Circ_0025039 acts an oncogenic role in the progression of non-small cell lung cancer through miR-636-dependent regulation of CORO1C

Non-small cell lung cancer remains the leading cause of cancer-related death worldwide. Circular RNA plays vital roles in NSCLC progression. This study is designed to reveal the role of circ_0025039 in NSCLC cell malignancy. The RNA expression of circ_0025039, microRNA-636 (miR-636), and coronin 1C was detected by quantitative real-time polymerase chain reaction. Protein expression was checked by Western blot analysis or immunohistochemistry assay. Cell proliferation, migration, invasion, tube formation ability, sphere formation capacity, and apoptosis were investigated by cell counting kit-8, 5-Ethynyl-29-deoxyuridine, transwell assay, tube formation assay, sphere formation assay, and flow cytometry analysis, respectively. Mouse model assay was conducted to reveal the effect of circ_0025039 silencing on tumor formation in vivo. The interaction between miR-636 and circ_0025039 or CORO1C was identified through dual-luciferase reporter and RNA pull-down assays. The expression of circ_0025039 and CORO1C was significantly increased, while miR-636 was decreased in NSCLC tissues and cells compared with controls. Circ_0025039 depletion repressed NSCLC cell proliferation, migration, invasion, tube-forming capacity, and sphere formation ability, but induced cell apoptosis. The neoplasm formation was repressed after circ_0025039 silencing. Additionally, circ_0025039 acted as a sponge for miR-636, which was found to target CORO1C. Importantly, the contribution of circ_0025039 to NSCLC progression was mediated by miR-636/CORO1C axis. Circ_0025039 silencing repressed NSCLC malignant progression by reducing CORO1C expression through miR-636, showing the possibility of circ_0025039 as a therapeutic target for NSCLC.

Oxytocin receptor disruption in Avil-expressing cells results in blunted sociability and increased inter-male aggression

Social behaviors are foundational to society and quality of life while social behavior extremes are core symptoms in a variety of psychopathologies and developmental disabilities. Oxytocin (OXT) is a neuroactive hormone that regulates social behaviors through its receptor (OXTR), with all previously identified social behavior effects attributed to the central nervous system, which has developmental origins in the neural tube. However, OXTR are also present in neural crest-derived tissue including sensory ganglia of the peripheral nervous system. Avil encodes for the actin-binding protein ADVILLIN, is expressed in neural crest-derived cells, and was therefore used as a target in this study to knock out OXTR expression in neural-crest derived cells. Here, we tested if OXTRs specifically expressed in Avil positive neural crest-derived cells are necessary for species-typical adult social behaviors using a Cre-LoxP strategy. Genetically modified male and female mice lacking OXTR in Avil expressing cells (OXTRAvil KO) were tested for sociability and preference for social novelty. Males were also tested for resident intruder aggression. OXTRAvil KO males and females had reduced sociability compared to OXTRAvil WT controls. Additionally, OXTRAvil KO males had increased aggressive behaviors compared to controls. These data indicate that OXTRs in cells of neural crest origin are important regulators of typical social behaviors in C57BL/6J adult male and female mice and point to needed directions of future research.

A peptide CORO1C-47aa encoded by the circular noncoding RNA circ-0000437 functions as a negative regulator in endometrium tumor angiogenesis

Circular RNAs (circRNAs) are a novel class of widespread noncoding RNAs that regulate gene expression in mammals. Recent studies demonstrate that functional peptides can be encoded by short open reading frames in noncoding RNAs, including circRNAs. However, the role of circRNAs in various physiological and pathological states, such as cancer, is not well understood. In this study, through deep RNA sequencing on human endometrial cancer (EC) samples and their paired adjacent normal tissues, we uncovered that the circRNA hsa-circ-0000437 is significantly reduced in EC compared with matched paracancerous tissue. The hsa-circ-0000437 contains a short open reading frame encoding a functional peptide termed CORO1C-47aa. Overexpression of CORO1C-47aa is capable of inhibiting angiogenesis at the initiation stage by suppressing endothelial cell proliferation, migration, and differentiation through competition with transcription factor TACC3 to bind to ARNT and suppress VEGF. CORO1C-47aa directly bound to ARNT through the PAS-B domain, and blocking the association between ARNT and TACC3, which led to reduced expression of VEGF, ultimately lead to reduced angiogenesis. The antitumor effects of CORO1C-47aa on EC progression suggest that CORO1C-47aa has potential value in anticarcinoma therapies and warrants further investigation.

Improvement Effects of Myelophil on Symptoms of Chronic Fatigue Syndrome in a Reserpine-Induced Mouse Model

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is associated with various symptoms, such as depression, pain, and fatigue. To date, the pathological mechanisms and therapeutics remain uncertain. The purpose of this study was to investigate the effect of myelophil (MYP), composed of Astragali Radix and Salviaemiltiorrhizae Radix, on depression, pain, and fatigue behaviors and its underlying mechanisms. Reserpine (2 mg/kg for 10 days, intraperitoneally) induced depression, pain, and fatigue behaviors in mice. MYP treatment (100 mg/kg for 10 days, intragastrically) significantly improved depression behaviors, mechanical and thermal hypersensitivity, and fatigue behavior. MYP treatment regulated the expression of c-Fos, 5-HT1A/B receptors, and transforming growth factor β (TGF-β) in the brain, especially in the motor cortex, hippocampus, and nucleus of the solitary tract. MYP treatment decreased ionized calcium binding adapter molecule 1 (Iba1) expression in the hippocampus and increased tyrosine hydroxylase (TH) expression and the levels of dopamine and serotonin in the striatum. MYP treatment altered inflammatory and anti-oxidative-related mRNA expression in the spleen and liver. In conclusion, MYP was effective in recovering major symptoms of ME/CFS and was associated with the regulation of dopaminergic and serotonergic pathways and TGF-β expression in the brain, as well as anti-inflammatory and anti-oxidant mechanisms in internal organs.

Assessment of cellular and molecular changes in the rat brain after gamma radiation and radioprotection by anisomycin

The objective of the study was to describe cellular and molecular markers of radioprotection by anisomycin, focusing on the changes in rat brain tissue. Two-month-old Wistar rats were exposed to a 60Co radiation source at a dose of 6 Gy, with or without radioprotection with anisomycin (150 mg/kg) administered subcutaneously 30 min before or 3 or 6 h after irradiation. Survivors were analyzed 30 days after treatment. Astroglial and microglial responses were investigated based on the expression of glial markers assessed with immunohistochemistry, and quantitative changes in brain biomolecules were investigated by Raman microspectroscopy. In addition, blood plasma levels of pro-inflammatory (interleukin 6 and tumor necrosis factor α) and anti-inflammatory (interleukin 10) cytokines were assessed. We found that application of anisomycin either before or after irradiation significantly decreased the expression of the microglial marker Iba-1. We also found an increased intensity of Raman spectral bands related to nucleic acids, as well as an increased level of cytokines when anisomycin was applied after irradiation. This suggests that the radioprotective effects of anisomycin are by decreasing Iba-1 expression and stabilizing genetic material by increasing the level of nucleic acids.

Preventing alloimmune rejection using circular RNA FSCN1-silenced dendritic cells in heart transplantation

BACKGROUND

While heart transplantation is used as a standard treatment for heart failure, transplant rejection continues to pose a challenge. Recent evidence has shown that circular RNA (circRNA) is a new type of gene regulator in cell development. Our aim was to demonstrate that treatment with tolerogenic dendritic cells (Tol-DCs) generated by circular RNA FSCN1 (circFSCN1) silencing could prevent alloimmune rejection and prolong heart graft survival in heart transplantation.

METHODS

Bone marrow-derived DCs were transfected with circFSCN1 siRNA in vitro. The circFSCN1 level was measured by qRT-PCR. DC maturation was determined by flow cytometry. Mixed lymphocyte reactions (MLRs) were conducted to assess the function of DCs to activate T cells and to generate regulatory T cells (Tregs). In situ RNA hybridization and fluorescent microscopy were performed to detect the distribution of circFSCN1 in DCs. A heterotopic allogeneic murine heart transplantation was conducted where recipients were pre-treated with donor derived circFSCN1-silenced Tol-DCs. Heartbeat was monitored to assess immune rejection.

RESULTS

Exonic circFSCN1 was highly expressed in the cytoplasm of mature DCs. Knockdown of circFSCN1 using siRNA arrested DCs at an immature state, impaired DC's ability to activate T cells and enhanced Treg generation. Treatment with circFSCN1-silenced Tol-DCs prevented alloimmune rejection, prolonged allograft survival, reduced fibrosis, and induced Tregs in vivo.

CONCLUSIONS

Knockdown of circFSCN1 induces Tol-DCs and treatment with these Tol-DCs prevents alloimmune rejection and prolongs allograft survival. This is a promising therapeutic target to combat transplant rejection in heart transplantation and increases our understanding of circRNA in the immune system.

Shen-Fu Decoction could ameliorate intestinal permeability by regulating the intestinal expression of tight junction proteins and p-VASP in septic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Shen-Fu Decoction (SFD), a classic Traditional Chinese paired herb formulation, has been widely used for the treatment of sepsis in China. This study was carried out to assess the effects of SFD in sepsis-induced intestinal permeability and intestinal epithelial tight junction damage in rats with sepsis.

