miR-143 expression profiles in urinary bladder cancer: correlation with clinical and epidemiological parameters.

Hsa-mir-143 and hsa-let-7c have been reported to be deregulated in multiple neoplasms. The main purpose of this study was to investigate the expression of these miRNAs in bladder cancer (BCa) and to analyze the association between their expression profiles and clinical and epidemiological parameters. Ninety BCa specimens were included. Expression patterns of miR-143 and let-7c were assessed by qRT-PCR using Taqman specific probes. Validated and predicted targets of these miRNA's were identified using CSmiRTar and DAVID tools, respectively. miR-143 was downregulated in tumors compared to controls (mean fold-change (FC) = 0.076). Its expression was significantly higher in MIBC compared to NMIBC (p = 0,001). Its value as a potential biomarker discriminating non invasive tumors from the invasive ones was confirmed by ROC curve (AUC = 0.768; p = 0.0001). Also, this down-regulation positively correlates with frequency of tobacco use (p = 0,04) and chronic alcohol consumption (p = 0,04). Let-7c was overexpressed in BCa samples (mean (FC = 9.92) compared to non tumoral ones but was not associated to clinical and epidemiological parameters. A comprehensive overview of miR-143 targets and pathways implicated in BCa initiation, diagnosis or prognosis using bioinformatical analysis, was conducted. While both deregulated miRNAs may contribute to urothelial tumorigenesis, the deregulation of miR-143 was significantly correlated to epidemiological and clinical parameters.

Transcriptional activation of the miR-17-92 cluster is involved in the growth-promoting effects of MYB in human Ph-positive leukemia cells.

MicroRNAs, non-coding regulators of gene expression, are likely to function as important downstream effectors of many transcription factors including MYB. Optimal levels of MYB are required for transformation/maintenance of BCR-ABL-expressing cells. We investigated whether MYB silencing modulates microRNA expression in Philadelphia-positive (Ph+) leukemia cells and if MYB-regulated microRNAs are important for the "MYB addiction" of these cells. Thirty-five microRNAs were modulated by MYB silencing in lymphoid and erythromyeloid chronic myeloid leukemia-blast crisis BV173 and K562 cells; 15 of these were concordantly modulated in both lines. We focused on the miR-17-92 cluster because of its oncogenic role in tumors and found that: i) it is a direct MYB target; ii) it partially rescued the impaired proliferation and enhanced apoptosis of MYB-silenced BV173 cells. Moreover, we identified FRZB, a Wnt/ß-catenin pathway inhibitor, as a novel target of the miR-17-92 cluster. High expression of MYB in blast cells from 2 Ph+leukemia patients correlated positively with the miR-17-92 cluster and inversely with FRZB. This expression pattern was also observed in a microarray dataset of 122 Ph+acute lymphoblastic leukemias. In vivo experiments in NOD scid gamma mice injected with BV173 cells confirmed that FRZB functions as a Wnt/ß-catenin inhibitor even as they failed to demonstrate that this pathway is important for BV173-dependent leukemogenesis. These studies illustrate the global effects of MYB expression on the microRNAs profile of Ph+cells and supports the concept that the "MYB addiction" of these cells is, in part, caused by modulation of microRNA-regulated pathways affecting cell proliferation and survival.

The Protective Effect of Apocynin on Cyclosporine A-Induced Hypertension and Nephrotoxicity in Rats.

Cyclosporine A (CsA) is the prototype of immunosuppressant drugs that has provided new perspectives in human and veterinary medicine to prevent organ transplant rejection and to treat certain autoimmune diseases and dermatologic diseases. Unfortunately, the treatment with CSA is often limited by severe adverse effects such as hypertension and nephrotoxicity. Some data suggest that reactive oxygen species (ROS) and the oxidative stress play an important role in its pathogenesis, in particular the superoxide (O2 (-)) that is the most powerful free radical generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase present mainly in the kidney. The present study has been designed to investigate the role of Apocynin a selective inhibitor of NADPH oxidase activity on cyclosporine-induced adverse effect. In this study, we have evaluated the effect of CsA, used alone or in association with Apocynin on blood pressure (BP), on glomerular filtration rate (GFR), on absoluted fluid reabsorption (Jv) in proximal tubule (PT), on O2 (-) concentration, and on nitric oxide (NO) production. We have demonstrated that CsA administration increases superoxide concentration in the aorta, decreases the NO concentration, reduces GFR and the Jv in PT, and induces a significant increase in BP. Moreover, we have shown that Apocynin treatment restores these hemodynamic alterations, as well as NO and superoxide productions. In conclusion, the reported data indicate that CsA induced nephrotoxicity and hypertension are related to NADPH oxidase activity, in fact Apocynin protects the kidney function and BP from toxic effects induced by CsA through the inhibition of NADPH oxidase activity.

