目的 研究靶向低密度脂蛋白受体蛋白1(LRP1)的载药嵌段共聚物(ANPs/CPT)对胶质瘤细胞的增殖抑制和促进凋亡的作用.方法 采用Western blotting技术检测LRP1在大鼠胶质瘤细胞(C6细胞)和脑毛细血管内皮细胞(BCECs)的表达水平.用激光共聚焦显微镜测定C6细胞和BCECs对Angiopep-2修饰的靶向未载药嵌段共聚物(ANPs)和非靶向对照NPs的摄取量;采用噻唑蓝(MTT)比色法检测ANPs/CPT抑制C6细胞和BCECs增殖的作用;采用流式细胞仪分析不同CPT终浓度(10μg/mL,20 μg/mL)的ANPs/CPT促C6细胞凋亡作用.结果 LRP1在C6和BCECs细胞膜表面高表达.C6细胞对ANPs的摄取量显著高于NPs(P ＜0.01);ANPs/CPT对C6细胞的增殖抑制作用显著高于NPs/CPT(P ＜0.05),但对BCECs的增殖抑制作用与NPs/CPT无显著差异(P＞0.05).CPT终浓度10 μg/mL、20 μg/mL的ANPs/CPT与NPs/CPT作用于C6细胞48 h后的凋亡率分别为(16.1 ±0.9)％、(30.4±1.1)％和(18.8±0.9)％、(40.3±1.2)％,差异均有统计学意义(均P＜0.05).结论 ANPs/CPT有显著的靶向抑制胶质瘤细胞增殖及促进其凋亡的作用,具有潜在的治疗胶质瘤的应用价值.

The development of valuable theranostic agents for overcoming the blood-brain barrier (BBB) to achieve efficient imaging-guided glioma-targeting delivery of therapeutics remains a great challenge for personalized glioma therapy. We herein developed a novel functional star-shaped polyprodrug amphiphile (denoted as CPP-2) via a combination of successive reversible addition-fragmentation chain transfer (RAFT) polymerization and click functionalization. In a diluted solution, the star amphiphile existed as structurally stable unimolecular micelles, containing hydrophobic cores conjugated with reduction-responsive camptothecin prodrugs Camptothecin (CPT) prodrug monomer (CPTM) and a tertiary amine monomer (2-(diethylamine) ethyl methacrylate, DEA) and hydrophilic oligo-(ethylene glycol) monomethyl ether methacrylat (OEGMA) outer coronas covalently decorated with dual-targeting moieties Angiopep2 (ANG) and small magnetic resonance imaging (MRI) contrast agents DOTA-Gd. In vitro and in vivo data in this study demonstrated that the ANG-modified micelles were capable of efficiently penetrating the BBB and delivering loaded cargoes such as CPT and Gd3+ contrast agents to glioma cells, leading to a considerably enhanced t1 relaxivity as well as antiglioma efficacy. Simultaneously, the targeted antiglioma efficacy and noninvasive MR imaging for a visualized therapy were realized. These collective findings augured well for the star polyprodrug amphiphiles to be utilized as a novel theranostic platform for clinical application in glioma therapy.

Activation of inflammatory signaling pathways is of central importance in the pathogenesis of alcoholic liver disease (ALD) and nonalcoholic steatohepatitis (NASH). Nod-like receptors (NLRs) are intracellular innate immune sensors of microbes and danger signals that control multiple aspects of inflammatory responses. Recent studies demonstrated that NLRs are expressed and activated in innate immune cells as well as in parenchymal cells in the liver. For example, NLRP3 signaling is involved in liver ischemia-reperfusion (I/R) injury and silencing of NLRP3 can protect the liver from I/R injury. In this article, we review the evidence that highlights the critical importance of NLRs in the prevalent liver diseases. The significance of NLR-induced intracellular signaling pathways and cytokine production is also evaluated.

As a transcription factor, zinc finger E-box binding homeobox 2 (ZEB2) includes multiple functional domains which interact with kinds of transcriptional co-effectors. It has been reported that ZEB2 was involved in signal transduction and multiple cellular functions. However, the functional role of ZEB2 in inflammation is still obscure. The aim of the current study is to explore the function of ZEB2 in inflammation cytokine secretion and the role of the nuclear factor-κB (NF-κB) signaling pathway in lipopolysaccharide (LPS)-induced human proximal tubule cell line (HK-2) cells. Our result demonstrated that expression of ZEB2 was significantly downregulated and expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was upregulated in response to LPS. Meanwhile, knockdown of ZEB2 by transfecting siRNA increased TNF-α and IL-6 secretion. Overexpression of ZEB2 resulted in a decrease of TNF-α and IL-6 secretion in HK-2 cells. Additionally, Western blot analysis indicated that ZEB2 suppressed the activation of the NF-κB signaling pathway via downregulating the levels of phosphorylated p65 and IκBα compared with LPS stimulation. Collectively, our data demonstrated that ZEB2 attenuated LPS-induced inflammation cytokine secretion possibly through suppressing the NF-κB signaling pathway.

