Revisiting astrocyte to neuron conversion with lineage tracing in vivo.

In vivo cell fate conversions have emerged as potential regeneration-based therapeutics for injury and disease. Recent studies reported that ectopic expression or knockdown of certain factors can convert resident astrocytes into functional neurons with high efficiency, region specificity, and precise connectivity. However, using stringent lineage tracing in the mouse brain, we show that the presumed astrocyte-converted neurons are actually endogenous neurons. AAV-mediated co-expression of NEUROD1 and a reporter specifically and efficiently induces reporter-labeled neurons. However, these neurons cannot be traced retrospectively to quiescent or reactive astrocytes using lineage-mapping strategies. Instead, through a retrograde labeling approach, our results reveal that endogenous neurons are the source for these viral-reporter-labeled neurons. Similarly, despite efficient knockdown of PTBP1 in vivo, genetically traced resident astrocytes were not converted into neurons. Together, our results highlight the requirement of lineage-tracing strategies, which should be broadly applied to studies of cell fate conversions in vivo.

Cooperative Cu/Pd-Catalyzed 1,5-Boroacylation of Cyclopropyl-Substituted Alkylidenecyclopropanes.

A Cu/Pd-cocatalyzed 1,5-boroacylation of cyclopropyl-substituted ACPs with B2pin2 and acid chlorides has been developed. Using cyclopropyl-substituted ACPs as the starting material, a broad range of 1,5-boroacylated products with multiple functional groups was prepared in good yields with excellent regio- and stereoselectively. Both aromatic and aliphatic acid chlorides were tolerated in this reaction.

CiTSA: a comprehensive platform provides experimentally supported signatures of cancer immunotherapy and analysis tools based on bulk and scRNA-seq data.

Immunotherapy has greatly changed the status of cancer treatment, and many patients do not respond or develop acquired resistance. The related research is blocked by lacking of comprehensive resources for researchers to discovery and analysis signatures, then further exploring the mechanisms. Here, we first offered a benchmarking dataset of experimentally supported signatures of cancer immunotherapy by manually curated from published literature works and provided an overview. We then developed CiTSA ( http://bio-bigdata.hrbmu.edu.cn/CiTSA/ ) which stores 878 entries of experimentally supported associations between 412 signatures such as genes, cells, and immunotherapy across 30 cancer types. CiTSA also provides flexible online tools to identify and visualize molecular/cell feature and interaction, to perform function, correlation, and survival analysis, and to execute cell clustering, cluster activity, and cell-cell communication analysis based on single cell and bulk datasets of cancer immunotherapy. In summary, we provided an overview of experimentally supported cancer immunotherapy signatures and developed CiTSA which is a comprehensive and high-quality resource and is helpful for understanding the mechanism of cancer immunity and immunotherapy, developing novel therapeutic targets and promoting precision immunotherapy for cancer.

Dynamic Alterations to Hepatic MicroRNA-29a in Response to Long-Term High-Fat Diet and EtOH Feeding.

MicroRNA-29a (miR-29a) is a well characterized fibro-inflammatory molecule and its aberrant expression is linked to a variety of pathological liver conditions. The long-term effects of a high-fat diet (HFD) in combination with different levels of EtOH consumption on miR-29a expression and liver pathobiology are unknown. Mice at 8 weeks of age were divided into five groups (calorie-matched diet plus water (CMD) as a control group, HFD plus water (HFD) as a liver disease group, HFD plus 2% EtOH (HFD + 2% E), HFD + 10% E, and HFD + 20% E as intervention groups) and fed for 4, 13, 26, or 39 weeks. At each time point, analyses were performed for liver weight/body weight (BW) ratio, AST/ALT ratio, as well as liver histology assessments, which included inflammation, estimated fat deposition, lipid area, and fibrosis. Hepatic miR-29a was measured and correlations with phenotypic traits were determined. Four-week feeding produced no differences between the groups on all collected phenotypic traits or miR-29a expression, while significant effects were observed after 13 weeks, with EtOH concentration-specific induction of miR-29a. A turning point for most of the collected traits was apparent at 26 weeks, and miR-29a was significantly down-regulated with increasing liver injury. Overall, miR-29a up-regulation was associated with a lower liver/BW ratio, fat deposition, inflammation, and fibrosis, suggesting a protective role of miR-29a against liver disease progression. A HFD plus increasing concentrations of EtOH produces progressive adverse effects on the liver, with no evidence of beneficial effects of low-dose EtOH consumption. Moreover, miR-29a up-regulation is associated with less severe liver injury.

