MicroRNA Profiling in Prostate Cancer - The Diagnostic Potential of Urinary miR-205 and miR-214

Prostate cancer (PCa) is the most common type of cancer in men in the United States, which disproportionately affects African American descents. While metastasis is the most common cause of death among PCa patients, no specific markers have been assigned to severity and ethnic biasness of the disease. MicroRNAs represent a promising new class of biomarkers owing to their inherent stability and resilience. In the present study, we investigated potential miRNAs that can be used as biomarkers and/or therapeutic targets and can provide insight into the severity and ethnic biasness of PCa. PCR array was performed in FFPE PCa tissues (5 Caucasian American and 5 African American) and selected differentially expressed miRNAs were validated by qRT-PCR, in 40 (15 CA and 25 AA) paired PCa and adjacent normal tissues. Significantly deregulated miRNAs were also analyzed in urine samples to explore their potential as non-invasive biomarker for PCa. Out of 8 miRNAs selected for validation from PCR array data, miR-205 (p<0.0001), mir-214 (p<0.0001), miR-221(p<0.001) and miR-99b (p<0.0001) were significantly downregulated in PCa tissues. ROC curve shows that all four miRNAs successfully discriminated between PCa and adjacent normal tissues. MiR-99b showed significant down regulation (p<0.01) in AA PCa tissues as compared to CA PCa tissues and might be related to the aggressiveness associated with AA population. In urine, miR-205 (p<0.05) and miR-214 (p<0.05) were significantly downregulated in PCa patients and can discriminate PCa patients from healthy individuals with 89% sensitivity and 80% specificity. In conclusion, present study showed that miR-205 and miR-214 are downregulated in PCa and may serve as potential non-invasive molecular biomarker for PCa.     

马尾松与乡土阔叶树种凋落叶混合分解过程中全碳释放的动态变化

为了调整低山丘陵区低效林林分结构,探明马尾松（Pinus massoniana Lamb.）与乡土阔叶树种凋落叶混合分解过程中的全碳（C）释放规律。本研究以华南广泛分布的马尾松、檫木（Sassafras tzumu（Hemsl.） Hemsl）、香樟（Cinnamomum camphora（Linn） Presl）以及香椿（Toona sinensis（A. Juss.） Roem.）凋落叶为研究对象,将这4个树种凋落叶按照不同树种搭配以及混合比例组合为35个处理后进行野外分解实验,探讨C释放最佳的凋落叶树种组合以及混合比例。研究发现：4个单一树种凋落叶之间,香椿凋落叶的C释放最快,檫木和香樟凋落叶次之,马尾松凋落叶最慢。31个混合凋落叶中,C释放的非加和效应随着分解时间的延长表现出先升增强后减弱的趋势,且相对于其他季节,凋落叶在秋季的非加和效应有所减弱。一针一阔树种组合中,香樟凋落叶占比≥30%的处理：PC73和PC64的协同效应较强;一针两阔和一针三阔组合中,阔叶占比≥30%且含有香椿凋落叶的处理：PST613和712、PCT631和613、PSCT7111和6121的协同效应较强。     

Measurement of free and bound fractions of extracellular ATP in biological solutions using bioluminescence.

Measurement of extracellular ATP in biological solutions is complicated by protein-binding and rapid enzymatic degradation. We hypothesized that the concentration of extracellular ATP could be determined luminometrically by limiting degradation and measuring the free and protein-bound fractions. ATP was added (a) at constant concentration to solutions containing varying albumin concentrations; (b) at varying concentrations to a physiological albumin solution (4 gm/dL); (c) at varying concentrations to plasma. After centrifugation, a fraction of each supernatant was heated. ATP in heated and unheated samples was measured luminometrically. Blood was drawn into saline or an ATP-stabilizing solution and endogenous plasma ATP measured. ATP-albumin binding was a linear function of albumin concentration (3.5% ATP bound at 100 micromol/L to 33.2% ATP bound at 1000 micromol/L) but independent of ATP concentration (29.3%, 10-1000 nmol/L ATP in 602 micromol/L albumin). Heating released the majority of bound ATP from albumin-containing solutions (94.8 +/- 1.7%) and plasma (97.6 +/- 5.1%). Total endogenous plasma ATP comprised 93 +/- 27 nmol/L (free) and 150 +/- 40 nmol/L (total fraction). Without stabilizing solution, degradation of free endogenous plasma ATP occurred. Within a physiological range (10-1000 nmol/L), ATP binds albumin independently of ATP concentration. Heating releases bound ATP, enabling accurate luminometric measurement of total extracellular ATP (free and bound) in biological samples.     

