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Mucosal microbiota differ significantly from fecal microbiota and may play a different role in the pathophysiology of irritable bowel syndrome (IBS). The aims of this study were to determine if the composition of mucosal microbiota differed between IBS, or IBS bowel habit (BH) subtypes, and healthy controls (HCs). Sigmoid colon mucosal biopsies were obtained from 97 Rome-positive patients with IBS (28% IBS-constipation, 38% IBS-diarrhea, 24% IBS-mixed, and 10% IBS-unsubtyped) and 54 HCs, from which DNA was extracted. 16S rRNA gene sequencing and microbial composition analysis were performed. Group differences in α or β diversity and taxonomic level differences were determined using linear regression while controlling for confounding variables. IBS BH subtype was associated with microbial a diversity (P = 0.0003) with significant differences seen in the mucosal microbiota of IBS-constipation versus IBS-diarrhea (P = 0.046). There were no significant differences in α or β diversity in the mucosal microbiota of IBS versus HCs (P = 0.29 and 0.93, respectively), but metagenomic profiling suggested functional differences. The relative abundance of Prevotella_9 copri within IBS was significantly correlated with increased abdominal pain (r = 0.36, P = 0.0003), which has not been previously reported in IBS. Significant differences in the mucosal microbiota were present within IBS BH subtypes but not between IBS and HCs, supporting the possibility of IBS BH subtype-specific pathogenesis. Increased Prevotella copri may contribute to symptoms in patients with IBS. [ABSTRACT FROM AUTHOR]

Peripheral factors likely play a role in at least a subset of irritable bowel syndrome (IBS) patients. Few studies have investigated mucosal gene expression using an unbiased approach. Here, we performed mucosal gene profiling in a sex-balanced sample to identify relevant signaling pathways and gene networks and compare with publicly available profiling data from additional cohorts. Twenty Rome III+ IBS patients [10 IBS with constipation (IBS-C), 10 IBS with diarrhea (IBS-D), 5 men/women each), and 10 age-/sex-matched healthy controls (HCs)] underwent sigmoidoscopy with biopsy for gene microarray analysis, including differential expression, weighted gene coexpression network analysis (WGCNA), gene set enrichment analysis, and comparison with publicly available data. Expression levels of 67 genes were validated in an expanded cohort, including the above samples and 18 additional participants (6 each of IBS-C, IBS-D, HCs) using NanoString nCounter technology. There were 1,270 differentially expressed genes (FDR < 0.05) in IBS-C vs. HCs but none in IBS or IBS-D vs. HCs. WGNCA analysis identified activation of the cAMP/protein kinase A signaling pathway. Nine of 67 genes were validated by the NanoString nCounter technology (FDR < 0.05) in the expanded sample. Comparison with publicly available microarray data from the Mayo Clinic and University of Nottingham supports the reproducibility of 17 genes from the microarray analysis and three of nine genes validated by nCounter in IBS-C vs. HCs. This study supports the involvement of peripheral mechanisms in IBS-C, particularly pathways mediating neuronal signaling. [ABSTRACT FROM AUTHOR]

High-throughput technologies revealed new categories of genes, including the long noncoding RNAs (lncRNAs), involved in the pathogenesis of human disease; however, the role of lncRNAs in the ulcerative colitis (UC) has not been evaluated. Gene expression profiling was used to develop lncRNA signatures in UC samples. Jurkat T cells were activated by PMA/ ionomycin subsequently interferon-γ (IFNG) and tumor necrosis factor (TNF)-α protein levels were assessed by ELISA. Anti-sense molecules were designed to block IFNG-AS1 expression. A unique set of lncRNAs was differentially expressed between UC and control samples. Of these, IFNG-AS1 was among the highest statistically significant lncRNAs (fold change: 5.27, P value: 7.07E-06). Bioinformatic analysis showed that IFNG-AS1 was associated with the IBD susceptibility loci SNP rs7134599 and its genomic location is adjacent to the inflammatory cytokine IFNG. In mouse models of colitis, active colitis samples had increased colonic expression of this lncRNA. Utilizing the Jurkat T cell model, we found IFNG-AS1 to positively regulate IFNG expression. Novel lncRNA signatures differentiate UC patients with active disease, patients in remission, and control subjects. A subset of these lncRNAs was found to be associated with the clinically validated IBD susceptibility loci. IFNG-AS1 was one of these differentially expressed lncRNAs in UC patients and found to regulate the key inflammatory cytokine, IFNG, in CD4 T cells. Taking these findings together, our study revealed novel lncRNA signatures deregulated in UC and identified IFNG-AS1 as a novel regulator of IFNG inflammatory responses, suggesting the potential importance of noncoding RNA mechanisms on regulation of inflammatory bowel disease-related inflammatory responses. [ABSTRACT FROM AUTHOR]

