Assessment of the Cardiac Noncoding Transcriptome by Single-Cell RNA Sequencing Identifies FIXER, a Conserved Profibrogenic Long Noncoding RNA.

BACKGROUND: Cardiac fibroblasts have crucial roles in the heart. In particular, fibroblasts differentiate into myofibroblasts in the damaged myocardium, contributing to scar formation and interstitial fibrosis. Fibrosis is associated with heart dysfunction and failure. Myofibroblasts therefore represent attractive therapeutic targets. However, the lack of myofibroblast-specific markers has precluded the development of targeted therapies. In this context, most of the noncoding genome is transcribed into long noncoding RNAs (lncRNAs). A number of lncRNAs have pivotal functions in the cardiovascular system. lncRNAs are globally more cell-specific than protein-coding genes, supporting their importance as key determinants of cell identity. METHODS: In this study, we evaluated the value of the lncRNA transcriptome in very deep single-cell RNA sequencing. We profiled the lncRNA transcriptome in cardiac nonmyocyte cells after infarction and probed heterogeneity in the fibroblast and myofibroblast populations. In addition, we searched for subpopulation-specific markers that can constitute novel targets in therapy for heart disease. RESULTS: We demonstrated that cardiac cell identity can be defined by the sole expression of lncRNAs in single-cell experiments. In this analysis, we identified lncRNAs enriched in relevant myofibroblast subpopulations. Selecting 1 candidate we named FIXER (fibrogenic LOX-locus enhancer RNA), we showed that its silencing limits fibrosis and improves heart function after infarction. Mechanitically, FIXER interacts with CBX4, an E3 SUMO protein ligase and transcription factor, guiding CBX4 to the promoter of the transcription factor RUNX1 to control its expression and, consequently, the expression of a fibrogenic gene program.. FIXER is conserved in humans, supporting its translational value. CONCLUSIONS: Our results demonstrated that lncRNA expression is sufficient to identify the various cell types composing the mammalian heart. Focusing on cardiac fibroblasts and their derivatives, we identified lncRNAs uniquely expressed in myofibroblasts. In particular, the lncRNA FIXER represents a novel therapeutic target for cardiac fibrosis.

The Flt3-inhibitor quizartinib augments apoptosis and promotes maladaptive remodeling after myocardial infarction in mice.

BACKGROUND: Tyrosine kinase inhibitors (TKIs) targeting fms-like tyrosine kinase 3 (Flt3) such as quizartinib were specifically designed for acute myeloid leukemia treatment, but also multi-targeting TKIs applied to solid tumor patients inhibit Flt3. Flt3 is expressed in the heart and its activation is cytoprotective in myocardial infarction (MI) in mice. OBJECTIVES: We sought to test whether Flt3-targeting TKI treatment aggravates cardiac injury after MI. METHODS AND RESULTS: Compared to vehicle, quizartinib (10 mg/kg/day, gavage) did not alter cardiac dimensions or function in healthy mice after four weeks of therapy. Pretreated mice were randomly assigned to MI or sham surgery while receiving quizartinib or vehicle for one more week. Quizartinib did not aggravate the decline in ejection fraction, but significantly enhanced ventricular dilatation one week after infarction. In addition, apoptotic cell death was significantly increased in the myocardium of quizartinib-treated compared to vehicle-treated mice. In vitro, quizartinib dose-dependently decreased cell viability in neonatal rat ventricular myocytes and in H9c2 cells, and increased apoptosis as assessed in the latter. Together with H2O2, quizartinib potentiated the phosphorylation of the pro-apoptotic mitogen activated protein kinase p38 and augmented H2O2-induced cell death and apoptosis beyond additive degree. Pretreatment with a p38 inhibitor abolished apoptosis under quizartinib and H2O2. CONCLUSION: Quizartinib potentiates apoptosis and promotes maladaptive remodeling after MI in mice at least in part via a p38-dependent mechanism. These findings are consistent with the multi-hit hypothesis of cardiotoxicity and make cardiac monitoring in patients with ischemic heart disease under Flt3- or multi-targeting TKIs advisable.

Giant intradural extramedullary spinal ependymoma, a rare arachnoiditis-mimicking condition: case report and literature review.

