[Mechanism of Panax notoginseng saponins in treating diabetic kidney disease based on network pharmacology and experimental verification].

This study aims to investigate the therapeutic effect and mechanism of Panax notoginseng saponins(PNS) on diabetic kidney disease(DKD) based on network pharmacology, molecular docking, animal experiments. Network pharmacology was employed to screen the potential targets, and STRING was employed to build the protein-protein interaction network. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were carried out for the core targets screened out, and a ″components-targets-pathways″ visualization network was constructed to predict the potential mechanism of PNS in treating DKD. Five active ingredients were screened from PNS, the core targets of which for treating DKD were AKT1, STAT3, ESR1, HSP90AA1, MTOR, et al. The KEGG enrichment analysis showed that the pathways related to PNS for treating DKD included the pathway in cancer, chemical carcinogenesis-receptor activation, and PI3K-AKT signaling pathway. GO analysis revealed that protein binding, homologous protein binding, enzyme binding, and ATP binding were the main biological processes involved in the treatment of DKD with PNS. Male 6-week-old db/db mice were randomized into model, dapagliflozin, and low-dose and high-dose PNS groups, with 10 mice in each group. Ten 6-week-old db/m mice were used as the control group. Mice were administrated with corresponding drugs or distilled water(control and model groups) by gavage once a day for 8 weeks. The body weight, fasting blood glucose, kidney index, microalbuminuria, creatinine, microalbuminuria/creatinine ratio, and urea nitrogen content in the urine of mice were determined. Hematoxylin-eosin(HE) staining, periodic acid-Schiff(PAS) staining, and Masson staining were performed to observe the protective effect of PNS on the renal tissues in db/db mice. The results showed that PNS could significantly reduce the fasting blood glucose level and improve the renal damage in db/db mice. Western blot results showed that PNS down-regulated the protein levels of p-AKT1 and p-STAT3 and decreased the p-AKT1/AKT1 and p-STAT3/STAT3 ratios. In addition, high-dose PNS down-regulated the protein level of PIK3CA. In conclusion, PNS may exert the kidney-protecting effects in DKD by inhibiting STAT3 via the PI3K-AKT signaling pathway.

Fine-Structural Morphology of the Mouthparts of the Polyphagous Invasive Planthopper, Ricania speculum (Walker) (Hemiptera: Fulgoromorpha: Ricaniidae).

Mouthparts are the crucial sensory and feeding organs associated with food detection and feeding in insects. The Asian ricaniid planthopper Ricania speculum (Walker), recently introduced into Europe, can cause severe economic damage by sucking the phloem sap of tea, camphor, citrus, black locust and other plants using piercing-sucking mouthparts. To facilitate comprehensive understanding of feeding mechanisms in the Ricaniidae, the fine structure of the mouthparts of Ricania speculum was observed by scanning electron microscopy for the first time. The mouthparts are tubular, consist of a cone-shaped labrum, with a wrinkled epidermis and without sensilla; the tubular labium is divided into three segments: a slender stylet fascicle consisting of two mandibular stylets with four ridged processes and a row of longitudinal striations on the distal part of the outer surface; and two maxillary stylets with a smooth and sharp distal part, interlocked to form a larger food canal and a smaller salivary canal. On the labium, 15 kinds of sensilla of different functions were recognized. Two rows of short sensilla basiconica (SB I) are symmetrically distributed along the labial groove on the first segment. Two pairs of long sensilla basiconica (SB II) (proprioceptors) are on both sides of the labial groove at the junction of the second and third segments. A placoid, flattened sensillum (SPF) is symmetrically located laterally on the proximal end of the last segment and several flattened sensilla campaniformia (SFC) were visible on the ventral side on the second and third segments. The distribution of four types (I-IV) of sensilla cheatica of different lengths on the dorsal surface of the labium is significantly denser than on the lateral and ventral surfaces. The labial apex is divided into dorsal and ventral sensory fields, mainly including uniporous long peg sensilla (I), as well as smaller peg sensilla (II) and nonporous peg sensilla (PGSN) on each dorsal field. These nonporous sensilla basiconica (BSN I and III) occur on the ventral sensory fields and are constant in number and distribution. The nonporous sensilla basiconica (BSN II) are symmetrically arranged near the opening of the stylet fascicle similarly to two oval multiporous plate sensilla (OPSM). The sensilla arrangement is slightly different from that observed in previously studied Fulgoromorpha using scanning electron micrographs, which may reflect differences in feeding preference or behavior.