A new recombinant MnSOD prevents the cyclosporine A-induced renal impairment.

BACKGROUND: Cyclosporine A (CsA) is one of the most frequently used anticalcineurinic drugs for preventing graft rejection and autoimmune disease. Its use is hampered by nephrotoxic effects, namely an impairment of the glomerular filtration rate (GFR) and hypertension. Evidence suggests that reactive oxygen species (ROS) play a causal role in the nephrotoxicity. The present study aims to investigate in vivo the effects of a new recombinant mitochondrial manganese-containing superoxide dismutase (rMnSOD), a strong antioxidant, on the CsA-induced nephotoxicity. METHODS: Rats were treated with CsA (25 mg/kg/day) alone or in combination with rMnSOD (10 µg/kg/day) for 7 days. At the end of the treatment, GFR was estimated by inulin clearance (mL/min/100 g b.w.) and the mean arterial pressure (MAP) was recorded through a catheter inserted in the carotid artery. Superoxide concentration within the cells of the abdominal aorta was quantified from the oxidation of dihydroethidium (DHE). In kidney tissues, ROS levels were measured by the 2'7' dichloroflurescin diacetate assay. Renal morphology was examined at the histochemistry level. RESULTS: CsA-treated rats showed a severe decrease in GFR (0.34 ± 0.17 versus 0.94 ± 0.10 in control, P < 0.001) which was prevented by rMnSOD co-administration (0.77 ± 0.10). CsA-injected animals presented with higher blood pressure which was unaffected by rMnSOD. ROS levels both in the aorta and in renal tissue were significantly increased by CsA treatment, and normalized by the co-administration with rMnSOD. This effect was, partly, paralleled by the recovery from CsA-induced morphological lesions. CONCLUSIONS: Administration of rMnSOD prevents CsA-mediated impairment of the GFR along with morphological alteration. This effect could be related to the inhibition of ROS.

Delayed Lysis Time at High Multiplicities of Particles in a Chlorovirus-Chlorella Interaction.

When viruses infect microbial cells, their phenotypes depend on the host's genotype and on the environmental conditions. Here we describe such an effect in laboratory strains of the chlorovirus PBCV-1 and its algal host Chlorella variabilis. We studied the growth of six virus isolates, and found that the mean lysis time was 1.34±0.05 times longer at multiplicity of particles (MOP) 10 than at MOP 1. We could not detect any associated changes in burst size. This is a novel plastic trait for chloroviruses, and we hypothesize that it is caused by our specific laboratory algae.

Kronos scRT: a uniform framework for single-cell replication timing analysis.

Mammalian genomes are replicated in a cell type-specific order and in coordination with transcription and chromatin organization. Currently, single-cell replication studies require individual processing of sorted cells, yielding a limited number (<100) of cells. Here, we develop Kronos scRT, a software for single-cell Replication Timing (scRT) analysis. Kronos scRT does not require a specific platform or cell sorting, which allows investigating large datasets obtained from asynchronous cells. By applying our tool to published data as well as droplet-based single-cell whole-genome sequencing data generated in this study, we exploit scRT from thousands of cells for different mouse and human cell lines. Our results demonstrate that although genomic regions are frequently replicated around their population average RT, replication can occur stochastically throughout S phase. Altogether, Kronos scRT allows fast and comprehensive investigations of the RT programme at the single-cell resolution for both homogeneous and heterogeneous cell populations.

Diffuse large B-cell lymphoma: Time to focus on circulating blood nucleic acids?

