Abstract Cancer cells depend on nicotinamide adenine dinucleotide phosphate (NADPH) to combat oxidative stress and support reductive biosynthesis. One major NADPH production route is the oxidative ...pentose phosphate pathway (committed step: glucose-6-phosphate dehydrogenase, G6PD). Alternatives exist and can compensate in some tumors. Here, using genetically-engineered lung cancer mouse models, we show that G6PD ablation significantly suppresses Kras G12D/+ ;Lkb1 -/- (KL) but not Kras G12D/+ ;P53 -/- (KP) lung tumorigenesis. In vivo isotope tracing and metabolomics reveal that G6PD ablation significantly impairs NADPH generation, redox balance, and de novo lipogenesis in KL but not KP lung tumors. Mechanistically, in KL tumors, G6PD ablation activates p53, suppressing tumor growth. As tumors progress, G6PD-deficient KL tumors increase an alternative NADPH source from serine-driven one carbon metabolism, rendering associated tumor-derived cell lines sensitive to serine/glycine depletion. Thus, oncogenic driver mutations determine lung cancer dependence on G6PD, whose targeting is a potential therapeutic strategy for tumors harboring KRAS and LKB1 co-mutations.
To overcome the hurdles of immunotherapy, we investigated whether calcipotriol, a synthetic vitamin D analog, could overcome the immune evasion of glioblastoma multiforme (GBM) by modulating immune ...responses and the immunosuppressive tumor microenvironment. Administration of calcipotriol considerably reduced tumor growth. Both in vivo and in vitro studies revealed that CD8+T and natural killer (NK) cell gene signatures were enriched and activated, producing high levels of IFN-γ and granzyme B. In contrast, regulatory T cells (Treg) were significantly reduced in the calcipotriol-treated group. The expression of CD127, the receptor for thymic stromal lymphopoietin (TSLP), is elevated in CD4+T cells and potentially supports T-cell priming. Depleting CD4+T cells, but not NK or CD8+T cells, completely abrogated the antitumor efficacy of calcipotriol. These data highlight that the calcipotriol/TSLP/CD4+T axis can activate CD8+T and NK cells with a concomitant reduction in the number of Tregs in GBM. Therefore, calcipotriol can be a novel therapeutic modality to overcome the immune resistance of GBM by converting immunologically “cold” tumors into “hot” tumors.
Data are available upon reasonable request. The RNA-seq dataset comparing the transcriptomes of control and calcipotriol-treated GL261 tumors is available from the corresponding author upon request.
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Intraoperative real-time confocal laser endomicroscopy (CLE) is an alternative modality for frozen tissue histology that enables visualization of the cytoarchitecture of living tissues with spatial ...resolution at the cellular level. We developed a new CLE with a "Lissajous scanning pattern" and conducted a study to identify its feasibility for fluorescence-guided brain tumor diagnosis.
Conventional hematoxylin and eosin (H&E) histological images were compared with indocyanine green (ICG)-enhanced CLE images in two settings (1): experimental study with in vitro tumor cells and ex vivo glial tumors of mice, and (2) clinical evaluation with surgically resected human brain tumors. First, CLE images were obtained from cultured U87 and GL261 glioma cells. Then, U87 and GL261 tumor cells were implanted into the mouse brain, and H&E staining was compared with CLE images of normal and tumor tissues
. To determine the invasion of the normal brain, two types of patient-derived glioma cells (CSC2 and X01) were used for orthotopic intracranial tumor formation and compared using two methods (CLE vs. H&E staining). Second, in human brain tumors, tissue specimens from 69 patients were prospectively obtained after elective surgical resection and were also compared using two methods, namely, CLE and H&E staining. The comparison was performed by an experienced neuropathologist.
When ICG was incubated
, U87 and GL261 cell morphologies were well-defined in the CLE images and depended on dimethyl sulfoxide.
examination of xenograft glioma tissues revealed dense and heterogeneous glioma cell cores and peritumoral necrosis using both methods. CLE images also detected invasive tumor cell clusters in the normal brain of the patient-derived glioma xenograft model, which corresponded to H&E staining. In human tissue specimens, CLE images effectively visualized the cytoarchitecture of the normal brain and tumors. In addition, pathognomonic microstructures according to tumor subtype were also clearly observed. Interestingly, in gliomas, the cellularity of the tumor and the density of streak-like patterns were significantly associated with tumor grade in the CLE images. Finally, panoramic view reconstruction was successfully conducted for visualizing a gross tissue morphology.
