Long noncoding RNA TMEM147-AS1 serves as a microRNA-326 sponge to aggravate the malignancy of gastric cancer by upregulating SMAD5

The abnormal expression of long noncoding RNAs (lncRNAs) is frequently observed in gastric cancer (GC) and considered an important driving force in GC progression. However, little is known regarding the involvement of TMEM147-AS1 in GC. Therefore, we examined TMEM147-AS1 expression in GC and determined its prognostic value. In addition, TMEM147-AS1 expression was depleted to identify the functional changes in response to TMEM147-AS1 deficiency. Using the cancer genome atlas dataset and our own cohort, we identified a strong expression of TMEM147-AS1 in GC. Increased TMEM147-AS1 levels in GC showed a significant association with poor prognosis. TMEM147-AS1 interference resulted in the inhibition of GC cell proliferation, colony-forming, migration, and invasion in vitro. Additionally, depletion of TMEM147-AS1 restricted the growth of GC cells in vivo. Mechanistically, TMEM147-AS1 functioned as a microRNA-326 (miR-326) sponge. Furthermore, SMAD family member 5 (SMAD5) was experimentally validated as the functional effector of miR-326. TMEM147-AS1 was demonstrated to sequester miR-326 away from SMAD5; consequently, knocking down TMEM147-AS1 downregulated SMAD5 levels in GC cells. The functional suppression of miR-326 or reintroduction of SMAD5 effectively reversed the attenuated behavior of GC cells caused by TMEM147-AS1 downregulation. In summary, TMEM147-AS1 exhibits tumorigenic activities in GC, which is likely the result of an altered miR-326/SMAD5 axis. Therefore, targeting TMEM147-AS1/miR-326/SMAD5 may represent a target for the treatment of GC.     

沉默GOLPH3基因表达逆转人结肠癌细胞顺铂耐药的研究

背景与目的：化疗是结肠癌的重要治疗方法之一,其方案常含有铂类药物,而化疗耐药会影响结肠癌疗效和预后,其发生机制与基因异常表达有关。高尔基磷酸化蛋白3（Golgi phosphoprotein 3,GOLPH3）是一个癌基因,在结肠癌组织中存在过表达,可促进结肠癌细胞的增殖,与预后不良相关。目前,GOLPH3基因的高表达与结肠癌对铂类耐药的相关性尚不明确。探讨沉默GOLPH3基因逆转人结肠癌HT29细胞对顺铂的化疗耐药效应和机制。方法：HT29细胞分为5组。① 对照组：人结肠癌HT29细胞;② 转染组：siRNA-GOLPH3转染HT29细胞;③ 实验组1：经顺铂处理的HT29细胞;④ 实验组2：经顺铂处理的siRNA-GOLPH3转染HT29细胞;⑤ 实验组3：经顺铂和细胞外调节蛋白激酶（extracellular signal-regulated protein kinases,ERK）1/2抑制剂PD98059处理的HT29细胞。四甲基偶氮唑蓝（methyl thiazolyl tetrazolium,MTT）法、平板克隆形成实验检测各组结肠癌HT29细胞增殖及克隆形成能力。蛋白质印迹法（Western blot）检测GOLPH3、P-糖蛋白（P-glycoprotein,P-gp）、ERK1/2和pERK1/2蛋白的表达。结果：经顺铂处理后,实验组1、实验组2的细胞在波长490 nm处的吸光度（D）值均显著低于对照组（P<0.05）,实验组2的D₄₉₀值显著低于实验组1（P<0.001）;实验组1和实验组2的细胞集落数均显著低于对照组（P<0.01）,实验组2的细胞集落数显著低于实验组1（P<0.001）。实验组1的P-gp、GOLPH3、pERK1/2蛋白表达量显著高于实验组2（P<0.01）;实验组3的P-gp蛋白表达量较实验组1显著降低（P<0.01）。结论：沉默GOLPH3基因可通过抑制丝裂原活化蛋白激酶/细胞外信号调节激酶（mitogen-activated protein kinase/extracellular signal-regulated kinase,MAPK/ERK）信号通路逆转HT29结肠癌细胞对顺铂化疗的耐药性。     

miRNA的研究进展

microRNA又称miRNA,是真核生物细胞中固有的一类不编码蛋白的小分子RNA。生物体中,miRNA能够转录后调控基因的表达,影响着几乎所有的信号通路,参与多种生理病理过程,在肿瘤的发生和发展中也发挥了重要的调节作用。研究miRNA与肿瘤的关系是近年来备受关注的热点之一,其影响肿瘤发生和发展的作用机制将为肿瘤的诊断和治疗提供新的思路。     

Exposure to PM2.5 causes genetic changes in fetal rat cerebral cortex and hippocampus

PM_2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM_2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM_2.5 for extended periods of time and it was found that PM_2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR‐6315, miR‐3588, and miR‐466b‐5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM_2.5 decreased expression of miR‐338‐5p and let‐7e‐5p, both related to mental development. Further, PM_2.5 exposure increased miR‐3560 and let‐7b‐5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR‐99b‐5p, miR‐92b‐5p, and miR‐99a‐5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412–1425, 2017.     