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous neoplasm with diverse genetic abnormalities and outcomes. To date, DLBCL is invasively diagnosed by tissue biopsy and few biomarkers are available to predict patient outcome, treatment response and progression. The identification of patient-specific biomarkers would allow a "personalized medicine" approach for DLBCL patients. In this regard, "liquid biopsies" hold great promise, capturing the entire genetic landscape of the tumour and allowing a rapid and dynamic management of cancer. Liquid biopsy studies particularly focus on cell-free nucleic acids, such as cell-free DNA (cfDNA) and microRNAs, which are easy to collect and analyse. In accordance with the PRISMA criteria, we performed a systematic review on circulating nucleic acids as potential biomarkers for DLBCL management. The results suggest that combining information from the genetic (cfDNA) and epigenetic (microRNAs) landscape of the disease could lead to developing an integrated network of non-invasive biomarkers for the better management of DLBCL.

Potassium depletion induces cellular conversion in the outer medullary collecting duct altering Notch signaling pathway.

Potassium depletion affects AQP2 expression and the cellular composition of the kidney collecting duct. This, in turn, contributes to the development of a secondary form of nephrogenic diabetes insipidus and hypokalemic nephropathy. Here we show that after 14 days of potassium depletion, the cellular fraction of A-type intercalated cells increases while the fraction of principal cells decreases along the outer medullary collecting duct in rats. The intercalated cells acquired a novel distribution pattern forming rows of cells attached to each other. These morphological changes occur progressively and reverse after 7 days of recovery on normal rat chow diet. The cellular remodeling mainly occurred in the inner stripe of outer medulla similar to the previously seen effect of lithium on the collecting duct cellular profile. The cellular remodeling is associated with the appearance of cells double labelled with both specific markers of principal and type-A intercalated cells. The appearance of this cell type was associated with the downregulation of the Notch signaling via the Hes1 pathways. These results show that the epithelium of the collecting duct has a high degree of plasticity and that Notch signaling likely plays a key role during hypokalemia.

Urinary expression of let-7c cluster as non-invasive tool to assess the risk of disease progression in patients with high grade non-muscle invasive bladder Cancer: a pilot study.

BACKGROUND: High grade non-muscle-invasive bladder cancer (HG-NMIBC) is a heterogeneous disease with variable risk of progression. Urinary microRNAs are promising biomarkers for BC detection and surveillance. Let-7c-5p miRNA, clustered with miR-99a-5p and -125b-5p, is deregulated in cancer, including BC. The aim of this study is to evaluate urinary let-7c cluster expression in Ta/T1 HG-NMIBC patients and its impact on progression-free survival (PFS). METHODS: Quantitative Real-Time-Polymerase-Chain-Reaction (qRT-PCR) was used to analyze the let-7c cluster expression in 57 urine and 49 neoplastic paired tissue samples prospectively collected from transurethral resection (TUR) HG-NMIBC patients. Twenty urine and 10 bladder tissue samples were collected and analyzed as normal controls. QRT-PCR was also used to detect intra-/extra-cellular let-7c cluster in BC cells. Receiver Operating Characteristic (ROC) curves were used to identify urinary miRNAs cut-off values predicting T-stage and PFS. Uni/multivariable Cox regression was performed to identify predictors of PFS. A nomogram predicting progression risk and a decision curve analysis (DCA) were performed. RESULTS: Urinary let-7c was significantly up-regulated in patients compared with controls, while the whole cluster was down-regulated in tumor tissues. Supporting these findings, in vitro comparison of extra-/intra-cellular ratios of cluster levels between BC cells, showed a higher ratio for let-7c in HG-NMIBC versus low-grade cells. Urinary let-7c cluster expression was increased in higher T-stage and was an independent predictor of progression. Lower EORTC-score and downregulation of urinary cluster were predictors of higher PFS on univariable Cox regression, while on multivariable analysis only cluster expression was an independent progression predictor. On DCA, a benefit was evident for patients with a PFS probability > 20%. CONCLUSIONS: Urinary let-7c cluster evaluation may improve prognosis, identifying patients at risk of progression and addressing early radical treatment.

