Clinical features and treatment options for pediatric adrenal incidentalomas: a retrospective single center study.

BACKGROUND: The aim of this study was to investigate the clinical features and treatment options for pediatric adrenal incidentalomas(AIs) to guide the diagnosis and treatment of these tumors. METHODS: The clinical data of AI patients admitted to our hospital between December 2016 and December 2022 were collected and retrospectively analyzed. All patients were divided into neonatal and nonneonatal groups according to their age at the time of the initial consultation. RESULTS: In the neonatal group, 13 patients were observed and followed up, and the masses completely disappeared in 8 patients and were significantly reduced in size in 5 patients compared with the previous findings. Four patients ultimately underwent surgery, and the postoperative pathological diagnosis was neuroblastoma in three patients and teratoma in one patient. In the nonneonatal group, there were 18 cases of benign tumors, including 9 cases of ganglioneuroma, 2 cases of adrenocortical adenoma, 2 cases of adrenal cyst, 2 cases of teratoma, 1 case of pheochromocytoma, 1 case of nerve sheath tumor, and 1 case of adrenal hemorrhage; and 20 cases of malignant tumors, including 10 cases of neuroblastoma, 9 cases of ganglioneuroblastoma, and 1 case of adrenocortical carcinoma. CONCLUSIONS: Neuroblastoma is the most common type of nonneonatal AI, and detailed laboratory investigations and imaging studies are recommended for aggressive evaluation and treatment in this population. The rate of spontaneous regression of AI is high in neonates, and close observation is feasible if the tumor is small, confined to the adrenal gland and has no distant metastasis.

Eye growth pattern of myopic children wearing spectacle lenses with aspherical lenslets compared with non-myopic children.

INTRODUCTION: To evaluate eye growth of children wearing spectacle lenses with highly aspherical lenslets (HAL), slightly aspherical lenslets (SAL) and single-vision lenses (SVL) compared to eye growth patterns in non-myopes in Wenzhou, China. METHODS: The randomised trial had 170 myopic children (aged 8-13 years) randomly assigned to the HAL, SAL or SVL group. Normal eye growth was examined using 700 non-myopic schoolchildren (aged 7-9 years) in the Wenzhou Medical University-Essilor Progression and Onset of Myopia (WEPrOM) cohort study using logistic function models. Slow, normal and fast eye growth was defined as range of values <25th, 25th-75th and >75th percentiles, respectively. RESULTS: The predicted upper limits of slow eye growth (25th percentile) among non-myopes aged 7-10 years and 11-13 years were 0.20-0.13 and 0.08-0.01 mm (after 2-year period; 0.37-0.33 and 0.29-0.14 mm), respectively, while the upper limits of normal eye growth (75th percentile) were 0.32-0.31 and 0.28-0.10 mm (after 2-year period; 0.58-0.55 and 0.50-0.24 mm), respectively. The 2-year trial had 157 children, 96 of whom wore their lenses full time (everyday ≥12 h/day). The mean 2-year axial length change for HAL, SAL and SVL was 0.34, 0.51 and 0.69 mm (0.28, 0.46 and 0.69 mm in full-time wear), respectively. Slow eye growth was found in 35%, 17% and 2% (44%, 29% and 3% in full-time wear); normal eye growth in 35%, 26% and 12% (44%, 32% and 9% in full-time wear) and fast eye growth in 30%, 57% and 86% (12%, 39% and 88% in full-time wear), respectively (p < 0.001). CONCLUSIONS: The eye growth pattern in approximately 90% wearing HAL full time (compared with about 10% wearing SVL full time) was similar or slower than that of non-myopic children both after 1- and 2-year periods.

Small molecules reprogram reactive astrocytes into neuronal cells in the injured adult spinal cord.

