Phosphatidylcholine-deficient suppressor mutant of Sinorhizobium meliloti, altered in fatty acid synthesis, partially recovers nodulation ability in symbiosis with alfalfa (Medicago sativa).

Rhizobial phosphatidylcholine (PC) is thought to be a critical phospholipid for the symbiotic relationship between rhizobia and legume host plants. A PC-deficient mutant of Sinorhizobium meliloti overproduces succinoglycan, is unable to swim, and lacks the ability to form nodules on alfalfa (Medicago sativa) host roots. Suppressor mutants had been obtained which did not overproduce succinoglycan and regained the ability to swim. Previously, we showed that point mutations leading to altered ExoS proteins can reverse the succinoglycan and swimming phenotypes of a PC-deficient mutant. Here, we report that other point mutations leading to altered ExoS, ChvI, FabA, or RpoH1 proteins also revert the succinoglycan and swimming phenotypes of PC-deficient mutants. Notably, the suppressor mutants also restore the ability to form nodule organs on alfalfa roots. However, nodules generated by these suppressor mutants express only low levels of an early nodulin, do not induce leghemoglobin transcript accumulation, thus remain white, and are unable to fix nitrogen. Among these suppressor mutants, we detected a reduced function mutant of the 3-hydoxydecanoyl-acyl carrier protein dehydratase FabA that produces reduced amounts of unsaturated and increased amounts of shorter chain fatty acids. This alteration of fatty acid composition probably affects lipid packing thereby partially compensating for the previous loss of PC and contributing to the restoration of membrane homeostasis.

[Comparison of different tools for the evaluation of malnutrition and sarcopenia in patients with liver cirrhosis]. / Comparación de distintas herramientas para la evaluación de la malnutrición y la sarcopenia en pacientes con cirrosis hepática.

Introduction: Introduction: malnutrition and sarcopenia are frequent in the population with liver cirrhosis and have a negative impact on the performance status and life expectancy of these patients. There are multiple assessment tools for malnutrition and sarcopenia in cirrhosis. Objective: to assess malnutrition and sarcopenia in liver cirrhosis and to compare the accuracy of diagnostic tools in this population. Method: a cross-sectional analytical study was conducted with convenience sampling by using continuous inclusion of patients with liver cirrhosis in a tertiary care center during December 2018 to May 2019. The nutritional assessment was carried out with arm anthropometry, body mass index (BMI), and the algorithm of the Royal Free Hospital Subjective Global Assessment (RFH-SGA). For the evaluation of sarcopenia, the hand grip strength test with a hand dynamometer was applied. The results were reported in measures of central tendency expressed in frequency and percentage. Results: a total of 103 patients were included with a predominance of the male gender (79.6 %) and a mean age of 51 years (± 10). The etiology of liver cirrhosis corresponded more frequently to alcohol consumption (68 %) and most of the patients were Child-Pugh C (57.3 %) with a mean MELD of 21.9 (± 8.9). A mean BMI with dry weight of 25.2 kg/m2 was reported, and with respect to the WHO classification by BMI, 7.8 % were underweight and 59.2 % were malnourished by RFH-SGA. Sarcopenia was present in 88.3 % using the hand grip strength test, for which a mean of 18.99 kg was found. A Kendall's Tau-b rank correlation coefficient was performed between BMI and RFH-SGA, which showed no statistically significant association, as well as between mean arm muscle circumference percentiles and hand grip strength. Conclusions: global assessment in liver cirrhosis should include screening for malnutrition and sarcopenia, for which validated, accessible and safe application tools should be used, such as anthropometric assessment, RFH-SGA, and hand grip strength.