NEK6 is an injury-responsive kinase cooperating with STAT3 in regulation of reactive astrogliosis.

In response to brain injury, resident astrocytes become reactive and play dynamic roles in neural repair and regeneration. The signaling pathways underlying such reactive astrogliosis remain largely unclear. We here show that NEK6, a NIMA-related serine/threonine protein kinase, is rapidly induced following pathological stimulations and plays critical roles in reactive astrogliosis. Enhanced NEK6 expression promotes reactive astrogliosis and exacerbates brain lesions; and conversely, NEK6 downregulation dampens injury-induced astrocyte reactivity and reduces lesion size. Mechanistically, NEK6 associates with and phosphorylates STAT3. Kinase activity of NEK6 is required for induction of GFAP and PCNA, markers of reactive astrogliosis. Interestingly, NEK6 is also localized in the nucleus and binds to STAT3-responsive genomic elements in astrocytes. These results indicate that NEK6 constitutes a molecular target for the regulation of reactive astrogliosis.

Comprehensive analysis of ncRNA involvement in brain microglia immunology.

Microglia is a major class of brain-resident myeloid cells and non-coding RNAs (ncRNAs) serves as key regulators in microglia homeostasis and inflammatory process. Here, we constructed the systematical association between microglia and ncRNAs including miRNAs, lncRNAs and circRNAs from two aspects, manual retrieval and computational detection. A total of 648 experimental verified ncRNA-microglia associations were obtained from published studies, including ncRNA regulatory patterns within different experimental models. Furthermore, we extracted 9 miRNA and 1 lncRNA expression profiles from the GEO database. Also, we obtained 31 sample-match miRNA and mRNA expression profiles, containing a total of 2335 normal or disordered brain samples. Finally, we developed a platform named MG-ncRexplorer (http://bio-bigdata.hrbmu.edu.cn/MG-ncRexplorer/), exploring the associations between ncRNAs and microglia among experimental validated and computational detection. To demonstrate the usage of MG-ncRexplorer, we constructed regulatory target networks based on manual retrieval associations and identified risk glioma miRNAs among multiple high-throughput expression profiles.

Comprehensive analysis of microglia gene and subpathway signatures for glioma prognosis and drug screening: linking microglia to glioma.

Glioma is the most common malignant tumors in the brain. Previous studies have revealed that, as the innate immune cells in nervous system, microglia cells were involved in glioma pathology. And, the resident microglia displayed its specific biological roles which distinguished with peripheral macrophages. In this study, an integrated analysis was performed based on public resource database to explore specific biological of microglia within glioma. Through comprehensive analysis, the biological characterization underlying two conditions, glioma microglia compared to glioma macrophage (MicT/MacT) as well as glioma microglia compared to normal microglia (MicT/MicN), were revealed. Notably, nine core MicT/MicN genes displayed closely associations with glioma recurrence and prognosis, such as P2RY2, which was analyzed in more than 2800 glioma samples from 25 studies. Furthermore, we applied a random walk based strategy to identify microglia specific subpathways and developed SubP28 signature for glioma prognostic analysis. Multiple validation data sets confirmed the predictive performance of SubP28 and involvement in molecular subtypes. The associations between SuP28 score and microglia M1/M2 polarization were also explored for both GBM and LGG types. Finally, a comprehensive drug-subpathway network was established for screening candidate medicable molecules (drugs) and identifying therapeutic subpathway targets. In conclusions, the comprehensive analysis of microglia related gene and functional signatures in glioma pathobiologic events by large-scale data sets displayed a framework to dissect inner connection between microglia and glioma, and identify robust signature for glioma clinical implications.