The olive constituent oleuropein exerts nephritic protective effects on diabetic nephropathy in db/db mice.

BACKGROUND: Oleuropein, the most prevalent polyphenol in olives, exerts many positive impacts on human health, including counteracting cancer. However, the effect of oleuropein on diabetic nephropathy (DN) progression remains elusive. METHODS: A total of three groups of mice were used in our study. Two groups of db/db mice fed with or without oleuropein. A group of wide-type mice fed with normal diet was used as normal control. After ten weeks of treatment, the body weight, biochemical parameters, oxidative stress markers, inflammatory cytokines levels, and kidney injury status were measured. RESULTS: Our results demonstrated that oral administration of oleuropein reduced body weight, alleviated kidney injury, and decreased oxidative stress and inflammatory response in db/db mice. The oleuropein inhibited cell apoptosis via regulation of MAPK signalling pathways and its downstream targets Bax, caspase-3, and Bcl-2 expression. CONCLUSION: Oleuropein may server as a favourable additional agent for the treatment of patients with DN.

TLR4 knockout ameliorates streptozotocin-induced osteoporosis in a mouse model of diabetes.

Type 1 diabetes mellitus (T1DM) is characterized by hyperglycemia manifesting as insufficient insulin. Toll-like receptor-4 (TLR4) has been implicated in diabetic osteoporosis. We established streptozotocin (STZ)-induced diabetic mouse model and examined the relevant osteoporosis factors in different experimental groups, the WT-CON group, WT-STZ group, KO-CON group and KO-STZ group, respectively. No obvious protection of TLR4 deletion was shown in mice with diabetes. There was no obvious difference in the body weight or blood glucose concentration between WT-STZ group and KO-STZ group. However, TLR4 deletion reduced the receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation. Furthermore, TLR4 knockout attenuated STZ-induced diabetic osteoporosis via inhibiting osteoblasts and pre-inflammation factors mediated by the NF-κB pathway. TLR4 deletion ameliorated STZ-induced diabetic osteoporosis in mice, and TLR4 may be used as a potential therapeutic target for the treatment of diabetic osteoporosis.

Helper virus-free gutless adenovirus (HF-GLAd): a new platform for gene therapy.

Gene therapy is emerging as a treatment option for inherited genetic diseases. The success of this treatment approach greatly depends upon gene delivery vectors. Researchers have attempted to harness the potential of viral vectors for gene therapy applications over many decades. Among the viral vectors available, gutless adenovirus (GLAd) has been recognized as one of the most promising vectors for in vivo gene delivery. GLAd is constructed by deleting all the viral genes from an adenovirus. Owing to this structural feature, the production of GLAd requires a helper that supplies viral proteins in trans. Conventionally, the helper is an adenovirus. Although the helper adenovirus efficiently provides helper functions, it remains as an unavoidable contaminant and also generates replicationcompetent adenovirus (RCA) during the production of GLAd. These two undesirable contaminants have raised safety concerns and hindered the clinical applications of GLAd. Recently, we developed helper virus-free gutless adenovirus (HF-GLAd), a new version of GLAd, which is produced by a helper plasmid instead of a helper adenovirus. Utilization of this helper plasmid eliminated the helper adenovirus and RCA contamination in the production of GLAd. HF-GLAd, devoid of helper adenovirus and RCA contaminants, will facilitate its clinical applications. In this review, we discuss the characteristics of adenoviruses, the evolution and production of adenoviral vectors, and the unique features of HF-GLAd as a new platform for gene therapy. Furthermore, we highlight the potential applications of HF-GLAd as a gene delivery vector for the treatment of various inherited genetic diseases. [BMB Reports 2020; 53(11): 565-575].

Different Imaging Features of Retroperitoneal Unicentric Castleman's Disease: A Case Report.