BACKGROUND AND IMPORTANCE: Ependymomas are tumours arising from the ependymal cells lining the ventricles and the central canal of the spinal cord. They represent the most common intramedullary spinal cord tumour in adults and are very rarely encountered in an extramedullary location. Only 40 cases of intradural extramedullary (IDEM) ependymomas have been reported, all of which were diagnosed pre-operatively as IDEM ependymomas on contrast-enhanced MRI. CLINICAL PRESENTATION: We report a 23-year old male presenting with rapidly worsening signs and symptoms of spinal cord disease. A spinal MRI demonstrated a posterior multi-cystic dilatation extended between T1 and T12. Post-contrast sequences showed peri-medullar leptomeningeal enhancement and the diagnosis of spinal arachnoiditis was made. The patient underwent surgery and the spinal cord appeared circumferentially wrapped by an irregular soft tissue. The tissue was sub-totally removed and the pathological diagnosis was ependymoma WHO grade II. The patient experienced an excellent neurological recovery and no further treatments were administered. A small residue is now stable at 2.5 years follow-up. CONCLUSIONS: Giant IDEM ependymomas are rare entities and pre-operative diagnosis can be challenging in some cases. Surgery represents the main treatment option being resolutive in most cases.

Early Gastric Cancer: identification of molecular markers able to distinguish submucosa-penetrating lesions with different prognosis.

BACKGROUND: Early Gastric Cancer (EGC) reaches 25% of the gastric cancers surgically treated in some areas of Northeastern Italy and is usually characterized by a good prognosis. However, among EGCs classified according to Kodama's criteria, Pen A subgroup is characterized by extensive submucosal invasion, lymph node metastases and worse prognosis, whereas Pen B subgroup by better prognosis. The aim of the study was to characterize the differences between Pen A, Pen B and locally advanced gastric cancer (T3N0) in order to identify biomarkers involved in aggressiveness and clinical outcome. METHODS: We selected 33 Pen A, 34 Pen B and 20 T3N0 tumors and performed immunohistochemistry of mucins, copy number variation analysis of a gene panel, microsatellite instability (MSI), TP53 mutation and loss of heterozygosity (LOH) analyses. RESULTS: Pen A subgroup was characterized by MUC6 overexpression (p = 0.021). Otherwise, the Pen B subgroup was significantly associated with the amplification of GATA6 gene (p = 0.002). The higher percentage of MSI tumors was observed in T3N0 group (p = 0.002), but no significant differences between EGC types were found. Finally, TP53 gene analysis showed that 32.8% of Pen tumors have a mutation in exons 5-8 and 50.0% presented LOH. Co-occurrence of TP53 mutation and LOH mainly characterized Pen A tumors (p = 0.022). CONCLUSIONS: Our analyses revealed that clinico-pathological parameters, microsatellite status and frequency of TP53 mutations do not seem to distinguish Pen subgroups. Conversely, the amplification of GATA6 was associated with Pen B, as well as the overexpression of MUC6 and the TP53mut/LOH significantly characterized Pen A.

Autoadaptive ER-associated degradation defines a preemptive unfolded protein response pathway.

Folding-defective proteins must be cleared efficiently from the endoplasmic reticulum (ER) to prevent perturbation of the folding environment and to maintain cellular proteostasis. Misfolded proteins engage dislocation machineries (dislocons) built around E3 ubiquitin ligases that promote their transport across the ER membrane, their polyubiquitylation, and their proteasomal degradation. Here, we report on the intrinsic instability of the HRD1 dislocon and the constitutive, rapid turnover of the scaffold protein HERP. We show that HRD1 dislocon integrity relies on the presence of HRD1 clients that interrupt, in a dose-dependent manner, the UBC6e/RNF5/p97/proteasome-controlled relay that controls HERP turnover. We propose that ER-associated degradation (ERAD) deploys autoadaptive regulatory pathways, collectively defined as ERAD tuning, to rapidly adapt degradation activity to misfolded protein load and to preempt the unfolded protein response (UPR) activation.

Role of the SEL1L:LC3-I complex as an ERAD tuning receptor in the mammalian ER.