Exogenous Oncostatin M induces Cardiac Dysfunction, Musculoskeletal Atrophy, and Fibrosis.

Musculoskeletal diseases such as muscular dystrophy, cachexia, osteoarthritis, and rheumatoid arthritis impair overall physical health and reduce survival. Patients suffer from pain, dysfunction, and dysmobility due to inflammation and fibrosis in bones, muscles, and joints, both locally and systemically. The Interleukin-6 (IL-6) family of cytokines, most notably IL-6, is implicated in musculoskeletal disorders and cachexia. Here we show elevated circulating levels of OSM in murine pancreatic cancer cachexia and evaluate the effects of the IL-6 family member, Oncostatin M (OSM), on muscle and bone using adeno-associated virus (AAV) mediated over-expression of murine OSM in wildtype and IL-6 deficient mice. Initial studies with high titer AAV-OSM injection yielded high circulating OSM and IL-6, thrombocytosis, inflammation, and 60% mortality without muscle loss within 4 days. Subsequently, to mimic OSM levels in cachexia, a lower titer of AAV-OSM was used in wildtype and Il6 null mice, observing effects out to 4 weeks and 12 weeks. AAV-OSM caused muscle atrophy and fibrosis in the gastrocnemius, tibialis anterior, and quadriceps of the injected limb, but these effects were not observed on the non-injected side. In contrast, OSM induced both local and distant trabecular bone loss as shown by reduced bone volume, trabecular number, and thickness, and increased trabecular separation. OSM caused cardiac dysfunction including reduced ejection fraction and reduced fractional shortening. RNA-sequencing of cardiac muscle revealed upregulation of genes related to inflammation and fibrosis. None of these effects were different in IL-6 knockout mice. Thus, OSM induces local muscle atrophy, systemic bone loss, tissue fibrosis, and cardiac dysfunction independently of IL-6, suggesting a role for OSM in musculoskeletal conditions with these characteristics, including cancer cachexia.

Novel PSEN1 and PSEN2 Mutations Identified in Sporadic Early-onset Alzheimer Disease and Posterior Cortical Atrophy.

BACKGROUND/PURPOSE: Sporadic early-onset Alzheimer disease (sEOAD) and its visual variant, posterior cortical atrophy (PCA), have a disease onset at less than 65 years of age with no familial aggregation. The etiology and genetic basis of these diseases remain poorly understood. Our study aimed to identify additional mutations or variants associated with sEOAD and PCA and to further examine their genetic and phenotypic spectrums. METHODS: We performed whole-exome sequencing and analyzed the clinical and neuroimaging features of mutation carriers with 29 patients having sEOAD and 25 having PCA. RESULTS: Nine rare damaging variants were identified in 4 patients with sEOAD and 3 with PCA. A novel mutation (p.A136V) in PSEN1 was identified in a patient with sEOAD and a likely pathogenic variant (p.M239T) was identified for PSEN2 in a patient with PCA. In addition, 7 rare damaging variants were detected in other genes related to neurodegenerative diseases. The patient carrying the PSEN1 p.A136V mutation presented with typical clinical and imaging features of sEOAD, and the PCA patient with the PSEN2 p.M239T mutation presented with visuospatial impairment as the initial symptom. CONCLUSION: Our study expands the PSEN1 mutation spectrum of sEOAD and highlights the importance of screening PSEN1 and/or PSEN2 mutations in PCA patients.