Castleman's disease is a rare disease which is difficult to diagnose early due to its lack of specific manifestations, and also is easily confused with lymphoma or other solid tumors. Castleman's disease can occur in any part of the body containing lymph nodes and is most common in the chest, followed by the neck, abdomen, and axillae. A 37-year-old woman was admitted to our hospital because of a tumor near the adrenal gland found by computed tomography. Positron emission tomography-computed tomography revealed that the retroperitoneal tumor may be a malignant disease. However, the pathological diagnosis after laparoscopic resection was retroperitoneal Castleman's disease, hyaline vascular type.

A Combination of circRNAs as a Diagnostic Tool for Discrimination of Papillary Thyroid Cancer.

BACKGROUND AND AIM: Circular RNAs (circRNAs) have been highlighted to exert essential biological functions in papillary thyroid cancer (PTC). The purpose of this study was explore diagnostic utility of circRNAs in PTC patients. PATIENTS AND METHODS: The distinctive expression profile of serum circRNAs was determined by individual quantitative real-time PCR (qRT-PCR) in two independent cohorts of 113 PTC patients, 80 thyroid nodules, and 111 healthy controls (HCs). A combination of circRNAs (circRNA-based combination index) was constructed by logistic regression. RESULTS: Individual qRT-PCR identification showed that two circRNAs (circRAPGEF5 and hsa_circ_0058124) were significantly up-regulated in PTC patients compared with HCs and thyroid nodules. Receiver-operating characteristic (ROC) curve analysis suggested that a combination of circRNAs was superior to individual circRNA in distinguishing PTC patients from HCs and thyroid nodules with area under ROC curve of more than 0.80. Furthermore, the combination of circRNAs increased significantly after systematic treatment, suggesting that it could monitor PTC dynamics. Additionally, the combination of circRNAs was independently correlated with PTC presence. CONCLUSION: The combination of these altered circRNAs was correlated with PTC and may serve as a novel diagnostic approach.

Morphological Disparity of the Mouthparts in Polyphagous Species of Largidae (Heteroptera: Pentatomomorpha: Pyrrhocoroidea) Reveals Feeding Specialization.

Mouthpart structures were observed in four species of Largidae using scanning electron microscopy to investigate their morphological disparity, and linked to changes in feeding specialization. The examined species are pests that feed mainly on seeds and plant sap of forbs, shrubs, and trees. Their external mouthparts are described in detail for the first time herein. The cone-like labrum and four-segmented tube-like labium are shorter in Physopelta species than in Macrocheraia grandis (Grey). The labium surface in all studied species bears nine types of sensilla (St1-St2, Sb1-3, Sch, Sca1-2, Sm). The distributions of sensilla on particular labial segments varies among the studied species. The tripartite apex of the labium consists of two lateral lobes and an apical plate that is partly divided in Physopelta species, and not divided in Macrocheraia. Each lateral lobe possesses a sensillar field with 10 thick-walled uniporous sensilla basiconica, one multiporous sensillum styloconicum, and one long non-porous hair sensillum. Each mandibular stylet tip in M. grandis has a central tooth placed anteriorly and pairs of teeth arranged dorso-laterally. In Physopelta, there are one or two central teeth placed anteriorly but two pairs of teeth dorso-laterally. In all studied species, the inner surfaces of the mandibular stylets have scale-like projections. A left-right asymmetry of the maxillary stylets is noticeable; the external end of the right maxillary stylet is smooth and slightly tapered in M. grandis and evidently wider (spoon-like) in the three species of Physopelta, while the left end of the stylets is straight and narrow in M. grandis in contrast to Physopelta, in which the end is straight and wide. No differences in the internal structure of the maxillary stylets were observed among the studied species. Based on structural differences, we inferred that the mandibles and maxillae are more adapted for seed-sucking in Physopelta species than in M. grandis. M. grandis has the ends of the maxillae more narrowed, a trait more adapted for sucking sap from phloem or parenchymal cells.

No more helper adenovirus: production of gutless adenovirus (GLAd) free of adenovirus and replication-competent adenovirus (RCA) contaminants.