In conclusion, the newly developed CLE with Lissajous laser scanning can be a helpful intraoperative device for the diagnosis, detection of tumor-free margins, and maximal safe resection of brain tumors.
Extra-domain B of fibronectin (EDB-FN) is an alternatively spliced form of fibronectin with high expression in the extracellular matrix of neovascularized tissues and malignant cancer cells. In this ...study, we evaluated the practicality of using EDB-FN as a biomarker and therapeutic target for malignant gliomas (MGs), representative intractable diseases involving brain tumors.
The microarray- and sequence-based patient transcriptomic database 'Oncopression' and tissue microarray of MG patient tissue samples were analyzed. EDB-FN data were extracted and evaluated from 23,344 patient samples of 17 types of cancer to assess its effectiveness and selectivity as a molecular target. To strengthen the results of the patient data analysis, the utility of EDB-FN as a molecular marker and target for MG was verified using active EDB-FN-targeting ultrasmall lipidic micellar nanoparticles (~12 nm), which had a high drug-loading capacity and were efficiently internalized by MG cells
and
.
Brain tumors had a 1.42-fold cancer-to-normal ratio (
< 0.0001), the second highest among 17 cancers after head and neck cancer. Patient tissue microarray analysis showed that the EDB-FN high-expression group had a 5.5-fold higher risk of progression than the EDB-FN low-expression group (
< 0.03). By labeling docetaxel-containing ultrasmall micelles with a bipodal aptide targeting EDB-FN (termed APT
-DSPE-DTX), we generated micelles that could specifically bind to MG cells, leading to superior antitumor efficacy of EDB-FN-targeting nanoparticles compared to nontargeting controls.
Taken together, these results show that EDB-FN can be an effective drug delivery target and biomarker for MG.
Glioblastoma multiforme (GBM) is known as one of the most fatal forms of cancer. MicroRNAs have been widely implicated in the regulation of mammalian development and pathogenesis. The brain-enriched ...miR-29 subfamilies are known to be exclusively expressed in the developing brain, and they are aberrantly down-regulated in GBM. This study aims to elucidate the role of miR-29b in GBM development and the feasibility of therapeutic targeting using conjugated nanoparticles.
After confirmation of miR-29b expression levels in GBM tissues by analysis of open source data, the anticancer effect of miR-29b was tested by the introduction of syn-hsa-miR-29b-3p in the A172 GBM cell line. In vitro studies of cell viability and apoptosis and ex vivo study using GBM tissue slice cultures from 3 patients and nanoparticle delivery of miR-29b were performed.
We discovered an increase in apoptotic cell populations with the introduction of miR-29b in the GBM cell line. An established human-derived GBM tissue slice culture system confirmed the anticancer effect of miR-29b-conjugated nanoparticles. Using PCR array, we found that exogenous miR-29b inhibits the expression of COL1A2, COL3A1, COL4A1, ELN, ITGA11, MMP24, and SPARC, which mediates an anticancer effect.
miR-29b may serve as a putative therapeutic molecule when its expression is restored using a nanoparticle delivery system in GBM.
Despite the presence of aggressive treatment strategies, glioblastoma remains intractable, warranting a novel therapeutic modality. An oral antipsychotic agent, penflurido (PFD), used for ...schizophrenia treatment, has shown an antitumor effect on various types of cancer cells. As glioma sphere-forming cells (GSCs) are known to mediate drug resistance in glioblastoma, and considering that antipsychotics can easily penetrate the blood-brain barrier, we investigated the antitumor effect of PFD on patient-derived GSCs. Using five GSCs, we found that PFD exerts an antiproliferative effect in a time- and dose-dependent manner. At IC50, spheroid size and second-generation spheroid formation were significantly suppressed. Stemness factors, SOX2 and OCT4, were decreased. PFD treatment reduced cancer cell migration and invasion by reducing the Integrin α6 and uPAR levels and suppression of the expression of epithelial-to-mesenchymal transition (EMT) factors, vimentin and Zeb1. GLI1 was found to be involved in PFD-induced EMT inhibition. Furthermore, combinatorial treatment of PFD with temozolomide (TMZ) significantly suppressed tumor growth and prolonged survival in vivo. Immunostaining revealed decreased expression of GLI1, SOX2, and vimentin in the PFD treatment group but not in the TMZ-only treatment group. Therefore, PFD can be effectively repurposed for the treatment of glioblastoma by combining it with TMZ.