Early onset dementia (EOD) is the dementia occurring before 65 years of age. Major causes of EOD are Alzheimer's disease (AD), vascular dementia (VaD) and fronto temporal dementia (FTD) along with some reversible causes. We aimed to know 1) Clinical characteristics of EOD 2) Pattern of first presentation 3) Role head injury, smoking and alcohol abuse 4) Impact on activities of daily living (ADL) 5) Complications like delirium and psychosis. We collected data after evaluation of cognitively impaired patients during 2011 to 2013. Interpretation was done by using frequency distribution. Out of 280 patients 50 were diagnosed as EOD (18%). Males were 43/50 (86%) and females were 7/50 (14%). AD was main cause of EOD (38%) followed by VaD (34%) and FTD (14%). About 42% presented with behavioral and 38% with memory symptoms as first presentation while 20% had both. Alcohol abuse and smoking was seen in 46% and 42% respectively. 14% patients showed positive family history of EOD and history of head injury. Psychosis was seen in 34% and delirium in 14% in the course of illness. VaD (76%) most commonly affected ADL followed by FTD (71%) and AD (68%). We concluded that 1) EOD was more prevalent in male. 2) FTD commonly presented with behavioral while AD with memory problems as first presentation. 3) Alcohol abuse and head injury predisposed to MxD while smoking to VaD. 4) VaD most severely affected ADL followed by FTD and AD. 5) Delirium was frequent VaD while psychosis in AD. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to test PENAO, a promising new organoarsenical that is in phase 1 testing in patients with solid tumours, on a range of ovarian cancer cell lines with different histotypes, and to understand the molecular basis of drug resistance exhibited by the endometrioid ovarian cancer cell line, SKOV-3. Methods Proliferation arrest and cell death induced by PENAO in serous (OVCAR-3), endometrioid (SKOV-3, TOV112D), clear cell (TOV21G) and mucinous (EFO27) ovarian cancer cells in culture, and anti-tumour efficacy in a murine model of SKOV-3 and OVCAR-3 tumours, were measured. Cells were analysed for cell cycle arrest, cell death mechanisms, reactive oxygen species production, mitochondrial depolarisation, oxygen consumption and acid production. Results PENAO demonstrated promising anti-proliferative activity on the most common (serous, endometrioid) as well as on rare (clear cell, mucinous) subtypes of ovarian cancer cell lines. No cross-resistance with platinum-based drugs was evident. Endometrioid SKOV-3 cells were, however, shown to be resistant to PENAO in vitro and in a xenograft mouse model. This resistance was due to an ability to cope with PENAO-induced oxidative stress, notably through heme oxygenase-1 induction, and a shift in metabolism towards glycolysis. The adaptive glycolytic shift in SKOV-3 was targeted using a mTORC1 inhibitor in combination with PENAO. This strategy was successful with the two drugs acting synergistically to inhibit cell proliferation and to induce cell death via apoptosis and autophagy. Conclusion Mitochondria/mTOR dual-targeting therapy may constitute a new approach for the treatment of recurrent/resistant forms of epithelial ovarian cancer. [ABSTRACT FROM AUTHOR]

Background: Limited data exist to guide FODMAP (fermentable oligo‐, di‐, monosaccharides, and polyols) reintroduction to assess tolerance following a low FODMAP diet (LFD). Fructose reintroduction is often stepwise up to 7.5 g fructose (e.g., three tsp of honey). We aimed to determine the fructose tolerance threshold in non‐constipated, LFD‐responsive patients with irritable bowel syndrome (IBS) and assess whether stool microbiome predicted LFD response or fructose tolerance. Methods: Thirty‐nine non‐constipated IBS patients (51% women, mean age 33.7 years) completed a 4‐week LFD. LFD responders were defined as those who reported adequate relief of IBS symptoms following the LFD. Responders were randomized to one of the three solution groups (100% fructose, 56% fructose/44% glucose, or 100% glucose) and received four doses (2.5, 5, 10, 15 g) for 3 days each. Patients reached their tolerance dose if their mean daily IBS symptom severity (visual analog scale [VAS], 0–100 mm) was >20 mm higher than post‐LFD VAS. Stool samples before and after LFD were analyzed using shotgun metagenomics. Results: Seventy‐nine percent of patients were LFD responders. Most responders tolerated the 15 g sugar dose. There was no significant difference in mean dose tolerated between solution groups (p = 0.56). Compared to baseline, microbiome composition (beta diversity) significantly shifted and six bacterial genes in fructose and mannose metabolism pathways decreased after LFD, irrespective of LFD response or the solution group. Conclusions: Non‐constipated, LFD‐responsive IBS patients should be reintroduced to fructose in higher doses than 15 g to assess tolerance. LFD is associated with significant changes in microbial composition and bacterial genes involved in FODMAP metabolism. [ABSTRACT FROM AUTHOR]