Introducción: Introducción: la malnutrición y la sarcopenia son frecuentes en la población con cirrosis hepática y generan un impacto negativo en el estado funcional y la esperanza de vida de estos pacientes. Existen múltiples herramientas para la valoración de la malnutrición y la sarcopenia en los pacientes con cirrosis hepática. Objetivo: valorar la malnutrición y la sarcopenia en la cirrosis hepática y comparar distintas herramientas diagnósticas aplicables en esta población. Método: se realizó un estudio analítico de corte transversal con muestreo a conveniencia mediante inclusión continua de pacientes con cirrosis hepática en un hospital de tercer nivel durante diciembre de 2018 a mayo de 2019. Se realizó la valoración nutricional con la antropometría del brazo, el índice de masa corporal (IMC) y el algoritmo del Royal Free Hospital Subjetive Global Assessment (RFH-SGA). Para la valoración de la sarcopenia se aplicó la fuerza de agarre de la mano con un dinamómetro. Los resultados se reportaron en medidas de tendencia central expresadas en frecuencia y porcentaje. Resultados: se incluyeron un total de 103 pacientes, predominando el género masculino (79,6 %), con una edad media de 51 años. La etiología más frecuente de la cirrosis hepática fue el consumo de alcohol (68 %), predominando la clase Child-Pugh C (57,3 %) con una media de MELD de 21,9 (± 8,9). Se reportó una media de IMC con peso seco de 25,2 kg/m2 y, respecto a la clasificación de la OMS, un 7,8 % se encontraban en bajo peso y un 59,2 % en malnutrición según la RFH-SGA. Un 88,3 % presentó sarcopenia al utilizar la fuerza de agarre de la mano, cuyo valor medio fue de 18,99 kg. Se realizó una correlación con Tau b de Kendall entre IMC y RFH-SGA sin evidenciarse ninguna asociación significativa, al igual que entre los percentiles de la circunferencia muscular media de brazo (MAMC) y la fuerza de agarre de la mano. Conclusiones: la valoración integral de la cirrosis hepática debe incluir el escrutinio de la malnutrición y la sarcopenia, existiendo herramientas de fácil acceso y aplicación segura validadas en esta población, como la valoración antropométrica, el RFH-SGA y la fuerza de agarre de la mano.

Escherichia/Shigella, SCFAs, and Metabolic Pathways-The Triad That Orchestrates Intestinal Dysbiosis in Patients with Decompensated Alcoholic Cirrhosis from Western Mexico.

Gut microbiota undergoes profound alterations in alcohol cirrhosis. Microbiota-derived products, e.g., short chain fatty acids (SCFA), regulate the homeostasis of the gut-liver axis. The objective was to evaluate the composition and functions of the intestinal microbiota in patients with alcohol-decompensated cirrhosis. Fecal samples of 18 patients and 18 healthy controls (HC) were obtained. Microbial composition was characterized by 16S rRNA amplicon sequencing, SCFA quantification was performed by gas chromatography (GC), and metagenomic predictive profiles were analyzed by PICRUSt2. Gut microbiota in the cirrhosis group revealed a significant increase in the pathogenic/pathobionts genera Escherichia/Shigella and Prevotella, a decrease in beneficial bacteria, such as Blautia, Faecalibacterium, and a decreased α-diversity (p < 0.001) compared to HC. Fecal SCFA concentrations were significantly reduced in the cirrhosis group (p < 0.001). PICRUSt2 analysis indicated a decrease in acetyl-CoA fermentation to butyrate, as well as an increase in pathways related to antibiotics resistance, and aromatic amino acid biosynthesis. These metabolic pathways have been poorly described in the progression of alcohol-related decompensated cirrhosis. The gut microbiota of these patients possesses a pathogenic/inflammatory environment; therefore, future strategies to balance intestinal dysbiosis should be implemented. These findings are described for the first time in the population of western Mexico.

Position statement on the use of albumin in liver cirrhosis.

Cirrhosis is characterised by a prolonged asymptomatic period in which the inflammation persists, increasing as the disease progresses. Characteristic of this is the increase in pro-inflammatory cytokines and pro-oxidant molecules which are determining factors in the development of multiple organ dysfunction. In the early development of cirrhosis, splanchnic arterial vasodilation, activation of vasoconstrictor systems (renin-angiotensin-aldosterone) and the sympathetic nervous system (noradrenaline) bring about bacterial translocation and systemic dissemination via portal circulation of bacterial products, and molecular patterns associated with damage, which exacerbate the systemic inflammation present in the patient with cirrhosis. Albumin is a molecule that undergoes structural and functional changes as liver damage progresses, affecting its antioxidant, immunomodulatory, oncotic and endothelial stabilising properties. Our knowledge of the properties of albumin reveals a molecule with multiple treatment options in patients with cirrhosis, from the compensated then decompensated phases to multiple organ dysfunction. Its recognised uses in spontaneous bacterial peritonitis, post-paracentesis circulatory dysfunction, acute kidney injury and hepatorenal syndrome are fully validated, and a treatment option has opened up in decompensated cirrhosis and in acute-on-chronic liver disease.

