Reconstruction and analysis of circRNA-miRNA-mRNA network in the pathology of lung cancer

BACKGROUND

The presented study aimed to gain insights into the pathogenesis of lung cancer (LC) and provide novel bio-markers for LC by building a regulatory circular (circ) RNAmicro (mi) RNAmRNA network.

MATERIALS AND METHODS

High-throughput sequencing data of circRNAs, miRNAs and mRNAs related to LC originated from GEO (Gene Expression Omnibus) database, and the differential expressions of circRNAs, miRNAs and mRNAs were screened with R language Limma. The circRNA-miRNA and miRNA-mRNA pairs were used to build the ceRNA network. The functions of differential expression circRNAs were elucidated by performing the functional enrichment analysis on GO and KEGG. Furthermore, the selected LC prognostic genes were verified by tissue chips and immunohistochemistry (IHC).

RESULTS

On the whole, 20 downregulated circRNAs, 55 upregulated miRNAs and 243 downregulated mRNAs were identified in LC. Lastly, a circRNA-miRNA-mRNA ceRNA network was built, which was composed of 2 circRNAs, 2 miRNAs, and 2 mRNAs. As indicated from the analysis based on public databases and IHC, the differential genes (i.e., FXYD1 and SEMA5A) in this network acted as LC prognostic factors. As confirmed by performing IHC and survival analyses, FXYD1 and SEMA5A expressions in LC were downregulated, and their expressions displayed a relationship to the overall survival (OS) of LC cases.

CONCLUSIONS

This study presents novel insights into the role of circRNAs in the development of LC via the ceRNA mechanism. The identified FXYD1 and SEMA5A gene could act as novel and vital LC prognostic indicators.

P–285 Controlling semi-invasive activity of human endometriotic stromal cells by inhibiting NF-kB signaling pathway using aloe-emodin or aspirin

Study question

Does inhibiting nuclear factor-kB (NF-kB) signaling by aloe-emodin (AE) or aspirin (Asp), as anti-inflammatory compounds, suppress the invasive activity of stage IV human endometriotic stromal cells?

Summary answer

Eutopic endometriotic stromal cells (EuESCs) seem to have a semi-invasive activity which is largely suppressed by AE or Asp.

What is known already

Inflammation and its master regulator, NF-kB, have been implicated in the development of endometriosis. Inhibition of NF-kB pathway using small molecules ameliorated disease progression and reduced the lesion size; nevertheless, underlying mechanism is not fully understood.

Study design, size, duration

In this cross-sectional study, a total of 8 infertile patients with proven endometriosis and 8 women without endometriosis (Control group) undergoing infertility treatment cycles, were enrolled between October 2018 and December 2019. The invasiveness of collected endometriotic stromal cells before and after treatment with AE or Asp, was analyzed and compared with the control group.

Participants/materials, setting, methods

The eutopic endometriotic and healthy endometrial biopsies were digested and the single cells were cultured. Gene and protein expression of proliferation, adhesion, and invasion markers of eutopic endometriotic stromal cells (EuESCs) with and without treatment with AE or Asp, as well as control endometrial stromal cells (CESCs) were analyzed using q-PCR and immunofluorescence staining, respectively. Cell migration capacity was assessed by wound closure assay.

Main results and the role of chance

We observed an association between NF-kB overexpression and higher proliferation/adhesion capacity in EuESCs. TNF-α, as a known NF-kB inducer, further potentiated this association. EuESCs at stage IV, displayed silent invasive and migratory behaviors. Pretreatment of EuESCs with AE or Asp significantly attenuated NF-kB expression and reduced proliferative, adhesive, invasive and migratory activity.

Limitations, reasons for caution

Due to some adverse effects observed following treatment with AE or Asp on the normal activity of EuESCs, more investigations on possible toxicity of the treatment, must be considered.

Wider implications of the findings: We suggest that both Asp and AE (as potent NF-kB inhibitors) may be useful as a supplement to conventional endometriosis treatments.

Trial registration number

Not applicable

Compassionate behaviours of clinical nurses in Iran: an ethnographic study

AIM

The aim of this research was to explore compassionate behaviour in Iranian nurses.

BACKGROUND

Nurses provide high-quality care with compassion. It is useful to improve relationships between nurses and patients to give them more confidence in the care process. It is important to consider how compassion is demonstrated by nurses and to explore different compassionate behaviours in different cultures.

METHODS

This ethnographic study was conducted with 20 nurses and 12 patients in six medical and four surgical wards in Iran in 2014-2015. Data were collected through fieldwork observations and semi-structured deep interviews and field notes. We analysed data using constant comparison based on Strauss and Corbin method.