Background: Evidence supports a role for the gut-brain axis in Parkinson's disease (PD). Mice overexpressing human wild type α– synuclein (Thy1-haSyn) exhibit slow colonic transit prior to motor deficits, mirroring prodromal constipation in PD. Identifying molecular changes in the gut could provide both biomarkers for early diagnosis and gut-targeted therapies to prevent progression. Objective: To identify early molecular changes in the gut-brain axis in Thy1-haSyn mice through gene expression profiling. Methods: Gene expression profiling was performed on gut (colon) and brain (striatal) tissue from Thy1-haSyn and wild-type (WT) mice aged 1 and 3 months using 3′ RNA sequencing. Analysis included differential expression, gene set enrichment and weighted gene co-expression network analysis (WGCNA). Results: At one month, differential expression (Thy1-haSyn vs. WT) of mitochondrial genes and pathways related to PD was discordant between gut and brain, with negative enrichment in brain (enriched in WT) but positive enrichment in gut. Linear regression of WGCNA modules showed partial independence of gut and brain gene expression changes. Thy1-haSyn-associated WGCNA modules in the gut were enriched for PD risk genes and PD-relevant pathways including inflammation, autophagy, and oxidative stress. Changes in gene expression were modest at 3 months. Conclusions: Overexpression of haSyn acutely disrupts gene expression in the colon. While changes in colon gene expression are highly related to known PD-relevant mechanisms, they are distinct from brain changes, and in some cases, opposite in direction. These findings are in line with the emerging view of PD as a multi-system disease. [ABSTRACT FROM AUTHOR]

Background: Late stage Ovarian Cancer is essentially incurable primarily due to late diagnosis and its inherent heterogeneity. Single agent treatments are inadequate and generally lead to severe side effects at therapeutic doses. It is crucial to develop clinically relevant novel combination regimens involving synergistic modalities that target a wider repertoire of cells and lead to lowered individual doses. Stemming from this premise, this is the first report of two- and three-way synergies between Adenovirus-mediated Purine Nucleoside Phosphorylase based gene directed enzyme prodrug therapy (PNP-GDEPT), docetaxel and/or carboplatin in multidrug-resistant ovarian cancer cells.Methods: The effects of PNP-GDEPT on different cellular processes were determined using Shotgun Proteomics analyses. The in vitro cell growth inhibition in differentially treated drug resistant human ovarian cancer cell lines was established using a cell-viability assay. The extent of synergy, additivity, or antagonism between treatments was evaluated using CalcuSyn statistical analyses. The involvement of apoptosis and implicated proteins in effects of different treatments was established using flow cytometry based detection of M30 (an early marker of apoptosis), cell cycle analyses and finally western blot based analyses.Results: Efficacy of the trimodal treatment was significantly greater than that achieved with bimodal- or individual treatments with potential for 10-50 fold dose reduction compared to that required for individual treatments. Of note was the marked enhancement in apoptosis that specifically accompanied the combinations that included PNP-GDEPT and accordingly correlated with a shift in the expression of anti- and pro-apoptotic proteins. PNP-GDEPT mediated enhancement of apoptosis was reinforced by cell cycle analyses. Proteomic analyses of PNP-GDEPT treated cells indicated a dowregulation of proteins involved in oncogenesis or cancer drug resistance in treated cells with accompanying upregulation of apoptotic- and tumour- suppressor proteins.Conclusion: Inclusion of PNP-GDEPT in regular chemotherapy regimens can lead to significant enhancement of the cancer cell susceptibility to the combined treatment. Overall, these data will underpin the development of regimens that can benefit patients with late stage ovarian cancer leading to significantly improved efficacy and increased quality of life. [ABSTRACT FROM AUTHOR]