Prevalence of hepatitis B immunity and infection in home self-sampling HIV service users.

OBJECTIVES: Although hepatitis B virus (HBV) vaccination for high-risk groups including gay, bisexual and other men who have sex with men (MSM) is recommended in the UK, data on HBV immunisation coverage are limited. This study aimed to understand the prevalence of HBV infection, susceptibility and immunity due to immunisation among a high-risk population of MSM and heterosexuals who are less likely to attend sexual health services. METHODS: Residual HIV-negative serology samples archived from a national HIV self-sampling service in 2016 were tested for HBV markers using an unlinked anonymous approach. Prevalence of HBV infection, evidence of immunisation and susceptibility were calculated and stratified by individuals' characteristics. Multinomial logistic regression was used to estimate relative risk ratios (RRRs) associated with covariates. RESULTS: Of 2172 samples tested, 1497 (68.9%) were from MSM and 657 (30.2%) were from heterosexuals. Susceptibility to HBV infection was 66.1% among MSM and 77.0% among heterosexuals. Only 29.9% of MSM and 17.4% of heterosexuals had serological evidence of immunisation. Current infection was 1.1% in heterosexuals and 0.2% in MSM. Adjusted analysis showed evidence of immunisation was lower among heterosexuals (RRR 0.66, 95% CI 0.50 to 0.86) and those with no previous HIV test (RRR 0.41, 95% CI 0.31 to 0.54), and higher in those of other white or other ethnicity. CONCLUSIONS: Among MSM and heterosexual users of a self-sampling HIV service, evidence of immunisation to HBV infection was low and susceptibility to infection was comparatively high, suggesting suboptimal delivery of HBV immunisation in sexual health services.

Clinical evaluation of a Hepatitis C Virus whole-genome sequencing pipeline for genotyping and resistance testing.

OBJECTIVES: We sought to evaluate clinically a hepatitis C virus (HCV) whole-genome, next-generation sequencing (NGS) pipeline that is agnostic to viral genotype. METHODS: Performance of the NGS pipeline was assessed through comparison of results with Sanger sequencing (SS) of partial HCV genomes. RESULTS: There was 98.7% (376/381) concordance for viral subtype between SS and NGS. The positive and negative per cent agreements for determination of resistance-associated substitutions were 97.8% (95% CI 92.5-99.4%) and 99.9% (95% CI 99.5-100.0%), respectively. The NGS pipeline was also able to detect novel subtypes, mixtures, recombinants, transiently occurring resistance mutations and distinguish re-infection with the same subtype from relapse. DISCUSSION: Particular scenarios where NGS may be used include settings without universal access to pan-genotypic antiviral regimens, those infected with a 'rare' subtype or who have been failed by first-line therapy, and in cases of suspected re-infection.

Activation of PI3K/Akt Signaling Pathway in Rat Hypothalamus Induced by an Acute Oral Administration of D-Pinitol.

D-Pinitol (DPIN) is a natural occurring inositol capable of activating the insulin pathway in peripheral tissues, whereas this has not been thoroughly studied in the central nervous system. The present study assessed the potential regulatory effects of DPIN on the hypothalamic insulin signaling pathway. To this end we investigated the Phosphatidylinositol-3-kinase (PI3K)/Protein Kinase B (Akt) signaling cascade in a rat model following oral administration of DPIN. The PI3K/Akt-associated proteins were quantified by Western blot in terms of phosphorylation and total expression. Results indicate that the acute administration of DPIN induced time-dependent phosphorylation of PI3K/Akt and its related substrates within the hypothalamus, indicating an activation of the insulin signaling pathway. This profile is consistent with DPIN as an insulin sensitizer since we also found a decrease in the circulating concentration of this hormone. Overall, the present study shows the pharmacological action of DPIN in the hypothalamus through the PI3K/Akt pathway when giving in fasted animals. These findings suggest that DPIN might be a candidate to treat brain insulin-resistance associated disorders by activating insulin response beyond the insulin receptor.