The noncoding RNAs SNORD50A and SNORD50B-mediated TRIM21-GMPS interaction promotes the growth of p53 wild-type breast cancers by degrading p53

Small nucleolar RNA SNORD50A and SNORD50B (SNORD50A/B) has been reported to be recurrently deleted and function as a putative tumor suppressor in different types of cancer by binding to and suppressing the activity of the KRAS oncoproteins. Its deletion correlates with poorer patient survival. However, in this study, we surprisingly found that SNORD50A/B loss predicted a better survival in breast cancer patients carrying wild-type p53. Functional studies showed that SNORD50A/B deletion strongly inhibited the proliferation, migration, invasion and tumorigenic potential, and induced cell cycle arrest and apoptosis in p53 wild-type breast cancer cells, while exerted the opposite effects in p53 mutated breast cancer cells. This was also supported by ectopically expressing SNORD50A/B in both p53 wild-type and mutated breast cancer cells. Mechanistically, SNORD50A/B clearly enhances the interaction between E3 ubiquitin ligase TRIM21 and its substrate GMPS by forming a complex among them, thereby promoting GMPS ubiquitination and its subsequent cytoplasmic sequestration. SNORD50A/B deletion in p53 wild-type breast cancer cells will release GMPS and induce the translocation of GMPS into the nucleus, where GMPS can recruit USP7 and form a complex with p53, thereby decreasing p53 ubiquitination, stabilizing p53 proteins, and inhibiting malignant phenotypes of cancer cells. Altogether, the present study first reports that SNORD50A/B plays an oncogenic role in p53 wild-type breast cancers by mediating TRIM21-GMPS interaction.Subject terms: Cancer genetics, Tumour biomarkers     

P53/PUMA are potential targets that mediate the protection of brain-derived neurotrophic factor (BDNF)/TrkB from etoposide-induced cell death in neuroblastoma (NB)

The over-expressions of brain-derived neurotrophic factor (BDNF) and its tyrosine kinase receptor TrkB have been reported to induce chemo-resistance in neuroblastoma (NB) cells. In this study, we investigated the roles of P53 and BCL2 family members in the protection of BDNF/TrkB from etoposide-induced NB cell death. TB3 and TB8, two tetracycline (TET)-regulated TrkB-expressing NB cell lines, were utilized. The expressions of P53 and BCL2 family members were detected by Western blot or RT-PCR. Transfection of siRNAs was used to knockdown P53 or PUMA. Activated lentiviral was used to over-express PUMA. Cell survival was performed by MTS assay, and the percentage of cell confluence was measured by IncuCyte ZOOM. Our results showed that etoposide treatment induced significant and time-dependent increase of P53, which could be blocked by pre-treatment with BDNF, and knockdown P53 by transfecting siRNA attenuated etoposide-induced TrkB-expressing NB cell death. PUMA was the most significantly changed BCL2 family member after treatment with etoposide, and pre-treatment with BDNF blocked the increased expression of PUMA. Transfection with siRNA inhibited etoposide-induced increased expression of PUMA, and attenuated etoposide-induced NB cell death. We also found that over-expression of PUMA by infection of activated lentiviral induced TrkB-expressing NB cell death in the absence of etoposide, and treatment of BDNF protected NB cells from PUMA-induced cell death. Our results suggested that P53 and PUMA may be potential targets that mediated the protection of BDNF/TrkB from etoposide-induced NB cell death.     

