不同直径混合肌腱重建前交叉韧带对膝关节运动学特征影响

目的评估不同直径混合肌腱(同种异体肌腱加强自体肌腱)重建前交叉韧带(ACL)对膝关节运动学特征影响。 方法回顾性分析2017年8月至2018年6月在南方医科大学第三附属医院使用混合肌腱行ACL重建术的57例患者资料。纳入标准：单侧膝ACL损伤并使用直径8 mm或9 mm混合肌腱重建ACL患者;年龄18至55岁并且有影像学证据显示骨骺闭合。排除标准：X片提示膝骨关节炎;术前膝关节活动受限;其他膝关节手术史;膝关节其他韧带损伤;需同时行半月板移植及软骨修复者。根据移植物直径大小不同分为：8 mm组(32例)、9 mm组(25例)。患者在术前、术后6个月、1年、2年完成随访,分析患侧膝关节6自由度的活动度及胫股运动学改变(以对侧膝关节为对照组)、移植物信号/噪声商(SNQ)值、Lysholm评分。各组术前及术后指标比较采用重复测量方差分析。 结果8 mm组(6.3%)、9 mm组(0%)的手术失败率差异无统计学意义(P＝0.499)。8 mm组在术后6个月的屈曲角度、术后1年的外旋角度比9 mm组高,差异具有统计学意义(F＝3.507,P＝0.034;F＝4.563,P＝0.013);8 mm组在术后6月的外侧位移、术后2年的外旋角度比对照组高,差异具有统计学意义(F＝3.596,P＝0.031;F＝9.997,P<0.001)。相较术后6个月、1年,两组在术后2年的移植物近端、中段、远端的SNQ值均呈下降趋势(F＝9.634、8.593、7.636,均为P<0.001)。9 mm组的Lysholm评分比8 mm组高,差异具有统计学意义(F＝6.116,P＝0.017)。 结论直径8 mm、9 mm的混合肌腱重建前交叉韧带有相似的手术失败率和移植物成熟度,但后者的膝关节运动学特征比前者更接近正常膝关节。     

High expression of miR-195 is related to favorable prognosis in cytogenetically normal acute myeloid leukemia

Background

Acute myeloid leukemia (AML) is a heterogeneous blood disease with poor treatment effect and high recurrence rate. With the deepening of non-coding RNA research, more and more miRNAs have been found to participate in various physiological processes of tumors. In this study, we tried to find the miRNA related to the prognosis of AML.

Methods

Collect gene expression data and clinical information of AML patients in the Cancer Genome Atlas database for statistical analysis. The expression level of miR-195 of each patient was standardized by logCPM and then produced as a box plot according to subtype classification. TargetScan was used to predict the target genes of miR-195, and these genes were subjected to GO pathway enrichment analysis by Metascape. Differential miRNAs were screened through the DESeq2 package in the R language. Survival rates were estimated using the Kaplan–Meier method and the log-rank test. The multivariate Cox proportional hazard models of EFS and OS were established.

Results

We found that the expression of miR-195 was the lowest in cytogenetically normal (CN-) AML, and high expression of miR-195 only promoted the prognosis of chemotherapy-only CN-AML patients (EFS: P?=?0.016; OS: P?=?0.035). Multivariate analysis showed that miR-195^high was a favorable and independent factor for CN-AML (both P?<?0.05). Further analysis showed that miR-195 may affect signal transduction through ANHAK2 in AML.

Conclusion

We found that high expression of miR-195 can increase prognosis time of chemotherapy-only CN-AML patients, providing a new possibility for treatment.

     

Rolling-translated EGFR variants sustain EGFR signaling and promote glioblastoma tumorigenicity

Background Aberrant epidermal growth factor receptor (EGFR) activation is observed in over 50% of cases of adult glioblastoma (GBM). Nevertheless, EGFR antibodies are ineffective in clinical GBM treatment, suggesting the existence of redundant EGFR activation mechanisms. Whether circular RNA (circRNA) encodes a protein involved in EGFR-driven GBM remains unclear. We reported an unexpected mechanism in which circular EGFR RNA (circ-EGFR) encodes a novel EGFR variant to sustained EGFR activation.Method We used RNA-seq, Northern blot, and Sanger sequencing to confirm the existence of circ-EGFR. Antibodies and a liquid chromatograph tandem mass spectrometer were used to identify circ-EGFR protein products. Lentivirus-transfected stable cell lines were used to assess the biological functions of the novel protein in vitro and in vivo. Clinical implications of circ-EGFR were assessed using 97 pathologically diagnosed GBM patient samples.Results The infinite open reading frame (iORF) in circ-EGFR translated repeating amino acid sequences via rolling translation and programmed −1 ribosomal frameshifting (-1PRF) induced out-of-frame stop codon (OSC), forming a polymetric novel protein-complex, which we termed rolling-translated EGFR (rtEGFR). rtEGFR directly interacted with EGFR, maintained EGFR membrane localization and attenuated EGFR endocytosis and degradation. Importantly, circ-EGFR levels correlated with the EGFR signature and predicted the poor prognosis of GBM patients. Deprivation of rtEGFR in brain tumor-initiating cells (BTICs) attenuated tumorigenicity and enhanced the anti-GBM effect.Conclusion Our findings identified the endogenous rolling-translated protein and provided strong clinical evidence that targeting rtEGFR could improve the efficiency of EGFR-targeting therapies in GBM.     