Serum miR-22 as potential non-invasive predictor of poor clinical outcome in newly diagnosed, uniformly treated patients with diffuse large B-cell lymphoma: an explorative pilot study.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous group of tumors, with aggressive clinical course that renders prognostication and choice of treatment strategy difficult. Chemo-immunotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP) is the current first-line treatment. MicroRNAs (miRNAs) are under investigation as novel diagnostic and prognostic biomarkers in several malignancies, including malignant lymphomas. While tissue miRNAs in DLBCL patients have been extensively studied as biomarkers, only few reports to date have evaluated the role of circulating/serum miRNAs as potential prognostic factors. Here circulating/serum miRNAs, including miR-22, were investigated as potential non-invasive biomarkers, with the aim of a better prognostic stratification of DLBCL patients. METHODS: MiRNAs were selected by global expression profile of serum miRNAs of DLBCL patients, The Cancer Genome Atlas (TCGA) analysis and literature research. Serum and tissues miRNA expression profile in de novo DLBCL patients, consecutively enrolled for this study, were detected by quantitative real-time polymerase chain reaction. Relative expression was calculated using the comparative Ct method. Statistical significance was determined using the Mann-Whitney rank sum and Fisher's exact test. Survival analysis was conducted through the use of Kaplan-Meier method. Spearman's Rho was applied to study the correlation between miRNA distributions and days to first relapse. Experimentally validated miRNA-target interactions were assessed by miRTarBase database. Negative miRNA-mRNA correlation was evaluated in TCGA DLBCL dataset. Pathway analysis was performed by the functional annotation clustering DAVID tool. RESULTS: We showed a significant modulation of serum miR-22 after R-CHOP treatment compared with basal values but no difference between baseline serum miRNAs values of DLBCL patients and healthy controls. High expression level of serum miR-22 in DLBCL at diagnosis (n = 36) is associated with a worse PFS and is independent of the currently used clinical prognostic index. Integrative and pathways analysis of miR-22 identified target genes involved in different important pathways such as p53 signaling. CONCLUSIONS: Our data suggest that miR-22 is of potential interest as non-invasive biomarker to predict clinical outcome in DLBCL patients. Characterization of miR-22 pathways can pave the way to the development of targeted therapy approaches for specific subgroups of DLBCL patients.

Semaphorin 5A drives melanoma progression: role of Bcl-2, miR-204 and c-Myb.

BACKGROUND: Melanoma, the most aggressive form of skin cancer, is characterized by high rates of metastasis, drug resistance and mortality. Here we investigated the role of Semaphorin 5A (Sema5A) on the properties associated with melanoma progression and the factors involved in Sema5A regulation. METHODS: Western blotting, qRT-PCR, Chromatin immunoprecipitation (ChIP) assay, immunohistochemistry of melanoma patient specimens and xenograft tissues, in vitro Transwell assay for cell migration and invasion evaluation, in vitro capillary-like structure formation analysis. RESULTS: A significant correlation of Sema5A mRNA expression and melanoma progression was observed by analyzing GEO profile dataset. Endogenous Sema5A protein was detected in 95% of human melanoma cell lines tested, in 70% of metastatic specimens from patients affected by melanoma, and 16% of in situ melanoma specimens showed a focal positivity. We demonstrated that Sema5A regulates in vitro cell migration and invasion and the formation of vasculogenic structures. We also found an increase of Sema5A at both mRNA and protein level after forced expression of Bcl-2. By use of transcriptional and proteasome inhibitors, we showed that Bcl-2 increases the stability of Sema5A mRNA and protein. Moreover, by ChIP we demonstrated that Sema5A expression is under the control of the transcription factor c-Myb and that c-Myb recruitment on Sema5A promoter is increased after Bcl-2 overexpression. Finally, a concomitant decrease in the expression of Sema5A, Bcl-2 and c-Myb proteins was observed in melanoma cells after miR-204 overexpression. CONCLUSION: Overall our data provide evidences supporting the role of Sema5A in melanoma progression and the involvement of Bcl-2, miR-204 and c-Myb in regulating its expression.

The laminA/NF-Y protein complex reveals an unknown transcriptional mechanism on cell proliferation.

