BACKGROUND AND OBJECTIVEThe expression of TSLC1 is downregulated or abrogated in many kinds of tumors, and its downregulation is highly associated with DNA hypermethlyation. The aim of this study is to explore the relationship between TSLC1 silencing and DNA methylation of its promoter region in lung cancer cells.

METHODSWe detected the expression pattern of TSLC1 in human normal lung tissue and three lung cancer cell lines (A549, NCI-H446 and Calu-3) by semi-quantitative RT-PCR and Real-time PCR. Then we detected the status of DNA methylation in TSLC1 promoter region with bisulfite sequencing in above normal lung tissue and lung cancer cell lines. After treatment of above cell lines with the inhibitor of DNA methyltransferase 5-Aza-2-deoxycytidine (5-Aza-dC), we detected the expression change of TSLC1 by Real-time PCR before and after the treatment of 5-Aza-dC.

RESULTSThere was no methylation in TSLC1 promoter region in normal lung tissue and A549 cell line in which TSLC1 expressed; while there was DNA hypermethylation in TSLC1 promoter region in NCI-H446 and Calu-3 cell lines in which TSLC1 was abrogated, also the expression of TSLC1 in NCI-H446 and Calu-3 cell lines could be restored after treatment of 5-Aza-dC.

CONCLUSIONThe silencing of TSLC1 in lung cancer cells is due to the hypermethylation of its promoter region.

Azacitidine ; analogs & derivatives ; pharmacology ; Cell Adhesion Molecule-1 ; Cell Adhesion Molecules ; antagonists & inhibitors ; genetics ; Cell Line, Tumor ; DNA Methylation ; Gene Silencing ; Humans ; Immunoglobulins ; genetics ; Lung Neoplasms ; genetics ; pathology ; Promoter Regions, Genetic ; Tumor Suppressor Proteins ; antagonists & inhibitors ; genetics

BACKGROUNDPeriostin originally designated osteoblast-specific factor 2 (OSF-2) is frequently found to be highly expressed in various types of human cancer cell lines in vitro and human cancer tissues in vivo. We proposed that periostin was a key factor during the process of proliferation and invasion in cancer cells. We investigated the effect of periostin on the function of human osteosarcoma cell line (U2OS), such as proliferation, apoptosis, invasion and the associated signal pathway.

METHODSA human PGCsi/U6 promoter-driven DNA template was adopted to induce short hairpin RNA (shRNA)-triggered RNA interference (RNAi) to block periostin gene expression in the cell line U2OS. U2OS cells were divided into three groups: cells transfected with phosphate buffered saline as control group (the U2OS group), cells transfected with pGCsi as negative control group (the NC group) and cells transfected with periostin/pGCsi as experimental group (the pGCsi-periostin group). Then, transfection efficiency of cell was observed under fluorescent microscope. The expressions of periostin and the related genes in cells were detected by reverse transcription polymerase chain reaction and Western Blotting. Cell viability was determined using the methyl-thiazolyl tetrazolium bromide (MTT) quantitative colorimetric assay. The invasion and migration capability of cells were tested by transwell plates with or without extracellular matrix gel. Furthermore, the changes of cell cycle and apoptosis were analyzed by flow cytometry.

RESULTSThe transfection efficiency of periostin/pGCsi to U2OS cells was about 70% - 80%. When compared with the NC group, the levels of mRNA and protein of periostin in the pGCsi-periostin group decreased by 82% (F = 564.71, P < 0.001) and 58% (F = 341.51, P < 0.001), respectively. Meantime, the earlier apoptosis value increased by 417% (F = 28.69, P < 0.001). The percentage of S phase pGCsi-periostin cells decreased by 21% (F = 47.00, P < 0.001), however, that of G0 - G1 phase cells increased by 12% (F = 14.50, P < 0.001). The capability of migration and invasion reduced by 41% (F = 17.79, P < 0.001) and 72% (F = 197.08, P < 0.001), respectively. The cell proliferation in the pGCsi-periostin group decreased by 59% and 72% at 48 and 120 hours after transfection, respectively. The mRNA expressions of transforming growth factor-β and vascular endothelial growth factor decreased by 17% (F = 73.99, P < 0.001) and 47% (F = 30.25, P < 0.001), respectively. A tendency of lower focal adhesion kinase (FAK) was shown in pGCsi-periostin cells but without any statistically significant difference. Otherwise the expression of p-FAK in those cells had markedly decreased by 21% (F = 16.81, P < 0.001).