Several regulators of endoplasmic reticulum (ER)-associated degradation (ERAD) have a shorter half-life compared to conventional ER chaperones. At steady state, they are selectively removed from the ER by poorly defined events collectively referred to as ERAD tuning. Here we identify the complex comprising the type-I transmembrane protein SEL1L and the cytosolic protein LC3-I as an ERAD tuning receptor regulating the COPII-independent, vesicle-mediated removal of the lumenal ERAD regulators EDEM1 and OS-9 from the ER. Expression of folding-defective polypeptides enhances the lumenal content of EDEM1 and OS-9 by inhibiting their SEL1L:LC3-I-mediated segregation. This raises ERAD activity in the absence of UPR-induction. The mouse hepatitis virus (MHV) subverts ERAD tuning for replication. Consistently, SEL1L or LC3 silencing impair the MHV life cycle. Collectively, our data provide new molecular information about the ERAD tuning mechanisms that regulate ERAD in mammalian cells at the post translational level and how these mechanisms are hijacked by a pathogen.

Extra-axial anaplastic astroblastoma in a 67-year-old woman.

Astroblastoma is a rare glial neoplasia of the central nervous system. It is histologically defined by the presence of neoplastic cells with non- or slightly tapering processes arranged around blood vessels (astroblastic rosettes) and conventionally subdivided into well-differentiated and anaplastic. It commonly affects children and young adults, although cases and due to its superficial location in the brain cortex, it can mimic an extra-axial mass on magnetic resonance imagining. Herein, we describe a unique case of pure extra-axial anaplastic astroblastoma in an elderly woman. Awareness that astroblastoma may be also extra-axial and affect older subjects, may be helpful for its identification and differential diagnosis toward more common entities at this site and age of onset, and for appropriate therapeutic management as well.

How viruses hijack the ERAD tuning machinery.

An essential step during the intracellular life cycle of many positive-strand RNA viruses is the rearrangement of host cell membranes to generate membrane-bound replication platforms. For example, Nidovirales and Flaviviridae subvert the membrane of the endoplasmic reticulum (ER) for their replication. However, the absence of conventional ER and secretory pathway markers in virus-induced ER-derived membranes has for a long time hampered a thorough understanding of their biogenesis. Recent reports highlight the analogies between mouse hepatitis virus-, equine arteritis virus-, and Japanese encephalitis virus-induced replication platforms and ER-associated degradation (ERAD) tuning vesicles (or EDEMosomes) that display nonlipidated LC3 at their cytosolic face and segregate the ERAD factors EDEM1, OS-9, and SEL1L from the ER lumen. In this Gem, we briefly summarize the current knowledge on ERAD tuning pathways and how they might be hijacked for viral genome replication. As ERAD tuning components, such as SEL1L and nonlipidated LC3, appear to contribute to viral infection, these cellular pathways represent novel candidate drug targets to combat positive-strand RNA viruses.

N-glycan structures: recognition and processing in the ER.

The processing of N-linked glycans determines secretory protein homeostasis in the eukaryotic cell. Folding and degradation of glycoproteins in the endoplasmic reticulum (ER) are regulated by molecular chaperones and enzymes recruited by specific oligosaccharide structures. Recent findings have identified several components of this protein quality control system that specifically modify N-linked glycans, thereby generating oligosaccharide structures recognized by carbohydrate-binding proteins, lectins. In turn, lectins direct newly synthesized polypeptides to the folding, secretion or degradation pathways. The "glyco-code of the ER" displays the folding status of a multitude of cargo proteins. Deciphering this code will be instrumental in understanding protein homeostasis regulation in eukaryotic cells and for intervention because such processes can have crucial importance for clinical and industrial applications.

Non-coding RNAs and their potential exploitation in cancer therapy-related cardiotoxicity.

Life expectancy in cancer patients has been extended in recent years, thanks to major breakthroughs in therapeutic developments. However, this also unmasked an increased incidence of cardiovascular diseases in cancer survivors, which is in part attributable to cancer therapy-related cardiovascular toxicity. Non-coding RNAs (ncRNAs) have received much appreciation due to their impact on gene expression. NcRNAs, which include microRNAs, long ncRNAs and circular RNAs, are non-protein-coding transcripts that are involved in the regulation of various biological processes, hence shaping cell identity and behaviour. They have also been implicated in disease development, including cardiovascular diseases, cancer and, more recently, cancer therapy-associated cardiotoxicity. This review outlines key features of cancer therapy-associated cardiotoxicity, what is known about the roles of ncRNAs in these processes and how ncRNAs could be exploited as therapeutic targets for cardioprotection.

