98 research outputs found
Human Cutaneous Melanomas Lacking MITF and Melanocyte Differentiation Antigens Express a Functional Axl Receptor Kinase
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Differential expression of long non-coding RNAs are related to proliferation and histological diversity in follicular lymphomas
"This is the peer reviewed version of the following article: Roisman, Alejandro, et al. "Differential expression of long nonâcoding RNA s are related to proliferation and histological diversity in follicular lymphomas." British journal of haematology (2018), which has been published in final form at https://doi.org/10.1111/bjh.15656. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."Long non-coding RNAs (lncRNAs) comprise a family of non-coding transcripts that are emerging as relevant gene expression regulators of different processes, including tumour development. To determine the possible contribution of lncRNA to the pathogenesis of follicular lymphoma (FL) we performed RNA-sequencing at high depth sequencing in primary FL samples ranging from grade 1-3A to aggressive grade 3B variants using unpurified (n = 16) and purified (n = 12) tumour cell suspensions from nodal samples. FL grade 3B had a significantly higher number of differentially expressed lncRNAs (dif-lncRNAs) with potential target coding genes related to cell cycle regulation. Nine out of the 18 selected dif-lncRNAs were validated by quantitative real time polymerase chain reaction in an independent series (n = 43) of FL. RP4-694A7.2 was identified as the top deregulated lncRNA potentially involved in cell proliferation. RP4-694A7.2 silencing in the WSU-FSCCL FL cell line reduced cell proliferation due to a block in the G1/S phase. The relationship between RP4-694A7.2 and proliferation was confirmed in primary samples as its expression levels positively related to the Ki-67 proliferation index. In summary, lncRNAs are differentially expressed across the clinico-biological spectrum of FL and a subset of them, related to cell cycle, may participate in cell proliferation regulation in these tumours.Peer ReviewedPostprint (author's final draft
Transgene codon usage drives viral fitness and therapeutic efficacy in oncolytic adenoviruses.
Arming oncolytic adenoviruses with therapeutic transgenes is a well-established strategy for multimodal tumour attack. However, this strategy sometimes leads to unexpected attenuated viral replication and a loss of oncolytic effects, preventing these viruses from reaching the clinic. Previous work has shown that altering codon usage in viral genes can hamper viral fitness. Here, we have analysed how transgene codon usage impacts viral replication and oncolytic activity. We observe that, although transgenes with optimized codons show high expression levels at the first round of infection, they impair viral fitness and are therefore not expressed in a sustained manner. Conversely, transgenes encoded by suboptimal codons do not compromise viral replication and are thus stably expressed over time, allowing a greater oncolytic activity both in vitro and in vivo. Altogether, our work shows that fine-tuning codon usage leads to a concerted optimization of transgene expression and viral replication paving the way for the rational design of more efficacious oncolytic therapies
Effects of hypotensive and non-hypotensive doses of manidipine on structure, responses to endothelin-1 and ICAM-1 production in mesenteric small resistance arteries of spontaneously hypertensive rats.