MATERIALS AND METHODS

A rat model of sepsis was created by cecal ligation and puncture (CLP). Rats in Sham and CLP + vehicle groups received equal distilled water, while rats in SFD group were treated by gavage of SFD (3 mg/kg, twice a day) for 72h. Mortality, sepsis-induced peritoneal inflammation, intestinal and liver histopathology damage, intestinal permeability (serum FITC-dextran and D-lactate), serum LPS, serum inflammation (PCT, TNF-α, and IL-6), and liver function (AST and ALT) were evaluated. The levels of zonula occluden (ZO-1), Occludin, Claudin-1 were analyzed by Real-time quantitative PCR and Western blotting (WB) respectively. Vasodilator-stimulated phosphoprotein (VASP) and p-VASP in intestinal epithelium were analyzed by WB.

RESULTS

Our study showed that SFD markedly reduced the mortality rate of CLP rats, prevented intestine and liver damage, relieved sepsis-induced intestinal permeability and inflammation elevation, ameliorated sepsis-induced impaired intestinal permeability by regulating the expression of ZO-1, Occludin, Claudin-1 and p-VASP.

CONCLUSIONS

The herbal formula SFD may be useful for reducing sepsis-induced organic damage and mortality by ameliorating the condition of sepsis-induced intestinal permeability by regulating tight junction proteins and p-VASP.

CircMACF1 Attenuates Acute Myocardial Infarction Through miR-500b-5p-EMP1 Axis

It is widely accepted that circular RNA (circRNA) plays an important role in cardiovascular diseases. Therefore, this experiment aimed to investigate the pathogenesis of circMACF1 in acute myocardial infarction (AMI). qRT-PCR and immunoblotting were used to detect the expression levels of circMACF1, miR-500b-5p, and epithelial membrane protein 1 (EMP1). The role of circMACF1, miR-500b-5p, and EMP1 in cardiomyocyte apoptosis was assessed using annexin V-FITC/PI. Echocardiographic assessment, serum creatine kinase MB (CK-MB) and lactate dehydrogenase (LDH), myocardial infarct size, and TUNEL staining were applied in our research. In the MI group, the expression levels of circMACF1 and EMP1 were decreased with the increasing expression level of miR-500b-5p. CircMACF1 upregulated the expression of EMP1 as a sponge of miR-500b-5p, and circMACF1 was a direct target of miR-500b-5p. CircMACF1 impaired the progression of AMI by modulating the miR-500b-5p/EMP1 axis. CircMACF1 may be a potential therapeutic target for treating AMI. Graphical Abstract CircMACF1 upregulated EMP1 expression by sponge miR-500b-5p.

Down-regulation of long noncoding RNA PVT1 inhibits esophageal carcinoma cell migration and invasion and promotes cell apoptosis via microRNA-145-mediated inhibition of FSCN1

Accumulating evidence has established that long noncoding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) is a tumor regulator in many cancers. Here, we aimed to investigate the possible function of lncRNA PVT1 in esophageal carcinoma (EC) via targeting of microRNA-145 (miR-145). Initially, microarray-based gene expression profiling of EC was employed to identify differentially expressed genes. Moreover, the expression of lncRNA PVT1 was examined and the cell line presenting with the highest level of lncRNA PVT1 expression was selected for subsequent experiments. We then proceeded to examine interaction among lncRNA PVT1, FSCN1, and miR-145. The effect of lncRNA PVT1 on viability, migration, invasion, apoptosis, and tumorigenesis of transfected cells was examined with gain-of-function and loss-of-function experiments. We observed that lncRNA PVT1 was robustly induced in EC. lncRNA PVT1 could bind to miR-145 and regulate its expression, and FSCN1 is a target gene of miR-145. Overexpression of miR-145 or silencing of lncRNA PVT1 was revealed to suppress cell viability, migration, and invasion abilities, while also stimulating cell apoptosis. Furthermore, our in vivo results showed that overexpression of miR-145 or silencing of lncRNA PVT1 resulted in decreased tumor growth in nude mice. In conclusion, our research reveals that down-regulation of lncRNA PVT1 could potentially promote expression of miR-145 to repress cell migration and invasion, and promote cell apoptosis through the inhibition of FSCN1. This highlights the potential of lncRNA PVT1 as a therapeutic target for EC treatment.

Immunohistochemical negative expression of ezrin predicts poor prognosis in clear cell renal cell carcinoma

PURPOSE

To analyze the immunohistochemical expression of ezrin and moesin in clear cell renal cell carcinoma (ccRCC). These proteins, as part of the ezrin-radixin-moesin complex link the cell membrane to the actin cytoskeleton, affecting such processes as cell adhesion, cell survival, cell motility, and signal transduction. Our aim was to examine the impact of their expression on clinical outcomes and survival rates.

PATIENTS AND METHODS

Five hundred seventy-five consecutive patients who had been treated surgically for ccRCC in a single center between 1985 and 2016 were selected. A single pathologist reviewed all cases to perform a uniform reclassification and determined the most representative tumor areas for construction of a tissue microarray.

RESULTS

Of all ccRCC specimens, 106 (18.3%) were negative for ezrin, and 469 (81.7%) had positive ezrin expression; 16 (2.8%) were negative and 559 (97.2%) were positive for moesin, respectively. Ezrin expression was associated with pT stage (P < 0.001), clinical stage (P = 0.012), synchronic metastasis (P < 0.001), incidental tumors (P = 0.007), and International Society of Urological Pathology histological grade (P = 0.025). There was a correlation between moesin expression and clinical stage (P = 0.027), pT stage (P = 0.025), and pN stage (P = 0.007). Ezrin expression significantly influenced tumor-related deaths. By multivariate analysis, negative ezrin expression was an independent risk factor for disease-specific survival (HR 1.89; 95% CI 1.11-3.20).

CONCLUSIONS

Negativity for ezrin in ccRCC patients significantly impacts survival rates. We encourage further prospective studies to analyze ezrin analysis to evaluate its significance in the prognosis of ccRCC.

Anti-hyperalgesic effect of (-)-α-bisabolol and (-)-α-bisabolol/β-Cyclodextrin complex in a chronic inflammatory pain model is associated with reduced reactive gliosis and cytokine modulation

Chronic pain is a continuous or recurring pain which exceeds the normal course of recovery to an injury or disease. According to the origin of the chronic pain, it can be classified as inflammatory or neuropathic. This study aimed to evaluate the antinociceptive and anti-inflammatory effect of (-)-α-bisabolol (BIS) alone and complexed with β-cyclodextrin (βCD) in preclinical models of chronic pain. Chronic pain was induced by Freund's Complete Adjuvant (FCA) or partial lesion of the sciatic nerve (PLSN). Swiss mice were treated with BIS, BIS-βCD (50 mg/kg, p.o) or vehicle (control) and mechanical hyperalgesia, thermal hyperalgesia, muscle strength and motor coordination were evaluated. In addition, levels of TNF-α and IL-10 and expression of the ionized calcium-binding adapter protein (IBA-1) were assessed in the spinal cord of the mice. The complexation efficiency of BIS in βCD was evaluated by High-Performance Liquid Chromatography. BIS and BIS-βCD reduced (p < 0.001) mechanical and thermal hyperalgesia. No alterations were found in force and motor coordination. In addition, BIS and BIS-βCD inhibited (p < 0.05) TNF-α production in the spinal cord and stimulated (p < 0.05) the release of IL-10 in the spinal cord in PLSN-mice. Further, BIS and BIS-βCD reduced IBA-1 immunostaining. Therefore, BIS and BIS-βCD attenuated hyperalgesia, deregulated cytokine release and inhibited IBA-1 expression in the spinal cord in the PLSN model. Moreover, our results show that the complexation of BIS in βCD reduced the therapeutic dose of BIS. We conclude that BIS is a promising molecule for the treatment of chronic pain.

Characterization of leptomeningeal inflammation in rodent experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis

BACKGROUND

Leptomeningeal inflammation, as evidenced by leptomeningeal contrast enhancement (LMCE), is associated to cortical pathology in multiple sclerosis. The temporal pattern of LMCE in experimental autoimmune encephalomyelitis (EAE) myelin oligodendrocyte glycoprotein (MOG) is unknown.

OBJECTIVE

To investigate LMCE using serial MRI in the EAE model of MS, and its association with clinical disease progression. To characterize the relationship between LMCE and underlying histological correlates.

DESIGN

Thirteen C57BL/6J mice, MOG-immunized (35-55 amino acid) and 8 saline injected animals were assessed at pre-induction and at 3, 6, 10, 20, 27, 32, 45 and 63 days post induction (dPI). LMCE scan was obtained using FLAIR-RARE sequence after post-contrast gadolinium administration on 9.4 T scanner. Brain cryo-sections were assessed for measuring cellular density of Iba1 positive macrophage/microglia at 10 dPI and 32 dPI, and for the presence of T, B and macrophage cells in the meningeal layer at 10 dPI and 63 dPI.