ERAD substrates: which way out?

Global folding of polypeptides entering the endoplasmic reticulum (ER) starts as soon as they emerge from the narrow Sec61 translocon. Attainment of the native structure can take from several minutes to hours, depending on the gene product. Until then, non-native folding intermediates must be protected from molecular chaperones that recognize misfolded determinants and could prematurely interrupt folding programs by re-directing them to disposal pathways. On the other hand, futile folding attempts must actively be stopped to prevent intraluminal accumulation of defective cargo. This review describes recent advances in understanding how terminally misfolded polypeptides are extracted from the folding environment and directed to specific dislocons within the ER membrane for transfer to the cytoplasm for proteasome-mediated degradation.

HLA-G expression in melanomas.

OBJECTIVE: Human leukocyte antigen G (HLA-G) is a non-classical HLA class I molecule involved in inducing tolerance at the feto-maternal interface and in escape of immune response by tumor cells. The aim of the study is to review the published literature on the expression of HLA-G in malignant melanomas and its clinicopathological and prognostic correlates. METHODS: A systematic search was carried out in electronic databases. Studies dealing with HLA-G expression in surgically-removed human samples were retrieved and analyzed. RESULTS: Of 1737 retrieved articles, 16 were included. The main themes regarded HLA-G expression in malignant melanocytic lesions, assessed by immunohistochemistry (IHC), soluble or molecular techniques, and its relationship with clinicopathological features, such as tumor thickness and malignant behavior. Overall significant HLA-G expression was found in 460/843 tumors (55%), and specifically in 251/556 melanomas (45%) evaluated with IHC, in 208/250 cases (83%) examined with soluble methods and in 13/23 melanoma lesions (57%) tested with polymerase chain reaction. Despite the correlation with parameters indicating an aggressive behavior, no studies demonstrated any prognostic value of HLA-G expression. Furthermore, uveal melanomas were constantly negative for this biomarker. CONCLUSION: Overall, published data indicate that while HLA-G is involved in the interactions between melanomas and the immune system, it is unlikely to be the only factor to play such a role, therefore making it difficult to designate it as a prognostically relevant molecule. Evidence further suggests that HLA-G is not implicated in the immunobiology of uveal melanomas.

Epithelial-mesenchymal transition in undifferentiated carcinoma of the pancreas with and without osteoclast-like giant cells.

Undifferentiated carcinoma (UC) and undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) are peculiar variants of pancreatic ductal adenocarcinoma (PDAC), characterized by hypercellularity and absence of glandular patterns. The inflammatory microenvironment is peculiar in UCOGC, since it is dominated by macrophages and osteoclast-like giant cells. However, from a molecular point of view, both UC and UCOGC are very similar to conventional PDAC, sharing alterations of the most common genetic drivers. Clinically, UC usually show a worse prognosis, whereas UCOGC may show a better prognosis if it is not associated with a PDAC component. To highlight potential biological differences between these entities, we investigated the role of the epithelial to mesenchymal transition (EMT) in UC and UCOGC. Specifically, we analyzed the immunohistochemical expression of three well-known EMT markers, namely Twist1, Snai2, and E-cadherin, in 16 cases of UCOGC and 10 cases of UC. We found that EMT is more frequently activated in UC (10/10 cases) than in UCOGC (8/16 cases; p = 0.05). Furthermore, in UCOGC, EMT was activated with a higher frequency in cases with an associated PDAC component. Snai2 was the most frequently and strongly expressed marker in both tumor types (10/10 UC, 8/16 UCOGC), and its expression was higher in UC than in UCOGC (mean immunohistochemical score: 4.8 in UC vs. 2.1 in UCOGC, p < 0.01). Our results shed new light on the biology of UC and UCOGC: EMT appeared as a more important process in UC, and Snai2 emerged as a central EMT effector in this setting.

Prostatic chronic inflammation and prostate cancer risk at baseline random biopsy: Analysis of predictors.

