Targeted-gene silencing of BRAF to interrupt BRAF/MEK/ERK pathway synergized photothermal therapeutics for melanoma using a novel FA-GNR-siBRAF nanosystem

Melanoma is significantly associated with mutant BRAF gene, a suitable target for siRNA-based anti-melanoma therapy. However, a tumor-specific delivery system is a major hurdle for clinical applications. Here, we developed a novel nano-carrier, FA-GNR-siBRAF for safe topical application, which consists of folic acid (FA) as the tumor-targeting moiety, golden nanorods (GNR) providing photothermal capability to kill tumor cells under laser irradiation, and siRNA specifically silencing BRAF (siBRAF). The in vitro and in vivo results revealed that FA-GNR-siBRAF displayed high transfection rates, and subsequently induced remarkable gene knockdown of BRAF, resulting in suppression of melanoma growth due to the interruption of the MEK/ERK pathway. Combinatorial photothermal effects and BRAF knockdown by FA-GNR-siBRAF effectively killed tumor cells through apoptosis, with enhanced efficiency than individual treatments. Therefore, the FA-GNR-siBRAF simultaneously induced BRAF gene silencing and photothermal effects which achieved synergistic efficacy in the treatment of melanoma, paving a new path for developing clinical treatment methods for melanoma.     

Pulmonary delivery of polyplexes for combined PAI-1 gene silencing and CXCR4 inhibition to treat lung fibrosis

This report describes the development of polyplexes based on CXCR4-inhibiting poly(ethylenimine) derivative (PEI-C) for pulmonary delivery of siRNA to silence plasminogen activator inhibitor-1 (siPAI-1) as a new combination treatment of pulmonary fibrosis (PF). Safety and delivery efficacy of the PEI-C/siPAI-1 polyplexes was investigated in vitro in primary lung fibroblasts isolated from mice with bleomycin-induced PF. Biodistribution analysis following intratracheal administration of fluorescently labeled polyplexes showed prolonged retention in the lungs. Treatment of mice with bleomycin-induced PF using the PEI-C/siPAI-1 polyplexes resulted in a significant down-regulation of the PAI-1 expression and decreased collagen deposition in the lung. The results of this study provide first evidence of the potential benefits of combined inhibition of CXCR4 and PAI-1 in the pulmonary treatment of PF.     

One year results of presbyLASIK using hybrid bi-aspheric micro-monovision ablation profile in correction of presbyopia and myopic astigmatism

AIM: To observe the effect of inhibiting lncRNA MALAT1 on diabetic neurodegeneration. METHODS: Thirty-six 8-week-old C57BL/6 mice were randomly divided into normal control, diabetic control, diabetic scrambled siRNA and diabetic MALAT1-siRNA groups. After diabetic induction with streptozocin intraperitoneally-injection, the diabetic MALAT1-siRNA group was intravitreally injected with 1 μL 20 μmol/L MALAT1 siRNA, and the diabetic scrambled siRNA group was injected with the same amount of scrambled siRNA. Electroretinography was performed to examine photoreceptor functions 16wk after diabetes induction. MALAT1 expression was detected via RT-PCR. Cone morphological changes were examined using immunofluorescence. Rod morphological changes were examined by determining outer nuclear layer thickness. RESULTS: Retinal MALAT1 expression was upregulated in the diabetic control group, while MALAT1 expression in the diabetic MALAT1-siRNA group was decreased by 91.48% compared to diabetic control group. The diabetic control and diabetic MALAT1-siRNA groups showed lower a-wave and b-wave amplitudes than did the normal control group in scotopic and photopic electroretinogram, while the diabetic MALAT1-siRNA group showed higher amplitudes than diabetic control group. Morphological examination revealed that outer nuclear layer thickness in the diabetic MALAT1-siRNA and diabetic control groups was lower than normal control group. However, outer nuclear layer thickness was greater in the diabetic MALAT1-siRNA group than diabetic control group. Moreover, the diabetic control group showed a sparser cone cell arrangement and shorter outer segment morphology than diabetic MALAT1-siRNA group. CONCLUSION: Inhibiting retinal MALAT1 results in protective effects on the function and morphology of photoreceptors, thus alleviating diabetic neurodegeneration.     