Cannabidiol prevents several of the behavioral alterations related to cocaine addiction in mice.

Cocaine dependence is a highly prevalent disease in modern society and lacks an effective treatment. Cannabidiol (CBD), a major non-psychoactive constituent of Cannabis sativa, has been shown to be a promising tool in the management of some neuropsychiatric disorders, including cocaine abuse. However, its therapeutic effects on the behavioral outcomes related to cocaine addiction remain unclear. The present research evaluates the effects of CBD (30, 60 and 120 mg/kg; injected intraperitoneally) on the acquisition, expression, extinction and reinstatement of cocaine (10 mg/kg)-induced conditioned place preference (CPP; Study 1); cocaine (25 mg/kg)-induced locomotor stimulation (Study 2); and cocaine withdrawal symptoms (Study 3) in male C57BL/6 J mice. The results show that CBD does not possess motivational properties in itself and does not modify the acquisition, expression or extinction of cocaine-induced CPP. Interestingly, when administered during the extinction phase of the cocaine-induced CPP, CBD (30 and 60 mg/kg) prevented priming-induced reinstatement of CPP. Moreover, CBD abolished cocaine-induced hyperactivity without altering the spontaneous locomotion of the animals. Furthermore, CBD (120 mg/kg) reduced the memory deficits induced by cocaine withdrawal in the object recognition test, though it did not reverse depressive-like symptoms measured in the tail suspension test. Overall, our data suggest that CBD can prevent the development of cocaine addiction, and, when administered during cocaine abstinence, may be of help in avoiding relapse to drug-seeking and in ameliorating the memory disturbances provoked by chronic consumption of cocaine.

Adolescent binge-ethanol accelerates cognitive impairment and ß-amyloid production and dysregulates endocannabinoid signaling in the hippocampus of APP/PSE mice.

Previous research in rodents suggests that the long-term neurobehavioral disturbances induced by chronic ethanol (EtOH) exposure could be due to endocannabinoid system (ECS) alterations. Moreover, ECS failure has been proposed to mediate the cognitive impairment and ß-amyloid production in Alzheimer disease (AD). Thus, in the present study, we evaluated the effects of adolescent EtOH binge drinking on the cognitive disturbances, hippocampal ß-amyloid levels, and in the ECS expression on a transgenic mouse model (APP/PSEN, AZ) of AD. We exposed AZ and wild-type mice to a binge-drinking treatment during adolescence. At 6 and 12 months of age, we evaluated hippocampal-dependent learning and memory: ß-amyloid concentrations and RNA and protein levels of cannabinoid type-2 receptors (CB2), diacylglycerol lipase-α (DAGLα), and monoacylglycerol lipase (MAGL) in the hippocampus. The results showed that binge-EtOH treatment worsens cognitive function and increases ß-amyloid levels in AZ. At 6 months, EtOH heightens CB2 (RNA and protein) and DAGLα (RNA) expression in wild type but not in AZ. On the contrary, EtOH enhances MAGL RNA expression only in AZ. At 12 months, AZ displays increased levels of CB2 (RNA and protein) and DAGLα (protein) compared with control. Similar to what happens at 6 months, EtOH induces an increase in CB2 gene expression in wild type but not in AZ; however, it augments CB2 and DAGLα protein levels in both genotypes. Therefore, we propose that adolescent binge drinking accelerates cognitive deficits associated with aging and AD. It also accelerates hippocampal ß-amyloid accumulation in AZ and affects differently the ECS response in wild type and AZ.

Can We Treat Neuroinflammation in Alzheimer's Disease?