RESULTS

Results of the present study showed four cultural themes; love expression and compassion in the form of non-verbal emotional behaviours, empathy with others, emotional supports of patients at bedside and non-caring behaviours.

CONCLUSION

The findings of this study described compassionate behaviours in nurses. Compassionate behaviours of nurses are closely related to the culture issues. These are formed by communication between nurses and patients, and nurses and patients' families during nursing care. Thus improving compassionate behaviours is highly significant in nursing.

IMPLICATIONS FOR NURSING AND/HEALTH POLICY

Nurses, instructors and policy-makers can use the results of this study. They should consider compassionate care as an important component of patient-centred care. Compassion should be considered in nursing and practical educational programmes. To develop the compassionate care, it is vital to make changes in the dominant philosophy and culture of caring environments. Nurses should receive appropriate training with focus on holistic and patient-centred approaches.

Physalis alkekengi and Alhagi maurorum ameliorate the side effect of cisplatin-induced nephrotoxicity

Cisplatin is frequently being used for the treatment of different tumors, although the application of this agent is associated with nephrotoxicity. Here, we explored the antioxidant and anti-inflammatory activities of Physalis alkekengi and Alhagi maurorum; 400 mg kg(-1) per day P. alkekengi and 100 mg kg(-1) per day A. maurorum were administered in rats, orally for 10 days after a single dose of 7 mg kg(-1) intraperitoneal cisplatin. The concentrations of creatinine, urea-nitrogen, and relative and absolute excretion of sodium/potassium were evaluated before/after therapy. Levels of malondialdehyde (MDA) and ferric-reducing antioxidant power (FRAP) were measured to assess the oxidative stress induced by cisplatin. Moreover, tissues sections were used for histological analyses and evaluation of the degree of tissue damage. Cisplatin increased serum levels of creatinine and urea-nitrogen, relative/absolute excretion of sodium/potassium, and MDA, whereas decreased FRAP level. Interestingly, P. alkekengi or A. maurorum were able to reduce the level of the renal function markers as well as the levels of sodium/potassium. This effect was more pronounced by P. alkekengi. Moreover, cisplatin induced pathological damage in kidney, whereas treatment with these agents improved this condition. Our findings demonstrate the potential therapeutic impact of P. alkekengi and A. maurorum for improving cisplatin-induced nephrotoxicity, supporting further investigations on the novel potential clinical application of these agents for patients being treated with cisplatin to ameliorate cisplatin-induced nephrotoxicity.

Enhanced skin penetration of lidocaine through encapsulation into nanoethosomes and nanostructured lipid carriers: a comparative study

Lipid based nanoparticles have become a major research object in topical drug delivery to enable drugs to pass the stratum corneum and reach the desired skin layer. The present investigation deals with the encapsulation of lidoacine into nanostructured lipid carriers (NLCs) and nanoethosomes for improving its dermal delivery and consequently local anesthetic efficacy. Concurrently these two topical delivery systems were compared. Lidocaine-loaded NLCs and nanoethosomes were characterized by various techniques and used for an in vitro skin penetration study using excised rat skin and Franz diffusion cells. The nanoparticles were tracked in the skin by following the Rhodamine-labled nanocarriers under fluorescent microscopy. Optimized lidocaine-loaded NLCs (size 96 nm, zeta potential -13.7 mV, encapsulation efficiency (EE) % 69.86% and loading capacity (LC) % 10.47%) and nanoethosomes (size 105.4 nm, zeta potential -33.6 mV, EE 40.14% and LC 8.02%) were chosen for a skin drug delivery study. Higher skin drug deposition of NLCs and nanoethosomal formulations compared to lidocaine hydroalcoholic solution represented a better localization of the drug in the skin. NLC formulation showed the lowest entered drug in the receptor phase of Franz diffusion cell in comparison with nanoethosomes and hydroalcoholic solution confirming the highest skin accumulation of drug. Both colloidal systems showed superiority over the drug solution for dermal delivery of lidocaine, however, NLC exhibited more promising characteristics than nanoethosomes regarding drug loading and skin targeted delivery.