RESULTS

All EAE-MOG animals showed presence of LMCE and none of the control mice. The peak signal intensity of LMCE was evidenced at 10dPI in the meninges and decreased through 10-63 dPI. The peak of LMCE was associated with a weight loss starting at 1 week PI and with clinical symptoms starting at 2 weeks PI. Histological analysis of the brain tissue showed a higher density of Iba1 positive microglial cells in the EAE-MOG animals, corresponding to the areas of LMCE. Meninges of EAE mice showed higher density of Iba1 stained macrophage cells relative to saline animals. EAE animals also showed the presence of T and B cells in the meninges which were absent in the saline animals.

CONCLUSIONS

LMCE peak intensity in the meninges corresponds to the acute inflammatory phase of EAE-MOG disease progression, and is associated with clinical symptoms and higher inflammatory cell density.

Long noncoding RNA NEXN-AS1 mitigates atherosclerosis by regulating the actin-binding protein NEXN

Noncoding RNAs are emerging as important players in gene regulation and disease pathogeneses. Here, we show that a previously uncharacterized long noncoding RNA, nexilin F-actin binding protein antisense RNA 1 (NEXN-AS1), modulates the expression of the actin-binding protein NEXN and that NEXN exerts a protective role against atherosclerosis. An expression microarray analysis showed that the expression of both NEXN-AS1 and NEXN was reduced in human atherosclerotic plaques. In vitro experiments revealed that NEXN-AS1 interacted with the chromatin remodeler BAZ1A and the 5' flanking region of the NEXN gene and that it also upregulated NEXN expression. Augmentation of NEXN-AS1 expression inhibited TLR4 oligomerization and NF-κB activity, downregulated the expression of adhesion molecules and inflammatory cytokines by endothelial cells, and suppressed monocyte adhesion to endothelial cells. These inhibitory effects of NEXN-AS1 were abolished by knockdown of NEXN. In vivo experiments using ApoE-knockout mice fed a Western high-fat diet demonstrated that NEXN deficiency promoted atherosclerosis and increased macrophage abundance in atherosclerotic lesions, with heightened expression of adhesion molecules and inflammatory cytokines, whereas augmented NEXN expression deterred atherosclerosis. Patients with coronary artery disease were found to have lower blood NEXN levels than healthy individuals. These results indicate that NEXN-AS1 and NEXN represent potential therapeutic targets in atherosclerosis-related diseases.

Expression and purification of human phosphatase and actin regulator 1 (PHACTR1) in plant-based systems

Cardiovascular diseases are a prevalent cause of morbidity and mortality especially in industrialized countries. The human phosphatase and actin regulator 1 (PHACTR1) may be involved in such diseases, but its precise regulatory function remains unclear due to the large number of potential interaction partners. The same phenomenon makes this protein difficult to express in mammalian cells, but it is also an intrinsically disordered protein that likely aggregates when expressed in bacteria due to the absence of chaperones. We therefore used a design of experiments approach to test the suitability of three plant-based systems for the expression of satisfactory quantities of recombinant PHACTR1, namely transient expression in tobacco (Nicotiana tabacum) BY-2 plant cell packs (PCPs), whole N. benthamiana leaves and BY-2 cell lysate (BYL). The highest yield was achieved using the BYL: up to 120 mg product kg-1 biomass equivalent within 48 h of translation. This was 1.3-fold higher than transient expression in N. benthamiana together with the silencing inhibitor p19, and 6-fold higher than the PCP system. The presence of Triton X-100 in the extraction buffer increased the recovery of PHACTR1 by 2-200-fold depending on the conditions. PHACTR1 was incompatible with biomass blanching and was stable for less than 16 h in raw plant extracts. Purification using a DDK-tag proved inefficient whereas 15% purity was achieved by immobilized metal affinity chromatography.

SOX9 is dispensable for the initiation of epigenetic remodeling and the activation of marker genes at the onset of chondrogenesis

SOX9 controls cell lineage fate and differentiation in major biological processes. It is known as a potent transcriptional activator of differentiation-specific genes, but its earliest targets and its contribution to priming chromatin for gene activation remain unknown. Here, we address this knowledge gap using chondrogenesis as a model system. By profiling the whole transcriptome and the whole epigenome of wild-type and Sox9-deficient mouse embryo limb buds, we uncover multiple structural and regulatory genes, including Fam101a, Myh14, Sema3c and Sema3d, as specific markers of precartilaginous condensation, and we provide evidence of their direct transactivation by SOX9. Intriguingly, we find that SOX9 helps remove epigenetic signatures of transcriptional repression and establish active-promoter and active-enhancer marks at precartilage- and cartilage-specific loci, but is not absolutely required to initiate these changes and activate transcription. Altogether, these findings widen our current knowledge of SOX9 targets in early chondrogenesis and call for new studies to identify the pioneer and transactivating factors that act upstream of or along with SOX9 to prompt chromatin remodeling and specific gene activation at the onset of chondrogenesis and other processes.

Deletion of the insulin receptor in sensory neurons increases pancreatic insulin levels

Insulin is known to have neurotrophic properties and loss of insulin support to sensory neurons may contribute to peripheral diabetic neuropathy (PDN). Here, genetically-modified mice were generated in which peripheral sensory neurons lacked the insulin receptor (SNIRKO mice) to determine whether disrupted sensory neuron insulin signaling plays a crucial role in the development of PDN and whether SNIRKO mice develop symptoms of PDN due to reduced insulin neurotrophic support. Our results revealed that SNIRKO mice were euglycemic and never displayed significant changes in a wide range of sensorimotor behaviors, nerve conduction velocity or intraepidermal nerve fiber density. However, SNIRKO mice displayed elevated serum insulin levels, glucose intolerance, and increased insulin content in the islets of Langerhans of the pancreas. These results contribute to the growing idea that sensory innervation of pancreatic islets is key to regulating islet function and that a negative feedback loop of sensory neuron insulin signaling keeps this regulation in balance. Our results suggest that a loss of insulin receptors in sensory neurons does not lead to peripheral nerve dysfunction. The SNIRKO mice will be a powerful tool to investigate sensory neuron insulin signaling and may give a unique insight into the role that sensory neurons play in modifying islet physiology.

Sustained Activation of Rho GTPases Promotes a Synthetic Pulmonary Artery Smooth Muscle Cell Phenotype in Neprilysin Null Mice

OBJECTIVE

Pulmonary artery smooth muscle cells (PASMCs) from neprilysin (NEP) null mice exhibit a synthetic phenotype and increased activation of Rho GTPases compared with their wild-type counterparts. Although Rho GTPases are known to promote a contractile SMC phenotype, we hypothesize that their sustained activity decreases SM-protein expression in these cells.

APPROACH AND RESULTS

PASMCs isolated from wild-type and NEP-/- mice were used to assess levels of SM-proteins (SM-actin, SM-myosin, SM22, and calponin) by Western blotting, and were lower in NEP-/- PASMCs compared with wild-type. Rac and Rho (ras homology family member) levels and activity were higher in NEP-/- PASMCs, and ShRNA to Rac and Rho restored SM-protein, and attenuated the enhanced migration and proliferation of NEP-/- PASMCs. SM-gene repressors, p-Elk-1, and Klf4 (Kruppel lung factor 4), were higher in NEP-/- PASMCs and decreased by shRNA to Rac and Rho. Costimulation of wild-type PASMCs with PDGF (platelet-derived growth factor) and the NEP substrate, ET-1 (endothelin-1), increased Rac and Rho activity, and decreased SM-protein levels mimicking the NEP knock-out phenotype. Activation of Rac and Rho and downstream effectors was observed in lung tissue from NEP-/- mice and humans with chronic obstructive pulmonary disease.

CONCLUSIONS

Sustained Rho activation in NEP-/- PASMCs is associated with a decrease in SM-protein levels and increased migration and proliferation. Inactivation of RhoGDI (Rho guanine dissociation inhibitor) and RhoGAP (Rho GTPase activating protein) by phosphorylation may contribute to prolonged activation of Rho in NEP-/- PASMCs. Rho GTPases may thus have a role in integration of signals between vasopeptides and growth factor receptors and could influence pathways that suppress SM-proteins to promote a synthetic phenotype.

Epithelial Cells Induce a Cyclo-Oxygenase-1-Dependent Endogenous Reduction in Airway Smooth Muscle Contractile Phenotype

Airway smooth muscle cells (ASMCs) are phenotypically regulated to exist in either a proliferative or a contractile state. However, the influence of other airway structural cell types on ASMC phenotype is largely unknown. Although epithelial cells are known to drive ASM proliferation, their effects on the contractile phenotype are uncertain. In the current study, we tested the hypothesis that epithelial cells reduce the contractile phenotype of ASMCs. To do so, we measured force production by traction microscopy, gene and protein expression, as well as calcium release by Fura-2 ratiometric imaging. ASMCs incubated with epithelial-derived medium produced less force after histamine stimulation. We observed reduced expression of myocardin, α-smooth muscle actin, and calponin within ASMCs after coculture with epithelial cells. Peak calcium release in response to histamine was diminished, and depended on the synthesis of cyclo-oxygenase-1 products by ASM and on prostaglandin E receptors 2 and 4. Together, these in vitro results demonstrate that epithelial cells have the capacity to coordinately reduce ASM contraction by functional antagonism and by reduction of the expression of certain contractile proteins.