CONCLUSIONSRNAi against periostin can effectively down-regulate periostin gene expression. Periostin increases the hyperplasia and invasion of cancer cells. Periostin might be involved in and served as a tumor promoter gene in the pathogenesis of osteosarcoma.

Apoptosis ; Bone Neoplasms ; etiology ; pathology ; Cell Adhesion Molecules ; antagonists & inhibitors ; genetics ; physiology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Focal Adhesion Protein-Tyrosine Kinases ; metabolism ; Humans ; Integrin alphaVbeta3 ; physiology ; Neoplasm Invasiveness ; Osteosarcoma ; etiology ; pathology ; Phosphorylation ; RNA Interference ; Transfection

The interactions between blood cells and blood cells or blood cells and endothelium of blood vessel are mainly mediated by adhesion molecules. The role of adhesion molecules is diverse in vivo, which involved in adhesion, migration, differentiation and signal transduction of blood cells. The function of adhesion molecules is necessary to maintain the normal structure and fulfill many physiological processes of these cells. Therefore, the abnormal or deficiency of their expression and function will disrupts normal physiological processes and results in clinical disease. In this paper, several generic classes of adhesion molecules, including the integrins, the selectins, the immunoglobulin superfamily and others are introduced, and a lot of related physiopathological status, such as inflammation, hemostasis, arteriosclerosis, thrombosis and stem cell homing are discussed. The studies on the adhesion molecules of blood cells will contribute not only to understand the pathogenesis of some disorders, but also to search new targets in diagnosis and treatment of these diseases.
Animals ; Antibodies, Monoclonal ; therapeutic use ; Arteriosclerosis ; etiology ; Blood Cells ; chemistry ; Cell Adhesion Molecules ; antagonists & inhibitors ; physiology ; Humans ; Inflammation ; etiology ; Integrins ; physiology ; Selectins ; physiology ; Thrombosis ; etiology

OBJECTIVETo investigate the inhibitory effect of naringin on monocyte adhesion to high glucose-induced human umbilical vein endothelial cells (HUVECs).

METHODSCultured HUVECs isolated from human umbilical cords were pretreated with or without naringin and induced with high glucose (33 mmol/L) for 48 h. Human monocyte THP-1 cells, after labeling with BCECF-AM, were co-cultured with the HUVECs for 30 min. The labeled THP-1 cells adhering to HUVECs were observed under fluoroscence microscope, and the inhibitory effect of naringin on the cell adhesion was evaluated by measuring the adhering cell density. Western blot analysis was used to detect the expressions of the adhesion molecules in the HUVECs, and reactive oxygen species (ROS) production in the HUVECs was measured using an oxidation-sensitive fluorescent probe (DCFH-DA). The nuclear extracts of the HUVECs were prepared to examine the expression of nuclear factor-kappa B (NF-kappaB) in the cell nuclei by Western blotting.

RESULTSHUVECs in high-glucose culture showed increased adhesion to THP-1 cells and enhanced expressions of the cell adhesion molecules, which were significantly attenuated by pretreatment with naringin (10-50 microg/ml). High glucose induced DCF-sensitive intracellular ROS production in the HUVECs, and this effect was inhibited by naringin pretreatment of the cells. Naringin also suppressed high glucose-induced increment of NF-kappaB expression in the cell nuclei of HUVECs.

CONCLUSIONNaringin can suppress high glucose-induced vascular inflammation possibly by inhibiting ROS production and NF-kappaB activation in HUVECs.