Associations of the neutrophil to lymphocyte ratio with intracranial artery stenosis and ischemic stroke.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) has emerged as an inflammatory marker. However, the associations of NLR with intracranial artery stenosis (ICAS) and ischemic stroke remain unclear. This study aimed to examine the associations of NLR with ICAS and ischemic stroke among a large and high-risk population. METHODS: Participants with records of clinical characteristics were prospectively recruited from the Neurology Department and Health & Physical Examination Center of Qingdao Municipal Hospital. Logistic regression analysis was used to examine the associations of NLR with ICAS and ischemic stroke. Moreover, we also conducted parametric mediation analysis to estimate the effect of NLR on the risk of ischemic stroke mediated through ICAS. RESULTS: A total of 2989 participants were enrolled in this study. After adjusting for covariates, NLR (OR = 1.125, 95%CI 1.070-1.183) and ICAS (OR = 1.638, 95%CI 1.364-1.967) were significantly associated with ischemic stroke. Compared with the first quartile NLR, the second, third and fourth quartiles NLR were independent risk predictors for ischemic stroke (P for trend < 0.001); the third and fourth quartiles were independent predictors for ICAS (P for trend < 0.001). The mediation analysis showed that ICAS partially mediated the association between NLR and ischemic stroke, accounting for 14.4% of the total effect (P < 0.001). CONCLUSIONS: NLR was significantly associated with ICAS and ischemic stroke. Besides, ICAS partially mediated the association between NLR and ischemic stroke.

miR32-5p promoted vascular smooth muscle cell calcification by upregulating TNFα in the microenvironment.

BACKGROUND: Vascular calcification is often associated with chronic inflammation and is a risk factor for brain arterial stiffness. Our previous results showed that miR32-5p was positively correlated with vascular smooth muscle cells (VSMC) calcification, but it is unclear whether miR32-5p promoted VSMC calcification by regulating inflammatory factor production. RESULTS: In this study, bioinformatics analysis was used to select tumour necrosis factor α (TNFα) as a candidate inflammatory factor associated with calcification. Moreover, alizarin red staining and qRT-PCR analysis revealed that TNFα produced by BV2 cells was the key promoting factor of VSMC calcification. Interestingly, the expression of TNFα was significantly increased at the mRNA and protein levels after miR32-5p mimic treatment but significantly decreased after miR32-5p antagomir treatment. To explore the mechanism of the regulation of TNFα expression by miR32-5p, bioinformatics analysis indicated that PIKfyve was a candidate target gene of miR32-5p, and luciferase assays verified that the expression of PIKfyve was significantly repressed by miR32-5p mimics. Importantly, rescue experiments showed that the expression of TNFα in BV2 cells treated with miR32-5p antagomir and the PIKfyve inhibitor YM201636 was significantly increased. CONCLUSIONS: The production of TNFα in microglia could be affected by miR32-5p targeting PIKfyve, and these results will be beneficial to reveal the mechanism of brain arterial calcification.

