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Fuel ethanol production from lignocellulosic materials is at a level where commercial biofuel production is becoming a reality. The solubilization of the hemicellulose fraction in lignocellulosic-based feedstocks results in a large variety of sugar mixtures including xylose. However, allowing xylose fermentation in yeast that normally is used for fuel ethanol production requires genetic engineering. Moreover, the efficiency of lignocellulosic pretreatment, together with the release and generation of inhibitory compounds in this step, are some of the new challenges faced during second generation ethanol production. Successful advances in all these aspects will improve ethanol yield, productivity and titer, which will reduce the impact on capital and operating costs, leading to the consolidation of the fermentation of lignocellulosic biomass as an economically feasible option for the production of renewable fuels. Therefore the development of yeast strains capable of fermenting a wide variety of sugars in a highly inhibitory environment, while maintaining a high ethanol yield and production rate, is required. This review provides an overview of the current status in the use of xylose-engineered yeast strains and describes the remaining challenges to achieve an efficient deployment of lignocellulosic-based ethanol production.

Potentiating anti-tumor immunity by inducing tumor inflammation and T cell-mediated responses are a promising area of cancer therapy. Immunomodulatory agents that promote these effects function via a wide variety of mechanisms, including upregulation of antigen presentation pathways. Here, we show that major histocompatibility class-I (MHC-I) genes are methylated in human breast cancers, suppressing their expression. Treatment of breast cancer cell lines with a next-generation hypomethylating agent, guadecitabine, upregulates MHC-I expression in response to interferon-γ. In murine tumor models of breast cancer, guadecitabine upregulates MHC-I in tumor cells promoting recruitment of CD8+ T cells to the microenvironment. Finally, we show that MHC-I genes are upregulated in breast cancer patients treated with hypomethylating agents. Thus, the immunomodulatory effects of hypomethylating agents likely involve upregulation of class-I antigen presentation to potentiate CD8+ T cell responses. These strategies may be useful to potentiate anti-tumor immunity and responses to checkpoint inhibition in immune-refractory breast cancers. Immunotherapy often fails as a single option treatment in cancer. Here, the authors show that targeting of DNA methyltransferases, such as DNMT1, can potentiate anti-tumor immunity and response to checkpoint inhibition by increasing MHC gene expression and the recruitment of CD8+ T cells.

The high potential of siRNAs to silence oncogenic drivers remains largely untapped due to the challenges of tumor cell delivery. Here, divalent lipid-conjugated siRNAs are optimized for in situ binding to albumin to improve pharmacokinetics and tumor delivery. Systematic variation of the siRNA conjugate structure reveals that the location of the linker branching site dictates tendency toward albumin association versus self-assembly, while the lipid hydrophobicity and reversibility of albumin binding also contribute to siRNA intracellular delivery. The lead structure increases tumor siRNA accumulation 12-fold in orthotopic triple negative breast cancer (TNBC) tumors over the parent siRNA. This structure achieves approximately 80% silencing of the anti-apoptotic oncogene MCL1 and yields better survival outcomes in three TNBC models than an MCL-1 small molecule inhibitor. These studies provide new structure-function insights on siRNA-lipid conjugate structures that are intravenously injected, associate in situ with serum albumin, and improve pharmacokinetics and tumor treatment efficacy. Limited tumor cell delivery is a major challenge for the efficacious delivery of siRNAs to silence traditionally undruggable oncogenes. Here the authors optimize siRNAs for in situ binding to albumin through C18 lipid modifications and show the application of the lead conjugate structure for targeting MCL1 in orthotopic breast tumors in mice.

Anti-PD-1 therapy yields objective clinical responses in 30–40% of advanced melanoma patients. Since most patients do not respond, predictive biomarkers to guide treatment selection are needed. We hypothesize that MHC-I/II expression is required for tumour antigen presentation and may predict anti-PD-1 therapy response. In this study, across 60 melanoma cell lines, we find bimodal expression patterns of MHC-II, while MHC-I expression was ubiquitous. A unique subset of melanomas are capable of expressing MHC-II under basal or IFNγ-stimulated conditions. Using pathway analysis, we show that MHC-II(+) cell lines demonstrate signatures of ‘PD-1 signalling’, ‘allograft rejection’ and ‘T-cell receptor signalling’, among others. In two independent cohorts of anti-PD-1-treated melanoma patients, MHC-II positivity on tumour cells is associated with therapeutic response, progression-free and overall survival, as well as CD4 + and CD8 + tumour infiltrate. MHC-II + tumours can be identified by melanoma-specific immunohistochemistry using commercially available antibodies for HLA-DR to improve anti-PD-1 patient selection. Immunotherapy is used to treat melanoma, however patient responses vary widely highlighting the need for factors that can predict therapeutic success. Here, the authors show that MHC-II molecules expressed by tumour cells are positively correlated with a good response to therapy and overall patient survival.