HEF1对神经胶质瘤细胞U251的增殖﹑凋亡、侵袭和迁移的研究

目的：探讨HEF1对神经胶质瘤细胞U251增殖、凋亡、侵袭和迁移影响情况。方法通过RT-PCR、Western Blot检测脑组织正常标本与胶质瘤细胞U251中HEF1的表达水平,化学合成HEF1基因小干扰RNA（siRNA）下调其基因表达,检测siRNA对U251细胞的生物学行为的影响。MTT法、Transwell、Hochest染色分别检测细胞的增殖、侵袭、迁移、凋亡。结果HEF1基因在正常脑组织标本中的表达水平明显低于胶质瘤细胞。与对照组相比,干扰HEF1的表达,神经胶质瘤细胞U251增殖、侵袭和迁移能力受到显著抑制,细胞凋亡明显增强。结论HEF1促进神经胶质瘤恶性增殖及侵袭,抑制细胞凋亡,有可能成为分子治疗有效靶点。     

小干扰RNA 抑制Pokemon表达对肺癌细胞A549和食管癌细胞EC109 增殖的影响

目的：探讨Pokemon特异性小干扰RNA对肺癌细胞A549和食管癌细胞EC109 增殖的影响.方法：瞬时转染Pokemon特异性小干扰RNA至肺癌细胞A549和食管癌细胞EC109,RT-PCR、Western Blot技术检测转染后细胞中Pokemon的mRNA和蛋白表达水平,检测细胞的增殖及细胞周期变化.结果：与空白组和阴性对照组相比,瞬时转染Pokemon小干扰RNA后,肺癌细胞A549和食管癌细胞EC109中Pokemon的mRNA水平均下降至25%～35%,蛋白水平亦明显下降.细胞增殖能力在培养24,48,72 h均显著降低（P＜0.05）.细胞周期分析显示转染Pokemon小干扰RNA后S期的比例显著高于siRNA阴性对照组（A549细胞：55.7%±2.5% vs 42.7%±0.6%,P＜0.01;EC109细胞：67.7%±2.5% vs 52.0%±2.0%,P＜0.01）.G1期的比例显著低于siRNA阴性对照组（A549细胞：33.0%±2.0% vs 45.3%±1.5%,P＜0.01;EC109细胞：30.7%±1.2% vs 44.0%±1.7%,P＜0.01）.两种细胞均阻滞于S期.结论：Pokemon小干扰RNA可抑制肺癌细胞A549和食管癌细胞EC109 的增殖.     

Mig-2 attenuates cisplatin-induced apoptosis of human glioma cells in vitro through AKT/JNK and AKT/p38 signaling pathways

Aim:

Mig-2 (also known as Kindlin-2 and FERMT2) is an important regulator of integrin activation and cell-extracellular matrix adhesion, and involved in carcinogenesis and tumor progression. The aim of this study was to investigate the role of mig-2 in cisplatin-induced apoptosis of human glioma cells in vitro.

Methods:

The expression of mig-2 was modulated in human glioma H4, HS 683 and U-87 MG cells by transfection with a plasmid carrying mig-2 or mig-2 siRNA. Cisplatin-induced apoptosis was detected using Annexin V/PI staining and flow cytometry, as well as MTS analyses. The expression of apoptosis-related or signaling proteins was examined using Western blotting analysis. H4 cells were transfected with plasmids carrying mig-2 mutants to determine the functional domain of mig-2.

Results:

In the 3 glioma cell lines tested, overexpression of mig-2 significantly attenuated cisplatin-induced apoptosis, whereas knock-down of mig-2 potentiated the apoptosis. The mechanisms of action of mig-2 were further addressed in H4 cells: overexpression of mig-2 markedly reduced cleaved caspase-9, caspase-8, caspase-3 and PARP, as well as p-JNK and p-p38, and increased p-AKT in cisplatin-treated H4 cells, whereas mig-2 siRNA reversely changed these apoptosis-related and signaling proteins. Furthermore, pretreatment with JNK inhibitor SP600125 and p38 inhibitor SB203580, or with AKT inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002 abolished the effects of mig-2 on cisplaxtin-induced apoptosis. In H4 cells, GFP-mig-2 F3 plasmid that contained only the F3 subdomain showed the same efficiency in attenuating cisplatin-induced apoptosis, as the mig-2 wild-type vector did, whereas GFP-mig-2 (1-541) plasmid that lacked the F3 subdomain was inactive.

Conclusion:

Mig-2 significantly attenuates the antitumor action of cisplatin against human glioma cells in vitro through AKT/JNK and AKT/p38 signaling pathways. The F3 subdomain of mig-2 is necessary and sufficient for this effect.     