Background: Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are chronic gastrointestinal (GI) disorders. GI symptom‐specific anxiety (GSA) is the cognitive, affective, and behavioral response stemming from fear of GI symptoms. The Visceral Sensitivity Index (VSI) measures GSA and is validated in IBS and may be useful in IBD. Methods: We compared VSI scores in IBD participants to IBS participants and healthy controls (HCs). Using validated questionnaires, we assessed the VSI's correlation with anxiety, health‐related quality of life (HRQOL), and IBD activity. Key Results: We recruited 222 age‐ and sex‐matched participants (74 IBD [23 Crohn's disease; 51 ulcerative colitis], 74 IBS, and 74 HCs). IBD and IBS participants had higher VSI scores compared with HCs (IBD = 26.62 ± 16.64, IBS = 38.83 ± 15.06; HCs = 3.42±5.06; all p's < 0.001). VSI scores were lower in IBD vs IBS (p < 0.001). In IBD, VSI modestly correlated with current anxiety (R = 0.35, p = 0.002) and the physical component of HRQOL (R = −0.45, p = 0.0001) but less with the mental component of HRQOL (R = −0.23, p = 0.05). Conclusions & Inferences: Our findings suggest the VSI is a useful measure in IBD. The VSI in IBD is related to general anxiety but is measuring a different construct and is not affected by the presence of trait anxiety. IBD patients have GSA that is associated with decreased HRQOL, which can negatively affect treatment compliance and other long‐term disease outcomes. Future studies are needed to further validate the VSI in IBD and to assess its correlation with disease activity. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with low survival rates and limited therapeutic options. Thus elucidation of signaling pathways involved in PDAC pathogenesis is essential for identifying novel potential therapeutic gene targets. Here, we used a systems approach to elucidate those pathways by integrating gene and microRNA profiling analyses together with CRISPR/Cas9 technology to identify novel transcription factors involved in PDAC pathogenesis. FOXA2 transcription factor was found to be significantly downregulated in PDAC relative to control pancreatic tissues. Functional experiments revealed that FOXA2 has a tumor suppressor function through inhibition of pancreatic cancer cell growth, migration, invasion, and colony formation. In situ hybridization analysis revealed miR-199a to be significantly upregulated in pancreatic cancer. Bioinformatics and luciferase analyses showed that miR-199a negatively but directly regulates FOXA2 expression through binding in its 3'-untranslated region (UTR). Evaluation of the functional importance of miR-199a on pancreatic cancer revealed that miR-199a acts as an inhibitor of FOXA2 expression, inducing an increase in pancreatic cancer cell proliferation, migration, and invasion. Additionally, gene ontology and network analyses in PANC-1 cells treated with a small interfering RNA (siRNA) against FOXA2 revealed an enrichment for cell invasion mechanisms through PLAUR and ERK activation. FOXA2 deletion (FOXA2Δ) by using two CRISPR/Cas9 vectors in PANC-1 cells induced tumor growth in vivo resulting in upregulation of PLAUR and ERK pathways in FOXA2Δ xenograft tumors. We have identified FOXA2 as a novel tumor suppressor in pancreatic cancer and it is regulated directly by miR-199a, thereby enhancing our understanding of how microRNAs interplay with the transcription factors to affect pancreatic oncogenesis. [ABSTRACT FROM AUTHOR]

Pediatric high grade gliomas (HGG) are primary brain malignancies that result in significant morbidity and mortality. One of the challenges in their treatment is inter- and intra-tumoral heterogeneity. Precision medicine approaches have the potential to enhance diagnostic, prognostic and/or therapeutic information. In this case study we describe the molecular characterization of a pediatric HGG and the use of an integrated approach based on genomic, in vitro and in vivo testing to identify actionable targets and treatment options. Molecular analysis based on WGS performed on initial and recurrent tumor biopsies revealed mutations in TP53, TSC1 and CIC genes, focal amplification of MYCN, and copy number gains in SMO and c-MET. Transcriptomic analysis identified increased expression of MYCN, and genes involved in sonic hedgehog signaling proteins (SHH, SMO, GLI1, GLI2) and receptor tyrosine kinase pathways (PLK, AURKA, c-MET). HTS revealed no cytotoxic efficacy of SHH pathway inhibitors while sensitivity was observed to the mTOR inhibitor temsirolimus, the ALK inhibitor ceritinib, and the PLK1 inhibitor BI2536. Based on the integrated approach, temsirolimus, ceritinib, BI2536 and standard therapy temozolomide were selected for further in vivo evaluation. Using the PDX animal model (median survival 28 days) we showed significant in vivo activity for mTOR inhibition by temsirolimus and BI2536 (median survival 109 and 115.5 days respectively) while ceritinib and temozolomide had only a moderate effect (43 and 75.5 days median survival respectively). This case study demonstrates that an integrated approach based on genomic, in vitro and in vivo drug efficacy testing in a PDX model may be useful to guide the management of high risk pediatric brain tumor in a clinically meaningful timeframe. [ABSTRACT FROM AUTHOR]

