Corrigendum to ‘Pediatric sarcomas display a variable EpCAM expression in a histology-dependent manner’ [Translational Oncology 13 (2020) 100846]

Abstract Abstract 4583 Stromal derived factor-1 (SDF-1) binds to seven transmembrane-span G-protein coupled receptor CXCR4 and directs homing of CXCR4+ hematopoietic stem cells to bone marrow (BM) as well as metastasis of CXCR4+ cancer cells. Recently, a new SDF-1 binding receptor has been identified and named CXCR7. With identification of this receptor a role of SDF-1 in directing chemotaxis of CXCR7+ hematopoietic cells as well as metastasis of CXCR7+ tumors become more complex. While CXCR7 is expressed at very low level on normal hematopoietic stem cells, its expression becomes high on leukemic cells. Similarly we noticed high expression of CXCR7 on several pediatric sarcomas (e.g., rhabdomyosarcomas and neuroblastomas) that very often metastasize/infiltrate BM. The aim of our study was to evaluate 5′ fragment of CXCR7 gene for promoter activity and analyze how its expression is regulated in CXCR7+ human hematopoietic cells as well as in CXCR7+ human rhabdomyosarcoma cells (RMS). The putative CXCR7 promoter was cloned by employing specific primers for 5′ fragment of CXCR7 gene. We found that this 2.5 kb 5′ DNA fragment adjacent to CXCR7 gene contains three potential hypoxia responsive element (HRE)- (-100-104, -965-969, -1306-1310), five NF-kB- (-32-42, -308-318, -1019-1029, -1375-1379, -2145-2155), four NRF-1 binding sites (-1030-1040, -1468-1478, -1980-1990, -2085-2095), one c-myb binding site at -15-19 and at -702-706 a binding site for negative transcription regulatory factor YY1. We generated 8 constructs containing smaller CXCR7 promoter fragments and three constructs containing mutated distal NF-kB and HREs as well as c-myb that were subcloned into a pGL4.10 vector. The promoter activity of these fragments was tested in transfected human hematopoietic cells (THP-1) and RMS cell line (RD) by measuring luciferase activity. While the minimal promoter activity in human hematopoietic cells was retained in 80 bp short fragment containing c-myb binding site, similar activity in human rhabdomyosarcoma cells required longer 150 bp fragment containing proximal NF-kB binding element. We noticed that while mutation of c-myb binding site in CXCR7 promoter in THP-1 cells reduces promoter activity by ∼50%, mutation of proximal NF-kB-binding site in CXCR7 promoter completely inhibits promoter activity in RD cells. This was confirmed by knock-down of c-myb by shRNA and chemical inhibition of NF-kB respectively. Furthermore, we noticed that during hypoxia in contrast to CXCR4, CXCR7 expression does not change in hematopoietic cells, however is significantly downregulated in rhabdomyosarcoma cells. This could be explained by upregulation of negative transcripton factor YY1 during hypoxia, as evidenced by RQ-PCR and confirmed by CHIP assay. In conclusion we have demonstrated that 5′ fragment of CXCR7 possesses promoter activity and is differently regulated in hematopoietic versus sarcoma cells - in c-myb or NF-kB dependent manner respectively. Furthermore, we also found that in contrast to hematopoietic cells hypoxia inhibits CXCR7 promoter activity in RMS cells in YY1-dependent manner. Disclosures: No relevant conflicts of interest to declare.

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Immunogold labeling of the calcium binding protein synexin in isolated adrenal chromaffin granules and chromaffin cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162326 ◽

1990 ◽

Vol 48 (3) ◽

pp. 952-953

Author(s):

Gemma A.J. Kuijpers ◽

Harvey B. Pollard

Keyword(s):

Adrenal Medulla ◽

Calcium Binding ◽

Chromaffin Cells ◽

Cell Activation ◽

Structural Information ◽

Dependent Manner ◽

Chromaffin Granules ◽

Immuno Electron Microscopy ◽

Ultrathin Sections ◽

Adrenal Chromaffin

Exocytotic fusion of granules in the adrenal medulla chromaffin cell is triggered by a rise in the concentration of cytosolic Ca2+ upon cell activation. The protein synexin, annexin VII, was originally found in the adrenal medulla and has been shown to cause aggregation and to support fusion of chromaffin granules in a Ca2+-dependent manner. We have previously suggested that synexin may there fore play a role in the exocytotic fusion process. In order to obtain more structural information on synexin, we performed immuno-electron microscopy on frozen ultrathin sections of both isolated chromaffin granules and chromaffin cells.Chromaffin granules were isolated from bovine adrenal medulla, and synexin was isolated from bovine lung. Granules were incubated in the presence or absence of synexin (24 μg per mg granule protein) and Ca2+ (1 mM), which induces maximal granule aggregation, in 0.3M sucrose-40m MMES buffer(pH 6.0). Granules were pelleted, washed twice in buffer without synexin and fixed with 2% glutaraldehyde- 2% para formaldehyde in 0.1 M phosphate buffer (GA/PFA) for 30 min. Chromaffin cells were isolated and cultured for 3-5 days, and washed and incubated in Krebs solution with or without 20 uM nicotine. Cells were fixed 90 sec after on set of stimulation with GA/PFA for 30 min. Fixed granule or cell pellets were washed, infiltrated with 2.3 M sucrose in PBS, mounted and frozen in liquid N2.