INTRODUCTION: Ectopic expression of transcription factor-mediated in vivo neuronal reprogramming provides promising strategy to compensate for neuronal loss, while its further clinical application may be hindered by delivery and safety concerns. As a novel and attractive alternative, small molecules may offer a non-viral and non-integrative chemical approach for reprogramming cell fates. Recent definitive evidences have shown that small molecules can convert non-neuronal cells into neurons in vitro. However, whether small molecules alone can induce neuronal reprogramming in vivo remains largely unknown. OBJECTIVES: To identify chemical compounds that can induce in vivo neuronal reprogramming in the adult spinal cord. METHODS: Immunocytochemistry, immunohistochemistry, qRT-PCR and fate-mapping are performed to analyze the role of small molecules in reprogramming astrocytes into neuronal cells in vitro and in vivo. RESULTS: By screening, we identify a chemical cocktail with only two chemical compounds that can directly and rapidly reprogram cultured astrocytes into neuronal cells. Importantly, this chemical cocktail can also successfully trigger neuronal reprogramming in the injured adult spinal cord without introducing exogenous genetic factors. These chemically induced cells showed typical neuronal morphologies and neuron-specific marker expression and could become mature and survive for more than 12 months. Lineage tracing indicated that the chemical compound-converted neuronal cells mainly originated from post-injury spinal reactive astrocytes. CONCLUSION: Our proof-of-principle study demonstrates that in vivo glia-to-neuron conversion can be manipulated in a chemical compound-based manner. Albeit our current chemical cocktail has a lowreprogramming efficiency, it will bring in vivo cell fate reprogramming closer to clinical application in brain and spinal cord repair. Future studies should focus on further refining our chemical cocktail and reprogramming approach to boost the reprogramming efficiency.

Bioinformatics identification of prognostic genes and potential interaction analysis in renal cell carcinoma.

Background: Renal cell carcinoma (RCC) is one of the ten most prevalent cancers in the world and its incidence has been rising over the past decade. However, effective biomarkers to predict the prognosis of patients remains absent, and the exact molecular mechanism of the disease remains unclear. Therefore, the identification of key genes and their biological pathways are of great significance to identify the differential expressed genes associated with the prognosis for patients with RCC, and to further explore their potential protein-protein interactions (PPIs) in tumorigenesis. Methods: The gene expression microarray data for GSE15641 and GSE40435 were extracted from the Gene Expression Omnibus (GEO) database, including 150 primary tumors and their matched adjacent non-tumor tissues. Afterwards, gene expression for fold changes (FCs) and P value for tumor and non-tumor tissues were analyzed using online tool GEO2R. Gene expression with logFCs of greater than two combined with P value of lower than 0.01 were considered as candidate targets for treatment of RCC. The survival analysis of candidate genes was performed by online software OncoLnc. The PPI network was implemented with Search Tool for the Retrieval of Interacting Genes (STRING). Results: In total, there were 625 differentially expressed genes (DEGs) in GSE15641, including 415 increased and 210 decreased genes. A total of 343 DEGs were identified in the GSE40435 with 101 upregulated and 242 downregulated genes, the 20 genes with highest FC in high or low expression in each database were summarized. Five candidate genes were overlapped genes in the two GEO datasets. However, aldolase, fructose-bisphosphate B (ALDOB) was found to be the only gene affecting the prognosis. A number of critical genes were identified behind the mechanism, of which they interacted with ALDOB. Among them, phosphofructokinase, platelet (PFKP), phosphofructokinase, muscle (PFKM), pyruvate kinase L/R (PKLR), and fructose-bisphosphatase 1 (FBP1) showed a better prognosis, whereas only glyceraldehyde-3-phosphate dehydrogenase (GAPDH) rendered a bleak outcome. Conclusions: Five genes were found to be overlappingly expressed in the top 20 greatest FC in two human GEO datasets. This is of great value in the treatment and prognosis of RCC.

Identification and characterization of sex-dependent gene expression profile in glioblastoma.

