Long non-coding RNA LINC00675 inhibits tumorigenesis and EMT via repressing Wnt/ß-catenin signaling in esophageal squamous cell carcinoma.

OBJECTIVE: Long noncoding RNA LINC00675 (LINC00675) seems to play an anti-oncogenic role in cancers, though its exact function remains unknown. Up to date, little is known about the role of LINC00675 in esophageal squamous cell carcinoma (ESCC). In this study, we aimed to explore the expression pattern, clinical significance and biological function of LINC00675 in ESCC. PATIENTS AND METHODS: RT-PCR was performed to detect the expression levels of LINC00675 in both ESCC tissue and cell lines. The association of LINC00675 expression with clinicopathological factors and prognosis was statistically analyzed. Cell growth was detected by MTT assay and colony formation assay. Cell apoptosis was evaluated with flow cytometry. Migration and invasion ability of ESCC cells were detected wound healing assay and transwell assays. The expressions of EMT-related proteins and Wnt/ß-catenin-related proteins by Western blot were investigated. RESULTS: LINC00675 expression was significantly downregulated in both ESCC tissues and cell lines. Decreased LINC00675 expression was correlated with histological grade, lymph nodes metastasis and advanced clinical stage. Furthermore, LINC00675 could serve as an independent predictor for overall survival in ESCC. Importantly, in vitro experiments indicated that that forced LINC00675 expression significantly suppressed inhibited ESCC cell proliferation, colony formation, migration, invasion and EMT, and promoted cell apoptosis through suppressing Wnt/ß-catenin signaling pathway. CONCLUSIONS: We suggested that LINC00675 acted as a tumor suppressor in ESCC via regulation of Wnt/ß-catenin signaling pathway and may be a new prognostic biomarker and potential therapeutic target for ESCC intervention.

CTLA4 enhances the osteogenic differentiation of allogeneic human mesenchymal stem cells in a model of immune activation

Allogeneic mesenchymal stem cells (allo-MSCs) have recently garnered increasing interest for their broad clinical therapy applications. Despite this, many studies have shown that allo-MSCs are associated with a high rate of graft rejection unless immunosuppressive therapy is administered to control allo-immune responses. Cytotoxic T-lymphocyte-associated protein 4 (CTLA4) is a co-inhibitory molecule expressed on T cells that mediates the inhibition of T-cell function. Here, we investigated the osteogenic differentiation potency of allo-MSCs in an activated immune system that mimics the in vivo allo-MSC grafting microenvironment and explored the immunomodulatory role of the helper T cell receptor CTLA4 in this process. We found that MSC osteogenic differentiation was inhibited in the presence of the activated immune response and that overexpression of CTLA4 in allo-MSCs suppressed the immune response and promoted osteogenic differentiation. Our results support the application of CTLA4-overexpressing allo-MSCs in bone tissue engineering.

Autologous platelet-rich clot releasate stimulates proliferation and inhibits differentiation of adult rat tendon stem cells towards nontenocyte lineages.

OBJECTIVE: To explore the effects of autologous platelet-rich clot releasate (PRCR) on proliferation and differentiation of adult rat tendon stem cells (TSCs) in vitro, following intense mechanical stretching. METHODS: TSCs were subjected to 8% mechanical stretching and subsequently incubated in control medium or medium supplemented with 2% or 10% PRCR. Collagen types I and III, peroxisome proliferator-activated receptor-γ (PPARγ), sex determining region Y-box 9 (SOX-9) and runt-related transcription factor 2 (RUNX2) concentrations were assessed via Western blotting and flow cytometry. Transforming growth factor (TGF)-ß1 and vascular endothelial growth factor concentrations were measured using enzyme-linked immunosorbent assay. Treated TSCs were also cultured in adipogenic, chondrogenic or osteogenic culture media. RESULTS: PRCR increased the number of TSCs, and the concentrations of collagen types I and III and TGF-ß1. In contrast, PRCR significantly reduced PPARγ, SOX-9 and RUNX2-positive cell numbers, and significantly reduced the numbers of TSC-derived adipocytes, chondrocytes and osteocytes. CONCLUSION: PRCR induced tenocyte differentiation while suppressing the adipocyte, chondrocyte and osteocyte lineages believed to impede tendon healing.

Left atrial diameter, flow-mediated dilation of brachial artery and target organ damage in Chinese patients with hypertension.