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Spindle scaling mechanisms

Essays in Biochemistry ◽

10.1042/ebc20190064 ◽

2020 ◽

Vol 64 (2) ◽

pp. 383-396

Author(s):

Lara K. Krüger ◽

Phong T. Tran

Keyword(s):

Cell Size ◽

Spindle Assembly ◽

Dependent Manner ◽

Post Translational Modification ◽

Size Dependent ◽

A Cell ◽

Chromosome Separation ◽

Spindle Elongation ◽

Protein Gradients ◽

Spindle Structure

Abstract The mitotic spindle robustly scales with cell size in a plethora of different organisms. During development and throughout evolution, the spindle adjusts to cell size in metazoans and yeast in order to ensure faithful chromosome separation. Spindle adjustment to cell size occurs by the scaling of spindle length, spindle shape and the velocity of spindle assembly and elongation. Different mechanisms, depending on spindle structure and organism, account for these scaling relationships. The limited availability of critical spindle components, protein gradients, sequestration of spindle components, or post-translational modification and differential expression levels have been implicated in the regulation of spindle length and the spindle assembly/elongation velocity in a cell size-dependent manner. In this review, we will discuss the phenomenon and mechanisms of spindle length, spindle shape and spindle elongation velocity scaling with cell size.

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A colon epithelial protein(s) induces oral tolerance in a dose dependent manner in the trinitrobenzene sulfonic acid (TNBS) model of colitis in rats

Gastroenterology ◽

10.1016/s0016-5085(01)81385-8 ◽

2001 ◽

Vol 120 (5) ◽

pp. A279-A279

Author(s):

A DASGUPTA ◽

J GIRALDO ◽

P AMENTA ◽

K DAS

Keyword(s):

Sulfonic Acid ◽

Oral Tolerance ◽

Protein S ◽

Trinitrobenzene Sulfonic Acid ◽

Dependent Manner ◽

Dose Dependent

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The Anti-Atherogenic Properties of Sesamin are Mediated via Improved Macrophage Cholesterol Efflux Through PPARγ1-LXRα and MAPK Signaling

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000195 ◽

2014 ◽

Vol 84 (1-2) ◽

pp. 79-91 ◽

Cited By ~ 7

Author(s):

Amin F. Majdalawieh ◽

Hyo-Sung Ro

Keyword(s):

Cholesterol Efflux ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Foam Cell ◽

Mapk Signaling ◽

Luciferase Reporter ◽

Foam Cell Formation ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Macrophage Cholesterol Efflux

Background: Foam cell formation resulting from disrupted macrophage cholesterol efflux, which is triggered by PPARγ1 and LXRα, is a hallmark of atherosclerosis. Sesamin and sesame oil exert anti-atherogenic effects in vivo. However, the exact molecular mechanisms underlying such effects are not fully understood. Aim: This study examines the potential effects of sesamin (0, 25, 50, 75, 100 μM) on PPARγ1 and LXRα expression and transcriptional activity as well as macrophage cholesterol efflux. Methods: PPARγ1 and LXRα expression and transcriptional activity are assessed by luciferase reporter assays. Macrophage cholesterol efflux is evaluated by ApoAI-specific cholesterol efflux assays. Results: The 50 μM, 75 μM, and 100 μM concentrations of sesamin up-regulated the expression of PPARγ1 (p< 0.001, p < 0.001, p < 0.001, respectively) and LXRα (p = 0.002, p < 0.001, p < 0.001, respectively) in a concentration-dependent manner. Moreover, 75 μM and 100 μM concentrations of sesamin led to 5.2-fold (p < 0.001) and 6.0-fold (p<0.001) increases in PPAR transcriptional activity and 3.9-fold (p< 0.001) and 4.2-fold (p < 0.001) increases in LXR transcriptional activity, respectively, in a concentration- and time-dependent manner via MAPK signaling. Consistently, 50 μM, 75 μM, and 100 μM concentrations of sesamin improved macrophage cholesterol efflux by 2.7-fold (p < 0.001), 4.2-fold (p < 0.001), and 4.2-fold (p < 0.001), respectively, via MAPK signaling. Conclusion: Our findings shed light on the molecular mechanism(s) underlying sesamins anti-atherogenic effects, which seem to be due, at least in part, to its ability to up-regulate PPARγ1 and LXRα expression and transcriptional activity, improving macrophage cholesterol efflux. We anticipate that sesamin may be used as a therapeutic agent for treating atherosclerosis.