Glioblastoma (GBM) is the most lethal primary tumor in the human brain and lacks favorable treatment options. Sex differences in the outcome of GBM are broadly acknowledged, but the underlying molecular mechanisms remain largely unknown. To identify the sex-dependent critical genes in the progression of GBM, raw data from several microarray datasets with the same array platform were downloaded from the Gene Expression Omnibus (GEO) database. These datasets included tumorous and normal tissue from patients with GBM and crucial sex features. Then, the differentially expressed genes (DEGs) in female and male tumors were identified via bioinformatics analysis, respectively. Functional signatures of the identified DEGs were further annotated by Gene Ontology (GO) and pathway enrichment analyses. Venn diagram and functional protein-protein interaction (PPI) network analyses were performed to screen out the sex-specific DEGs. Survival analysis of patients with differences in the expression level of selected genes was then carried out using the data from The Cancer Genome Atlas (TCGA). Here, we showed that ECT2, AURKA, TYMS, CDK1, NCAPH, CENPU, OIP5, KIF14, ASPM, FBXO5, SGOL2, CASC5, SHCBP1, FN1, LOX, IGFBP3, CSPG4, and CD44 were enriched in female tumor samples, whereas TNFSF13B, CXCL10, CXCL8, CXCR4, TLR2, CCL2, and FCGR2A were enriched in male tumor samples. Among these key genes, interestingly, ECT2 was associated with increased an survival rate for female patients, whileTNFSF13B could be regarded as a potential marker of poor prognosis in male patients. These results suggested that sex differences in patients may be attributed to the heterogeneous gene activity, which might influence the oncogenesis and the outcomes of GBM.

Topoisomerase IIA in adult NSCs regulates SVZ neurogenesis by transcriptional activation of Usp37.

Topoisomerase IIA (TOP2a) has traditionally been known as an important nuclear enzyme that resolves entanglements and relieves torsional stress of DNA double strands. However, its function in genomic transcriptional regulation remains largely unknown, especially during adult neurogenesis. Here, we show that TOP2a is preferentially expressed in neurogenic niches in the brain of adult mice, such as the subventricular zone (SVZ). Conditional knockout of Top2a in adult neural stem cells (NSCs) of the SVZ significantly inhibits their self-renewal and proliferation, and ultimately reduces neurogenesis. To gain insight into the molecular mechanisms by which TOP2a regulates adult NSCs, we perform RNA-sequencing (RNA-Seq) plus chromatin immunoprecipitation sequencing (ChIP-Seq) and identify ubiquitin-specific protease 37 (Usp37) as a direct TOP2a target gene. Importantly, overexpression of Usp37 is sufficient to rescue the impaired self-renewal ability of adult NSCs caused by Top2a knockdown. Taken together, this proof-of-principle study illustrates a TOP2a/Usp37-mediated novel molecular mechanism in adult neurogenesis, which will significantly expand our understanding of the function of topoisomerase in the adult brain.

NOTCH1 signaling regulates the latent neurogenic program in adult reactive astrocytes after spinal cord injury.

Background: Direct reprogramming of astrocytes into neurons opens up a new avenue for neuroregenerative medicine. However, the poor understanding of the molecular mechanisms underpinning the latent neurogenic program in astrocytes has largely restricted this strategy towards safe and effective clinical therapies. Methods: Immunocytochemistry, immunohistochemistry, western blotting, qRT-PCR, gene knockdown and fate-mapping are performed to analyze the role of NOTCH1 signaling in regulation of the latent neurogenic program in reactive astrocytes after spinal cord injury. Results: Western blotting analysis highlights that NOTCH1 is a key signaling mediating Ascl1- and Neurog2-driven astrocyte-to-neuron conversion. Inhibition of NOTCH1 signaling in cultured astrocytes by shRNA or DAPT (a NOTCH1 inhibitor) is sufficient to reprogram them into neurons by upregulating the expression of pro-neural transcription factors, including NeuroD1, NeuroD2, Pax6, Lmx1a and Lhx6. In the spinal cord of adult mouse, the expression of Notch1 is detected in resident astrocytes, which was significantly increased after spinal cord injury (SCI). Genetical knockdown of NOTCH1 signaling alone successfully triggers endogenous reactive astrocytes reprogramming into neurons in the injured adult spinal cord. Importantly, pharmacologically blocking NOTCH1 signaling with small molecule DAPT alone can also induce in situ astrocyte-to-neuron conversion after SCI. Conclusions: We identify NOTCH1 as a key common signaling pathway in reactive astrocyte that provides a barrier for cell fate conversion. This proof-of-principle study will significantly expand our molecular understanding of astroglial-lineage reprogramming and overcoming the NOTCH1 gatekeeper with small molecules may provide a transgene-free approach for in vivo chemical neuronal reprogramming with potential clinical application in neuroregeneration.