Gene therapy is emerging as an effective treatment option for various inherited genetic diseases. Gutless adenovirus (GLAd), also known as helper-dependent adenovirus (HDAd), has many notable characteristics as a gene delivery vector for this particular type of gene therapy, including broad tropism, high infectivity, a large transgene cargo capacity, and an absence of integration into the host genome. Additionally, GLAd ensures long-term transgene expression in host organisms owing to its minimal immunogenicity, since it was constructed following the deletion of all the genes from an adenovirus. However, the clinical use of GLAd for the treatment of inherited genetic diseases has been hampered by unavoidable contamination of the highly immunogenic adenovirus used as a helper for GLAd production. Here, we report the production of GLAd in the absence of a helper adenovirus, which was achieved with a helper plasmid instead. Utilizing this helper plasmid, we successfully produced large quantities of recombinant GLAd. Importantly, our helper plasmid-based system exclusively produced recombinant GLAd with no generation of helper plasmid-originating adenovirus and replication-competent adenovirus (RCA). The recombinant GLAd that was produced efficiently delivered transgenes regardless of their size and exhibited therapeutic potential for Huntington's disease (HD) and Duchenne muscular dystrophy (DMD). Our data indicate that our helper plasmid-based GLAd production system could become a new platform for GLAd-based gene therapy.

Association of retinol binding protein-4, cystatin C, homocysteine and high-sensitivity C-reactive protein levels in patients with newly diagnosed type 2 diabetes mellitus.

INTRODUCTION: To investigate the serum retinol binding protein (RBP)-4, cystatin C (Cys C), homocysteine (HCY) and high-sensitivity C-reactive protein (hs-CRP) levels in newly diagnosed type 2 diabetes mellitus (NT2DM) patients, prediabetes mellitus (PDM) subjects and normal controls, as well as their correlation with clinical and laboratory indexes, such as blood pressure and lipoprotein. MATERIAL AND METHODS: A total of 242 subjects, including 141 NT2DM patients, 48 PDM subjects and 53 healthy controls, were recruited in the present study. Serum RBP-4, Cys C and hs-CRP concentrations were measured by enzyme-linked immunosorbent assay (ELISA). HCY concentration was determined by the chemical luminescence method. RESULTS: There were significant differences in Cys C and hs-CRP among NT2DM patients, PDM subjects and normal controls. In comparison to controls, there were significantly elevated Cys C and hs-CRP levels in PDM (both p < 0.001), and a significantly increased Cys C level in NT2DM (p < 0.001); however, there were no significant differences in Cys C and hs-CRP levels between NT2DM and PDM, and no significant differences of hs-CRP levels between NT2DM and normal controls. No significant differences of RBP-4 and HCY levels among NT2DM, PDM and normal control groups were observed. CONCLUSIONS: Aberrant Cys C expression and its clinical associations in NT2DM suggest their important role in this disease.

Breathing New Life into TRAIL for Breast Cancer Therapy: Co-Delivery of pTRAIL and Complementary siRNAs Using Lipopolymers.

Preclinical studies showed that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) therapy is safe and effective to combat cancers, but clinical outcomes have been less than optimal due to short half-life of TRAIL protein, insufficient induction of apoptosis, and TRAIL resistance displayed in many tumors. In this study, we explored co-delivery of a TRAIL expressing plasmid (pTRAIL) and complementary small interfering RNAs (siRNAs) (silencing Bcl2-like 12 [BCL2L12] and superoxide dismutase 1 [SOD1]) to improve the response of breast cancer cells against TRAIL therapy. It is desirable to co-deliver the pDNA along with siRNA using a single delivery agent, but this is challenging given different structures of long/flexible pDNA and short/rigid siRNA. Toward this goal, we identified an aliphatic lipid-grafted low-molecular weight polyethylenimine (PEI) that accommodated both pDNA and siRNA in a single complex. The co-delivery of pTRAIL with BCL2L12- or SOD1-specific siRNAs resulted more significant cell death in different breast cancer cells compared with separate delivery without affecting nonmalignant cells viability. Ternary complexes of lipopolymer with pTRAIL and BCL2L12 siRNA significantly retarded the growth of breast cancer xenografts in mice. The enhanced anticancer activity was attributed to increased in situ secretion of TRAIL and sensitization of breast cancer cells against TRAIL by the co-delivered siRNAs. The lipid-grafted PEIs capable of co-delivering multiple types of nucleic acids can serve as powerful carriers for more effective complementary therapeutics. Graphical Abstract [Figure: see text].

Silibinin ameliorates diabetic nephropathy via improving diabetic condition in the mice.