Triggering receptor expressed on myeloid cells 2 (TREM2) has been shown to confer immunosuppressive effects when expressed on tumor associated macrophages and thus has become a prominent focus of cancer research in recent years. The primary aims of this study were to explore the distribution of TREM2-expressing macrophages in early-stage ER+ breast cancer, specifically asking if there is a correlation with tumor aggressiveness and/or metabolic syndrome. To address these aims, we performed immunofluorescent staining for TREM2, CD68, and DAPI in 95 early-stage breast cancer samples from patients who underwent surgery at Vanderbilt University Medical Center. We assessed associations between TREM2 + CD68 + cell density in three distinct regions of the tumor and multiple tumor characteristics, prognostic factors, and metabolic syndrome criteria. Although some analyses, including associations with menopausal status, hormone receptor expression, and histological subtype, reached statistical significance, the overall data revealed no significant associations between TREM2-expressing macrophages and tumor prognostic factors or metabolic syndrome criteria in early-stage ER+ breast cancer. Consequently, our results indicate that TREM2 likely does not serve as a reliable biomarker for ER+ breast cancer. However, TREM2 may still hold prognostic value in other subtypes such as triple negative breast cancer.

Akt phosphorylation is a major driver of cell survival, motility, and proliferation in development and disease, causing increased interest in upstream regulators of Akt like mTOR complex 2 (mTORC2). We used genetic disruption of Rictor to impair mTORC2 activity in mouse mammary epithelia, which decreased Akt phosphorylation, ductal length, secondary branching, cell motility, and cell survival. These effects were recapitulated with a pharmacological dual inhibitor of mTORC1/mTORC2, but not upon genetic disruption of mTORC1 function via Raptor deletion. Surprisingly, Akt re-activation was not sufficient to rescue cell survival or invasion, and modestly increased branching of mTORC2-impaired mammary epithelial cells (MECs) in culture and in vivo. However, another mTORC2 substrate, protein kinase C (PKC)-alpha, fully rescued mTORC2-impaired MEC branching, invasion, and survival, as well as branching morphogenesis in vivo. PKC-alpha-mediated signaling through the small GTPase Rac1 was necessary for mTORC2-dependent mammary epithelial development during puberty, revealing a novel role for Rictor/mTORC2 in MEC survival and motility during branching morphogenesis through a PKC-alpha/Rac1-dependent mechanism.

AimsMicro-organisms are present on the skin surface of patients, staff and the immediate patient environment which can result in contamination of blood cultures. Contamination can lead to inappropriate treatment, prolonged hospital stay, increased cost (estimated: £5000/contaminated culture), family and patient inconvenience and it affect mandatory surveillance data and protocols.The aim of this audit is to assess the occurrence of contaminated blood cultures over a 4 month period in the paediatrics department of a DGH, to identify any areas for improvement and recommend interventions to decrease contamination. This will be achieved by emphasising the importance of ANTT (Aseptic Non-Touch Technique) and by creating a blood culture pack as a quality improvement project.The blood culture pack will include all the required equipment to facilitate correct ANTT and a procedure sticker will be added to the microbiology form to prompt the individual taking the blood culture to apply ANTT and complete the required documentation upon taking a blood culture.MethodsA retrospective review of the electronic health records of paediatric patients, who had a positive blood culture over a 4 month period then identify those with pathogens who are most likely contamination – related. Results compared against key performance indicator of blood culture contamination in adult of <3%)ResultsTotal number of blood culture done in this period was 306, 15 (4.9%) cultures were positive of which 3% (n=9) were identified as contaminated based on the pathogen isolated.Abstract 67 Figure 1Abstract 67 Table 1Risk factors identified were the location in the hospital where blood culture was taken with cultures coming from the postnatal ward being the most likely to have contaminated culture ( n=5 (1.7%); followed by blood cultures in paediatric A&E and paediatric ward (n=4(1.3%). Main challenges identified were lack of universal approach to the procedure of taking blood culture and difficulty identifying the location and the person responsible for the procedure.ConclusionContaminated blood culture leads to prolonged hospital stay and increased cost. Simple intervention can improve ANTT practice and ensure universal approach and complete documentation. Re-audit is required to measure the effect of these interventions on the occurrence of contaminated blood culture.