Global targetome analysis reveals critical role of miR-29a in pancreatic stellate cell mediated regulation of PDAC tumor microenvironment.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive forms of malignancies with a nearly equal incidence and mortality rates in patients. Pancreatic stellate cells (PSCs) are critical players in PDAC microenvironment to promote the aggressiveness and pathogenesis of the disease. Dysregulation of microRNAs (miRNAs) have been shown to play a significant role in progression of PDAC. Earlier, we observed a PSC-specific downregulation of miR-29a in PDAC pancreas, however, the mechanism of action of the molecule in PSCs is still to be elucidated. The current study aims to clarify the regulation of miR-29a in PSCs and identifies functionally important downstream targets that contribute to tumorigenic activities during PDAC progression. METHODS: In this study, using RNAseq approach, we performed transcriptome analysis of paired miR-29a overexpressing and control human PSCs (hPSCs). Enrichment analysis was performed with the identified differentially expressed genes (DEGs). miR-29a targets in the dataset were identified, which were utilized to create network interactions. Western blots were performed with the top miR-29a candidate targets in hPSCs transfected with miR-29a mimic or scramble control. RESULTS: RNAseq analysis identified 202 differentially expressed genes, which included 19 downregulated direct miR-29a targets. Translational repression of eight key pro-tumorigenic and -fibrotic targets namely IGF-1, COL5A3, CLDN1, E2F7, MYBL2, ITGA6 and ADAMTS2 by miR-29a was observed in PSCs. Using pathway analysis, we find that miR-29a modulates effectors of IGF-1-p53 signaling in PSCs that may hinder carcinogenesis. We further observe a regulatory role of the molecule in pathways associated with PDAC ECM remodeling and tumor-stromal crosstalk, such as INS/IGF-1, RAS/MAPK, laminin interactions and collagen biosynthesis. CONCLUSIONS: Together, our study presents a comprehensive understanding of miR-29a regulation of PSCs, and identifies essential pathways associated with PSC-mediated PDAC pathogenesis. The findings suggest an anti-tumorigenic role of miR-29a in the context of PSC-cancer cell crosstalk and advocates for the potential of the molecule in PDAC targeted therapies.

Astrocyte-Specific Deletion of Sox2 Promotes Functional Recovery After Traumatic Brain Injury.

Injury to the adult brain induces activation of local astrocytes, which serves as a compensatory response that modulates tissue damage and recovery. However, the mechanism governing astrocyte activation during brain injury remains largely unknown. Here we provide in vivo evidence that SOX2, a transcription factor critical for stem cells and brain development, is also required for injury-induced activation of adult cortical astrocytes. Genome-wide chromatin immunoprecipitation-seq analysis of mouse cortical tissues reveals that SOX2 binds to regulatory regions of genes associated with signaling pathways that control glial cell activation, such as Nr2e1, Mmd2, Wnt7a, and Akt2. Astrocyte-specific deletion of Sox2 in adult mice greatly diminishes glial response to controlled cortical impact injury and, most unexpectedly, dampens injury-induced cortical loss and benefits behavioral recovery of mice after injury. Together, these results uncover an essential role of SOX2 in somatic cells under pathological conditions and indicate that SOX2-dependent astrocyte activation could be targeted for functional recovery after traumatic brain injury.

Sex Differences in Cancer Cachexia.

PURPOSE OF REVIEW: Cachexia, a feature of cancer and other chronic diseases, is marked by progressive weight loss and skeletal muscle wasting. This review aims to highlight the sex differences in manifestations of cancer cachexia in patients, rodent models, and our current understanding of the potential mechanisms accounting for these differences. RECENT FINDINGS: Male cancer patients generally have higher prevalence of cachexia, greater weight loss or muscle wasting, and worse outcomes compared with female cancer patients. Knowledge is increasing about sex differences in muscle fiber type and function, mitochondrial metabolism, global gene expression and signaling pathways, and regulatory mechanisms at the levels of sex chromosomes vs. sex hormones; however, it is largely undetermined how such sex differences directly affect the susceptibility to stressors leading to muscle wasting in cancer cachexia. Few studies have investigated basic mechanisms underlying sex differences in cancer cachexia. A better understanding of sex differences would improve cachexia treatment in both sexes.

IL-6 and PD-L1 antibody blockade combination therapy reduces tumour progression in murine models of pancreatic cancer.