Lamin A is a component of the nuclear matrix that also controls proliferation by largely unknown mechanisms. NF-Y is a ubiquitous protein involved in cell proliferation composed of three subunits (-YA -YB -YC) all required for the DNA binding and transactivation activity. To get clues on new NF-Y partner(s) we performed a mass spectrometry screening of proteins that co-precipitate with the regulatory subunit of the complex, NF-YA. By this screening we identified lamin A as a novel putative NF-Y interactor. Co-immunoprecipitation experiments and confocal analysis confirmed the interaction between the two endogenous proteins. Interestingly, this association occurs on euchromatin regions, too. ChIP experiments demonstrate lamin A enrichment in several promoter regions of cell cycle related genes in a NF-Y dependent manner. Gain and loss of function experiments reveal that lamin A counteracts NF-Y transcriptional activity. Taking advantage of a recently generated transgenic reporter mouse, called MITO-Luc, in which an NF-Y-dependent promoter controls luciferase expression, we demonstrate that lamin A counteracts NF-Y transcriptional activity not only in culture cells but also in living animals. Altogether, our data demonstrate the occurrence of lamin A/NF-Y interaction and suggest a possible role of this protein complex in regulation of NF-Y function in cell proliferation.

A restricted signature of serum miRNAs distinguishes glioblastoma from lower grade gliomas.

BACKGROUND: Malignant gliomas are the most common primary brain tumors in adults and challenging cancers for diagnosis and treatment. They remain a disease for which non-invasive, diagnostic and/or prognostic novel biomarkers are highly desirable. Altered microRNA (miRNA) profiles have been observed in tumor tissues and biological fluids. To date only a small set of circulating/serum miRNA is found to be differentially expressed in brain tumors compared to normal controls. Here a restricted signature of circulating/serum miRNA including miR-15b*,-23a, -99a, -125b, -133a, -150*, -197, -340, -497, -548b-5p and let-7c were investigated as potential non-invasive biomarkers in the diagnosis of glioma patients. METHODS: Serum and tissues miRNAs expression in patients with brain cancers (n = 30) and healthy controls (n = 15) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Relative expression was calculated using the comparative Ct method. Statistical significance (p ≤ 0,05) was determined using the Mann-Whitney rank sum and Fisher's exact test. Diagnostic accuracy of miRNAs in distinguishing glioblastoma multiforme (GBM) from lower grade cancer was assessed by the Receiver Operating Characteristic (ROC) curve analysis. To validate the role of the identified miRNAs in cancer a comprehensive literature search was conducted using PubMed, Web of Science (Core Collection) and Scopus databases. RESULTS: We observed a decrease of miR-497 and miR-125b serum levels depending on tumor stages with reduced level in GBM than lower grade tumors. The ROC curve analysis distinguishing GBM from lower grade cases yielded an area under the curve (AUC) of 0.87 (95 % confidence interval (CI) = 0.712-1) and of 0.75 (95 % CI = 0.533-0.967) for miR-497 and -125b, respectively. GBM patients are more likely to show a miR-497 and -125b down-regulation than the lower grade group (p = 0.002 and p = 0.024, respectively). These results were subsequently compared with evidence from 19 studies included in the final systematic review. CONCLUSIONS: Although multiple biomarkers are currently leveraged in the clinic to detect specific cancer types, no such standard blood biomolecules are used as yet in gliomas. Our data suggest that serum miR-497 and -125b could be a novel diagnostic markers with good perspectives for future clinical applications in patients with glioma.

Selective dicer suppression in the kidney alters GSK3ß/ß-catenin pathways promoting a glomerulocystic disease.

Dicer is a crucial enzyme for the maturation of miRNAs. Mutations in the Dicer gene are highly associated with Pleuro Pulmonary Blastoma-Family Dysplasia Syndrome (PPB-FDS, OMIM 601200), recently proposed to be renamed Dicer syndrome. Aside from the pulmonary phenotype (blastoma), renal nephroma and thyroid goiter are frequently part of Dicer syndrome. To investigate the renal phenotype, conditional knockout (cKO) mice for Dicer in Pax8 expressing cells were generated. Dicer cKO mice progressively develop a glomerulocystic phenotype coupled with urinary concentration impairment, proteinuria and severe renal failure. Higher cellular turnover of the parietal cells of Bowman's capsule precedes the development of the cysts and the primary cilium progressively disappears with cyst-enlargement. Upregulation of GSK3ß precedes the development of the glomerulocystic phenotype. Downregulation of ß-catenin in the renal cortex and its cytosolic removal in the cells lining the cysts may be associated with observed accumulation of GSK3ß. Alterations of ß-catenin regulating pathways could promote cystic degeneration as in other models. Thus, miRNAs are fundamental in preserving renal morphology and function. Alteration of the GSK3ß/ß-catenin pathway could be a crucial mechanism linking miRNA dysregulation and the development of a glomerulocystic disease.