氯沙坦抑制糖基化终末产物刺激培养的人内皮细胞外基质基因的表达

目的 探讨氯沙坦防治糖尿病血管病变的作用机理。方法 用反转录-聚合酶链反应(RT-PCR)和Northern印迹杂交方法测定了0.1～10 μmol·L^-1浓度的氯沙坦对经体外制备的糖基化终末代谢产物（AGEs）处理培养的人脐静脉内皮细胞（HUVECs）转化生长因子（TGF）-β₁和纤连蛋白（FN）基因表达的影响。结果 由AGEs处理的HUVECs TGF-β₁和FN mRNA表达较正常对照组明显增高；与AGEs组相比，TGF-β₁和FN mRNA的表达在氯沙坦1.0 μmol·L^-1时分别降低了29%和23%，10 μmol·L^-1时降低了56%和62%。结论 氯沙坦通过抑制AGEs刺激的内皮细胞TGF-β₁和FN mRNA表达，从而抑制细胞外基质的生成，防止血管重构可能是其防治糖尿病血管并发病的机理之一。     

微小RNA与磷酸化胞外信号调节激酶在视网膜母细胞瘤中的表达及其相关性分析

目的 探讨miRNA和磷酸化胞外信号调节激酶(phosphorylated extracellular signal regulated kinase,P-ERK)在视网膜母细胞瘤(retinoblastoma,Rb)中表达的变化及其相关性.方法 手术切除获取Rb组织标本经组织病理学检查分为低分化、中分化和高分化Rb组织,肿瘤外的正常视网膜组织作为对照组;应用逆转录聚合酶链反应(RT-PCR)技术检测正常视网膜组织和不同分化程度Rb组织中miRNA表达水平,Western blot检测正常视网膜组织和不同分化程度Rb组织中P-ERK蛋白表达情况.结果 Rb组织中miRNA基因表达(低分化0.214±0.140、中分化0.246±0.200、高分化0.256±0.180)、P-ERK蛋白表达(低分化0.367±0.270、中分化0.562±0.190、高分化0.609 ±0.110)明显高于癌旁正常视网膜组织(miRNA:0.200±0.190、P-ERK蛋白:0.211±0.260),差异均有统计学意义(均为P ＜0.05).miRNA、P-ERK蛋白表达与Rb组织分化程度有相关性;miRNA和P-ERK蛋白表达呈正相关.结论 miR-NA和P-ERK蛋白在Rb组织中表达均高于正常视网膜组织,并且二者表达呈正相关.     

Astrocytes in the damaged brain: Molecular and cellular insights into their reactive response and healing potential

Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities.     

依达拉奉对脑缺血再灌注损伤后p-ERK1/2表达的影响

目的:研究依达拉奉对脑缺血再灌注细胞损伤的影响及p-ERK1/2在此过程的作用。方法:将180只雄性ICR小鼠随机分为假手术组、生理盐水治疗组和依达拉奉治疗组。各组于缺血再灌注后分为30min、3h、6h、24h、48h等5个亚组。采用线栓法建立小鼠局灶性脑缺血再灌注模型。治疗组于脑缺血开始及再灌注后12h分别腹腔注射依达拉奉3mg/kg或等量生理盐水,于24h后进行小鼠神经功能学评分;应用免疫组织化学及Westernblot检测p-ERK1/2蛋白表达水平的变化;利用原位缺口末端标记法(TUNEL法)研究神经细胞凋亡的变化。结果:与生理盐水治疗组相比,依达拉奉治疗组小鼠神经行为学评分明显减少(P<0.05);p-ERK1/2免疫阳性细胞及蛋白表达明显减少(P<0.05);凋亡细胞也减少(P<0.05)。结论:依达拉奉能通过抑制与氧化应激有密切关系的p-ERK1/2信号通路显著减轻脑缺血再灌注损伤后神经细胞损伤。     

抗肿瘤药物与miRNA靶点相互作用研究进展

miRNA是一大类非编码的小分子RNA,在肿瘤等许多疾病的发生过程中起重要作用。该文综述了miRNA的生物合成过程以及有关的酶与辅助因子,抗肿瘤药物对miRNA表达的改变以及药物与miRNA靶点的相互作用和机制。同时提出了有关miRNA的功能研究,以miRNA为靶点的药物筛选以及药物对miRNA表达的调控机制是未来研究的重点。     

微小RNA在人髓母细胞瘤中的初步表达分析

目的检测人髓母细胞瘤(MB)与非肿瘤脑组织中微小RNA(miRNA)的表达差异情况,为进一步探讨miRNA参与MB发病的可能分子机制打下基础。方法选取经手术切除的MB组织标本及瘤旁正常小脑组织,分别提取总RNA和小分子RNA,在miRNA微阵列芯片中杂交检测,通过芯片扫描和数据分析,获得该病异常miRNAs表达谱。结果利用miRNA微阵列芯片技术筛选出9个MB的相关miRNAs,其中表达上调4个,表达下调5个。结论miRNA微阵列分析技术是一种快速、高效的研究生物信息的分子生物学技术;筛选出的差异表达miRNAs可能参与MB发病,为此病诊治提供了新的思路,值得进一步研究。