Development and validation of a novel nomogram for predicting the occurrence of myopia in schoolchildren: A prospective cohort study.

PURPOSE: Myopia is a major public health issue and occurs at young ages. Apart from its high prevalence, myopia results in high costs and irreversible blinding diseases. Accurate prediction of the risk of myopia onset is crucial for its precise prevention. We aimed to develop and validate an effective nomogram for predicting myopia onset in schoolchildren. DESIGN: School-based prospective cohort study. METHODS: A total of 1073 schoolchildren were enrolled from November 2014 to May 2019 in China, and were divided into the training and validation cohorts. Myopia was defined as a spherical equivalent refraction (SER) ≤-0.5 diopters. Predictors of myopia were determined through the least absolute shrinkage and selection operator regression and multivariable Cox proportional hazard model based on the training cohort. The predictive performance of the nomogram was validated internally through time-dependent receiver operating characteristic (ROC) curves, calibration plot, decision curve analysis, and Kaplan-Meier curves. RESULTS: Independent predictors at baseline including gender, SER, axial length, corneal refractive power, and positive relative accommodation were included in the nomogram prediction model. This nomogram demonstrated excellent calibration, clinical net benefit, and discrimination, with all the area under the ROC curves (AUCs) between 0.74 and 0.86 in the training and validation cohorts. The Kaplan-Meier curves showed that 3 distinct risk groups stratified through X-tile analysis were well discriminated and robust among subgroups. The Harrell's C-index and net reclassification improvement demonstrated that the nomogram substantially improved compared with previous models. An online myopia risk calculator was generated for better individual prediction. CONCLUTIONS: The nomogram provides accurate and individual prediction of myopia onset in schoolchildren. External validation is needed to verify the generalizability of this nomogram.

Early embryonic transcriptomes of Zeugodacus tau provide insight into sex determination and differentiation genes.

Zeugodacus tau (Walker) is an invasive pest. The sterile insect technique is an environment-friendly method for pest control. Understanding the mechanism of sex determination will contribute to improving efficiency of this technique. In this study, we identified the transformer (tra) gene in Z. tau. One female-specific and two male-specific isoforms of tra were found in Z. tau, and the male-specific splicing pattern of tra was found to occur 5 h after egg laying. We performed transcriptome sequencing at 1 h (E1), 5 h (E5), and 9 h (E9) after egg laying and obtained high-quality transcriptome libraries of early embryo development. We identified 13 297 and 11 713 differentially expressed genes (DEGs) from E5 versus E1 and E9 versus E1 comparisons, respectively. To explore the potential functions of the DEGs during embryonic development, Gene Ontology, Clusters of Orthologous Groups of proteins, and Kyoto Encyclopedia of Genes and Genomes analyses were performed. Twenty-six genes potentially involved in sex determination or differentiation, including Maleness-on-the-Y (MoY), were identified in Z. tau. To verify the transcriptome results, 15 genes were selected for quantitative real-time PCR validation. The results were consistent with the transcriptome sequencing results. Moreover, U2 small nuclear riboprotein auxiliary factor (U2AF-50), female lethal d (fl(2)d), and virilizer (vir) were highly expressed at E5, indicating that they may be related to the sex-specific splicing of tra. Further functional analysis is needed to confirm this speculation. Our data provide an insight into the mechanism underlying sex determination and differentiation in tephritid species.

[Biological characteristics and functions of NG2-glia].

NG2-glia are a major type of glial cells that are widely distributed in the central nervous system (CNS). Under physiological conditions, they mainly differentiate into oligodendrocytes and contribute to the myelination of axons, so they are generally called oligodendrocyte progenitor cells. Emerging evidence suggests that NG2-glia not only act as the precursors of oligodendrocytes but also possess many other biological properties and functions. For example, NG2-glia can form synapse with neurons and participate in energy metabolism and immune regulation. Under pathological conditions, NG2-glia can also differentiate into astrocytes, Schwann cells and even neurons, which are involved in CNS injury and repair. Therefore, a deeper understanding of the biological characteristics and functions of NG2-glia under physiological and pathological conditions will be helpful for the treatment of CNS injury and disease. This article reviews the recent advances in the biological characteristics and functions of NG2-glia.