Fascin Is Associated With Aggressive Behavior and Poor Outcome in Uterine Carcinosarcoma

OBJECTIVE

The mechanisms underlying the histogenesis and aggressiveness of uterine carcinosarcoma (UCS) are poorly understood; however, previous studies implicate epithelial-mesenchymal transition (EMT). Fascin is a proinvasive, actin-bundling protein and an important component of EMT. It is associated with poor outcomes in human carcinoma, especially in estrogen receptor (ER)-negative tumors arising in organs normally expressing ER. We sought to evaluate fascin expression in UCS and its relationship to ER status, clinicopathologic indicators of tumor aggressiveness, and survival outcomes.

METHOD

Forty-four surgically staged cases of UCS were immunohistochemically evaluated for fascin and estrogen receptor-α expression and correlated with clinicopathologic parameters derived from electronic medical records and pathology reports.

RESULTS

Fascin was only expressed in malignant epithelium and mesenchyma and was uniformly absent in background benign counterparts. Increased expression was associated with extrapelvic disease (P = 0.028), higher stage (P = 0.021), larger tumor size (P = 0.032), shorter progression-free interval (P = 0.035), and reduced estrogen receptor-α expression (P = 0.04).

CONCLUSION

Fascin is aberrantly expressed in both elements of UCS and is associated with aggressive behavior and worse outcome. As a component of EMT and mediator of invasion, fascin may serve as a target in future therapies.

Aberrant expression of FLI-1 in melanoma

Friend leukemia integration site 1 (FLI-1) nuclear transcription factor has been proposed as a suitable tool in the differential diagnosis of small round cell sarcomas. It has also been described as a nuclear marker of endothelial differentiation. Expression of FLI-1 has been demonstrated in Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) and vascular neoplasms. In the present study, we describe 2 cases of metastatic melanoma with small round blue cell morphology that showed strong nuclear expression of FLI-1. Because of the small round blue cell morphology and negative immunohistochemical staining for pan-melanocytic cocktail (HMB45, anti MART1 and anti-tyrosinase) and SOX10 in both cases, FLI-1 immunostaining was requested as part of the tumors workup. Ultimately, both cases were established as being metastatic melanoma. Dermatopathologists should be aware that melanoma can be strongly positive for FLI-1 and not misinterpret these cases for ES/PNET or vascular lesions, especially when melanomas show unusual morphology.

Knockdown of calponin 2 suppressed cell growth in gastric cancer cells

Calponin family members are actin filament-associated regulatory proteins with distinct expression patterns. Previous studies on CNN2 (calponin 2) have demonstrated that CNN2 is expressed in a broad range of tissues and cell types, exhibiting potential regulatory roles in a number of cellular activities, including cell proliferation, cell migration, and platelet adhesion. In this work, we found that both messenger RNA and protein expression levels of CNN2 were remarkably upregulated in 60%-70% of gastric cancer tissues by comparison with those of neighboring non-tumorous mucosa. By utilizing specific shCNN2 (small hairpin RNA targeting CNN2), the potential role of CNN2 in regulating AGS gastric cancer cell growth was then further investigated. AGS cells infected with shCNN2 exhibited significantly decreased cell growth ability by comparison with control cells in vitro. Moreover, while there was no obvious difference in cell cycle distribution between two groups, enhanced cell apoptosis was detected in cells with reduced CNN2 expression. Consistently, caspase 3/7 activity was also remarkably activated upon shCNN2 lentivirus infection. Taken together, our results demonstrated that knockdown of endogenous CNN2 in AGS cells could significantly activate cell apoptosis pathway and therefore suppress cell growth in vitro. The deletion of CNN2 might be a potential therapeutic approach to inhibit aggressive growth of gastric cancer.

PHACTR1 Is a Genetic Susceptibility Locus for Fibromuscular Dysplasia Supporting Its Complex Genetic Pattern of Inheritance

Fibromuscular dysplasia (FMD) is a nonatherosclerotic vascular disease leading to stenosis, dissection and aneurysm affecting mainly the renal and cerebrovascular arteries. FMD is often an underdiagnosed cause of hypertension and stroke, has higher prevalence in females (~80%) but its pathophysiology is unclear. We analyzed ~26K common variants (MAF>0.05) generated by exome-chip arrays in 249 FMD patients and 689 controls. We replicated 13 loci (P<10-4) in 402 cases and 2,537 controls and confirmed an association between FMD and a variant in the phosphatase and actin regulator 1 gene (PHACTR1). Three additional case control cohorts including 512 cases and 669 replicated this result and overall reached the genomic level of significance (OR = 1.39, P = 7.4×10-10, 1,154 cases and 3,895 controls). The top variant, rs9349379, is intronic to PHACTR1, a risk locus for coronary artery disease, migraine, and cervical artery dissection. The analyses of geometrical parameters of carotids from ~2,500 healthy volunteers indicate higher intima media thickness (P = 1.97×10-4) and wall to lumen ratio (P = 0.002) in rs9349379-A carriers, suggesting indices of carotid hypertrophy previously described in carotids of FMD patients. Immunohistochemistry detected PHACTR1 in endothelium and smooth muscle cells of FMD and normal human carotids. The expression of PHACTR1 by genotypes in primary human fibroblasts showed higher expression in rs9349379-A carriers (N = 86, P = 0.003). Phactr1 knockdown in zebrafish resulted in dilated vessels indicating subtle impaired vascular development. We report the first susceptibility locus for FMD and provide evidence for a complex genetic pattern of inheritance and indices of shared pathophysiology between FMD and other cardiovascular and neurovascular diseases.

Tensin Is Expressed in Glomerular Mesangial Cells and Is Related to Their Attachment to Surrounding Extracellular Matrix

Glomerular expression of tensin was immunohistochemically studied in normal and diseased rat kidneys to determine whether tensin might be related to specific binding in individual glomerular cells. Normal rat kidneys displayed an intense immunofluorescence reaction for tensin along the basal aspects of proximal and distal tubule cells and parietal epithelial cells of Bowman's capsules. In glomeruli, a positive reaction for tensin was detected only in the mesangial areas. Immunoelectron microscopy revealed a positive reaction in the mesangial cell (MC) processes. RT-PCR and immunoprecipitation demonstrated mRNA and protein levels of tensin in cultured rat MCs. Mesangial tensin expression was decreased when the mesangium was injured by Habu snake venom. During the regenerative process after mesangiolysis, tensin expression was not detected in early-phase proliferating MCs that did not have extracellular matrix (ECM). The expression of tensin recovered in late-phase proliferating MCs, which became attached to regenerated ECM. It appears that tensin is related to MC attachment to surrounding ECM, which suggests that signal transduction regulated by tensin may be related to a specific mechanism of MC matrix regeneration. Furthermore, tensin can act as a marker for rat MCs because the expression of tensin was detected only in MCs in glomeruli.

PDLIM2 suppression efficiently reduces tumor growth and invasiveness of human castration-resistant prostate cancer-like cells

BACKGROUND

Although PDLIM2 gene may have a context-dependent role in various human malignancies and can be a potential therapeutic target, only a limited number of in vitro studies addressed the molecular functions of PDLIM2 in prostate cancer. Here, we aimed to explore the role of PDLIM2 and the effect of the PDLIM2 gene suppression on oncogenic phenotypes of human castration-resistant prostate cancer (CRPC)-like cells.

METHODS

We used human CRPC-like cell lines (PC3, DU145, and C4-2B) for our experiments. Transcription levels of PDLIM2 and relevant genes were measured by real time-PCR and protein expression was analyzed by western blot. Cell viability, proliferation, clonogenic growth, and tumor sphere formation were examined after a specific inhibition of PDLIM2 using RNA interference. Flow cytometry was used to examine apoptotic cell death and cell cycle disturbances. Wound healing and transwell migration assays were performed to investigate the invasion capabilities of CRPC-like cells. Additionally, key oncogenic signaling pathways were examined using western blot. Lastly, we evaluated the in vivo efficacy of PDLIM2 suppression on tumor growth of human CRPC xenografts in mice.

RESULTS

We observed a significant enhancement of PDLIM2 expression in human CRPC-like cell lines, while a specific inhibition of PDLIM2 reduced cell viability and proliferation due to apoptotic cell death. Conversely, PDLIM2 overexpression significantly reduced cell proliferation compared to the negative control in androgen-sensitive LNCaP cells. Moreover, PDLIM2 suppression led to a decrease of clonogenic growth and tumor sphere formation in three-dimensional cultures with the G2/M cell cycle arrest in human CRPC-like cells. PDLIM2 inhibition also attenuated cellular migration and invasion capabilities of human CRPC-like cells, and reduced the expression of mesenchymal marker. Among several oncogenic signaling pathways, only the MAPK/ERK signaling cascade was decreased by PDLIM2 inhibition and reciprocally, ERK inhibition down-regulated PDLIM2 expression. Importantly, PDLIM2 inhibition remarkably compromised tumor growth in a human CRPC xenograft model.