Administration of exogenous endothelin-1 following vascular balloon injury: early and late effects on intimal hyperplasia

Administration of exogenous endothelin-1 (ET-1) has been shown to stimulate neointimal hyperplasia following arterial balloon angioplasty (BA). However, the specific effects of ET-1 on the cellular and extracellular matrix response of the vessel wall after balloon injury and the persistence of these ET-1 effects have not been studied. The objectives of this study were to determine the acute (1 week) and long term (10 weeks) effects of administering exogenous ET-1 after arterial BA on neointimal hyperplasia, collagen synthesis and content, cellular proliferation, and ET(A) and ET(B) receptor expression. Thirty-one rabbits were randomized to receive subcutaneous ET-1 (500 pmol/kg/day for 1 week) or placebo time-release pellets and sacrificed at either 1 or 10 weeks after BA. At 1 week, there was a significant two-fold increase in intimal cross-sectional area (CSA) in ET-1 treated animals compared with placebo. ET-1 treated animals showed significant increases in collagen synthesis (ten-fold) and collagen content (three-fold) compared to placebo treated animals. ET-1 treated animals also had a significant increase (two-fold) in proliferation rates. In addition, ET(A) and ET(B) receptor expression were significantly upregulated in ET-1 treated animals. By 10 weeks these stimulatory effects on intimal CSA and collagen content were no longer evident with a 'catch up' phenomenon observed in the placebo treated animals. Similarly, ET(A) and ET(B) mRNA levels had declined significantly in both groups. Therefore, exogenous ET-1 acutely stimulates extracellular and cellular processes including increased expression of ET(A) and ET(B) receptors contributing to intimal hyperplasia. However, these effects are transient and not maintained long term after withdrawal of exogenous ET-1 stimulation.

Differential effects of pentaerythritol tetranitrate and nitroglycerin on the development of tolerance and evidence of lipid peroxidation: a human in vivo study

OBJECTIVES

We investigated the development of nitrate tolerance after continuous exposure to nitroglycerin (GTN) as compared with pentaerythritol tetranitrate (PETN) in humans.

BACKGROUND

Sustained therapy with GTN causes tolerance and has been associated with increased production of free oxygen radicals by the endothelium. Pentaerythritol tetranitrate is an organic nitrate that has been used in the therapy of angina. There have been no investigations concerning the development of tolerance to PETN in humans. Animal investigations suggested that continuous therapy with PETN does not cause increased free radical production or hemodynamic tolerance.

METHODS

We randomized 30 healthy volunteers to continuous GTN (0.6 mg/h/24 h), long-acting PETN (60 mg orally three times a day) or no treatment (control group) for seven days. We studied systemic blood pressure responses and venous volume responses to GTN with strain-gauge plethysmography. The levels of cytotoxic aldehydes and isoprostanes were measured as markers of free radical-mediated lipid peroxidation.

RESULTS

Tolerance, as demonstrated by blood pressure and forearm plethysmography, developed in the GTN group and was absent in the PETN group (p < 0.05). Therapy with GTN was associated with a significant increase in plasma markers of lipid peroxidation. This response was not observed in those treated with PETN (isoprostanes: control: 38 +/- 5; GTN: 59 +/- 6; PETN: 38 +/- 3 microg/ml; p < 0.005).

CONCLUSIONS

Treatment with PETN does not cause tolerance and is not associated with evidence of increased free radical production.

Blockade of endothelin receptors markedly reduces atherosclerosis in LDL receptor deficient mice: role of endothelin in macrophage foam cell formation

OBJECTIVE

We evaluated the direct effects of long-term blockade of ET(A) and ET(B) receptors using a mixed endothelin (ET) receptor antagonist, LU224332, in the low density lipoprotein receptor (LDL-R) knockout mouse model of atherosclerosis.

METHODS

Four groups of LDL-R deficient mice were studied: control mice fed normal chow (group I); mice fed a high cholesterol (HC, 1.25%) diet alone (group II), HC fed animals treated with LU224332 (group III); and mice fed normal chow treated with the LU compound (group IV). All treatments were continued for 8 weeks at which time the animals were sacrificed and the aortae were removed and stained with oil red O. Atherosclerotic area (AA) was determined by quantitative morphometry and normalized relative to total aortic area (TA).

RESULTS

Cholesterol feeding resulted in a marked increased in total plasma cholesterol ( approximately 15 fold) and widespread aortic atherosclerosis (AA/TA: group I: 0.013+/-0.007; group II: 0.33+/-0. 11; P<0.001). Atherosclerotic lesions were characterized by immunohistochemistry as consisting mainly of macrophages which also showed high levels of ET-1 expression. Treatment with ET antagonist significantly reduced the development of atherosclerosis (AA/TA: group III: 0.19+/-0.07, P<0.01 vs. group II), without altering plasma cholesterol levels and blood pressure. The direct effect of LU224332 on macrophage activation and foam-cell formation was determined in vitro using a human macrophage cell line, THP-1. Treatment of the THP-1 cells with LU224332 significantly reduced cholesterol ester and triacylglycerol accumulation and foam-cell formation on exposure to oxidized LDL (P<0.01 and P<0.05, respectively).

