Clinical Diagnostic Implications of Body Fluid MiRNA in Oral Squamous Cell Carcinoma: A Meta-Analysis

Oral cancer, predominantly oral squamous cell carcinoma (OSCC), is one of the most leading causes of cancers worldwide. Due to a low 5-year survival rate, highly effective methods for the early detection of OSCC are totally needed. MicroRNAs (miRNAs), as promising biomarkers, can bring insights into tumorigenesis of oral cancers. However, studies on the accuracy of miRNAs detection in OSCC have inconsistent conclusions, leading us to conduct this meta-analysis. The aim of this study was to systematically review the articles investigating the diagnostic value of miRNAs in OSCC.The PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), Web of Science were searched (updated to June 11th, 2015) to identify all articles evaluating the diagnostic yield of miRNAs for OSCC. The pooled sensitivity, specificity, and other diagnostic parameters were used to assess the performance of miRNAs assays on OSCC detection. Statistical analysis was conducted by employing the R software.The present meta-analysis comprised 23 studies from 10 articles, including 598 OSCC patients and 320 healthy individuals, available for analysis. The summary receiver operator characteristic (SROC) curve was plotted. Meanwhile, the pooled diagnostic parameters and the area under curve (AUC) were calculated based on all included studies. The pooled diagnostic parameters calculated from all 23 studies were as follows: pooled sensitivity of 0.759 (95% CI: 0.701–0.809), pooled specificity of 0.773 (95% CI: 0.713–0.823) and AUC of 0.832, which indicates a relatively high diagnostic accuracy of miRNAs in differentiating OSCC patients from healthy controls. Meanwhile, In addition, subgroup analyses were conducted to access the heterogeneity between studies, which is based on specimen (serum/plasma/blood/saliva/ tissue) and ethnicity (Asian/Caucasian).In summary, our meta-analysis suggests that miRNAs might be used in noninvasive screening tests for OSCC, which needs further large-scale studies to be validated.     

Neutralization of Mitochondrial Superoxide by Superoxide Dismutase 2 Promotes Bacterial Clearance and Regulates Phagocyte Numbers in Zebrafish

Mitochondria are known primarily as the location of the electron transport chain and energy production in cells. More recently, mitochondria have been shown to be signaling centers for apoptosis and inflammation. Reactive oxygen species (ROS) generated as by-products of the electron transport chain within mitochondria significantly impact cellular signaling pathways. Because of the toxic nature of ROS, mitochondria possess an antioxidant enzyme, superoxide dismutase 2 (SOD2), to neutralize ROS. If mitochondrial antioxidant enzymes are overwhelmed during severe infections, mitochondrial dysfunction can occur and lead to multiorgan failure or death. Pseudomonas aeruginosa is an opportunistic pathogen that can infect immunocompromised patients. Infochemicals and exotoxins associated with P. aeruginosa are capable of causing mitochondrial dysfunction. In this work, we describe the roles of SOD2 and mitochondrial ROS regulation in the zebrafish innate immune response to P. aeruginosa infection. sod2 is upregulated in mammalian macrophages and neutrophils in response to lipopolysaccharide in vitro, and sod2 knockdown in zebrafish results in an increased bacterial burden. Further investigation revealed that phagocyte numbers are compromised in Sod2-deficient zebrafish. Addition of the mitochondrion-targeted ROS-scavenging chemical MitoTEMPO rescues neutrophil numbers and reduces the bacterial burden in Sod2-deficient zebrafish. Our work highlights the importance of mitochondrial ROS regulation by SOD2 in the context of innate immunity and supports the use of mitochondrion-targeted ROS scavengers as potential adjuvant therapies during severe infections.     

lncRNAPCGEM1对肺癌A549细胞恶性生物学行为的影响及其作用机制

目的：探讨长链非编码RNA（long-chain noncoding，lncRNA）PCGEM1 对肺癌A549 细胞恶性生物学行为的影响及其作用机制。方法：收集2016 年3 月至2018 年5 月湖北医药学院附属太和医院胸外科接受手术治疗的62 例肺癌（lung cancer，LC）患者癌组织及相应的癌旁组织标本，并用以上组织构建LC组织芯片。用qPCR检测lncRNA PCGEM1 及miR-148a 在LC组织相应的癌旁组织及LC细胞株中的表达。构建lncRNA PCGEM1 沉默细胞系A549-siPCGEM1 和阴性对照A549-NC，并以A549 细胞作为空白对照（Control 组），用MTT和平板克隆实验检测敲减PCGEM1 对A549 细胞增殖能力的影响，Transwell 和划痕实验检测敲减PCGEM1 对A549 细胞侵袭和迁移能力的影响。使用生物信息学网站StarBase 预测可互补结合PCGEM1的miRNA，再根据Targetscan 网站预测相应可靶向结合miRNA的基因；Western blotting 实验检测TGF-β2/Smad2 信号通路蛋白表达情况。结果：在LC组织中PCGEM1 的表达水平高于癌旁组织而miR-148a 的表达量明显低于癌旁组织（均P<0.05），PCGEM1 在5 种LC细胞株中的表达明显高于人肺成纤维细胞HLF-02（均P<0.05），且以A549 细胞中表达最高。敲减PCGEM1 后，与Control 组和A549-NC 组比较，A549-siPCGEM1 组A549 细胞增殖、侵袭和迁移能力显著降低（均P<0.05）。StarBase 和Targetscan 网站预测结果显示，PCGEM1 可与miR-148a 互补结合，miR-148a 与TGF-β2 存在靶向结合位点。与Control 组和A549-NC组比较，A549-siPCGEM1 组中miR-148a 表达明显升高，TGF-β2 及p-Smad2 蛋白的表达明显降低（均P<0.05）。结论：lncRNA PCGEM1在LC组织和细胞株中高表达，高表达的PCGEM1 可通过下调miR-148a 水平强化TGF β2/Smad2 信号通路，从而促进A549 细胞恶性生物学行为的进展。