CONCLUSION

In summary, the suppression of PDLIM2 significantly reduced such oncogenic phenotypes as proliferation, clonogenicity, invasiveness, and tumor cell growth in human CRPC-like cells both in vitro and in vivo, indicating that PDLIM2 may be considered a novel therapeutic target gene for treating human CRPC.

Potentially positive ageing-related variations of medial smooth muscle cells in the saphenous veins used as aortocoronary bypass grafts

INTRODUCTION

Currently, elderly people constitute a large proportion of patients undergoing coronary artery bypass grafting (CABG). Activated smooth muscle cells in the tunica media of saphenous vein (SV) grafts are thought to play a key role in the formation of neointima and development of occluding atherosclerotic plaques. The aim of this study was to identify ageing-related variations in the expression of the smooth muscle cells pro-teins that may impact on patency rate of the grafts and the CABG outcomes.

MATERIAL AND METHODS

The study involved 216 consecutive patients with the mean of 62.7 ± 8.4 years who underwent isolated CABG with at least one SV aortocoronary bypass graft. Expression of a-smooth muscle actin (a-SM actin), smooth muscle-myosin heavy chain (SM-MHC), calponin (CALP), cytokeratin 8 (CK-8), metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinases-2 and -3 (TIMP-2, TIMP-3) in the SV wall was assessed by immunohistochemistry and correlated with the age of patients.

RESULTS

Calponin and a-SM actin were expressed in all studied SV transplants. SM-MHC immunoreactivity was observed in SV segments in 68.5% of patients, whereas MMP-2a and TIMPs expression was found in 75% of cases. In more than 50% of analyzed SV transplants, no expression of cytokeratin-8 was found. Moderate correlations between preexisting expressions of either cytoskeletal or hemostatic proteins in the tunica media of the SV grafts and the age of CABG patients were demonstrated. They were positive for SM-MHC (r = 0.494), CALP (r = 0.548), TIMP-2 (r = 0.413) and TIMP-3 (r = 0.406) whereas negative for CK-8 (r = -0.528) and MMP-2 (r = -0.417).

CONCLUSIONS

Age-dependent decreases in the expression of MMP-2 and CK-8 accompanied by increases in expression of SM-MHC, TIMP-2 and TIMP-3 may promote SV graft patency and, thus, suggest a rationale for common use of SV grafts in the elderly.

[Analysis of Phenotypic Manifestation of peanut Gene Expression Suppression by RNAi in Drosophila Oogenesis]

The peanut gene functions in Drosophila melanogaster oogenesis were studied. It was demonstrated that the suppression of peanut expression by RNA interference in the ovary follicular cells results in the violation of oocyte polarization, anomalous cytokinesis in the chorion cells, and violation of the chromatin condensation in follicular cells. No oogenesis violations were observed in females with decreased peanut gene expression or an absence of the Pnut protein in the ovary generative cells. However, embryos produced by such females had a decreased survival rate caused by two death peaks.

BSND and ATP6V1G3: Novel Immunohistochemical Markers for Chromophobe Renal Cell Carcinoma

Differentiating between chromophobe renal cell carcinoma (RCC) and other RCC subtypes can be problematic using routine light microscopy. This study aimed to identify novel immunohistochemical markers useful for a differential diagnosis between chromophobe RCC and other RCC subtypes. We selected 3 genes (including BSND and ATP6V1G3) that showed specific transcriptional expression in chromophobe RCC using expression data (n = 783) from The Cancer Genome Atlas (TCGA) database. A subsequent immunohistochemical examination of 186 RCCs obtained in our patient series resulted in a strong diffuse positivity of BSND and ATP6V1G3 proteins (both of which are involved in the regulation of membrane transport) in all the chromophobe RCC specimens (23/23 cases, 100%) but not in the clear cell RCC specimens (0/153 cases, 0%) or the papillary RCC specimens (0/10 cases, 0%). BSND and ATP6V1G3 protein expressions were also detected in renal oncocytoma (13/14 cases, 92.9%) and in the distal nephron, including the collecting duct, in the normal kidney. A computational analysis of TCGA data suggested that DNA methylation was involved in the differential expression pattern of both genes among RCC subtypes. Finally, an immunohistochemical analysis showed lung carcinomas were negative (0/85 cases, 0%) for the expression of both proteins. These results suggest that BSND and ATP6V1G3 are excellent novel immunohistochemical markers for differentiating between chromophobe RCC and other subtypes of RCC, including clear cell and papillary RCCs.

[Association of intracellular proteinase activities with the content of locomotor proteins in tissues of primary tumors and metastasis in ovarian cancer]

The ability to active movement in extracellular matrix wherein significant role plays remodeling of the cytoskeleton by actin-binding proteins may influence on the metastatic potential of tumor cells. We studied the expression of actin-binding proteins and β-catenin in connection with proteasome and calpain functioning in the tissues of primary tumors and metastases of ovarian cancer. The chymotrypsin-like proteasome activity and calpain activity were shown to be significantly higher in ovarian cancer than in normal tissues. Furthermore, the activity of the proteasome and calpain were significantly higher in the peritoneal metastases in comparison with primary tumors. Correlation analysis showed in the primary tumor tissue the presence of a positive relationship between the activity of calpain and chymotrypsin-like proteasome activity (r = 0.82; p = 0.0005), whereas in metastases this connection was not revealed. Contents of p45 Ser β-catenin and the actin-severing protein gelzolin were decreased in metastases relative to primary tumors. Level of cofilin, functionally similar to gelzolin protein, was significantly higher in metastases compared to primary ovarian tumor tissue. In ovarian cancer significant reduction in the number of the monomer binder protein thymosin-β4 was observed in primary tumors and metastases as compared to normal tissues, but significant differences between the primary tumor and metastases were not observed. In the tissues of primary tumors negative correlations were observed between the chymotrypsin-like activity of the proteasome and the amount of p45 Ser β-catenin and protein Arp3, a member of the Arp2/3 complex. In metastasis negative correlation were revealed between the activity of calpain and content Arp3, cofilin, thymosin. The data obtained suggest the existence of different mechanisms of proteolytic regulation of locomotor proteins in primary tumors and metastases in ovarian cancer.

PKCε is a negative regulator of PVAT-derived vessel formation

RATIONALE

Vessel formation is a crucial event in tissue repair after injury. Thus, one assumption of innovative therapeutic approaches is the understanding of its molecular mechanisms. Notwithstanding our knowledge of the role of Protein Kinase C epsilon (PKCε) in cardio-protection and vascular restenosis, its role in vessel progenitor differentiation remains elusive.

OBJECTIVE

Given the availability of PKCε pharmacological modulators already tested in clinical trials, the specific aim of this study is to unravel the role of PKCε in vessel progenitor differentiation, with implications in vascular pathology and vasculogenesis.

METHODS AND RESULTS

Mouse Peri-Vascular Adipose Tissue (PVAT) was used as source of mesenchymal vessel progenitors. VEGF-induced differentiation of PVAT cells down-regulates both PKCε and p-PAK1 protein expression levels. PKCε overexpression and activation: i) reduced the expression levels of SMA and PECAM in endothelial differentiation of PVAT cells; ii) completely abrogated tubules formation in collagen gel assays; iii) increased the expression of p-PAK1.

CONCLUSION

PKCε negatively interferes with vessel progenitor differentiation via interaction with PAK-1.

Effects of DNA damage in smooth muscle cells in atherosclerosis

RATIONALE

DNA damage and the DNA damage response have been identified in human atherosclerosis, including in vascular smooth muscle cells (VSMCs). However, although double-stranded breaks (DSBs) are hypothesized to promote plaque progression and instability, in part, by promoting cell senescence, apoptosis, and inflammation, the direct effects of DSBs in VSMCs seen in atherogenesis are unknown.

OBJECTIVE

To determine the presence and effect of endogenous levels of DSBs in VSMCs on atherosclerosis.

METHODS AND RESULTS

Human atherosclerotic plaque VSMCs showed increased expression of multiple DNA damage response proteins in vitro and in vivo, particularly the MRE11/RAD50/NBS1 complex that senses DSB repair. Oxidative stress-induced DSBs were increased in plaque VSMCs, but DSB repair was maintained. To determine the effect of DSBs on atherosclerosis, we generated 2 novel transgenic mice lines expressing NBS1 or C-terminal deleted NBS1 only in VSMCs, and crossed them with apolipoprotein E(-/-) mice. SM22α-NBS1/apolipoprotein E(-/-) VSMCs showed enhanced DSB repair and decreased growth arrest and apoptosis, whereas SM22α-(ΔC)NBS1/apolipoprotein E(-/-) VSMCs showed reduced DSB repair and increased growth arrest and apoptosis. Accelerating or retarding DSB repair did not affect atherosclerosis extent or composition. However, VSMC DNA damage reduced relative fibrous cap areas, whereas accelerating DSB repair increased cap area and VSMC content.