Diabetic nephropathy (DN) is a major cause of end-stage renal disease and one of the most severe diabetic complications. However, there is lack of effective treatments for DN and the underlying mechanisms of the renal injury remain unclear. In current study, we evaluated the effects of silibinin on DN and further explored the underlying mechanisms. We administrated silibinin to db/db mice for 10 weeks. Then we monitored the diabetic metabolic parameters, kidney function, oxidative stress and AKT signaling pathway in db/db mice. Administration of silibinin to db/db mice improved diabetic condition, as evidenced by the decrease of body weight, HbAc1level and serum insulin level in db/db mice. Silibinin prevented kidney injury and attenuated oxidative stress in db/db mice. Silibinin activated AKT signaling pathway and decreased the levels of p-GSK-3ß, Bax and cleaved caspase-3. Silibinin ameliorates diabetic nephropathy by activating the AKT signaling pathway.

Enhancement of TRAIL-induced apoptosis by 5-fluorouracil requires activating Bax and p53 pathways in TRAIL-resistant lung cancers.

Lung cancer, especially lung adenocarcinoma, is one of the main causes of death worldwide. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a primary anticancer agent and a member of the tumor necrosis factor family that selectively induces apoptosis in various tumor cells, but not in normal cells. Combination chemotherapy can be used for treating specific cancer types even at progressive stages. In the present study, we observed that 5-fluorouracil, which exerts anticancer effects by inhibiting tumor cell proliferation, enhanced TRAIL-induced apoptosis of TRAIL-resistant human adenocarcinoma A549 cells. Interestingly, 5-fluorouracil treatment markedly increased Bax and p53 levels and 5-fluorouracil and TRAIL cotreatment increased Ac-cas3 and Ac-cas8 levels compared with those in control cells. Taken together, the present study demonstrated that 5-fluorouracil enhances TRAIL-induced apoptosis in TRAIL-resistant lung adenocarcinoma cells by activating Bax and p53, and also suggest that TRAIL and 5-fluorouracil cotreatment can be used as an adequate therapeutic strategy for TRAIL-resistant human cancers.

Structure and Sensilla of the Mouthparts of the Spotted Lanternfly Lycorma delicatula (Hemiptera: Fulgoromorpha: Fulgoridae), a Polyphagous Invasive Planthopper.

Mouthparts are among the most important sensory and feeding structures in insects and comparative morphological study may help explain differences in feeding behavior and diet breadth among species. The spotted lanternfly Lycorma delicatula (White) (Hemiptera: Fulgoromorpha: Fulgoridae) is a polyphagous agricultural pest originating in China, recently established and becoming widespread in Korea, and more recently introduced into eastern North America. It causes severe economic damage by sucking phloem sap and the sugary excrement produced by nymphs and adults serves as a medium for sooty mold. To facilitate future study of feeding mechanisms in this insect, the fine-structural morphology of mouthparts focusing on the distribution of sensilla located on the labium in adult L. delicatula was observed using a scanning electron microscope. The mouthparts consist of a small cone-shaped labrum, a tubular labium and a stylet fascicle consisting of two inner interlocked maxillary stylets partially surrounded by two shorter mandibular stylets similar to those found in other hemipteran insects. The five-segmented labium is unusual (most other Fulgoromorpha have four segments) and is provided with several types of sensilla and cuticular processes situated on the apex of its distal labial segment. In general, nine types of sensilla were found on the mouthparts. Six types of sensilla and four types of cuticular processes are present on sensory fields of the labial apex. The proposed taxonomic and functional significance of the sensilla are discussed. Morphological similarities in the interlocking mechanism of the stylets suggest a relationship between Fulgoromorpha and Heteroptera.

Synthesis of La-Co-O Mixed Oxides via Polyethylene Glycol-Assisted Co-Precipitation Method for Total Oxidation of Benzene.