CONCLUSION

We conclude that a nonselective ET receptor antagonist substantially inhibited the development of atherosclerosis in a genetic model of hyperlipidemia, possibly by inhibiting macrophage foam-cell formation, suggesting a role for these agents in the treatment and prevention of atherosclerotic vascular disease.

Homocysteine, lipoprotein(a), and restenosis after percutaneous transluminal coronary angioplasty: a prospective study

BACKGROUND

Restenosis complicates 30% to 40% of angioplasty procedures and may be unrelated to traditional coronary risk factors. Homocysteine, lipoprotein(a), and methylenetetrahydrofolate reductase (MTHFR 677T) (a genetic determinant of plasma homocysteine concentrations) are novel risk factors for coronary artery disease. Their roles in restenosis are unclear, and the potential synergism between homocysteine and lipoprotein(a) has not previously been studied. The objective of this study was to determine the relations among homocysteine, lipoprotein (a), MTHFR 677T, and restenosis after percutaneous transluminal coronary angioplasty.

METHODS

This prospective study enrolled patients with successful elective percutaneous transluminal coronary angioplasty or stenting of a single, de novo, native coronary lesion. Fasting blood was drawn the morning of the procedure for homocysteine, lipoprotein(a), and MTHFR 677T. Follow-up angiography was performed 6 months after the procedure or earlier if clinically indicated. All cineangiograms were analyzed quantitatively.

RESULTS

A total of 144 (92%) of 156 eligible patients underwent follow-up coronary angiography. The overall angiographic restenosis rate (residual stenosis >50%) was 31%. Mean homocysteine concentration was 10.1 +/- 3.7 micromol/L. Plasma homocysteine concentrations were not significantly different in patients with or without angiographic restenosis (9.6 +/- 3.3 vs 10.3 +/- 3.8 micromol/L; P =.31). Mean lipoprotein(a) concentration was 21.2 +/- 20.1 mg/dL. Plasma lipoprotein(a) concentrations were not significantly different in patients with or without restenosis (21.9 +/- 21.8 vs 20.9 +/- 19.5 mg/dL). Homozygosity for MTHFR 677T was present in 6.5% and was not associated with increased restenosis. No interaction between homocysteine and lipoprotein(a) was detected.

CONCLUSIONS

Homocysteine, lipoprotein(a), and MTHFR 677T are not associated with restenosis after percutaneous transluminal coronary angioplasty.

Role of nitric oxide in the angiogenic response in vitro to basic fibroblast growth factor

Angiogenesis is a complex process that involves the activation of quiescent endothelial cells (ECs) to a proliferative and migratory phenotype and, subsequently, their redifferentiation to form vascular tubes. We hypothesized that NO contributes to angiogenesis by terminating the proliferative action of angiogenic growth factors and initiating a genetic program of EC differentiation. Human umbilical vein ECs (HUVECs) and calf pulmonary artery ECs (CPAECs) were grown directly on plastic dishes or on three-dimensional fibrin matrices. In the absence of fibrin, treatment with NO-donor compounds, such as S-nitroso-N-acetylpenicillamine (SNAP, 0.1 and 0.4 mmol/L), produced a dose-dependent inhibition of proliferation in both cell lines, whereas the inhibition of endogenous NO production using NG-nitro-L-arginine methyl ester (L-NAME, 1 mmol/L) or NG-monomethyl-L-arginine (L-NMMA, 1 mmol/L) significantly increased proliferation of the CPAECs. The addition of basic fibroblast growth factor (bFGF, 30 ng/mL) increased the expression of endothelial NO synthase mRNA and the production of NO in both cell types when cultured on three-dimensional fibrin gels and produced profound morphological changes characterized by the appearance of extensive capillary-like vascular structures and the loss of EC monolayers. These changes were quantified by measuring total tube length per low-power field (x100), and a differentiation index was derived using the ratio of tube length over area covered by residual EC monolayer. In the absence of additional angiogenic factors, the differentiation index was low for both HUVECs and CPAECs (control, 1.16+/-0.19 and 2.07+/-0.87, respectively). Treatment with bFGF increased the differentiation index significantly in both cell types (10.59+/-2.03 and 20.02+/-5.01 for HUVECs and CPAECs, respectively; P<.05 versus control), and the addition of SNAP (0.4 mmol/L) mimicked the angiogenic response to bFGF (8.57+/-1.34 and 12.20+/-3.49 for HUVECs and CPAECs, respectively; P<.05 versus control). Moreover, L-NAME inhibited EC tube formation in response to bFGF in a dose-response manner, consistent with a role of endogenous NO production in EC differentiation in this angiogenic model. These findings suggest that NO may act as a crucial signal in the angiogenic response to bFGF, terminating the proliferative actions of angiogenic growth factors and promoting EC differentiation into vascular tubes.