Background: The O 6 -methylguanine methyltransferase (MGMT) gene is frequently unmethylated in patients with glioblastoma (GBM), rendering them non-responsive to the standard treatment regime of surgery followed by concurrent radiotherapy (RT) and temozolomide. Here, we investigate the efficacy of adding a PARP inhibitor, veliparib, to radiotherapy to treat MGMT unmethylated GBM.Methods: The inhibition of PARP with veliparib (ABT-888), a potent and orally bioavailable inhibitor in combination with RT was tested on a panel of patient derived cell lines (PDCLs) and patient-derived xenografts (PDX) models generated from GBM patients with MGMT unmethylated tumors.Results: The combination of veliparib and RT inhibited colony formation in the majority of PDCLs tested. The PDCL, RN1 showed significantly reduced levels of the homologous repair protein, Mre11 and a heightened response to PARP inhibition measured by increased apoptosis and decreased colony formation. The oral administration of veliparib (12.5 mg/kg, twice daily for 5 days in a 28-day treatment cycle) in combination with whole brain RT (4 Gy) induced apoptosis (Tunel staining) and decreased cell proliferation (Ki67 staining) in a PDX of MGMT unmethylated GBM. Significantly longer survival times of the PDX treated with the combination treatment were recorded compared to RT only or veliparib only.Conclusions: Our results demonstrate preclinical efficacy of targeting PARP at multiple levels and provide a new approach for the treatment of MGMT unmethylated GBM. [ABSTRACT FROM AUTHOR]

Background and aims Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been reported in irritable bowel syndrome (IBS). Enhanced HPA axis response has been associated with reduced glucocorticoid receptor (GR) mediated negative feedback inhibition. We aimed to study the effects of IBS status, sex, or presence of early adverse life events (EAL) on the cortisol response to corticotropin-releasing factor (CRF) and adrenocorticotropic hormone (ACTH), and on GR mRNA expression in peripheral blood mononuclear cells (PBMCs). Methods Rome III+ IBS patients and healthy controls underwent CRF (1 μg/kg ovine) and ACTH (250 μg) stimulation tests with serial plasma ACTH and cortisol levels measured (n = 116). GR mRNA levels were measured using quantitative PCR (n = 143). Area under the curve (AUC) and linear mixed effects models were used to compare ACTH and cortisol response measured across time between groups. Results There were divergent effects of IBS on the cortisol response to ACTH by sex. In men, IBS was associated with an increased AUC (p = 0.009), but in women AUC was blunted in IBS (p = 0.006). Men also had reduced GR mRNA expression (p = 0.007). Cumulative exposure to EALs was associated with an increased HPA response. Lower GR mRNA was associated with increased pituitary HPA response and increased severity of overall symptoms and abdominal pain in IBS. Conclusion This study highlights the importance of considering sex in studies of IBS and the stress response in general. Our findings also provide support for PBMC GR mRNA expression as a peripheral marker of central HPA response. [ABSTRACT FROM AUTHOR]

R4859 --> 626.6 --> Background: Alterations in the gut brain axis are being recognized as a pathogenic factor for an increasing number of diseases, including neurodegenerative diseases such as Parkinson Disease (PD). The extent to which gene expression profiling in the gut and the brain is co‐regulated is not well understood. Weighted gene coexpression network analysis (WGCNA) uses unbiased hierarchical clustering to reduce gene expression profiling data to modules of highly correlated genes. Hypothesis: Gut‐brain connectivity will be strongest for modules related to physiologic mechanisms with a systemic component, such as immune reactivity. Methods: WGNCA networks were constructed for distal colon and striatum RNA seq data from mice overexpressing human wild type alpha synuclein (ASO, n=18) and wild type (WT, n=16) mice at 1 and 3 months. Mice with matched colon and striatum data (n=10/6 ASO/WT) were included in this analysis. Linear regression identified associations between colon and striatum modules. For this analysis, we controlled for both age and genotype as genotype‐ and age‐associated modules could be correlated due to these covariates alone. Colon‐striatum intermodular connectivity was visualized in Cytoscape. Overrepresented gene ontology (GO) terms in WGCNA modules were determined using the hypergeometric function in the GOstats package in R. Enrichment for gene signatures from single cell sequencing data was determined using the hypergeometric test against cell type signatures from the Panglao and Cellmarker databases. Results: Selected associations are shown in Figure 1. There are strong correlations between colon and striatum modules that are enriched for terms related to the immune response. Modules most clearly related to the immune response are highlighted in yellow, but several other modules are also closely related to the immune response. For example, there is an association between the striatum module enriched for endothelial cells of the blood brain barrier, and the colon module enriched for goblet cells which produce the mucus layer of the epithelium, a key component of the innate immune system. Conclusions: Through analysis of matched colon and striatum samples, we can see correlations between gene expression in the colon and striatum. Most modules in this gut‐brain network have some relevance to the immune system which is not unexpected. These results demonstrate the feasibility of "profiling" the gut‐brain axis. A larger sample size would permit evaluation of disease‐related changes in this profile. [ABSTRACT FROM AUTHOR]