Cell Adhesion ; drug effects ; Cell Adhesion Molecules ; metabolism ; Cell Line ; Cells, Cultured ; Coculture Techniques ; Endothelial Cells ; cytology ; Flavanones ; pharmacology ; Glucose ; antagonists & inhibitors ; pharmacology ; Humans ; Monocytes ; cytology ; NF-kappa B ; metabolism ; Reactive Oxygen Species ; metabolism ; Umbilical Veins ; cytology

AIMTo develop a high throughput screening assay to identify inhibitors of intercellular adhesion molecule-1 (ICAM-1) expression in human umbilical vein endothelial cells (HUVEC).

METHODSICAM-1 expression in lipopolysaccharide-stimulated endothelial cells was measured by ELISA. The cytotoxicity of the compounds was measured by MTT.

RESULTSLipopolysaccharide (LPS) increased ICAM-1 expression in HUVEC in a concentration- and time-dependent manner. Two thousand compounds were screened and the hit rate was 1.5%. Among these 30 compounds, 24 were cytotoxic.

CONCLUSIONThe ELISA method was inexpensive, reproducible and suitable for high throughput primary cell assay. This assay was feasible to identify inhibitors of ICAM-1 and simultaneously discriminate the activity from the cytotoxic effects.

Cell Adhesion Molecules ; antagonists & inhibitors ; biosynthesis ; Cells, Cultured ; Chemistry, Pharmaceutical ; methods ; Drug Evaluation, Preclinical ; methods ; Endothelium, Vascular ; cytology ; metabolism ; Humans ; Intercellular Adhesion Molecule-1 ; drug effects ; metabolism ; Lipopolysaccharides ; pharmacology ; Umbilical Veins ; cytology ; metabolism

Conventional medical treatment for ulcerative colitis can have limited efficacy or severe adverse reactions requiring additional treatment or colectomy. Hence, different biological agents that target specific immunological pathways are being investigated for treating ulcerative colitis. Anti-tumor necrosis factor (TNF) agents were the first biologics to be used for treating inflammatory bowel disease. For example, infliximab and adalimumab, which are anti-TNF agents, are being used for treating ulcerative colitis. Recently, golimumab, another anti-TNF agent, and vedolizumab, an anti-adhesion therapy, have been approved for ulcerative colitis by the U.S. Food and Drug Administration. In addition, new medications such as tofacitinib, a Janus kinase inhibitor, and etrolizumab, another anti-adhesion therapy, are emerging as therapeutic agents. Therefore, there is a need for further studies to select appropriate patient groups for these biologics and to improve the outcomes of ulcerative colitis treatment through appropriate medical usage.
Antibodies, Monoclonal/therapeutic use ; Antibodies, Monoclonal, Humanized/therapeutic use ; Biological Factors/*therapeutic use ; Cell Adhesion Molecules/antagonists & inhibitors ; Colitis, Ulcerative/*drug therapy ; Humans ; Janus Kinases/antagonists & inhibitors ; Piperidines/therapeutic use ; Pyrimidines/therapeutic use ; Pyrroles/therapeutic use

Earlier report showed that expression of a splice variant of CD99 transmembrane protein increases invasive ability of human breast cancer cells. Cell motility was also significantly enhanced by the CD99 splice variant expression. In an effort to identify the cellular components that mediate a signal transduction pathway triggered by the CD99 splice variant, known signal path inhibitors were examined for their effects on the motility of the CD99 splice variant-transfected MDA-MB-231 breast cancer cells. Phenylarsine oxide, an inhibitor of phosphatase specific for focal adhesion kinase, and PP1, an inhibitor of src kinase family, significantly suppressed motility of the cells. Among different types of src transfectant clones generated, kinase-negative mutant src transfectant cells were 80% less motile than the mock cells transfected with an empty-vector, while v-src and c-src transfectants exhibited cell motility levels at or slightly above the mock transfectant. These results suggest that src and focal adhesion kinase mediate the intracellular signaling pathway of a CD99 splice variant for the induction of motility of human breast cancer cells.
Antigens, CD/*genetics ; Arsenicals/pharmacology ; Breast Neoplasms/*enzymology/genetics/*pathology ; Cell Adhesion Molecules/*genetics ; Cell Movement/drug effects ; Gene Expression ; Protein-Tyrosine Kinase/antagonists & inhibitors/*metabolism ; Pyrazoles/pharmacology ; Pyrimidines/pharmacology ; Signal Transduction/drug effects ; Transfection ; Tumor Cells, Cultured ; src-Family Kinases/antagonists & inhibitors/*metabolism