OBJECTIVE: To evaluate predictors of prostatic chronic inflammation (PCI) and prostate cancer (PCa) in patients undergoing transperineal baseline random prostatic needle biopsies (BNB). PATIENT AND METHODS: According to BNB outcomes, patients were divided into four groups: cases without PCI or PCa (Control group), cases with PCI only (PCI group), cases with PCa and PCI (PCa+PCI group) and cases with PCa only (PCa group). A multinomial logistic regression model was used to evaluate the association of clinical factors with BNB outcomes. Additionally, clinical factors associated with the risk of PCa in the overall population were investigated using a multivariable logistic regression model (univariate and multivariate analysis). RESULTS: Overall, 945 patients were evaluated and grouped as follows: Control group, 308 patients (32.6%); PCI group, 160 (16.9%); PCa+PCI group, 45 (4.8%); and PCa group, 432 (45.7%). Amongst these, PCa was independently predicted by age (odds ratio [OR] 1.081), prostate specific-antigen level (PSA; OR 1.159), transition zone volume (TZV; OR 0.916), and abnormal digital rectal examination (DRE; OR 1.962). PCa and PCI (4.8%) were independently predicted by age (OR 1.081), PSA level (OR 1.122) and TZV (OR 0.954). In the group without PCa, the PSA level was the only factor associated with the risk of PCI when compared to the control group (OR 1.051, P = 0.042). Among patients with PCa, independent factors associated with the risk of only PCa compared to cases with PCA+PCI were TZV (OR 0.972) and number of positive cores (OR 1.149). In the overall population, PCI was the strongest predictor of a decreased risk of PCa (multivariate model, OR 0.212; P < 0.001). CONCLUSIONS: At BNB, PCI was associated with both a decreased risk of PCa and less aggressive tumour biology amongst patients with PCa. The presence of PCI on biopsy cores should be reported because of its implications in clinical practice. ABBREVIATIONS: BGG: biopsy Gleason Group; BPC: biopsy positive (cancer) cores; BMI: body mass index; FGF-2: fibroblast growth factor 2; IL: interleukin; ISUP: International Society of Urologic Pathology; NIH: National Institutes of Health; OR: odds ratio; PCa: prostate cancer; PCI: prostatic chronic inflammation; TGF: transforming growth factor; TPV: total prostate volume; TZV: transition zone volume.

Linear extent of positive surgical margin impacts biochemical recurrence after robot-assisted radical prostatectomy in a high-volume center.

The objective of this study is to evaluate if surgeon volume and stratifying positive surgical margins (PSM) into focal and non-focal may differentially impact the risk of biochemical recurrence (BCR) after robot-assisted radical prostatectomy (RARP). Between January 2013 and December 2017, 732 consecutive patients were evaluated. The population included negative cases (control group) and PSM subjects (study group). PSMs were stratified as focal (≤ 1 mm) or non-focal (> 1 mm). A logistic regression model assessed the independent association of factors with the risk of PSM. The risk of BCR of PSM and other factors was assessed by Cox's multivariate proportional hazards. Overall, 192 (26.3%) patients had PSM focal in 133 patients; non-focal in 59 cases. Focal PSM was associated with the percentage of biopsy positive cores (BPC; OR 1.011; p = 0.015), extra-capsular extension (pT3a stage; OR 2.064; p = 0.016), seminal vesicle invasion (pT3b; OR 2.150; p = 0.010), body mass index (odds ratio, OR 0.914; p = 0.006), and high surgeon volume (OR 0.574; p = 0.006). BPC (OR 1.013; p = 0.044), pT3a (OR 4.832; p < 0.0001) and pT3b stage (OR 5.153; p = 0.001) were independent predictors of the risk of non-focal PSM. Surgeon volume was not a predictor of non-focal PSM (p = 0.224). Independent factors associated with the risk of BCR were baseline PSA (hazard ratio, HR 1.064; p = 0.004), BPC (HR 1.015; p = 0.027), ISUP biopsy grade group (BGG) 2/3 (HR 2.966; p 0.003) and BGG 4/5 (HR 3.122; p = 0.022) pathologic grade group 4/5 (HR 3.257; p = 0.001), pT3b (HR 2.900; p = 0.003), and non-focal PSM (HR 2.287; p = 0.012). Surgeon volume was not a predictor of BCR (p = 0.253). High surgeon volume is an independent factor that lowers the risk of focal PSM. Surgeon volume does not affect non-focal PSM and BCR. Negative as well as focal PSM are not associated with BCR.