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Vitamin D Supplementation and Serum Levels of Magne-sium and Selenium in Type 2 Diabetes Mellitus Patients: Gender Dimorphic Changes

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000190 ◽

2014 ◽

Vol 84 (1-2) ◽

pp. 27-34 ◽

Cited By ~ 7

Author(s):

Nasser M. Al-Daghri ◽

Khalid M. Alkharfy ◽

Nasiruddin Khan ◽

Hanan A. Alfawaz ◽

Abdulrahman S. Al-Ajlan ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Vitamin D ◽

Type 2 Diabetes Mellitus ◽

Serum Levels ◽

Vitamin D Supplementation ◽

Serum Selenium ◽

Dependent Manner

The aim of our study was to evaluate the effects of vitamin D supplementation on circulating levels of magnesium and selenium in patients with type 2 diabetes mellitus (T2DM). A total of 126 adult Saudi patients (55 men and 71 women, mean age 53.6 ± 10.7 years) with controlled T2DM were randomly recruited for the study. All subjects were given vitamin D3 tablets (2000 IU/day) for six months. Follow-up mean concentrations of serum 25-hydroxyvitamin D [25-(OH) vitamin D] significantly increased in both men (34.1 ± 12.4 to 57.8 ± 17.0 nmol/L) and women (35.7 ± 13.5 to 60.1 ± 18.5 nmol/L, p < 0.001), while levels of parathyroid hormone (PTH) decreased significantly in both men (1.6 ± 0.17 to 0.96 ± 0.10 pmol/L, p = 0.003) and women (1.6 ± 0.17 to 1.0 ± 0.14 pmol/L, p = 0.02). In addition, there was a significant increase in serum levels of selenium and magnesium in men and women (p-values < 0.001 and 0.04, respectively) after follow-up. In women, a significant correlation was observed between delta change (variables at six months-variable at baseline) of serum magnesium versus high-density lipoprotein (HDL)-cholesterol (r = 0.36, p = 0.006) and fasting glucose (r = - 0.33, p = 0.01). In men, there was a significant correlation between serum selenium and triglycerides (r = 0.32, p = 0.04). Vitamin D supplementation improves serum concentrations of magnesium and selenium in a gender-dependent manner, which in turn could affect several cardiometabolic parameters such as glucose and lipids.

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Duffy antigen / receptor for chemokines correlates with inflammatory reaction in rats with venous hypertension: implication for the pathogenesis of primary chronic venous disease

VASA ◽

10.1024/0301-1526/a000327 ◽

2014 ◽

Vol 43 (1) ◽

pp. 47-54 ◽

Cited By ~ 1

Author(s):

Weibin Huang ◽

Weiwei Qin ◽

Lei Lv ◽

Haoyv Deng ◽

Hao Zhang ◽

...

Keyword(s):

Mononuclear Cells ◽

Early Stage ◽

Antigen Receptor ◽

Venous Hypertension ◽

Skin Tissue ◽

Chronic Venous Disease ◽

Venous Disease ◽

Dependent Manner ◽

Time Points ◽

Duffy Antigen

Background: Duffy antigen / receptor for chemokines (DARC) possesses high affinity for several chemokine subgroups of CC and CXC. Although DARC has been shown to play a role in many inflammatory diseases, its effect on chronic venous disease (CVD) remains unidentified. We explored whether the expression of DARC in skin tissue was activated under venous hypertension as well as the relationships between DARC and inflammation. Materials and methods: The inflammation in a rat model of venous hypertension caused by a femoral arterial-venous fistula (AVF) was studied. At specified intervals the pressure in the femoral veins was recorded within 42 days. Hindlimb skin specimens were harvested at different time points. The expressions of DARC, interleukin-8 (IL-8), and monocyte chemotactic protein-1 (MCP-1) in skin tissue were examined. Mononuclear cells infiltrated in skin tissue were detected. Results: Femoral venous pressures in AVF groups increased significantly at different time points (P < 0.01). DARC was expressed in skin tissue and its expression level increased significantly in AVF groups from the 7nd day on and was enhanced in a time-dependent manner within 42 days (P < 0.05). Meanwhile, both MCP-1 and IL-8 had higher levels, accompanied by increased mononuclear cells infiltrating into skin tissue (P < 0.05). Conclusions: A rat AVF model which can maintain venous hypertension for at least 42 days is competent for researching the pathogenesis of CVD. DARC, which plays a role in the inflammation of skin tissue under venous hypertension, may become a new molecular target for diagnosis and treatment of CVD at a very early stage.

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