Alzheimer's disease (AD), considered the most common type of dementia, is characterized by a progressive loss of memory, visuospatial, language and complex cognitive abilities. In addition, patients often show comorbid depression and aggressiveness. Aging is the major factor contributing to AD; however, the initial cause that triggers the disease is yet unknown. Scientific evidence demonstrates that AD, especially the late onset of AD, is not the result of a single event, but rather it appears because of a combination of risk elements with the lack of protective ones. A major risk factor underlying the disease is neuroinflammation, which can be activated by different situations, including chronic pathogenic infections, prolonged stress and metabolic syndrome. Consequently, many therapeutic strategies against AD have been designed to reduce neuro-inflammation, with very promising results improving cognitive function in preclinical models of the disease. The literature is massive; thus, in this review we will revise the translational evidence of these early strategies focusing in anti-diabetic and anti-inflammatory molecules and discuss their therapeutic application in humans. Furthermore, we review the preclinical and clinical data of nutraceutical application against AD symptoms. Finally, we introduce new players underlying neuroinflammation in AD: the activity of the endocannabinoid system and the intestinal microbiota as neuroprotectors. This review highlights the importance of a broad multimodal approach to treat successfully the neuroinflammation underlying AD.

Surveillance of HIV-1 transmitted integrase strand transfer inhibitor resistance in the UK.

BACKGROUND: HIV treatment guidelines have traditionally recommended that all HIV-positive individuals are tested for evidence of drug resistance prior to starting ART. Testing for resistance to reverse transcriptase inhibitors and PIs is well established in routine care. However, testing for integrase strand transfer inhibitor (InSTI) resistance is less consistent. OBJECTIVES: To inform treatment guidelines by determining the prevalence of InSTI resistance in a national cohort of recently infected individuals. PATIENTS AND METHODS: Recent (within 4 months) HIV-1 infections were identified using a Recent Infection Testing Algorithm of new HIV-1 diagnoses in the UK. Resistance-associated mutations (RAMs) in integrase, protease and reverse transcriptase were detected by ultradeep sequencing, which allows for the sensitive estimation of the frequency of each resistant variant in a sample. RESULTS: The analysis included 655 randomly selected individuals (median age = 33 years, 95% male, 83% MSM, 78% white) sampled in the period 2014 to 2016 and determined to have a recent infection. These comprised 320, 138 and 197 samples from 2014, 2015 and 2016, respectively. None of the samples had major InSTI RAMs occurring at high variant frequency (≥20%). A subset (25/640, 3.9%) had major InSTI RAMs occurring only as low-frequency variants (2%-20%). In contrast, 47/588 (8.0%) had major reverse transcriptase inhibitor and PI RAMs at high frequency. CONCLUSIONS: Between 2014 and 2016, major InSTI RAMs were uncommon in adults with recent HIV-1 infection, only occurring as low-frequency variants of doubtful clinical significance. Continued surveillance of newly diagnosed patients for evidence of transmitted InSTI resistance is recommended to inform clinical practice.

Resolution by deep sequencing of a dual hepatitis E virus infection transmitted via blood components.

Hepatitis E virus (HEV) is a zoonotic infection, with consumption of processed pork products thought to be the major route of transmission in England. The clinical features of HEV infection range from asymptomatic infection to mild hepatitis to fulminant liver failure. Persistent, chronic hepatitis is increasingly recognized in immunocompromised patients. Infection via HEV-containing blood components and organs has been reported and measures to reduce this transmission risk were introduced into the blood service in England in 2016. We report here the sequence and phylogenetic findings from investigations into a transmission event from an HEV-infected donor to two recipients. Phylogenetic analysis of HEV genome sequence fragments obtained by Sanger sequencing showed that, whilst most of the sequences from both recipients' samples grouped with the sequence from the blood donor sample, the relationship of five sequences from recipient 2 were unresolved. Analysis of Illumina short-read deep sequence data demonstrated the presence of two divergent viral populations in the donor's sample that were also present in samples from both recipients. A clear phylogenetic relationship was established, indicating a probable transmission of both populations from the donor to each of the immunocompromised recipients. This study demonstrates the value of the application of new sequencing technologies combined with bioinformatic data analysis when Sanger sequencing is not able to clarify a proper phylogenetic relationship in the investigation of transmission events.