CONCLUSIONS

Human atherosclerotic plaque VSMCs show increased DNA damage, including DSBs and DNA damage response activation. VSMC DNA damage has minimal effects on atherogenesis, but alters plaque phenotype inhibiting fibrous cap areas in advanced lesions. Inhibiting DNA damage in atherosclerosis may be a novel target to promote plaque stability.

T-plastin expression downstream to the calcineurin/NFAT pathway is involved in keratinocyte migration

Cutaneous wound healing requires keratinocyte proliferation, migration and differentiation to restore the barrier function of the skin. The calcineurin/nuclear factor of activated-T-cell (NFAT) signaling pathway has been recently shown to be involved in keratinocyte growth, differentiation and migration. It is induced by an increased intracellular calcium rate and its inhibition results in decreased capacities of keratinocytes to migrate. Nevertheless, the link between calcineurin activation and keratinocyte migration remains unknown. Recently, Orai1, a pore subunit of a store-operated calcium channel that favors calcium influx, was shown to play a critical role to control proliferation and migration of basal keratinocytes. Of interest, the actin-bundling T-plastin is crucial in cell motility through cross-linking to actin filament and its synthesis was shown to be induced by calcium influx and regulated by the calcineurin/NFAT pathway in tumor Sezary cells. We investigated herein the role of the calcineurin/NFAT pathway-dependent T-plastin in keratinocyte migration, by quantifying T-plastin expression in keratinocytes and by analyzing their migration under calcineurin inhibition or knockdown of NFAT2 or T-plastin. We did confirm the role of the calcineurin/NFAT pathway in keratinocyte migration as shown by their decreased capacities to migrate after FK506 treatment or siNFAT2 transfection in both scratching and Boyden assays. The expression of NFAT2 and T-plastin in keratinocytes was decreased under FK506 treatment, suggesting that T-plastin plays a role in keratinocyte migration downstream to the calcineurin/NFAT pathway. Accordingly, siRNA knockdown of T-plastin expression also decreased their migration capacities. Actin lamellipodia formation as well as FAK and β6-integrin expression were also significantly decreased after treatment with FK506 or siRNA, reinforcing that NFAT2-dependent T-plastin expression plays a role in keratinocyte migration. These results indicate that T-plastin might be considered as a major actor in the mechanisms underlying calcineurin/NFAT-dependent keratinocyte migration and may explain wound-healing defects observed in patients under calcineurin inhibitor long-term treatment.

Polarity gene alterations in pure invasive micropapillary carcinomas of the breast

INTRODUCTION

Pure invasive micropapillary carcinoma (IMPC) is a special type of breast carcinoma characterised by clusters of cells presenting polarity abnormalities. The biological alterations underlying this pattern remain unknown.

METHODS

Pangenomic analysis (n=39), TP53 (n=43) and PIK3CA (n=41) sequencing in a series of IMPCs were performed. A subset of cases was also analysed with whole-exome sequencing (n=4) and RNA sequencing (n=6). Copy number variation profiles were compared with those of oestrogen receptors and grade-matched invasive ductal carcinomas (IDCs) of no special type.

RESULTS

Unsupervised analysis of genomic data distinguished two IMPC subsets: one (Sawtooth/8/16) exhibited a significant increase in 16p gains (71%), and the other (Firestorm/Amplifier) was characterised by a high frequency of 8q (35%), 17q (20% to 46%) and 20q (23% to 30%) amplifications and 17p loss (74%). TP53 mutations (10%) were more frequently identified in the amplifier subset, and PIK3CA mutations (4%) were detected in both subsets. Compared to IDC, IMPC exhibited specific loss of the 6q16-q22 region (45%), which is associated with downregulation of FOXO3 and SEC63 gene expression. SEC63 and FOXO3 missense mutations were identified in one case each (2%). Whole-exome sequencing combined with RNA sequencing of IMPC allowed us to identify somatic mutations in genes involved in polarity, DNAH9 and FMN2 (8% and 2%, respectively) or ciliogenesis, BBS12 and BBS9 (2% each) or genes coding for endoplasmic reticulum protein, HSP90B1 and SPTLC3 (2% each) and cytoskeleton, UBR4 and PTPN21 (2% each), regardless of the genomic subset. The intracellular biological function of the mutated genes identified by gene ontology analysis suggests a driving role in the clinicopathological characteristics of IMPC.

CONCLUSION

In our comprehensive molecular analysis of IMPC, we identified numerous genomic alterations without any recurrent fusion genes. Recurrent somatic mutations of genes participating in cellular polarity and shape suggest that they, together with other biological alterations (such as epigenetic modifications and stromal alterations), could contribute to the morphological pattern of IMPC. Though none of the individual abnormalities demonstrated specificity for IMPC, whether their combination in IMPC may have a cumulative effect that drives the abnormal polarity of IMPC needs to be examined further with in vitro experiments.

Cardiac fibroblast-derived microRNA passenger strand-enriched exosomes mediate cardiomyocyte hypertrophy

In response to stress, the heart undergoes extensive cardiac remodeling that results in cardiac fibrosis and pathological growth of cardiomyocytes (hypertrophy), which contribute to heart failure. Alterations in microRNA (miRNA) levels are associated with dysfunctional gene expression profiles associated with many cardiovascular disease conditions; however, miRNAs have emerged recently as paracrine signaling mediators. Thus, we investigated a potential paracrine miRNA crosstalk between cardiac fibroblasts and cardiomyocytes and found that cardiac fibroblasts secrete miRNA-enriched exosomes. Surprisingly, evaluation of the miRNA content of cardiac fibroblast-derived exosomes revealed a relatively high abundance of many miRNA passenger strands ("star" miRNAs), which normally undergo intracellular degradation. Using confocal imaging and coculture assays, we identified fibroblast exosomal-derived miR-21_3p (miR-21*) as a potent paracrine-acting RNA molecule that induces cardiomyocyte hypertrophy. Proteome profiling identified sorbin and SH3 domain-containing protein 2 (SORBS2) and PDZ and LIM domain 5 (PDLIM5) as miR-21* targets, and silencing SORBS2 or PDLIM5 in cardiomyocytes induced hypertrophy. Pharmacological inhibition of miR-21* in a mouse model of Ang II-induced cardiac hypertrophy attenuated pathology. These findings demonstrate that cardiac fibroblasts secrete star miRNA-enriched exosomes and identify fibroblast-derived miR-21* as a paracrine signaling mediator of cardiomyocyte hypertrophy that has potential as a therapeutic target.

Mechanoregulation of h2-calponin gene expression and the role of Notch signaling

The essential role of mechanical signals in regulating the function of living cells is universally observed. However, how mechanical signals are transduced in cells to regulate gene expression is largely unknown. We previously demonstrated that the gene encoding h2-calponin (Cnn2) is sensitively regulated by mechanical tension. In the present study, mouse genomic DNA containing the Cnn2 promoter was cloned, and a nested set of 5' truncations was studied. Transcriptional activity of the Cnn2 promoter-reporter constructs was examined in transfected NIH/3T3, HEK293, and C2C12 cells for their responses to the stiffness of culture substrate. The results showed significant transcriptional activities of the -1.00- and -1.24-kb promoter constructs, whereas the -0.61-kb construct was inactive. The -1.38-, -1.57-, and -2.12-kb constructs showed higher transcriptional activity, whereas only the -1.57- and -2.12-kb constructs exhibited repression of expression when the host cells were cultured on low stiffness substrate. Internal deletion of the segment between -1.57 and -1.38 kb in the -2.12-kb promoter construct abolished the low substrate stiffness-induced repression. Site-specific deletion or mutation of an HES-1 transcription factor binding site in this region also abolished this repression effect. The level of HES-1 increased in cells cultured under a low tension condition, corresponding to the down-regulation of h2-calponin. h2-Calponin gene expression is further affected by the treatment of cells with Notch inhibitor and activator, suggesting an upstream signaling mechanism.

Changes in the expression of smooth muscle contractile proteins in TNBS- and DSS-induced colitis in mice

Thin filament-associated proteins such as calponin, caldesmon, tropomyosin, and smoothelin are thought to regulate acto-myosin interaction and thus, muscle contraction. However, the effect of inflammation on the expression of thin filament-associated proteins is not known. The aim of the present study is to determine the changes in the expression of calponin, caldesmon, tropomyosin, and smoothelin in colonic smooth muscle from trinitrobenzene sulphonic acid (TNBS)- and dextran sodium sulphate (DSS)-induced colitis in mice. Expression of h-caldesmon, h2-calponin, α-tropomyosin, and smoothelin-A was measured by qRT-PCR and Western blot. Contraction in response to acetylcholine in dispersed muscle cells was measured by scanning micrometry. mRNA and protein expression of α-actin, h2-calponin, h-caldesmon, smoothelin, and α-tropomyosin in colonic muscle strips from mice with TNBS- or DSS-induced colitis was significantly increased compared to control animals. Contraction in response to acetylcholine was significantly decreased in muscle cells isolated from inflamed regions of TNBS- or DSS-treated mice compared to control mice. Our results show that increase in the expression of thin filament-associated contractile proteins, which inhibit acto-myosin interaction, could contribute to decrease in smooth muscle contraction in inflammation.