CD137, which is expressed on activated T cells, plays a critical role in inflammatory responses. However, the exact role that CD137 plays in monocytes is not fully known. Here we studied the expression and function of CD137 in human monocytic THP-1 cells, which we found constitutively expresses CD137 at the mRNA and protein level. Cross-linking of CD137 increased the secretion of IL-8 and TNF-alpha, promoted the expression of CD54 and CD11b, and increased adhesion to extracellular matrix (ECM) proteins. In particular CD137-induced adhesion of THP-1 cells was inhibited by an inhibitor of mitogen-activated protein kinase kinase (MEK), but not by a p38 kinase inhibitor. Taken together, these results show that the adhesion and cytokine production of THP-1 cells induced by CD137 occur via activation of MEK, which results in the activation of ERK-1/2 signaling pathways. Therefore, this study suggests that CD137 induces an activating and migrating signal during inflammatory processes.
Antigens, CD/biosynthesis/*immunology ; Antigens, CD11/biosynthesis ; *Cell Adhesion ; Cell Adhesion Molecules/biosynthesis ; Cell Line ; Cytokines/*biosynthesis ; Enzyme Activation ; Extracellular Matrix Proteins/metabolism ; Flow Cytometry ; Humans ; Immunity, Natural ; Intercellular Adhesion Molecule-1/biosynthesis ; Interleukin-8/biosynthesis ; Mitogen-Activated Protein Kinase 1/metabolism ; Mitogen-Activated Protein Kinase 3/metabolism ; Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors/metabolism ; Monocytes/metabolism/*physiology ; Phosphorylation ; Protein Binding ; Receptors, Nerve Growth Factor/biosynthesis/*immunology ; Receptors, Tumor Necrosis Factor/biosynthesis/*immunology ; Research Support, Non-U.S. Gov't ; Signal Transduction ; Tumor Necrosis Factor-alpha/biosynthesis ; p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors

Down syndrome cell adhesion molecule (DSCAM) acts as a netrin-1 receptor and mediates attractive response of axons to netrin-1 in neural development. However, the signaling mechanisms of netrin-DSCAM remain unclear. Here we report that AMP-activated protein kinase (AMPK) interacts with DSCAM through its γ subunit, but does not interact with DCC (deleted in colorectal cancer), another major receptor for netrin-1. Netrin-treatment of cultured cortical neurons leads to increased phosphorylation of AMPK. Both AMPK mutant with dominant-negative effect and AMPK inhibitor can significantly suppress netrin-1 induced neurite outgrowth. Together, these findings demonstrate that AMPK interacts with DSCAM and plays an important role in netrin-1 induced neurite outgrowth. Our study uncovers a previously unknown component, AMPK, in netrin-DSCAM signaling pathway.
AMP-Activated Protein Kinases ; antagonists & inhibitors ; genetics ; metabolism ; Animals ; Cell Adhesion Molecules ; genetics ; metabolism ; Cells, Cultured ; HEK293 Cells ; Humans ; Mice ; Nerve Growth Factors ; pharmacology ; Netrin-1 ; Neurites ; physiology ; Neurons ; cytology ; drug effects ; metabolism ; Phosphorylation ; Protein Binding ; Protein Kinase Inhibitors ; pharmacology ; RNA Interference ; RNA, Small Interfering ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Signal Transduction ; drug effects ; Transfection ; Tumor Suppressor Proteins ; pharmacology