OBJECTIVE: Limited efficacy of immune checkpoint inhibitors in pancreatic ductal adenocarcinoma (PDAC) has prompted investigation into combination therapy. We hypothesised that interleukin 6 (IL-6) blockade would modulate immunological features of PDAC and enhance the efficacy of anti-programmed death-1-ligand 1 (PD-L1) checkpoint inhibitor therapy. DESIGN: Transcription profiles and IL-6 secretion from primary patient-derived pancreatic stellate cells (PSCs) were analyzed via Nanostring and immunohistochemistry, respectively. In vivo efficacy and mechanistic studies were conducted with antibodies (Abs) targeting IL-6, PD-L1, CD4 or CD8 in subcutaneous or orthotopic models using Panc02, MT5 or KPC-luc cell lines; and the aggressive, genetically engineered PDAC model (KrasLSL-G12D, Trp53LSL-R270H, Pdx1-cre, Brca2F/F (KPC-Brca2 mice)). Systemic and local changes in immunophenotype were measured by flow cytometry or immunohistochemical analysis. RESULTS: PSCs (n=12) demonstrated prominent IL-6 expression, which was localised to stroma of tumours. Combined IL-6 and PD-L1 blockade elicited efficacy in mice bearing subcutaneous MT5 (p<0.02) and Panc02 tumours (p=0.046), which was accompanied by increased intratumoural effector T lymphocytes (CD62L-CD44-). CD8-depleting but not CD4-depleting Abs abrogated the efficacy of combined IL-6 and PD-L1 blockade in mice bearing Panc02 tumours (p=0.0016). This treatment combination also elicited significant antitumour activity in mice bearing orthotopic KPC-luc tumours and limited tumour progression in KPC-Brca2 mice (p<0.001). Histological analysis revealed increased T-cell infiltration and reduced α-smooth muscle actin cells in tumours from multiple models. Finally, IL-6 and PD-L1 blockade increased overall survival in KPC-Brca2 mice compared with isotype controls (p=0.0012). CONCLUSIONS: These preclinical results indicate that targeted inhibition of IL-6 may enhance the efficacy of anti-PD-L1 in PDAC.

Asymmetric synthesis of CF3-containing tetrahydroquinoline via a thiourea-catalyzed cascade reaction.

An organocatalytic asymmetric method for the synthesis of 2-CF3 tetrahydroquinoline has been achieved. The cascade reaction of 2-aminochalcones with ß-CF3 nitroalkenes afforded the products bearing three contiguous stereogenic centers in good yields with excellent diastereoselectivities and enantioselectivities.

Combination of the clustered regularly interspaced short palindromic repeats (CRISPR)-associated 9 technique with the piggybac transposon system for mouse in utero electroporation to study cortical development.

In utero electroporation (IUE) is commonly used to study cortical development of cerebrum by downregulating or overexpressing genes of interest in neural progenitor cells (NPCs) of small mammals. However, exogenous plasmids are lost or diluted over time. Furthermore, gene knockdown based on short-hairpin RNAs may exert nonspecific effects that lead to aberrant neuronal migration. Genomic engineering by the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system has great research and therapeutic potentials. Here we integrate the CRISPR/Cas9 components into the piggyBac (PB) transposon system (the CRISPR/Cas9-PB toolkit) for cortical IUEs. The mouse Sry-related HMG box-2 (Sox2) gene was selected as the target for its application. Most transduced cortical NPCs were depleted of SOX2 protein as early as 3 days post-IUE, whereas expressions of SOX1 and PAX6 remained intact. Furthermore, both the WT Cas9 and the D10A nickase mutant Cas9n showed comparable knockout efficiency. Transduced cortical cells were purified with fluorescence-activated cell sorting, and effective gene editing at the Sox2 loci was confirmed. Thus, application of the CRISPR/Cas9-PB toolkit in IUE is a promising strategy to study gene functions in cortical NPCs and their progeny. © 2016 Wiley Periodicals, Inc.

Single-Side Two-Location Spotlight Imaging for Building Based on MIMO Through-Wall-Radar.