Unusual presentation of primary aldosteronism with advanced target organ damage: A case report.

Patients with primary aldosteronism have greater cardiovascular morbidity and mortality than patients with primary hypertension and a comparable cardiovascular risk profile. Herein we present the case of a patient who developed multiple end-organ damage due to unrecognized and uncontrolled hypertension caused by an aldosterone-producing adrenal adenoma. Clinical and radiological evaluation revealed hypertensive encephalopathy, cardiomyopathy, retinopathy and nephropathy which required hemodialysis. Blood pressure control before surgery was difficult due to renal impairment that precluded the administration of anti-aldosterone drugs. Primary aldosteronism was cured by laparoscopic adrenalectomy and all antihypertensive drugs were suspended. A remarkable aspect of this case is the discordant results at screening test for primary aldosteronism: even though aldosterone-to-renin ratio is the most reliable method to identify possible cases of primary aldosteronism it can be misleading especially in case of multiple comorbidities and concomitant antihypertensive treatment. Furthermore, anti-aldosterone drugs are worrisome to use when renal damage is advanced but can be reconsidered when hemodialysis begins.

From fine-needle aspiration cytology to fluorescent in-situ hybridization in an unusual case of pharyngeal synovial sarcoma.

Synovial sarcoma arising in the pharynx is a rare entity, with very few cases described in literature, mainly as surgical-oriented case reports. We report the case of a healthy 20-year old man who presented with a painless right neck mass, clinically suspicious for a thyroid nodule. Ultrasound scan and fine-needle aspiration cytology failed to provide a definitive result, although suggesting a mesenchymal proliferation, in accordance with magnetic resonance imaging findings. Therefore, the lesion was removed with a minimally invasive surgical intervention. Definitive histologic and immunohistochemical examination of the surgical specimen revealed a biphasic synovial sarcoma, further validated by the detection of SS18 gene rearrangement on fluorescent in-situ hybridization examination. Although rarely, synovial sarcoma may arise in the pharynx. Radiological, cytological, histological and molecular findings are needed along each step of the diagnostic process.

High surgeon volume and positive surgical margins can predict the risk of biochemical recurrence after robot-assisted radical prostatectomy.

BACKGROUND: The aim of this study was to determine whether any clinical factors are independent predictors of positive surgical margins (PSM), and to assess the association of PSM and biochemical recurrence (BR) after robot-assisted radical prostatectomy (RARP). METHODS: The population included cases with negative surgical margins (control group) and patients with PSM (study group). Tumor grade was evaluated according to the International Society of Urologic Pathology (ISUP) system. A logistic regression model assessed the independent association of factors with the risk of PSM. The risk of BR was assessed by Cox's multivariate proportional hazards. RESULTS: A total of 732 consecutive patients were evaluated. Extend pelvic lymph node dissection (ePLND) was performed in 342 cases (46.7%). Overall, 192 cases (26.3%) had PSM. The risk of PSM was positively associated with the percentage of biopsy positive cores (BPC; odds ratio, OR = 1.012; p = 0.004), extracapsular extension (pT3a; OR=2.702; p < 0.0001), invasion of seminal vesicle (pT3b; OR = 2.889; p < 0.0001), but inversely with body mass index (OR = 0.936; p = 0.021), and high surgeon volume (OR = 0.607; p = 0.006). Independent clinical factors associated with the risk of BR were baseline prostate-specific antigen (PSA; hazard ratio, HR = 1.064; p = 0.004), BPC (HR = 1.015; p = 0.027), ISUP biopsy grade group (BGG) 2/3 (HR = 2.966; p = 0.003), and BGG 4/5 (HR = 3.122; p = 0.022). Pathologic factors associated with the risk of BR were ISUP group 4/5 (HR = 3.257; p = 0.001), pT3b (HR = 2.900; p = 0.003), and PSM (HR = 2.096; p = 0.045). CONCLUSIONS: In our cohort, features related to host, tumor, and surgeon volume are associated with the risk of PSM, which is also an independent parameter predicting BR after RARP. The surgical volume of the operating surgeon is an independent factor that decreases the risk of PSM, and, as such, the risk of BR.