thus, bisacurone may be beneficial in the treatment of inflammatory diseases, such as atherosclerosis, where inflammatory monocytes are involved in their pathology, and, moreover, in the development of tumors.

Expression of murine VCAM‐1 in vitro and in different models of inflammation in vivo: correlation with immigration of monocytes

VCAM-1 (vascular cell adhesion molecule-1) is a cytokine-inducible adhesion molecule which is known to mediate adhesion of mononuclear cells to endothelial cells in vitro via binding to the integrin VLA-4 (very late antigen-4). To further elucidate the role and regulation of VCAM-1 in vitro, we compared in vitro and in vivo expression of VCAM-1 in response to cytokines and investigated immunohistochemically the expression of VCAM-1 in three murine models of experimental inflammation. These models differed with regard to the pathogenetic mechanism, and the subsesquent infiltrate: allergic contact dermatitis (ACD) to DNFB as a T cell-controlled, DTH type of inflammation, cutaneous infection with Leishmania major as a chronic granulomatous inflammation and the cauterized cornea as a model for acute inflammation. VCAM-1 was found to be markedly enhanced on vascular endothelia in all types of inflammation and after subcutaneous administration of LPS and TNF-alpha. Administration of IL-4, however, failed to induce VCAM-1 both in vivo and in vitro. The increased VCAM-1 expression in the inflammatory models correlated with the appearance of infiltrating monocytes/macrophages. A concomitant influx of CD4-positive/CD8-positive lymphocytes was only observed in ACD and Leishmaniasis.