To investigate the relationship between left atrial (LA) size, endothelial dysfunction and different markers of target organ damage (TOD), we measured left atrial diameter (LAD) and endothelial function in hypertensive patients with or without TOD. In this study, 197 patients with hypertension were divided into four groups as follows: no TOD (Group I, n=40), one TOD (Group II, n=76), two TOD (Group III, n=46) and ≥3 TOD (Group IV, n=35). Endothelial function was assessed by endothelium-dependent vasodilatation (flow-mediated dilation, FMD) of the brachial artery. We also assessed serum creatinine, the urinary albumin-creatinine ratio (UACR), the intima-media thickness (IMT) of the common carotid, carotid to femoral pulse wave velocity (cf-PWV) and left ventricular mass index (LVMI). Our results were as follows: LA size was increased in 50.8% of patients and was associated with the number of TOD. LAD was larger in the patient groups with ≥3 TOD as compared with patients with two TOD, one TOD and no TOD. FMD was lower in patients with LAD enlargement. LAD exhibited significant relationships with serum creatinine, UACR, cf-PWV, IMT and LVMI. In stepwise multivariate regression analysis, LVMI (ß=0.37, P<0.001), BMI (ß=0.33, P<0.001), duration of hypertension (ß=0.20, P=0.001) and FMD (ß=-0.17, P=0.006) were the independent predictors of LAD. FMD significantly correlated with LAD (ß=-0.26, P=0.001), male sex (ß=-0.23, P=0.004) and pulse pressure (PP) (ß=-0.16, P<0.05). In conclusions, enlargement of LAD may be an important predictor of endothelial dysfunction and may be considered to be an indicator for evaluating TOD in hypertensive patients.

Impaired endothelial function in hypertensive patients with target organ damage.

To evaluate the correlation between endothelial dysfunction and multiple target organ damage (TOD), we measured endothelial function using high-resolution ultrasonography in hypertensive patients with or without TOD. Two hundred and eighty patients with hypertension were divided into four groups as follows: no TOD (Group I, n=61); 1 TOD (Group II, n=113); 2 TOD (Group III, n=59); and >or=3 TOD (Group IV, n=47). Endothelial function was assessed by endothelium-dependent flow-mediated dilatation (FMD) and -independent vasodilation (after sublingual administration of nitroglycerin) of the brachial artery using high-resolution vascular ultrasound. We also assessed the intima-media thickness (IMT) of the common carotid, carotid to femoral pulse wave velocity (cf-PWV) and left ventricular mass index (LVMI). FMD was inversely associated with the number of affected organs. FMD was lower in the patient groups with >or=3 TOD (Group IV: 6.85+/-4.70% vs Group II: 10.00+/-6.15%, P<0.01), 2 TOD (Group III: 7.37+/-5.02% vs Group II, P<0.01) and 1 TOD as compared with patients with no TOD (Group I: 11.88+/-7.11% vs Group II, P<0.05). In univariate correlation analysis, there was a significant relationship between FMD and IMT, serum creatinine, LVMI and cf-PWV. In stepwise multivariate regression analysis, FMD still correlated with waist size (beta=-0.283, P<0.01), age (beta=-0.231, P<0.05) and IMT (beta=-0.197, P=0.05). These findings suggested that reduced FMD was associated with the number of TOD and may be considered an indicator for evaluating TOD.

Quantification of G-Protein Coupled Receptor Internatilization Using G-Protein Coupled Receptor-Green Fluorescent Protein Conjugates with the ArrayScantrade mark High-Content Screening System.

Many G-protein coupled receptors (GPCRs) undergo ligand-dependent homologous desensitization and internalization. Desensitization, defined as a decrease in the responsiveness to ligand, is accompanied by receptor aggregation on the cell surface and internalization via clathrin-coated pits to an intracellular endosomal compartment. In this study, we have taken advantage of the trafficking properties of GPCRs to develop a useful screening method for the identification of receptor mimetics. A series of studies were undertaken to evaluate the expression, functionality, and ligand-dependent trafficking of GPCR-green fluorescent protein (GFP) fusion conjugates stably transfected into HEK 293 cells. These GPCR-GFP expressing cells were then utilized in the validation of the ArrayScantrade mark (Cellomicstrade mark, Pittsburgh, PA), a microtiter plate imaging system that permits cellular and subcellular quantitation of fluorescence in whole cells. These studies demonstrated our ability to measure the internalization of a parathyroid hormone (PTH) receptor-GFP conjugate after ligand treatment by spatially resolving internalized receptors. Internalization was time- and dose-dependent and appeared to be selective for PTH. Similar results were obtained for a beta(2)-adrenergic receptor (beta(2) AR)-GFP conjugate stably expressed in HEK 293 cells. The internalized GFP-labeled receptors were visualized as numerous punctate ³spots² within the cell interior. An algorithm has been developed that identifies and collects information about these spots, allowing quantification of the internalization process. Variables such as the receptor-GFP expression level, plating density, cell number per field, number of fields scanned per well, spot size, and spot intensity were evaluated during the development of this assay. The method represents a valuable tool to screen for receptor mimetics and antagonists of receptor internalization in whole cells rapidly.