NEO100 enables brain delivery of blood‒brain barrier impermeable therapeutics

BackgroundIntracarotid injection of mannitol has been applied for decades to support brain entry of therapeutics that otherwise do not effectively cross the blood–brain barrier (BBB). However, the elaborate and high-risk nature of this procedure has kept its use restricted to well-equipped medical centers. We are developing a more straightforward approach to safely open the BBB, based on the intra-arterial (IA) injection of NEO100, a highly purified version of the natural monoterpene perillyl alcohol.MethodsIn vitro barrier permeability with NEO100 was evaluated by transepithelial/transendothelial electrical resistance and antibody diffusion assays. Its mechanism of action was studied by western blot, microarray analysis, and electron microscopy. In mouse models, we performed ultrasound-guided intracardiac administration of NEO100, followed by intravenous application of Evan’s blue, methotrexate, checkpoint-inhibitory antibodies, or chimeric antigen receptor (CAR) T cells.ResultsNEO100 opened the BBB in a reversible and nontoxic fashion in vitro and in vivo. It enabled greatly increased brain entry of all tested therapeutics and was well tolerated by animals. Mechanistic studies revealed effects of NEO100 on different BBB transport pathways, along with translocation of tight junction proteins from the membrane to the cytoplasm in brain endothelial cells.ConclusionWe envision that this procedure can be translated to patients in the form of transfemoral arterial catheterization and cannulation to the cerebral arteries, which represents a low-risk procedure commonly used in a variety of clinical settings. Combined with NEO100, it is expected to provide a safe, widely available approach to enhance brain entry of any therapeutic.     

IL-2基因转导小鼠肝癌细胞的实验研究

用重组人白细胞介素-2(IL-2)含信号肽cDNA的缺陷型逆转录病毒,将IL-2基因转导入小鼠H_(22)肝癌细胞株,经PCR和RT-PCR检测证实了转导后的细胞DNA内确有NeoR和IL-2基因的存在的表达。分别用光镜和电镜观察了经IL-2基因转录的H_(22)细胞体外形态,MTT法检测细胞体外增殖能力以及皮下接种H_(22)-IL-2细胞后观察肿瘤生长能力。结果表明经IL-2基因转导的鼠肝癌细胞体外增殖能力没有明显变化,但体内致瘤性却显著下降,丝裂霉素处理后作为瘤苗接种能抑制其后野生型H_(22)细胞的再次攻击。本研究为制备新型瘤苗打下了基础。     

Obesity-related glomerulopathy: insights from gene expression profiles of the glomeruli derived from renal biopsy samples

Obesity-related glomerulopathy (ORG) is an important complication of obesity. The pathophysiological mechanism of glomerular injury in ORG is incompletely understood. Gene expression profiles in the glomeruli obtained from renal biopsy samples of patients with ORG were investigated, using a microdissection technique combined with Affymetrix microarray analysis. Six patients presented with obesity, proteinuria, and biopsy-proven ORG were enrolled. Two sex- and age-matched donor kidneys were applied as the controls. Glomeruli were dissected out from renal biopsy samples under microscope, and total RNA was extracted using RNeasy Micro kit. After two rounds of T7 promoter-based RNA amplification, gene expression profiles of the glomeruli samples were detected using Affymetrix U133A gene chips. Bioinformatic tools were applied to analyze the microarray data. Results of candidate ORG-related genes were further confirmed by real-time quantitative PCR and immunohistochemistry staining using renal biopsy samples of a larger pool of 15 ORG patients. Genes related to lipid metabolism, inflammatory cytokines, and insulin resistance were the most highlighted subgroups that significantly changed in the glomerular gene expression profiles of the ORG patients, compared with the controls. The expression levels of several key genes in lipid metabolism were increased over 2-fold, including low-density lipoprotein receptor, fatty acid binding protein 3, and sterol regulatory element binding protein 1. Moreover, some inflammatory cytokines and their downstream molecules were increased as well, including TNF-alpha and its receptors, IL-6 signal transducer, and interferon-gamma. As the indicators of insulin resistance in the local glomerular cells, levels of glucose-transporter 1, leptin receptor, peroxisome proliferator-activated receptor-gamma, and vascular endothelial growth factor increased, too. In addition to lipid dysmetabolism and insulin resistance, the activation of an inflammatory process in the glomeruli might play a unique role in the development of obesity-related glomerulopathy. Our results expand the understanding of obesity-induced glomerular injuries and shed light on new approaches in the treatment of this disease.