La-Co-O mixed oxides (LCO) were prepared by co-precipitation method with the presence of polyethylene glycol (PEG) as dispersant. The influence of adding different molecular weight of PEG (0, 2 000, 6 000, 20 000 g·mol-1) on the physicochemical and catalytic properties of La-Co-O mixed oxides for total oxidation of benzene was investigated. The samples were characterized by means of N2 physical adsorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature-programmed reduction by H2 (H2-TPR), temperature-programmed desorption of O2 (O2-TPD), and X-ray photoelectron spectroscopy (XPS). The order of catalytic activity was found to be LCO-PEG6000>LCO>LCO-PG20000>LCO-PG2000. Particularly, LCO-PEG6000 exhibited benzene conversion of 99% at temperature as low as 383 ℃, which was 126 ℃ lower than that of LCO. The characterization result reveals that all samples had a BET surface area of about 9～10 m2·g-1. The XRD result shows that on all samples LaCoO3 perovskite was mainly formed together with a small amount of La2O3 and Co3O4. The addition of PEG was favorable for the formation of LaCoO3 perovskite. Particularly, the addition of PEG-6000 effectively suppressed the agglomeration of LaCoO3 perovskite, giving rise to small and uniform particles as observed by SEM. Moreover, the results of H2-TPR and O2-TPD indicate that the obtained La-Co-O mixed oxides showed higher reducibility and lattice oxygen mobility, and the Co 2p XPS analysis suggests that more surface Co3+ active species were presented by the addition of PEG-6000. These properties are thought to contribute to the high activity in benzene total oxidation.

Brain microvascular endothelium induced-annexin A1 secretion contributes to small cell lung cancer brain metastasis.

Small cell lung cancer is the most aggressive histologic subtype of lung cancer, with a strong predilection for metastasizing to brain early. However, the cellular and molecular basis is poorly known. Here, we provided evidence to reveal the role of annexin A1 in small cell lung cancer metastasis to brain. Firstly, the elevated annexin A1 serum levels in small cell lung cancer patients were associated with brain metastasis. The levels of annexin A1 were also upregulated in NCI-H446 cells, a small cell lung cancer cell line, upon migration into the mice brain. More interestingly, annexin A1 was secreted by NCI-H446 cells in a time-dependent manner when co-culturing with human brain microvascular endothelial cells, which was identified with the detections of annexin A1 in the co-cultured cellular supernatants by ELISA and western blot. Further results showed that blockage of annexin A1 in the co-cultured cellular supernatants using a neutralized antibody significantly inhibited NCI-H446 cells adhesion to brain endothelium and its transendothelial migration. Conversely, the addition of Ac2-26, an annexin A1 mimic peptide, enhanced these effects. Furthermore, knockdown of annexin A1 in NCI-H446 cells prevented its transendothelial migration in vitro and metastasis to mice brain in vivo. Our data showed that small cell lung cancer cell in brain microvasculature microenvironment could express much more annexin A1 and release it outside, which facilitated small cell lung cancer cell to gain malignant properties of entry into brain. These findings provided a potential target for the management of SCLC brain metastasis.

Dual specific antitumor effects of Semliki Forest virus-based DNA vector carrying suicide Escherichia coli purine nucleoside phosphorylase gene via Salmonella.

The Escherichia coli purine nucleoside phospho-rylase/2-fluoro-2-deoxyadenosine (ePNP/F-dAdo) suicide system has demonstrated a powerful killing and bystander effects on tumor cells. However, several drawbacks to this approach remain to be resolved, such as the side-effects and the low efficiency of ePNP-targeted expression. A human telo-merase reverse transcriptase promoter-driven Semliki Forest virus-based DNA vector (pShT-ePNP) with high expression of the ePNP gene was constructed. Live attenuated Salmonella typhimurium 7207 (SL7207) was used initially as a vehicle to targetly transfer the large alphavirus vector into tumor cells. The in vitro quantitative analysis showed ~2-fold higher green fluorescent protein (GFP) expression for pShT-GFP than for conventional cytomegalovirus (CMV) promoter-mediated eukaryotic expression plasmids such as pIRES-GFP and the targeted expression of the ePNP gene in tumor cells was also detected by RT-PCR. After F-dAdo addition, the enzymatic conversion of F-Ado into 2-fluoroadmine (F-Ade) was tested by HPLC. Cell cytotoxicity assays showed that the significant inhibitory effect of the SL/pShT-ePNP system on tumor cells was dose- and time-dependent. Following oral administration, recombinant bacteria targetly allocated within the solid tumor and the expression of ePNP and GFP genes in vivo were detected by RT-PCR or observed by fluorescence microscopy. SL/pShT-ePNP and F-dAdo were also found to exert powerful therapeutic effects in combination against tumor growth and for prolonging the lifespan of tumor-bearing mice. These findings suggest that the SL/pShT-ePNP system may serve as a powerful strategy for tumor therapy.