Hypertensive changes within the aortic arch of infants and children with isolated coarctation

BACKGROUND

Despite repair, a significant proportion of patients with coarctation of the aorta (CoA) present with late hypertension. Increased gene expression of aortic wall collagen and vascular smooth muscle cell markers occurs in the presence of hypertension. Before repair, a patent ductus arteriosus (PDA) limits hypertension proximal to the coarctation. We hypothesize that preoperative collagen and vascular smooth muscle expression from the aortic arch in children is variable, depending on the presence or absence of a PDA.

METHODS

We analyzed the expression patterns of collagen and vascular smooth muscle cell markers in 25 children with CoA using a quantitative polymerase chain reaction. Aortic arch tissue proximal to the CoA was normalized to descending aortic tissue distal to the coarctation. Collagen-I, transforming growth factor-β, elastin, and calponin were analyzed.

RESULTS

At repair, 19 patients were aged younger than 3 months (14 with a PDA, 5 with a ligamentum arteriosum), and the remaining 6 were older than 1 year. There was no difference in age or weight between infants with or without a PDA. Infants without a PDA had the greatest difference in collagen-I expression compared with infants with a PDA (7.0 ± 1.6-fold vs 0.8 ± 1.1-fold, p = 0.01). Expression of transforming growth factor-β (4.3 ± 1.4 vs 2.6 ± 2.3, p = 0.01) and calponin (3.7 ± 0.7 vs 0.6 ± 1.1, p = 0.05) was lower from infants with vs without a PDA.

CONCLUSIONS

Our findings provide evidence of preoperative changes in the aortic arch before repair, particularly in the absence of a PDA.

WDR1 expression in normal and noise-damaged Sprague-Dawley rat cochleae

WD40 repeat protein 1 (WDR1) has been suggested as a protective mechanism or a sign of regeneration in avian cochlea. However, its role in mammalian cochlea has yet to be determined. Hence, we investigated WDR1 expression in sound-overstimulated Sprague-Dawley rats. Rats were divided into three groups (the permanent and temporary threshold shift [PTS and TTS] groups and the control group) according to the extent of noise exposure and euthanized immediately, 3, or 7 days after noise exposure for cochlear harvest. Immunocytochemistry localized WDR1 to outer hair cells, Deiter's cells, outer sulcus cells, and Reissner's membrane in the control group, and the PTS and TTS groups exhibited stronger WDR1 expression in the same cochlear regions than the controls. Moreover, WDR1 expression in these noise-exposed groups was extended to inner hair cells and basal cells of the stria vascularis. The expression of WDR1 in the PTS and TTS groups showed differences in intensity and shifts of localization, based on exposure length and recovery duration. Contrary to the avian cochlea, hair cell regeneration does not naturally occur in the acoustically damaged mammalian cochlea. Therefore, elevated WDR1 expression after acoustic overstimulation in the current experiments may provide a mechanism for protection against noise exposure.

Network-based survival analysis reveals subnetwork signatures for predicting outcomes of ovarian cancer treatment

Cox regression is commonly used to predict the outcome by the time to an event of interest and in addition, identify relevant features for survival analysis in cancer genomics. Due to the high-dimensionality of high-throughput genomic data, existing Cox models trained on any particular dataset usually generalize poorly to other independent datasets. In this paper, we propose a network-based Cox regression model called Net-Cox and applied Net-Cox for a large-scale survival analysis across multiple ovarian cancer datasets. Net-Cox integrates gene network information into the Cox's proportional hazard model to explore the co-expression or functional relation among high-dimensional gene expression features in the gene network. Net-Cox was applied to analyze three independent gene expression datasets including the TCGA ovarian cancer dataset and two other public ovarian cancer datasets. Net-Cox with the network information from gene co-expression or functional relations identified highly consistent signature genes across the three datasets, and because of the better generalization across the datasets, Net-Cox also consistently improved the accuracy of survival prediction over the Cox models regularized by or . This study focused on analyzing the death and recurrence outcomes in the treatment of ovarian carcinoma to identify signature genes that can more reliably predict the events. The signature genes comprise dense protein-protein interaction subnetworks, enriched by extracellular matrix receptors and modulators or by nuclear signaling components downstream of extracellular signal-regulated kinases. In the laboratory validation of the signature genes, a tumor array experiment by protein staining on an independent patient cohort from Mayo Clinic showed that the protein expression of the signature gene FBN1 is a biomarker significantly associated with the early recurrence after 12 months of the treatment in the ovarian cancer patients who are initially sensitive to chemotherapy. Net-Cox toolbox is available at http://compbio.cs.umn.edu/Net-Cox/.

Network-based computational models are attracting increasing attention in studying cancer genomics because molecular networks provide valuable information on the functional organizations of molecules in cells. Survival analysis mostly with the Cox proportional hazard model is widely used to predict or correlate gene expressions with time to an event of interest (outcome) in cancer genomics. Surprisingly, network-based survival analysis has not received enough attention. In this paper, we studied resistance to chemotherapy in ovarian cancer with a network-based Cox model, called Net-Cox. The experiments confirm that networks representing gene co-expression or functional relations can be used to improve the accuracy and the robustness of survival prediction of outcome in ovarian cancer treatment. The study also revealed subnetwork signatures that are enriched by extracellular matrix receptors and modulators and the downstream nuclear signaling components of extracellular signal-regulators, respectively. In particular, FBN1, which was detected as a signature gene of high confidence by Net-Cox with network information, was validated as a biomarker for predicting early recurrence in platinum-sensitive ovarian cancer patients in laboratory.

Mammary analog secretory carcinoma of salivary glands: a report of 2 cases with expression of basal/myoepithelial markers (calponin, CD10 and p63 protein)

Mammary analog secretory carcinoma (MASC) of salivary glands is a recently described neoplasm with favorable outcome. We describe 2 cases of MASC occurring in a 34-year-old female and a 58-year-old male, both presenting with a swelling of upper lip and right parotid gland, measuring 15 and 20mm, respectively. Without adjuvant treatment, both patients have been free of disease for 15 months and 12 months since the operation. Microscopically, both tumors were cystic and showed tubular and cystopapillary architecture. The tumor cells had round to oval nuclei and eosinophilic cytoplasm. Presence of eosinophilic material was evident within cystic spaces. Immunohistochemically, both tumors expressed cytokeratins (CK), CK7, CK8, CK18, epithelial membrane antigen, vimentin, S-100 protein, mammaglobin, and STAT5a (signal transducer and activator of transcription 5a). Interestingly, both tumors showed variable expression of basal/myoepithelial markers. In one case, we observed diffuse expression of calponin and focal expression of p63 whereas expression of CD10 was absent. In the second case, the staining of calponin was negative, but there was focal expression of both p63 and CD10. Both neoplasms harbored the ETV6-NTRK3 fusion transcript as proved by RT-PCR. Although previously reported only rarely, we conclude that MASC may show expression of basal/myoepithelial markers.

Reduced podocin expression in minimal change disease and focal segmental glomerulosclerosis is related to the level of proteinuria

BACKGROUND

Glomerular podocyte molecules are involved in the pathogenesis of congenital nephrotic syndrome. However, their role in primary nephrotic syndrome is not clear. This study investigated the expression of nephrin, podocin and synaptopodin in primary nephrotic syndrome.

METHODS

Eighty-seven patients with primary nephrotic syndrome including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN) and membranoproliferative glomerulonephritis Type I (MPGN) were included in the study. Glomerular expression of nephrin, podocin and synaptopodin was studied in renal biopsies by immunofluorescence and immunohistochemistry. Correlation of expression with clinical and biochemical parameters was performed.

RESULTS

The pattern of expression for all podocyte proteins in controls was uniform fine granular along the capillary walls towards the visceral epithelial cell aspect. Glomerular expression of nephrin was present in all renal biopsies and was similar to that in controls. Glomerular synaptopodin expression was seen in all MN and MPGN patients, while it was seen in 74 % (17/23) MCD and 93.5 % (29/31) FSGS. Reduced synaptopodin expression showed no correlation with clinical and biochemical factors. Podocin expression was present in 5/23 MCD (22 %), 3/31 FSGS (9.6 %), 13/17 MN (76.4 %) and 13/16 MPGN (81 %) patients. The reduced expression of podocin significantly correlated with the degree of proteinuria (p = 0.032). No correlation with age, gender and serum creatinine level was observed.

CONCLUSION

Reduction of glomerular podocin expression found in MCD and FSGS is related to the amount of proteinuria. Our findings suggest that alteration in podocyte phenotype may not be a primary event and may reflect the degree of podocyte injury in primary nephrotic syndrome.