Buparlisib in Patients With Recurrent Glioblastoma Harboring Phosphatidylinositol 3-Kinase Pathway Activation: An Open-Label, Multicenter, Multi-Arm, Phase II Trial.

PURPOSE: Phosphatidylinositol 3-kinase (PI3K) signaling is highly active in glioblastomas. We assessed pharmacokinetics, pharmacodynamics, and efficacy of the pan-PI3K inhibitor buparlisib in patients with recurrent glioblastoma with PI3K pathway activation. METHODS: This study was a multicenter, open-label, multi-arm, phase II trial in patients with PI3K pathway-activated glioblastoma at first or second recurrence. In cohort 1, patients scheduled for re-operation after progression received buparlisib for 7 to 13 days before surgery to evaluate brain penetration and modulation of the PI3K pathway in resected tumor tissue. In cohort 2, patients not eligible for re-operation received buparlisib until progression or unacceptable toxicity. Once daily oral buparlisib 100 mg was administered on a continuous 28-day schedule. Primary end points were PI3K pathway inhibition in tumor tissue and buparlisib pharmacokinetics in cohort 1 and 6-month progression-free survival (PFS6) in cohort 2. RESULTS: Sixty-five patients were treated (cohort 1, n = 15; cohort 2, n = 50). In cohort 1, reduction of phosphorylated AKTS473 immunohistochemistry score was achieved in six (42.8%) of 14 patients, but effects on phosphoribosomal protein S6S235/236 and proliferation were not significant. Tumor-to-plasma drug level was 1.0. In cohort 2, four (8%) of 50 patients reached 6-month PFS6, and the median PFS was 1.7 months (95% CI, 1.4 to 1.8 months). The most common grade 3 or greater adverse events related to treatment were lipase elevation (n = 7 [10.8%]), fatigue (n = 4 [6.2%]), hyperglycemia (n = 3 [4.6%]), and elevated ALT (n = 3 [4.6%]). CONCLUSION: Buparlisib had minimal single-agent efficacy in patients with PI3K-activated recurrent glioblastoma. Although buparlisib achieved significant brain penetration, the lack of clinical efficacy was explained by incomplete blockade of the PI3K pathway in tumor tissue. Integrative results suggest that additional study of PI3K inhibitors that achieve more-complete pathway inhibition may still be warranted.

Determining the Origins of Human Immunodeficiency Virus Type 1 Drug-resistant Minority Variants in People Who Are Recently Infected Using Phylogenetic Reconstruction.

BACKGROUND: Drug-resistant minority variants (DRMinVs) detected in patients who recently acquired human immunodeficiency virus type 1 (HIV-1) can be transmitted, generated de novo through virus replication, or technical errors. The first form is likely to persist and result in treatment failure, while the latter two could be stochastic and transient. METHODS: Ultradeep sequencing of plasma samples from 835 individuals with recent HIV-1 infection in the United Kingdom was performed to detect DRMinVs at a mutation frequency between 2% and 20%. Sequence alignments including >110 000 HIV-1 partial pol consensus sequences from the UK HIV Drug Resistance Database (UK-HDRD), linked to epidemiological and clinical data from the HIV and AIDS Reporting System, were used for transmission cluster analysis. Transmission clusters were identified using Cluster Picker with a clade support of >90% and maximum genetic distances of 4.5% or 1.5%, the latter to limit detection to likely direct transmission events. RESULTS: Drug-resistant majority variants (DRMajVs) were detected in 66 (7.9%) and DRMinVs in 84 (10.1%) of the recently infected individuals. High levels of clustering to sequences in UK-HDRD were observed for both DRMajV (n = 48; 72.7%) and DRMinV (n = 63; 75.0%) sequences. Of these, 43 (65.2%) with DRMajVs were in a transmission cluster with sequences that harbored the same DR mutation compared to only 3 (3.6%) sequences with DRMinVs (P < .00001, Fisher exact test). Evidence of likely direct transmission of DRMajVs was observed for 25/66 (37.9%), whereas none were observed for the DRMinVs (P < .00001). CONCLUSIONS: Using a densely sampled HIV-infected population, we show no evidence of DRMinV transmission among recently infected individuals.