DUSP6 is a novel transcriptional target of p53 and regulates p53-mediated apoptosis by modulating expression levels of Bcl-2 family proteins.

p53 regulates various cellular responses through transcriptional regulation of distinct sets of target genes. Dual specificity phosphatase 6 (DUSP6) is a cytosolic phosphatase that inactivates the extracellular-signal-regulated kinase 1/2 (ERK1/2). This study demonstrates that p53 transactivates DUSP6 in human colorectal HCT116 cells to regulate ERK1/2 in p53-mediated cell death. DUSP6 is transactivated by p53 overexpression and genotoxic agents, and chromatin immunoprecipitation revealed two p53-binding sites in the DUSP6 promoter responsible for DUSP6 induction. Expression of shDUSP6 inhibited 5'-FU-induced cell death, whereas overexpression of DUSP6 increased susceptibility to 5'-FU. 5'-FU treatment dephosphorylated ERK in a DUSP6-dependent manner, resulting in destabilization of Bcl-2 and stabilization of Bad. These results provide insights on the modulatory role of p53 in the survival pathway by up-regulating DUSP6.

Ampelopsin inhibits H2O2-induced apoptosis by ERK and Akt signaling pathways and up-regulation of heme oxygenase-1.

Oxidative stress plays an important role in neurodegenerative disorders. Ampelopsin, a flavonoid abundant in Rattan tea (Ampelopsis grossedentata), is a potent antioxidant and its neuroprotective effect against H2O2-induced apoptosis in PC12 cells is investigated here for the first time. It was found that treatment of cells with ampelopsin for 1 h significantly reduced the loss of vitality, LDH release and apoptosis and inhibited the formation of reactive oxygen species (ROS). Ampelopsin was able to prevent the activation of p38 induced by H2O2. In addition, up-regulation of heme oxygenase-1 (HO-1) expression by ampelopsin was shown to be both dose- and time-dependent. Mechanically, HO-1 expression induced by ampelopsin was found to be due to activation of the ERK and Akt signaling pathways, because it was almost completely blocked by the specific inhibitors of ERK and Akt. These results suggest that ampelopsin increases cellular antioxidant defense through activation of the ERK and Akt signaling pathways, which induces HO-1 expression and thereby protects PC12 cells from H2O2-induced apoptosis.

p53-Independent up-regulation of a TRAIL receptor DR5 by proteasome inhibitors: a mechanism for proteasome inhibitor-enhanced TRAIL-induced apoptosis.

Gliomas are the most common brain tumors in adults and account for more than half of all brain tumors. Despite intensive clinical investigations, average survival for the patients harboring the malignancy has not been significantly improved. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), shown to have potent and cancer-selective killing activity, has drawn considerable attention as a promising anti-cancer therapy. In an attempt to develop TRAIL as an anti-cancer therapy for gliomas, tumor suppressor activity of TRAIL was assessed using human glioma cell lines such as U373MG, U343MG, U87MG and LN18. U343MG, U87MG and LN18 cells were susceptible to TRAIL; however, U373MG cells were completely refractory to TRAIL. Resistance to the applied therapies is a key issue in cancer treatment; thus, various combination treatments were evaluated using U373MG cells to identify a better regimen. Unlike Doxorubicin, Etoposide, Actinomycin D and Wortmannin, a proteasome inhibitor MG132 significantly enhanced TRAIL-induced apoptosis. Similarly, other proteasome inhibitors, including Lactacystin, Proteasome inhibitor I and Velcade (Bortezomib), also enhanced apoptotic activity of TRAIL. Among these proteasome inhibitors, Velcade, the only approved drug, was as effective as MG132 in enhancing TRAIL-induced apoptosis. Both Velcade and MG132 increased the protein levels of DR5, a TRAIL receptor known to be up-regulated by p53, in U373MG cells where p53 is mutated. Our data indicate that proteasome inhibitors up-regulate DR5 in a p53-independent manner and a combination therapy comprising TRAIL and Velcade become a better treatment regimen for gliomas.