TIPE2 deficiency accelerates neointima formation by downregulating smooth muscle cell differentiation

Phenotypic switching of vascular smooth muscle cells (VSMCs) is known to play a key role in the development of atherosclerosis. However, the mechanisms that mediate VSMC phenotypic switching are unclear. We report here that TIPE2, the tumor necrosis factor (TNF) α-induced protein 8-like 2 (TNFAIP8L2), plays an atheroprotective role by regulating phenotypic switching of VSMCs in response to oxidized low-density lipoprotein (ox-LDL) stimuli. TIPE2-deficient VSMCs treated with ox-LDL expressed lower levels of contractile proteins such as SMαA, SM-MHC and calponin, whereas the proliferation, migration and the synthetic capacity for growth factors and cytokines were increased remarkably. Furthermore, TIPE2 inhibited VSMCs proliferation by preventing G 1/S phase transition. Interestingly, these effects of TIPE2 on VSMCs were dependent on P38 and ERK1/2 kinase signals. As a result, neointima formation was accelerated in the carotid arteries of TIPE2-deficient mice. These results indicate that TIPE2 is a potential inhibitor of atherosclerosis.

Moesin as a key cytoskeleton regulator in corneal fibrosis

PURPOSE

: Corneal fibrosis is the third leading cause of blindness worldwide. α-Smooth muscle actin (SMA), a marker of fibrosis, is closely regulated through an intermediate group of submembrane molecules - cytoskeleton regulators. The purpose of this study was to elucidate the role of specific cytoskeleton regulators in a mouse model of corneal fibrosis.

METHODS

: A mouse model of corneal fibrosis was developed using anterior keratectomy (AK) and the topical application of transforming growth factor (TGF)-β1 (1 μg/ml). The RT² Profiler™ PCR Array for cytoskeleton regulators was used to assay changes in levels of specific members of this class of proteins. Moesin siRNA was delivered into the corneal stroma by iontophoresis in vivo. Transformation of the corneal keratocyte-to-myofibroblast in corneal fibrosis, as defined by the expression of α-SMA, was determined by Western blot.

RESULTS

: After AK and topical application of TGF-β1, moesin was the most highly upregulated gene among 84 cytoskeleton regulator genes; iontophoresing moesin siRNA into the corneal stroma reduced the expression of α-SMA to 0.22-, 0.52-, and 0.31-fold of control at postoperative (PO) day 1, 3, and 5, respectively; also, upregulation of phospho-Smad 2 induced by TGF-β1 was reduced by moesin siRNA to 0.59-, 0.56-, and 0.31-fold of control and expression of phospho-Smad 3 was reduced to 0.58-, 0.53-, and 0.47-fold of control at the same PO days.

CONCLUSIONS

: Moesin may be a potential drug target for inhibiting corneal fibrosis, and the details of moesin-related signaling pathways would be critical for understanding corneal fibrosis.

Human endothelial progenitor cells induce extracellular signal-regulated kinase-dependent differentiation of mesenchymal stem cells into smooth muscle cells upon cocultivation

Neovascularization represents an important issue in tissue-engineering applications, since survival of implanted cells strongly relies on sufficient oxygen and nutrient supply. We have recently observed that human bone marrow-derived mesenchymal stem cells (MSCs) support neovessel formation originating from coimplanted endothelial cells (ECs) in vivo, suggesting that MSCs may function as perivascular cells by investing and stabilizing nascent EC-derived neovessels. In this study, we investigated EC-induced mural cell differentiation of MSCs in vitro. For this purpose, endothelial progenitor cells (EPCs) from two different origins, namely adult peripheral blood (pbEPCs) and neonatal cord blood (cbEPCs), or human umbilical vein endothelial cells (HUVECs), were cocultured with human MSCs to analyze the effect on MSC differentiation toward a smooth muscle cell (SMC)/pericyte phenotype. EPCs as well as HUVECs increased alpha-smooth muscle actin expression in MSCs upon cocultivation in a time-dependent manner. This effect was strongly dependent on direct cell-to-cell contact and extracellular signal-regulated kinase (ERK) signaling, but was not mediated by heterotypic gap junction communication. Beyond enhanced SMC marker gene expression in MSCs, EPCs also enhanced the functional characteristics of cocultured MSCs by increasing their ability to attach to EC tubes in vitro. In conclusion, our study has shown that EPCs from adult peripheral blood as well as from cord blood commit cocultivated MSCs toward an SMC/pericyte phenotype in a cell-contact- and ERK-dependent manner.

Focal adhesion kinase knockdown modulates the response of human corneal epithelial cells to topographic cues

A rapidly expanding literature broadly documents the impact of biophysical cues on cellular behaviors. In spite of increasing research efforts in this field, the underlying signaling processes are poorly understood. One of the candidate molecules for being involved in mechanotransduction is focal adhesion kinase (FAK). To examine the role of FAK in the response of immortalized human corneal epithelial (hTCEpi) cells to topographic cues, FAK was depleted by siRNA transfection. Contrary to expectations, FAK knockdown resulted in an enhanced response with a greater number of hTCEpi cells aligned to the long axis of anisotropically ordered surface ridges and grooves. Both underlying topographic features and FAK depletion modulated the migration of corneal epithelial cells. The impact of FAK knockdown on both migration and alignment varied depending on the topographic cues to which the cells were exposed, with the most significant change observed on the biologically relevant size scale (400nm). Additionally, a change in expression of genes encoding perinuclear Nesprins 1 and 2 (SYNE1, 2) was observed in response to topographic cues. SYNE1/2 expression was also altered by FAK depletion, suggesting that these proteins might represent a link between cytosolic and nuclear signaling processes. The data presented here have relevance to our understanding of the fundamental processes involved in corneal cell behavior to topographic cues. These results highlight the importance of incorporating biophysical cues in the conduction of in vitro studies and into the design and fabrication of implantable prosthetics.

Muscarinic receptor stimulation augments TGF-β1-induced contractile protein expression by airway smooth muscle cells

Acetylcholine (ACh) is the primary parasympathetic neurotransmitter in the airways. Recently, it was established that ACh, via muscarinic receptors, regulates airway remodeling in animal models of asthma and chronic obstructive pulmonary disease (COPD). The mechanisms involved are not well understood. Here, we investigated the functional interaction between muscarinic receptor stimulation and transforming growth factor (TGF)-β(1) on the expression of contractile proteins in human airway smooth muscle (ASM) cells. ASM cells expressing functional muscarinic M(2) and M(3) receptors were stimulated with methacholine (MCh), TGF-β(1), or their combination for up to 7 days. Western blot analysis revealed a strong induction of sm-α-actin and calponin by TGF-β(1), which was increased by MCh in ASM cells. Immunocytochemistry confirmed these results and revealed that the presence of MCh augmented the formation of sm-α-actin stress fibers by TGF-β(1). MCh did not augment TGF-β(1)-induced gene transcription of contractile phenotype markers. Rather, translational processes were involved in the augmentation of TGF-β(1)-induced contractile protein expression by muscarinic receptor stimulation, including phosphorylation of glycogen synthase kinase-3β and 4E-binding protein 1, which was enhanced by MCh. In conclusion, muscarinic receptor stimulation augments functional effects of TGF-β(1) in human ASM cells on cellular processes that underpin ASM remodeling in asthma and COPD.

Reversal of pulmonary vascular remodeling in pulmonary hypertensive rats

Pulmonary hypertension is responsible for significant mortality and morbidity among newborns and infants. The pathology is characterized by pulmonary vascular remodeling with medial hypertrophy and adventitial thickening, leading to decreased gas exchange. Since it is unknown if these abnormalities are reversible, we analyzed these vascular changes in pulmonary hypertensive rats. Exposure of rats to hypobaric hypoxia for 4 weeks induced clinical signs of pulmonary hypertension, such as increased right ventricular systolic pressure, increased right ventricular weight and considerable pulmonary vascular remodeling. The vascular changes were associated with the expression of Non -Muscle Myosin Heavy Chain B in the pre-acinar vessels and an increased expression of alpha Smooth Muscle Actin, Smooth Muscle Myosin Heavy Chain 2 and Calponin in the intra-acinar vessels. The right ventricular systolic pressure and right ventricular weight gradually decreased after specific periods of recovery in normoxia, although this reversal did not reach baseline levels after six weeks at normoxia. However, the cellular changes in the pulmonary vasculature were completely reversed. Development of pulmonary hypertension is associated with an increase of synthetic perivascular cells in the pre-acinar arteries and an aberrant differentiation of perivascular cells in the smallest intra-acinar arteries. These cellular and structural changes in the pulmonary vasculature are completely reversible after recovery in normoxia.

cGMP-dependent protein kinase Iα transfection inhibits hypoxia-induced migration, phenotype modulation and annexins A1 expression in human pulmonary artery smooth muscle cells

Our previous work has demonstrated that the cellular phenotype changes of human pulmonary artery smooth muscle cells (PASMCs) play an important role during pulmonary vascular remodelling. However, little is known about the role of PASMCs phenotype modulation in the course of hypoxia-induced migration and its behind molecular mechanisms. In this study, we have shown that cGMP-dependent protein kinase (PKG) Iα transfection significantly attenuated the hypoxia-induced down-regulation of the expressions of SM-α-actin, MHC and calponin. Hypoxia-induced PASMC migration was also suppressed by PKGIα overexpression. Furthermore, this overexpression attenuated ANX A1 upregulation under hypoxic conditions. All those effects were reversed by a PKG inhibitor KT5823. Our data indicate that manipulating upstream entity e.g., PKGIa, may have a potential therapeutic value to prevent hypoxia-associated pulmonary arterial remodeling for pulmonary hypertension development.