Author Correction: Mutations in the SWI/SNF complex induce a targetable dependence on oxidative phosphorylation in lung cancer.

In the version of this article originally published, information regarding several funding sources was omitted from the Acknowledgements section. The following sentences should have been included: "This work was supported by the generous philanthropic contributions to The University of Texas MD Anderson Lung Cancer Moon Shots Program, the UT Lung SPORE 5 P50 CA07090, and the MD Anderson Cancer Center Support Grant P30CA01667. V.P is supported by R01CA155196-01A1 from the National Cancer Institute." Also, reference 18 was incorrect. The original reference was: Kim, E. S. et al. The BATTLE trial: personalizing therapy for lung cancer. Cancer Discov. 1, 44-53 (2011). It should have been: Papadimitrakopoulou, V. et al. The BATTLE-2 study: a biomarker-integrated targeted therapy study in previously treated patients with advanced non-small-cell lung cancer. J Clin. Oncol. 34, 3638-3647 (2016). The errors have been corrected in the HTML and PDF versions of this article.

Mutations in the SWI/SNF complex induce a targetable dependence on oxidative phosphorylation in lung cancer.

Lung cancer is a devastating disease that remains a top cause of cancer mortality. Despite improvements with targeted and immunotherapies, the majority of patients with lung cancer lack effective therapies, underscoring the need for additional treatment approaches. Genomic studies have identified frequent alterations in components of the SWI/SNF chromatin remodeling complex including SMARCA4 and ARID1A. To understand the mechanisms of tumorigenesis driven by mutations in this complex, we developed a genetically engineered mouse model of lung adenocarcinoma by ablating Smarca4 in the lung epithelium. We demonstrate that Smarca4 acts as a bona fide tumor suppressor and cooperates with p53 loss and Kras activation. Gene expression analyses revealed the signature of enhanced oxidative phosphorylation (OXPHOS) in SMARCA4 mutant tumors. We further show that SMARCA4 mutant cells have enhanced oxygen consumption and increased respiratory capacity. Importantly, SMARCA4 mutant lung cancer cell lines and xenograft tumors have marked sensitivity to inhibition of OXPHOS by a novel small molecule, IACS-010759, that is under clinical development. Mechanistically, we show that SMARCA4-deficient cells have a blunted transcriptional response to energy stress creating a therapeutically exploitable synthetic lethal interaction. These findings provide the mechanistic basis for further development of OXPHOS inhibitors as therapeutics against SWI/SNF mutant tumors.

Novel therapeutic strategy for cervical cancer harboring FGFR3-TACC3 fusions.

We previously found that therapeutic targetable fusions are detected across various cancers. To identify therapeutic targetable fusion in uterine cervical cancer, for which no effective gene targeted therapy has yet been clinically applied, we analyzed RNA sequencing data from 306 cervical cancer samples. We detected 445 high confidence fusion transcripts and identified four samples that harbored FGFR3-TACC3 fusion as an attractive therapeutic target. The frequency of FGFR3-TACC3-fusion-positive cervical cancer is also 1.9% (2/103) in an independent cohort. Continuous expression of the FGFR3-TACC3 fusion transcript and protein induced anchorage-independent growth in the cervical epithelial cell line established from the ectocervix (Ect1/E6E7) but not in that from endocervix (End1/E6E7). Injection of FGFR3-TACC3 fusion-transfected-Ect1/E6E7 cells subcutaneously into NOG mice generated squamous cell carcinoma xenograft tumors, suggesting the association between FGFR3-TACC3 fusion and squamous cell carcinogenesis. Transfection of a FGFR3-TACC3 fusion transcript into four cervical cancer cell lines (SiHa, ME180, HeLa, and Ca Ski) induced activation of the MAPK pathway and enhancement of cell proliferation. Transcriptome analysis of the FGFR3-TACC3 fusion-transfected cell lines revealed that an IL8-triggered inflammatory response was increased, via activation of FGFR3-MAPK signaling. Continuous expression of FGFR3-TACC3 fusion led to activation of the PI3K-AKT pathway only in the two cell lines that harbored PIK3CA mutations. Sensitivity to the FGFR inhibitor, BGJ398, was found to depend on PIK3CA mutation status. Dual inhibition of both FGFR and AKT showed an obvious synergistic effect in cell lines that harbor mutant PIK3CA. Additionally, TACC3 inhibitor, KHS101, suppressed FGFR3-TACC3 fusion protein expression and showed antitumor effect against FGFR3-TACC3 fusion-transfected cell lines. FGFR3-TACC3 fusion-positive cancer has frequent genetic alterations of the PI3K/AKT pathway and selection of appropriate treatment based on PI3K/AKT pathway status should be required.