We have evaluated the effects of a new calcium channel blocker, manidipine, given at both high, hypotensive and low, non-hypotensive doses, on vascular morphology, response to endothelin-1 and ICAM-1 production in mesenteric small resistance arteries of spontaneously hypertensive rats (SHR).Ten SHR were treated with manidipine 3 mg/kg per day (high dose) and 10 with manidipine 0.3 mg/kg/per day (low dose). The drug was administered by gavage from the 4th to 12th weeks of age. Eighteen Wistar-Kyoto (WKY) rats and 18 SHR were kept untreated as controls. Rats were killed at 13 weeks. Mesenteric small arteries were dissected and mounted on a micromyograph for determination of indexes of vascular structure (media thickness, wall thickness, media/lumen ratio).Systolic blood pressure was significantly reduced by the high dose of the drug, while no effect was observed with low-dose manidipine. A reduction in the media/lumen ratio was observed only in SHR treated with high-dose manidipine. The response to endothelin-1 in untreated SHR was significantly lower in comparison with WKY; a significant reduction was observed in SHR treated with high-dose manidipine. ICAM-1 vascular concentrations were higher in untreated SHR than in WKY controls. Both high- and low-dose manidipine reduced ICAM-1 concentrations toward normalization.Manidipine at high, hypotensive, but not at low, non-hypotensive doses has been proven to reduce structural alterations in mesenteric small resistance arteries, and to normalize vascular responses to endothelin-1. In addition, manidipine, at both low and high doses, may reduce ICAM-1 vascular production, thus suggesting a possible anti-atherogenic effect
Multivariate analysis of brain metabolism reveals chemotherapy effects on prefrontal cerebellar system when related to dorsal attention network
BACKGROUND: Functional brain changes induced by chemotherapy are still not well characterized. We used a novel approach with a multivariate technique to analyze brain resting state [(18)âF]FDG-PET in patients with lymphoma, to explore differences on cerebral metabolic glucose rate between chemotherapy-treated and non-treated patients. METHODS: PET/CT scan was performed on 28 patients, with 14 treated with systemic chemotherapy. We used a support vector machine (SVM) classification, extracting the mean metabolism from the metabolic patterns, or networks, that discriminate the two groups. We calculated the correct classifications of the two groups using the mean metabolic values extracted by the networks. RESULTS: The SVM classification analysis gave clear-cut patterns that discriminate the two groups. The first, hypometabolic network in chemotherapy patients, included mostly prefrontal cortex and cerebellar areas (central executive network, CEN, and salience network, SN); the second, which is equal between groups, included mostly parietal areas and the frontal eye field (dorsal attention network, DAN). The correct classification membership to chemotherapy or not chemotherapy-treated patients, using only one network, was of 50% to 68%; however, when all the networks were used together, it reached 80%. CONCLUSIONS: The evidenced networks were related to attention and executive functions, with CEN and SN more specialized in shifting, inhibition and monitoring, DAN in orienting attention. Only using DAN as a reference point, indicating the global frontal functioning before chemotherapy, we could better classify the subjects. The emerging concept consists in the importance of the investigation of brain intrinsic networks and their relations in chemotherapy cognitive induced changes
Investigating Neuroimaging Correlates of Early Frailty in Patients With Behavioral Variant Frontotemporal Dementia: A MRI and FDG-PET Study
Chemotherapy effects on brain glucose metabolism at rest
Background: A growing number of studies reports that chemotherapy may impair brain functions inducing cognitive changes which can persist in a subset of cancer survivors.
Aims: To investigate the neural basis of the chemotherapy-induced neurobehavioral changes by means of metabolic imaging and voxel-based statistical parametric mapping analyses.
Methods: We studied the resting brain [18]FDG-PET/CT images of 43 adult cancer patients with solid (n=12, 28%) or hematologic malignancies (n=31, 72%); 12 patients were studied prior to chemotherapy (No chemotherapy) while treated patients were divided into two matched subgroups: Early High (6 chemotherapy cycles, n=10), and Late Low (>9 months after chemotherapy, <6 chemotherapy cycles, n=21).
Findings: Compared to No chemotherapy, the Early High subgroup showed a significant bilateral (p<0.05) lower regional cerebral metabolic rate of glucose metabolism in both the prefrontal cortices and white matter, cerebellum, posterior medial cortices and limbic regions. A similar pattern emerged in the Early High versus Low Late comparison, while no significant result was obtained in the Low Late versus No chemotherapy comparison. The number of cycles and the post-chemotherapy time were negatively and positively correlated, respectively, with a set of these same brain regions.