Gratuitous induction of xanthine oxidase by 5,6-diaminouracil in continuously grown cells of Arthrobacter globiformis M4

Summary 5,6-Diaminouracil (DAU), was found to be a gratuitous inducer of xanthine oxidase (XO) in Arthrobacter globiformis M4. Synthesis of urate oxidase was not induced by this compound. Preparation of a biocatalyst rich in XO could be achieved by exposing continuously grown cells to low concentrations of DAU.     

2013年中国侵袭性酵母菌感染流行病学和唑类药物耐药性分析

目的通过对中国侵袭性真菌监测网(CHIF-NET)2013年中国48家综合医院收集的1 562株酵母菌进行流行病学分布及唑类耐药性分析,为临床侵袭性酵母菌的唑类用药提供数据基础。方法收集2013年中国侵袭性真菌监测网48家医院共1 562株酵母菌菌株及其原始信息,采用基质辅助激光解析电离飞行时间质谱(MALDI-TO MS,法国生物梅里埃公司)结合核糖体DNA测序明确菌种鉴定;根据美国临床实验室标准化协会(CLSI)M44-A2纸片扩散法检测菌株对氟康唑及伏立康唑的敏感性。结果本研究共分离出酵母菌1 562株,其中白念珠菌分离率最高(38.4%),其次为近平滑念珠菌复合体(18.4%)、热带念珠菌(16.4%)、光滑念珠菌复合体(9.4%)及其他少见菌种(<6.4%);患者性别中男性占比(60.7%)高于女性(38.9%);患者年龄中,65岁以上年龄段患者最多(34.2%),其次为50~65岁(30.6%)、15~49岁(29.9%)和0~14岁患者(<1.9%);标本来源中以血液标本(46.4%)为主,其次为腹水(10.2%)、导管(9.2%)及引流液(8.5%)、分泌物(5.2%),其他标本类型均较少(<4.7%)。住院患者分离率(93%)显著高于门急诊患者(7%);科室类型中以外科患者(33.8%)为主,其次为重症监护病房(ICU)患者(27.5%)、内科患者(20.5%)及其他病房(<18.2%);药敏结果显示,白念珠菌及近平滑念珠菌复合体对氟康唑及伏立康唑敏感性均较高(>94%),热带念珠菌对氟康唑及伏立康交叉耐药率最高(21.9%),光滑念珠菌复合体交叉耐药率次之(15%),其次为季也蒙念珠菌(8.1%)和菌膜念珠菌(4.3%)。结论应持续加强中国地区侵袭性酵母菌监测,在使用抗菌药物过程中,合理控制其用量,防止耐药率的上升。     

Protective effect of hyperoside against renal ischemia-reperfusion injury via modulating mitochondrial fission,oxidative stress,and apoptosis

Ischemia/reperfusion (IR) is a common cause of acute kidney injury (AKI). However, effective therapies for IR-induced AKI are lacking. Hyperoside is an active constituent in the flowers of Abelmoschus manihot (L.) Medic, which is a traditional Chinese herbal medicine for the treatment of various ischemic brain and heart diseases. Our previous study demonstrated that hyperoside inhibited adriamycin induced podocyte injury both in vivo and in vitro. The aim of this study is to investigate the effect of hyperoside in IR-induced AKI. In mice, pretreatment of hyperoside could markedly attenuate IR-induced AKI, tubular cell apoptosis, and oxidative stress in the kidneys. Meanwhile, we found hyperoside inhibited IR-induced mitochondrial fission by suppressing OMA1 mediated proteolysis of optic atrophy 1 (OPA1). Consistently, in human proximal tubular epithelial cells, hyperoside might inhibit CoCl₂-induced mitochondrial fission, oxidative stress, and apoptosis by regulating OMA1-OPA1 axis. Taken together, our results support the idea that OMA1-OPA1 mediated mitochondrial fission can be used for the prevention of AKI. Hyperoside might have novel therapeutic potential in the treatment of AKI.