ObjectiveBicuspid aortic valve (BAV) is the most common congenital heart disease. This study aimed to determine the prevalence rate of BAV in first-degree relatives (FDR) and the inheritance pattern according to different morphotypes and aortic dilation.MethodsBAV probands were consecutively studied at eight tertiary referral centres. After sequential screening, FDR were included in the study. The BAV morphotype, aortic dilation and aortic phenotype were assessed by transthoracic echocardiography.ResultsSeven hundred and twenty-four FDR of 256 BAV probands agreed to undergo family screening. The prevalence of BAV was 6.4% in FDR (9.2% in men, 3.5% in women, p=0.002). Aortic dilation was diagnosed in 9.6% of FRD with tricuspid aortic valves (TAV), with a root phenotype in 2.7% and tubular in 6.9% and more frequently in the presence of arterial hypertension (OR 4.48; CI 95% 2.51 to 7.99; p=0.0001) and valvular regurgitation (OR 5.87, CI 95% 1.37 to 25.16; p=0.025). The heritability (h2 ) of BAV was highly significant (0.47; p=0.002); however, no concordance was observed among valve morphotypes. Aortic dilation heritability was not significant.ConclusionsThe BAV prevalence rate in FDR was low (6.4%) but aortic dilation was observed in 9.6% of FDR with TAV. The heritability of BAV was high without concordance in valve morphotypes, and aortic dilation heritability was not observed. Patients with BAV should be made aware of its familial pattern.

Background The importance of the mTOR complex 2 (mTORC2) signaling complex in tumor progression is becoming increasingly recognized. HER2- amplified breast cancers use Rictor/mTORC2 signaling to drive tumor formation, tumor cell survival and resistance to human epidermal growth factor receptor 2 (HER2)-targeted therapy. Cell motility, a key step in the metastatic process, can be activated by mTORC2 in luminal and triple negative breast cancer cell lines, but its role in promoting metastases from HER2- amplified breast cancers is not yet clear. Methods Because Rictor is an obligate cofactor of mTORC2, we genetically engineered Rictor ablation or overexpression in mouse and human HER2 -amplified breast cancer models for modulation of mTORC2 activity. Signaling through mTORC2-dependent pathways was also manipulated using pharmacological inhibitors of mTOR, Akt, and Rac. Signaling was assessed by western analysis and biochemical pull-down assays specific for Rac-GTP and for active Rac guanine nucleotide exchange factors (GEFs). Metastases were assessed from spontaneous tumors and from intravenously delivered tumor cells. Motility and invasion of cells was assessed using Matrigel-coated transwell assays. Results We found that Rictor ablation potently impaired, while Rictor overexpression increased, metastasis in spontaneous and intravenously seeded models of HER2-overexpressing breast cancers. Additionally, migration and invasion of HER2 -amplified human breast cancer cells was diminished in the absence of Rictor, or upon pharmacological mTOR kinase inhibition. Active Rac1 was required for Rictor-dependent invasion and motility, which rescued invasion/motility in Rictor depleted cells. Rictor/mTORC2-dependent dampening of the endogenous Rac1 inhibitor RhoGDI2, a factor that correlated directly with increased overall survival in HER2 -amplified breast cancer patients, promoted Rac1 activity and tumor cell invasion/migration. The mTORC2 substrate Akt did not affect RhoGDI2 dampening, but partially increased Rac1 activity through the Rac-GEF Tiam1, thus partially rescuing cell invasion/motility. The mTORC2 effector protein kinase C (PKC)α did rescue Rictor-mediated RhoGDI2 downregulation, partially rescuing Rac-guanosine triphosphate (GTP) and migration/motility. Conclusion These findings suggest that mTORC2 uses two coordinated pathways to activate cell invasion/motility, both of which converge on Rac1. Akt signaling activates Rac1 through the Rac-GEF Tiam1, while PKC signaling dampens expression of the endogenous Rac1 inhibitor, RhoGDI2.

p73 and p63 are members of the p53 family that exhibit overlapping and distinct functions in development and homeostasis. The evaluation of p73 and p63 isoform expression across human tissue can provide greater insight to the functional interactions between family members. We determined the mRNA isoform expression patterns of TP73 and TP63 across a panel of 36 human tissues and protein expression within the highest-expressing tissues. TP73 and TP63 expression significantly correlated across tissues. In tissues with concurrent mRNA expression, nuclear co-expression of both proteins was observed in a majority of cells. Using GTEx data, we quantified p73 and p63 isoform expression in human tissue and identified that the α-isoforms of TP73 and TP63 were the predominant isoform expressed in nearly all tissues. Further, we identified a previously unreported p73 mRNA product encoded by exons 4 to 14. In sum, these data provide the most comprehensive tissue-specific atlas of p73 and p63 protein and mRNA expression patterns in human and murine samples, indicating coordinate expression of these transcription factors in the majority of tissues in which they are expressed.