Targeting intercellular adhesion molecule-1 prolongs survival in mice bearing bevacizumab-resistant glioblastoma.

Intercellular cell adhesion molecule 1 (ICAM-1; also known as CD54) is overexpressed in bevacizumab-resistant glioblastoma. In the present study, we tested our hypothesis that highly expressed ICAM-1 mediates glioblastoma's resistance to antiangiogenic therapy. We validated ICAM-1 overexpression in tumors resistant to antiangiogenic therapy using real-time polymerase chain reaction, immunohistochemistry, and Western blotting. We also detected ICAM1 expression in most glioma stem cells (GSCs). We investigated the mechanism of ICAM-1 overexpression after bevacizumab treatment and found that ICAM-1 protein expression was markedly increased in a time-dependent manner in GSC11 and GSC17 cells under hypoxic conditions in vitro. We also found that hypoxia induced ICAM-1 overexpression through the up-regulation of phosphorylated signal transducer and activator of transcription (p-STAT3). Hypoxia-induced p-STAT3 increased the mRNA transcription of ICAM-1, which we could inhibit with the STAT3 inhibitor AZD1480. Next, we used GFP-tagged ICAM-1 shRNA lentivirus to knock down ICAM-1 in GSC11 and GSC17 glioma cell lines. Then, we injected shICAM-1 GSC11 and scramble glioma stem cells into the brains of nude mice. Mice bearing tumors from shICAM-1 GSC11 cells survived significantly longer than mice injected with control cells did. The tumor sizes was significantly decreased in mice bearing tumors from shICAM-1 cells than that in mice bearing tumors from GFP-tagged GSC11 control cells. Knocking down ICAM-1 suppressed tumor invasion in vitro and in vivo and inhibited macrophage infiltration to the tumor site in bevacizumab-treated mice. Our findings suggest that ICAM-1 is a potentially important mediator of tumor migration and invasion in bevacizumab-resistant glioblastoma. Targeting ICAM-1 may provide a new strategy for enhancing the efficacy of antiangiogenic therapy against glioblastoma and preventing the invasive phenotype of the disease.

Adolescent Exposure to the Synthetic Cannabinoid WIN 55212-2 Modifies Cocaine Withdrawal Symptoms in Adult Mice.

Chronic cannabinoid consumption is an increasingly common behavior among teenagers and has been shown to cause long-lasting neurobehavioral alterations. Besides, it has been demonstrated that cocaine addiction in adulthood is highly correlated with cannabis abuse during adolescence. Cocaine consumption and subsequent abstinence from it can cause psychiatric symptoms, such as psychosis, cognitive impairment, anxiety, and depression. The aim of the present research was to study the consequences of adolescent exposure to cannabis on the psychiatric-like effects promoted by cocaine withdrawal in adult mice. We pre-treated juvenile mice with the cannabinoid CB1 receptor agonist WIN 55212-2 (WIN) and then subjected them to a chronic cocaine treatment during adulthood. Following these treatments, animals were tested under cocaine withdrawal in the following paradigms: pre-pulse inhibition, object recognition, elevated plus maze, and tail suspension. The long-term psychotic-like actions induced by WIN were not modified after cocaine cessation. Moreover, the memory impairments induced by cocaine withdrawal were not altered by previous adolescent WIN intake. However, WIN pre-treatment prevented the anxiogenic effects observed after cocaine abstinence, and led to greater depressive-like symptoms following cocaine removal in adulthood. This study is the first to show the long-lasting behavioral consequences of juvenile exposure to WIN on cocaine withdrawal in adult mice.