During the liver fibrosis recovery stage tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can effectively induce apoptosis of activated hepatic stellate cells (HSCs). Normal hepatic stellate cells are resistant to TRAIL cytotoxicity. Therefore, enhancing the sensitivity of TRAIL-induced apoptosis of HSCs may be useful to treat hepatic fibrogenesis. Here, we demonstrated that miR-145 and TRAIL were down-regulated in both liver fibrosis tissue samples and transforming growth factor-β1 induced HSCs, concomitant with increased the expression of ZEB2. In addition, we found that mimics-mediated over-expression of miR-145 led to resistance to the ZEB2 expression and up-regulation of the TRAIL-induced apoptosis after treatment of LX-2 cells with TRAIL. Furthermore, ZEB2-siRNA transfected LX-2 cells showed the increased sensitivity to TRAIL-induced apoptosis. Whereas, opposite results were obtained in miR-145-inhibitor group or ZEB2 plasmid group. Moreover, miR-145 regulated ZEB2 gene expression by specifically interacting with the 3′-UTR of ZEB2 mRNA to inhibit the expression of ZEB2. Further studies showed that the over-expression of ZEB2 could inhibit TRAIL-induced apoptosis via inhibiting nuclear factor-κB (NF-κB) signaling pathway in LX-2 cells. Collectively, our data suggest that up-regulation of miR-145 can down-regulate ZEB2 expression, consequently promoting TRAIL-induced apoptosis in LX-2 cells through NF-κB signaling pathway, which facilitates the resolution of liver fibrosis.

MicroRNAs (miRNAs) are involved in the pathogenesis of various human cancers. Here we show that miR-145 expression is decreased in human glioma samples, rat glioma tissues, and glioma cell lines, while expression of BNIP3 is increased. Over-expression of miR-145 or suppression of BNIP3 induced glioma cell apoptosis. BNIP3 is localized in the nucleus in glioma cells, and miR-145 inhibits BNIP3 expression by binding to the 3’ untranslated region of its mRNA. Interestingly, miR-145 and BNIP3 regulate glioma cell apoptosis by modulating Notch signaling. These results indicate that miR-145 increases glioma cell apoptosis by inhibiting BNIP3 and Notch signaling, and suggest that miR-145 may serve as a novel therapeutic target for malignant glioma.

Manipulating the posttranslational modulator of p53 is central in the regulation of its activity and function. ISGylated p53 can be degraded by the 20S proteasome. During this process, HERC5/Ceb1, an IFN-induced HECT-type E3 ligase, mediated p53 ISGylation. In this study, we indicated that HERC5 was over-expressed in both HCC tissue samples and cell lines. Knockdown of HERC5 significantly induced the expression of p53, p21 and Bax/Bcl-2 in HCC cells, resulting in apoptosis augment. Whereas, opposite results were obtained by using HERC5 over-expression. On this basis, we screened a 7, 11-disubstituted quinazoline derivative HZ-6d that could bind to the HERC5 G-rich sequence in vitro. Interestingly, HZ-6d injection effectively delayed the growth of xenografts in nude mice. In vitro, HZ-6d significantly inhibited cell growth, suppressed cell migration, induced apoptosis in HCC cells. Further studies demonstrated the anti-cancer effect of HZ-6d was associated with down-regulation of HERC5 and accumulation of p53. Collectively, we demonstrated that HZ6d is a HERC5 G-quadruplex ligand with anti-tumor properties, an action that may offer an attractive idea for restoration of p53 function in cancers.

The activation of hepatic stellate cells (HSCs) plays a critical role in the development of liver fibrosis. The induction of apoptosis in activated HSCs during the recovery phase of hepatic fibrosis represents a potential anti-fibrotic therapy. We have previously shown that Smad2 protects against hepatic fibrogenesis; however, the role of Smad2 in the regulation of activated HSC apoptosis remains unknown. We hypothesized that Smad2 regulates the apoptosis of activated HSCs, leading to the resolution of liver fibrosis. To test this hypothesis, the livers of rats were harvested at 0 and 4weeks after hepatic fibrosis was established by CCl4 injection. Furthermore, TGF-β1-activated HSCs were treated with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) following the silencing or overexpression of Smad2. Both the phosphorylation of Smad2 and TRAIL were detected in fibrotic liver tissues. The results of TUNEL and α-SMA double-staining showed an increase in the apoptosis of activated HSCs during the spontaneous recovery phase. The knockdown of Smad2 reduced TRAIL-induced apoptosis in TGF-β1-activated human LX-2 cells and resulted in an increased expression of α-SMA and collagen I (Col. I). In contrast, the overexpression of Smad2 increased TRAIL-induced HSC apoptosis and reduced the expression of α-SMA and Col. I. The mechanisms underlying these findings were associated with the Smad2-mediated down-regulation of X-linked inhibitor of apoptosis protein (XIAP), resulting in enhanced caspase-3 activity and apoptosis. In conclusion, Smad2 enhances TRAIL-induced apoptosis in activated HSCs, which facilitates the resolution of hepatic fibrosis.

The activation of hepatic stellates cells (HSCs) is well believed to play a pivotal role in the development of liver fibrosis. MicroRNA-145 (miR-145) is known to suppress the progression of hepatocellular carcinoma, and is previously reported to be associated with Wnt/β-catenin pathway, but its role in the progression of hepatic fibrosis and activation of HSCs remains unknown and is warranted for investigation. In the present study, we found that the expression of miR-145 is significantly down-regulated in vivo in CCl4-induced mice liver fibrosis as well as in transforming growth factor-β1 (TGF-β1) induced HSC-T6 cell lines and human hepatic stellate cell line LX-2 in vitro. Furthermore, over-expression of miR-145 inhibited TGF-β1-induced the activation and proliferation of HSC-T6 cells in vitro. Mechanistically, we identified that zinc finger E-box-binding homeobox 2 (ZEB2), a key mediator of epithelial-to-mesenchymal transition, acted as a functional downstream target for miR-145. Interestingly, ZEB2 was shown to be involved in the TGF-β1-induced HSCs activation by regulating Wnt/β-catenin signaling pathway. Taken together, our results revealed the critical regulatory role of miR-145 in HSCs activation and implied miR-145 as a potential candidate for therapy of hepatic fibrosis by regulation of Wnt/β-catenin through targeting ZEB2.