Prediction of myopia onset with refractive error measured using non-cycloplegic subjective refraction: the WEPrOM Study.

BACKGROUND/AIMS: To evaluate the predictive performance of various predictors, including non-cycloplegic refractive error, for risk of myopia onset under pragmatic settings. METHODS: The Wenzhou Medical University Essilor Progression and Onset of Myopia Study is a prospective cohort study of schoolchildren aged 6-10 years from two elementary schools in Wenzhou, China. Non-cycloplegic refraction, ocular biometry and accommodation measurements were performed. Myopia was defined as spherical equivalent (SE) ≤-0.5 diopter (D). ORs using multivariable logistic regression were determined. Area under the curve (AUC) evaluation for predictors was performed. RESULTS: Schoolchildren who attended both baseline and 2-year follow-up were analysed (N=1022). Of 830 non-myopic children at baseline, the 2-year incidence of myopia was 27.6% (95% CI, 24.2% to 31.3%). Female gender (OR=2.2), more advanced study grades (OR=1.5), less hyperopic SE (OR=11.5 per D), longer axial length (AL; OR=2.3 per mm), worse presenting visual acuity (OR=2.3 per decimal), longer near work time (OR=1.1 per hour/day) and lower magnitude of positive relative accommodation (PRA; OR=1.4 per D) were associated with myopia onset. PRA (AUC=0.66), SE (AUC=0.64) and AL (AUC=0.62) had the highest AUC values. The combination of age, gender, parental myopia, SE, AL and PRA achieved an AUC of 0.74. CONCLUSION: Approximately one in four schoolchildren had myopia onset over a 2-year period. The predictors of myopia onset include lower magnitude of PRA, less hyperopic SE, longer AL and female gender. Of these, non-cycloplegic SE and PRA were the top single predictors, which can facilitate risk profiling for myopia onset.

Association of Myopia and Genetic Variants of TGFB2-AS1 and TGFBR1 in the TGF-ß Signaling Pathway: A Longitudinal Study in Chinese School-Aged Children.

BACKGROUND: Myopia is a complex multifactorial condition which involves several overlapping signaling pathways mediated by distinct genes. This prospective cohort study evaluated the associations of two genetic variants in the TGF-ß signaling pathway with the onset and progression of myopia and ocular biometric parameters in Chinese school-aged children. METHODS: A total of 556 second grade children were examined and followed up for 3.5 years. Non-cycloplegic refraction and ocular biometric parameters were measured annually. Multivariate regression analysis was used to assess the effect of the TGFBR1 rs10760673 and TGFB2-AS1 rs7550232 variants on the occurrence and progression of myopia. A 10,000 permutations test was used to correct for multiple testing. Functional annotation of single nucleotide polymorphisms (SNPs) was performed using RegulomeDB, HaploReg, and rVarBase. RESULTS: A total of 448 children were included in the analysis. After adjustments for gender, age, near work time and outdoor time with 10,000 permutations, the results indicated that the C allele and the AC or CC genotypes of rs7550232 adjacent to TGFB2-AS1 were associated with a significantly increased risk of the onset of myopia in two genetic models (additive: P' = 0.022; dominant: P' = 0.025). Additionally, the A allele and the AA or AG genotypes of rs10760673 of TGFBR1 were associated with a significant myopic shift (additive: P' = 0.008; dominant: P' = 0.028; recessive: P' = 0.027). Furthermore, rs10760673 was associated with an increase in axial length (AL) (P' = 0.013, ß = 0.03) and a change in the ratio of AL to the corneal radius of curvature (AL/CRC) (P' = 0.031, ß = 0.003). Analysis using RegulomeDB, HaploReg, and rVarBase indicated that rs7550232 is likely to affect transcription factor binding, any motif, DNase footprint, and DNase peak. CONCLUSION: The present study indicated that rs10760673 and rs7550232 may represent susceptibility loci for the progression and onset of myopia, respectively, in school-aged children. Associations of the variants of the TGFBR1 and TGFB2-AS1 genes with myopia may be mediated by the TGF-ß signaling pathway; this hypothesis requires validation in functional studies. This trial was registered as ChiCTR1900020584 at www.Chictr.org.cn.