Context
Despite the growing use of virtual patients (VPs) in medical education, few studies have explored the features and effectiveness of VP‐based medical communication skills training. We ...undertook a systematic review to summarise the design and evaluation of VP‐based medical communication skills training systems in order to identify features of successful cases.
Methods
Following PRISMA guidelines, we searched four databases for studies published between 2006 and 2018. Using a refined classification scheme, we extracted data on instructional design (scenario and instructional intervention), technological design (modality and interaction), and evaluation (user experience, learning effectiveness and evaluator). We assessed the quality of studies using the Medical Education Research Study Quality Instrument (MERSQI) and the QualSyst standard assessment criteria.
Results
A total of 14 studies were included for review. Of these, 85.7% (n = 12) were quantitative and 71.4% (n = 10) involved undergraduate students. The most common VP training scenario was history taking followed by the delivery of bad news. Diverse instructional interventions, including tutorials, learning activities, and feedback, were embedded in the VPs. The first‐person perspective animated within‐screen size VP was a popular technological feature. Most evaluations concerned the reality of simulation (for user experience) and skill in expressing empathy (as a learning outcome). Of the eight comparative studies, half reported significant attitude or skill improvements in the VP group. The distinct features of VPs shown to be effective were well‐designed instructional interventions (eg, a pre‐activity with a protocol‐informed tutorial), and post‐activity (eg, debrief or reflection), scaffolding and human feedback, but not system feedback.
Conclusions
Evidence‐based VP training can enable students to gain communication skills in a safe and affordable learning environment. Elaborate technology alone cannot guarantee effective learning, but evidence‐based instructional interventions can facilitate its optimal use and bring about better learning outcomes.
This review of the design and evaluation of virtual patient‐based medical communication training illustrates that sound pedagogical elements have a more substantial impact than technological elements.
Abstract
Tetraspanin 12 (TSPAN12), a member of the tetraspanin family that are increasingly known to be involved in various mechanisms of tumor progression, mediates various cellular signaling ...processes in cancer cells. With respect to the brain, previous studies have shown that TSPAN12 is related with the maturation of a membrane-associated metalloproteinase 10 and the production of amyloid β plaque, but there are no studies related to brain tumors to date. Therefore, we designed this study to investigate the role of TSPAN 12 on malignant glioma (MG) cells and patients. TSPAN12 silencing in MG cells significantly progressed cell proliferation, migration and invasion capacities, and extracellular matrix adhesion ability as well as stem cell properties, in vitro. Mechanistically, we identified that FAK and ERK signaling were involved in MG cells with TSPAN12 expression. Moreover, clinical analysis of MG patient tissues microarray showed that the expression level of TSPAN12 was negatively correlated with the prognosis in MG patients. Collectively, more studies are needed, but we suggest that TSPAN12 can be used as an alternative biomarker to predict the prognosis of MG patient and help develop MG treatment strategies.
Tooth-brushing is one of the most important health behaviors to teach children considering potentially serious ramifications of poor dental health. However, children's tooth-brushing behavior is ...affected by various developmental factors. The aim of this cross-sectional study was to investigate factors related to the tooth-brushing behavior of children adopting the Theory of Planned Behavior. A preliminary elicitation study with 33 primary school students identified underlying beliefs related to tooth-brushing intentions. This data was analysed, synthesized, and incorporated into the development of survey items for three age-appropriate, closed-ended questionnaires administered to 709 primary public school students. Path analyses using structural equation modelling were used to discover the structural relationships among the direct and indirect determinants of tooth-brushing behaviors, and path estimates and the model fit were calculated. Social recognition, peer influence, self-motivating strategies, and cognitive aspects of tooth-brushing were found to become more influential in facilitating behavioral intention with age. In the path models, the tooth-brushing behavioral intention was significantly related to perceived behavioral control rather than behavioral beliefs and normative beliefs. Subjective norms were found to become more significant as children matured. This result suggests that education to improve children's tooth-brushing behavior needs be appropriate to the developmental stage of children.
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