The Role of Sodium-Dependent Glucose Transporter 1 and Glucose Transporter 2 in the Absorption of Cyanidin-3-O-β-Glucoside in Caco-2 Cells

Anthocyanins have multiple biological activities of benefit to human health. While a few studies have been conducted to evaluate the bioavailability of anthocyanins, the mechanisms of their absorption mechanism remain ill-defined. In the present study, we investigated the absorption mechanism of cyanidin-3-O-β-glucoside (Cy-3-G) in human intestinal epithelial (Caco-2) cells. Cy-3-G transport was assessed by measuring the absorptive and efflux direction. Inhibition studies were conducted using the pharmacological agents, phloridzin, an inhibitor of sodium-dependent glucose transporter 1 (SGLT1), or phloretin, an inhibitor of glucose transporter 2 (GLUT2). The results showed that phloridzin and phloretin significantly inhibited the absorption of Cy-3-G. In addition, Caco-2 cells transfected with small interfering RNA (siRNA) specific for SGLT1 or GLUT2 showed significantly decreased Cy-3-G absorption. These siRNA transfected cells also showed a significantly decreased rate of transport of Cy-3-G compared with the control group. These findings suggest that Cy-3-G absorption is dependent on the activities of SGLT1 and GLUT2 in the small intestine and that SGLT1 and GLUT2 could be a limiting step for the bioavailability of Cy-3-G.     

Protein kinase C isoforms in atherosclerosis: Pro- or anti-inflammatory?

Atherosclerosis is a pathologic condition caused by chronic inflammation in response to lipid deposition in the arterial wall. There are many known contributing factors such as long-term abnormal glucose levels, smoking, hypertension, and hyperlipidemia. Under the influence of such factors, immune and non-immune effectors cells are activated and participate during the progression of atherosclerosis. Protein kinase C (PKC) family isoforms are key players in the signal transduction pathways of cellular activation and have been associated with several aspects of the atherosclerotic vascular disease. This review article summarizes the current knowledge of PKC isoforms functions during atherogenesis, and addresses differential roles and disputable observations of PKC isoforms. Among PKC isoforms, both PKCβ and PKCδ are the most attractive and potential therapeutic targets. This commentary discusses in detail the outcomes and current status of clinical trials on PKCβ and PKCδ inhibitors in atherosclerosis-associated disorders like diabetes and myocardial infarction. The risk and benefit of these inhibitors for clinical purposes will be also discussed. This review summarizes what is already being done and what else needs to be done in further targeting PKC isoforms, especially PKCβ and PKCδ, for therapy of atherosclerosis and atherosclerosis-associated vasculopathies in the future.     

Lysophosphatidic acid-induced IL-8 secretion involves MSK1 and MSK2 mediated activation of CREB1 in human fibroblast-like synoviocytes

Lysophosphatidic acid (LPA) is a pleiotropic lipid mediator that promotes motility, survival, and the synthesis of chemokines/cytokines such as interleukin-8 (IL-8) and interleukin-6 by human fibroblast-like synoviocytes from patients with rheumatoid arthritis (RAFLS). In those cells LPA was reported to induce IL-8 secretion through activation of various signaling pathways including p38 mitogen-activated protein kinase (p38 MAPK), p42/44 MAPK, and Rho kinase. In addition to those pathways we report that mitogen- and stress-activated protein kinases (MSKs) known to be activated downstream of the ERK1/2 and p38 MAPK cascades and CREB are phosphorylated in response to LPA. The silencing of MSKs with small-interfering RNAs and the pharmacological inhibitor of MSKs SB747651A shows a role for both MSK1 and MSK2 in LPA-mediated phosphorylation of CREB at Ser-133 and secretion of IL-8 and MCP-1. Whereas CREB inhibitors have off target effects and increased LPA-mediated IL-8 secretion, the silencing of CREB1 with short hairpin RNA significantly reduced LPA-induced chemokine production in RAFLS. Taken together the data clearly suggest that MSK1 and MSK2 are the major CREB kinases in RAFLS stimulated with LPA and that phosphorylation of CREB1 at Ser-133 downstream of MSKs plays a significant role in chemokine production.     

siRNA沉默DNA聚合酶β基因表达对食管癌EC9706细胞放疗敏感性的影响

目的探讨siRNA沉默DNA聚合酶β（polβ）基因表达对食管癌EC9706细胞放疗敏感性的影响。方法利用脂质体将siRNA转染至EC9706细胞,采用实时荧光定量PCR检测3组不同转染的细胞中polβ mRNA的表达变化;不同剂量（0、2、4、6、8 Gy）照射3组细胞,CCK8方法检测各组细胞的存活率;用3 Gy照射,流式细胞术检测每组细胞的凋亡率。结果转染沉默polβ组polβ基因表达水平显著降低（P〈0.01）;CCK8检测结果显示,随着照射剂量的增加,细胞存活率呈下降趋势,其中沉默polβ组细胞存活率显著低于两个对照（P〈0.05）;沉默polβ组细胞凋亡率显著高于无关siRNA组或空白对照组（P〈0.01）,照射后沉默polβ组细胞的凋亡率增加量显著高于无关siRNA组和空白对照组（P〈0.01）。结论沉默食管癌细胞polβ基因表达可增加其对放疗的敏感性。