Through-wall-radar imaging is of interest for mapping the wall layout of buildings and for the detection of stationary targets within buildings. In this paper, we present an easy single-side two-location spotlight imaging method for both wall layout mapping and stationary target detection by utilizing multiple-input multiple-output (MIMO) through-wall-radar. Rather than imaging for building walls directly, the images of all building corners are generated to speculate wall layout indirectly by successively deploying the MIMO through-wall-radar at two appropriate locations on only one side of the building and then carrying out spotlight imaging with two different squint-views. In addition to the ease of implementation, the single-side two-location squint-view detection also has two other advantages for stationary target imaging. The first one is the fewer multi-path ghosts, and the second one is the smaller region of side-lobe interferences from the corner images in comparison to the wall images. Based on Computer Simulation Technology (CST) electromagnetic simulation software, we provide multiple sets of validation results where multiple binary panorama images with clear images of all corners and stationary targets are obtained by combining two single-location images with the use of incoherent additive fusion and two-dimensional cell-averaging constant-false-alarm-rate (2D CA-CFAR) detection.

MiR-138 inhibits cell proliferation and reverses epithelial-mesenchymal transition in non-small cell lung cancer cells by targeting GIT1 and SEMA4C.

Non-small-cell lung cancer (NSCLC) is one of the most common and lethal malignant tumours worldwide with a poor 5-year survival rate. Recent studies indicated that miRNAs have been involved in the tumorigenic driver pathways in NSCLC, but the relevant molecular mechanisms are not well-understood. In this study, we investigated the biological functions and molecular mechanisms of miR-138 in human NSCLC. The effects of miR-138 on the NSCLC cell growth and epithelial-mesenchymal transition (EMT) were first examined. Then the targeting connections of miR-138 with G-protein-coupled receptor kinase-interacting protein 1 (GIT1) and semaphorin 4C (SEMA4C) were confirmed by dual luciferase reporter assays. Finally, the effects of GIT1 and SEMA4C on the NSCLC cell growth and EMT were investigated respectively. We found that the ectopic expression of miR-138 resulted in a significant inhibition of NSCLC growth and reversion of EMT. GIT1 and SEMA4C were identified as two novel targets of miR-138. Furthermore, GIT1 and SEMA4C knockdown inhibited the cell growth and reversed EMT, just like the effects of miR-138 overexpression on NSCLC cells, whereas ectopic expression of GIT1 and SEMA4C partly rescued the suppressive effects of miR-138 in NSCLC cells. These data represent a crucial step towards the understanding of the novel roles and molecular mechanism of miR-138, GIT1 and SEMA4C in NSCLC progression, which may provide some new targets or prognostic biomarkers for NSCLC treatment, thus having implications in translational oncology.

Delayed leukoencephalopathy of non-small cell lung cancer patients with brain metastases underwent whole brain radiation therapy.

To explore the incidence, MR imaging findings, dynamic developing process of delayed leukoencephalopathy (DLE) in non-small cell lung cancer (NSCLC) patients with brain metastases patients who undergone whole brain radiation (WBRT) therapy, we retrospectively reviewed 48 NSCLC patients who underwent WBRT for brain metastases from January 2010 through June 2015 and had evaluable magnetic resonance imaging after treatment. The DLE were graded using a scale to evaluate T2-FLAIR (fluid attenuated image recovery) images: grade 1 = little or no white matter hyperintensity, grade 2 = limited periventricular hyperintensity and grade 3 = diffuse white matter hyperintensity. 48 NSCLC patients with brain metastases were enrolled. The median age of these patients was 55.7 years (range 33-75 years). The median follow-up was 12 months. The characteristic MR imaging of DLE in those patients was bilaterally diffuse white matter T2 hyperintensity around the periventricular areas without enhancement, sparing from U-fiber, callosum and gray matter structure. The incidence of DLE developed 6.25% (3/48), 30.00% (12/40), 48.39% (15/31), 61.90% (13/21), 85.71% (6/7), 100% (3/3) in those patients who were followed up for 3, 6, 9, 12, 24, 36 months, respectively. Through increased understanding of it, it may be possible to help clinicians develop further therapeutic strategies to maximize benefit while limiting potential long term toxicities. These data supplement existing reports regarding the late effects of WBRT in NSCLC patients with brain metastasis.