Interpretation: The present study shows that chemotherapy induces significant transient changes in the glucose metabolism of multiple cerebral cortical and white matter regions with a prevailing involvement of the prefrontal cortex. The severity of these changes are significantly related with the number of chemotherapy cycles and a subset of brain regions seems to present longer lasting, but more subtle, metabolic changes
Cyclin D1 overexpression induces global transcriptional downregulation in lymphoid neosplasms
Cyclin D1 is an oncogene frequently overexpressed in human cancers that has a dual function as cell cycle and transcriptional regulator, although the latter is widely unexplored. Here, we investigated the transcriptional role of cyclin D1 in lymphoid tumor cells with cyclin D1 oncogenic overexpression. Cyclin D1 showed widespread binding to the promoters of most actively transcribed genes, and the promoter occupancy positively correlated with the transcriptional output of targeted genes. Despite this association, the overexpression of cyclin D1 in lymphoid cells led to a global transcriptional downmodulation that was proportional to cyclin D1 levels. This cyclin D1-dependent global transcriptional downregulation was associated with a reduced nascent transcription and an accumulation of promoter-proximal paused RNA polymerase II (Pol II) that colocalized with cyclin D1. Concordantly, cyclin D1 overexpression promoted an increase in the Poll II pausing index. This transcriptional impairment seems to be mediated by the interaction of cyclin D1 with the transcription machinery. In addition, cyclin D1 overexpression sensitized cells to transcription inhibitors, revealing a synthetic lethality interaction that was also observed in primary mantle cell lymphoma cases. This finding of global transcriptional dysregulation expands the known functions of oncogenic cyclin D1 and suggests the therapeutic potential of targeting the transcriptional machinery in cyclin D1-overexpressing tumors
Androgen receptor and its splicing variant 7 expression in peripheral blood mononuclear cells and in circulating tumor cells in metastatic castration-resistant prostate cancer
Androgen receptor (AR) signaling remains crucial in castration-resistant prostate cancer (CRPC). Since it is also essential in immune cells, we studied whether the expression of AR full-length (ARFL) and its splicing variant ARV7 in peripheral blood mononuclear cells (PBMC) predicts systemic treatment response in mCRPC in comparison with circulating-tumor cells (CTC). We measured ARFL and ARV7 mRNA in PBMC and CTC from patients prior to receiving abiraterone (AA), enzalutamide (E), or taxanes by a pre-amplification plus quantitative reverse-transcription PCR. They were also tested in LNCaP-ARV7-transfected and in 22RV1 docetaxel-resistant (22RV1DR) cells. We studied 171 PBMC from 136 patients and from 24 non-cancer controls, and 47 CTC from 22 patients. High PBMC ARV7 levels correlated with worse AA/E and better taxane response. In taxane-treated patients high PBMC ARFL also correlated with longer progression-free survival (PFS). High ARV7 and ARFL expression were independently associated with better biochemical-PFS. Conversely, high CTC ARV7 and ARFL correlated with shorter radiological-PFS and overall survival, respectively. High ARV7 in 22RV1DR and LNCaP-ARV7 cells correlated with taxane resistance. In conclusion, ARFL and ARV7 at PBMC or CTC have a different predictive role in the taxane response, suggesting a potential influence of the AR pathway from PBMC in such response modulation
Spermatozoa from infertile patients exhibit differences of DNA methylation associated with spermatogenesis-related processes: an array-based analysis
The influence of aberrant sperm DNA methylation on the reproductive capacity of couples has been postulated as a cause of infertility. This study compared the DNA methylation of spermatozoa of 19 fertile donors and 42 infertile patients using the Illumina 450K array. Clustering analysis of methylation data arranged fertile and infertile patients into two groups. Bivariate clustering analysis identified a differential distribution of samples according to the characteristics of seminogram and age, suggesting a possible link between these parameters and specific methylation profiles. The study identified 696 differentially methylated cytosine-guanine dinucleotides (CpG) associated with 501 genes between fertile donors and infertile patients. Ontological enrichment analysis revealed 13 processes related to spermatogenesis. Data filtering identified a set of 17 differentially methylated genes, some of which had functions relating to spermatogenesis. A significant association was identified between RPS6KA2 hypermethylation and advanced age (P = 0.016); APCS hypermethylation and oligozoospermia (P = 0.041); JAM3/NCAPD3 hypermethylation and numerical chromosome sperm anomalies (P = 0.048); and ANK2 hypermethylation and lower pregnancy rate (P = 0.040). This description of a set of differentially methylated genes provides a framework for further investigation into the influence of such variation in male fertility in larger patient cohorts.This work was supported by Projects PS09/00330 (Gobierno de España, Spain) and SGR2014-524 2 (Generalitat de Catalunya).Peer reviewe
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