Patient transfer influences the prognosis of pediatric patients operated for testicular torsion: a single-center experience.

BACKGROUND: Testicular torsion (TT) remains an emerging issue for pediatric patients. This study's objective was to determine risk factors of TT outcomes in the Chinese pediatric cohort from a single center. METHODS: We performed a retrospective cohort study of patients who met the inclusion criteria in our center from 2013 to 2018. Clinical demographics, and TT-related data, including laterality, torsion degree, torsion direction, position to the cavity of tunica vaginalis, enorchia, and outcomes, were reviewed and extracted from medical charts and databases. Statistical analysis was conducted to compare and figure out the risk factors of TT outcomes. RESULTS: A total of 84 pediatric patients were enrolled in this study. Among these variables, age, duration of symptoms, and the patient transfer were significantly associated with the outcomes of TT (P<0.005). Patients transferred from other medical facilities underwent more orchiectomy than those without transfer (univariate analysis, P<0.0001; multivariate analysis, P=0.001). No difference was found in other variables between patients with or without transfer (P>0.05). Moreover, transferred patients tended to show worse testicular function. CONCLUSIONS: We have reported that age, duration of symptoms, and patient transfer were three significant risk factors in this cohort. Patients with transfer tended to suffer from more orchiectomy and worse prognosis of TT.

Foveal pit morphological changes in asymptomatic carriers of the G11778A mutation with Leber's hereditary optic neuropathy.

AIM: To investigate the foveal pit morphology changes in unaffected carriers and affected Leber's hereditary optic neuropathy (LHON) patients with the G11778A mutation from one family. METHODS: This study was a prospective cross-sectional study. Both eyes from 16 family members (age from 9 to 47y) with the G11778A mutation were analyzed and compared with 1 eye from 20 normal control subjects. Eleven family members with the G11778A mutation but without optic neuropathy were classified as unaffected carriers (n=22 eyes). Five family members (n=10 eyes) expressed the LHON phenotype and were classified as affected patients. Retinal images of all the subjects were taken by optical coherence tomography (OCT), and an automatic algorithm was used to segment the retina to eight layers. Horizontal and vertical OCT images centered on the fovea were used to measure intra-retinal layer thicknesses and foveal morphometry. RESULTS: Thicker foveal thickness, thinner foveal pit depth, and flatter foveal slopes were observed in unaffected carriers and affected LHON patients (all P<0.001). Further, the slopes of all four sectors in the LHON were flatter than those in the unaffected carriers (all P<0.001). Compared with the control group, affected LHON patients had a thinner retinal nerve fiber layer (RNFL), ganglion cell layer and inner plexiform layer (GCL+IPL), and total retina (all P<0.01). The retinal nerve fiber layer (RNFL) of affected patients was 38.0% thinner than that of controls while the GCL+IPL was 40.1% thinner. CONCLUSION: The foveal pit morphology shows changes in both unaffected carriers and affects patients. RNFL and GCL+IPL are thinner in affected LHON patients but not in unaffected carriers.

Expanding the Phenotypic and Genotypic Landscape of Nonsyndromic High Myopia: A Cross-Sectional Study in 731 Chinese Patients.