Introduction: Animal studies have shown that stress could induce epigenetic and transcriptomic alterations essential in determining the balance between adaptive or maladaptive responses to stress. We tested the hypothesis that chronic stress in rats deregulates coding and non-coding gene expression in the spinal cord, which may underline neuroinflammation and nociceptive changes previously observed in this model. Methods: Male Wistar rats were exposed to daily stress or handled, for 10 days. At day 11, lumbar spinal segments were collected and processed for mRNA/miRNA isolation followed by expression profiling using Agilent SurePrint Rat Exon and Rat miRNA Microarray platforms. Differentially expressed gene lists were generated using the dChip program. Microarrays were analyzed using the Ingenuity Pathways Analysis (IPA) tool from Ingenuity Systems. Multiple methods were used for the analysis of miRNA-mRNA functional modules. Quantitative real time RT-PCR for Interleukin 6 signal transducer (gp130), the Signal Transducer And Activator Of Transcription 3 (STAT3), glial fibrillary acidic protein and mir-17-5p were performed to confirm levels of expression. Results: Gene network analysis revealed that stress deregulated different inflammatory (IL-6, JAK/STAT, TNF) and metabolic (PI3K/AKT) signaling pathways. MicroRNA array analysis revealed a signature of 39 deregulated microRNAs in stressed rats. MicroRNA-gene network analysis showed that microRNAs are regulators of two gene networks relevant to inflammatory processes. Specifically, our analysis of miRNA-mRNA functional modules identified miR-17-5p as an important regulator in our model. We verified miR-17-5p increased expression in stress using qPCR and in situ hybridization. In addition, we observed changes in the expression of gp130 and STAT3 (involved in intracellular signaling cascades in response to gp130 activation), both predicted targets for miR-17-5p. A modulatory role of spinal mir17-5p in the modulation of visceral sensitivity was confirmed in vivo. Conclusion: Using an integrative high throughput approach, our findings suggest a link between miR-17-5p increased expression and gp130/STAT3 activation providing new insight into the possible mechanisms mediating the effect of chronic stress on neuroinflammation in the spinal cord. [ABSTRACT FROM AUTHOR]

Adoptive therapy with chimeric antigen receptor (CAR) T cells (CART cells) has exhibited great promise in clinical trials, with efficient response correlated with CART-cell expansion and persistence. Despite extensive clinical use, the mechanisms regulating CART-cell expansion and persistence have not been completely elucidated. We have examined the antileukemia potency of CART cells targeting CD19 antigen using second-generation CAR containing a CD28 co-stimulatory domain cloned into piggyBac-transposon vector and patient-derived chemoresistant pediatric acute lymphoblastic leukemia samples. In the presence of large numbers of target cells characteristic of patients with high leukemia burden, excessive proliferation of CART cells leads to differentiation into short-lived effector cells. Transient leukemia growth delay was induced by CART-cell infusion in mice xenografted with rapidly growing CD19+ acute lymphoblastic leukemia cells and was followed by rapid CART-cell extinction. Conditioning with the hypomethylating agent 5-aza-2'-deoxycytidine-activating caspase 3 and promotion of apoptosis in leukemia cells maximized the effect of CART cells and improved CART-cell persistence. These data suggest that the clinical use of 5-aza-2'-deoxycytidine before CART cells could be considered. Coculture of leukemia cells with bone marrow stroma cells reduced target cell loss, suggesting that leukemia cell mobilization into circulation may help to remove the protective effect of bone marrow stroma and increase the efficacy of CART-cell therapy. [ABSTRACT FROM AUTHOR]