Purpose: High myopia (HM) is defined as a refractive error worse than -6.00 diopter (D). This study aims to update the phenotypic and genotypic landscape of nonsyndromic HM and to establish a biological link between the phenotypic traits and genetic deficiencies. Methods: A cross-sectional study involving 731 participants varying in refractive error, axial length (AL), age, myopic retinopathy, and visual impairment. The phenotypic traits were analyzed by four ophthalmologists while mutational screening was performed in eight autosomal causative genes. Finally, we assessed the clinical relevance of identified mutations under the guidance of the American College of Medical Genetics and Genomics. Results: The relationship between refractive error and AL varied in four different age groups ranging from 3- to 85-years old. In adult groups older than 21 years, 1-mm increase in AL conferred 10.84% higher risk of pathologic retinopathy (Category ≥2) as well as 7.35% higher risk of low vision (best-corrected visual acuities <0.3) with P values < 0.001. The prevalence rates of pathologic retinopathy and low vision both showed a nonlinear positive correlation with age. Forty-five patients were confirmed to harbor pathogenic mutations, including 20 novel mutations. These mutations enriched the mutational pool of nonsyndromic HM to 1.5 times its previous size and enabled a statistically significant analysis of the genotype-phenotype correlation. Finally, SLC39A5, CCDC111, BSG, and P4HA2 were more relevant to eye elongation, while ZNF644, SCO2, and LEPREL1 appeared more relevant to refracting media. Conclusions: Our findings shed light on how multiple HM-related phenotypes are associated with each other and their link with gene variants.

Direct neuronal reprogramming of olfactory ensheathing cells for CNS repair.

Direct conversion of readily available non-neural cells from patients into induced neurons holds great promise for neurological disease modeling and cell-based therapy. Olfactory ensheathing cells (OECs) is a unique population of glia in olfactory nervous system. Based on the regeneration-promoting properties and the relative clinical accessibility, OECs are attracting increasing attention from neuroscientists as potential therapeutic agents for use in neural repair. Here, we report that OECs can be directly, rapidly and efficiently reprogrammed into neuronal cells by the single transcription factor Neurogenin 2 (NGN2). These induced cells exhibit typical neuronal morphologies, express multiple neuron-specific markers, produce action potentials, and form functional synapses. Genome-wide RNA-sequencing analysis shows that the transcriptome profile of OECs is effectively reprogrammed towards that of neuronal lineage. Importantly, these OEC-derived induced neurons survive and mature after transplantation into adult mouse spinal cords. Taken together, our study provides a direct and efficient strategy to quickly obtain neuronal cells from adult OECs, suggestive of promising potential for personalized disease modeling and cell replacement-mediated therapeutic approaches to neurological disorders.

Inhibition of Glioma Development by ASCL1-Mediated Direct Neuronal Reprogramming.

Direct conversion of non-neural cells into induced neurons holds great promise for brain repair. As the most common malignant tumor in the central nervous system, glioma is currently incurable due to its exponential growth and invasive behavior. Given that neurons are irreversible postmitotic cells, reprogramming glioma cells into terminally differentiated neuron-like cells represents a potential approach to inhibit brain tumor development. We here show that human glioma cells can be directly, rapidly and efficiently reprogrammed into terminally differentiated neuron-like cells by the single transcription factor ASCL1 (Achaete-scute complex-like 1, also known as MASH1). These induced cells exhibit typical neuron-like morphology and express multiple neuron-specific markers. Importantly, ASCL1-mediated neuronal reprogramming drives human glioma cells to exit the cell cycle and results in dramatic inhibition of proliferation, both in vitro and in vivo. Taken together, this proof-of-principle study demonstrates a potential strategy for impeding brain tumor development by ASCL1-induced direct neuronal reprogramming.

Conditional ablation of reactive astrocytes to dissect their roles in spinal cord injury and repair.

Astrocytes become reactive in response to spinal cord injury (SCI) and ultimately form a histologically apparent glial scar at the lesion site. It is controversial whether astrocytic scar is detrimental or beneficial to the axonal regeneration and SCI repair. Therefore, much effort has focused on understanding the functions of reactive astrocytes. Here, we used a lentivirus-mediated herpes simplex thymidine kinase/ganciclovir (HSVtk/GCV) system to selectively kill scar-forming reactive proliferating astrocytes. The suicide gene expression was regulated by human glial fibrillary acidic protein (hGFAP) promoter, which is active primarily in astrocytes. Conditional ablation of reactive astrocytes in a mouse SCI model with crush injury impeded glial scar formation and resulted in widespread infiltration of inflammatory cells, increased neuronal loss, and severe tissue degeneration, which ultimately led to the failure of spontaneous functional recovery. These results suggest that reactive proliferating astrocytes play key roles in the healing process after SCI, shedding light on the potential benefit for the repair after central nervous system (CNS) injury.