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Since the discovery of RNA interference (RNAi), RNAi technology has rapidly developed into an efficient tool for post-transcriptional gene silencing, which has been widely used for clinical or preclinical treatment of various diseases including cancer. Small interfering RNA (siRNA) is the effector molecule of RNAi technology. However, as polyanionic macromolecules, naked siRNAs have a short circulatory half-life (

The expression of Proline-, glutamic acid-, and leucine-rich protein 1 (PELP1) has been reported to be dysregulated in non-small cell lung carcinoma, especially in lung adenocarcinoma (LUAD). Therefore, we aimed to investigate the functional and prognostic roles of PELP1 in LUAD in this study. We first immunolocalized PELP1 in 76 cases of LUAD and 17 non-pathological or tumorous lung (NTL) tissue specimens and correlated the findings with the clinicopathological parameters of the patients. We then performed in vitro analysis including MTT, flow cytometry, wound healing, and transwell assays in order to further explore the biological roles of PELP1 in 17-β-estradiol (E2) induced cell proliferation, migration, and invasion of LUAD cells. We subsequently evaluated the prognostic significance of PELP1 in LUAD patients using the online survival analysis tool Kaplan-Meier Plotter. The status of PELP1 immunoreactivity in LUAD was significantly higher than that in the NTL tissues and significantly positively correlated with less differentiated features of carcinoma cells, positive lymph node metastasis, higher clinical stage as well as the status of ERα, ERβ, and PCNA. In vitro study did reveal that E2 promoted cell proliferation and migration and elevated PELP1 protein level in PELP1-high A549 and H1975 cells but not in PELP1-low H-1299 cells. Knock down of PELP1 significantly attenuated E2 induced cell proliferation, colony formation, cell cycle progress as well as migration and invasion of A549 and H1975 cells. Kaplan-Meier Plotter revealed that LUAD cases harboring higher PELP1 expression had significantly shorter overall survival. In summary, PELP1 played a pivotal role in the estrogen-induced aggressive transformation of LUAD and could represent adverse clinical outcome of the LUAD patients.

Macrophages are mainly divided into two phenotypes: M1-like (anti-tumoral, pro-inflammatory) and M2-like (pro-tumoral, anti-inflammatory). The more abundant M2-like phenotype of tumor associated macrophages (TAMs) has been associated with poor prognosis in various cancers, therefore, many studies have been carried out to modulate TAMs to change from an M2 to M1-like phenotype as an effective way to suppress tumor growth. Previous study indicated that the FDA-approved Ferumoxytol is an iron oxide nanoparticle that has intrinsic tumor inhibiting properties and is accompanied by the increased presence of the pro-inflammatory, anti-tumoral M1-like phenotype. Intrigued by this finding, we hypothesize that differently charged super-paramagnetic iron oxide nanoparticles (SPIONs) would have preferential differences in polarizing macrophages. Herein, we report that differently charged SPIONs have distinct preferences in the modulation of TAM phenotypes. Positively charged SPION (S+) had the highest cellular uptake and highest macrophage polarization effect. Interestingly, although negatively charged SPION (S−) should present charge–charge repulsion with cell membranes, they showed considerably high uptake in vitro, nevertheless presenting the highest cellular toxicity. Neutrally charged SPION (SN) showed minimal uptake and cellular toxicity in vitro. Both S+ and S− could effectively re-polarize M2-like macrophages toward M1-like macrophages in vitro, and significantly increased the Fenton effect and chemotaxis of macrophages. When macrophages pre-treated with these SPIONs were co-injected with tumor cells to obtain a tumor xenograft, S+ and S− treated macrophages significantly induced tumor retardation, indicating the successful repolarization of tumor macrophages by these SPIONs. Taken together, we provide an insight on the importance of SPION charge in immunomodulation of macrophages.

Pancreatic cancer (PAC) is one of the most lethal malignant neoplasms with poor prognosis and high mortality. Emerging evidence has revealed that abnormal tumor lipid metabolism and tumor-associated macrophages (TAMs) significantly contribute to PAC development and progression. Therefore, concurrently reprogramming tumor lipid metabolism and regulating TAMs function could be a promising strategy for effective PAC therapy. Herein, we identified an important enzyme catabolizing lipids (monoacylglycerol lipase, MGLL) and a key receptor regulating macrophage phenotype (endocannabinoid receptor-2, CB-2) that are over-expressed in PAC cells and on TAMs, respectively. Based on this finding, we developed a reduction-responsive poly (disulfide amide) (PDSA)-based nanoplatform for systemic co-delivery of MGLL siRNA (siMGLL) and CB-2 siRNA (siCB-2). This nanoplatform could utilize its reduction-responsive characteristic to rapidly release siRNA for efficient silencing of MGLL and CB-2, inducing concurrent suppression of free fatty acids (FFAs) generation in PAC cells and repolarization of TAMs into tumor-inhibiting M1-like phenotype. With this suppressed FFAs generation to inhibit nutrient supply for tumor cells and repolarized TAMs to secrete tumoricidal cytokines such as TNF-α and IL-12, a combinational anticancer effect could be achieved in both xenograft and orthotopic PAC tumor models.

Background Compounds with the ability to scavenge reactive oxygen species (ROS) and inhibit tyrosinase may be useful for the treatment and prevention from ROS-related diseases. The number and location of phenolic hydroxyl of the flavonoids will significantly influence the inhibition of tyrosinase activity. Phenolic hydroxyl is indispensable to the antioxidant activity of flavonoids. Isoeugenol, shikonin, baicalein, rosmarinic acid, and dihydromyricetin have respectively one, two, three, four, or five phenolic hydroxyls. The different molecular structures with the similar structure to l-3,4-dihydroxyphenylalanine (l-DOPA) were expected to the different antityrosinase and antioxidant activities. Methods This investigation tested the antityrosinase activity, the inhibition constant, and inhibition type of isoeugenol, shikonin, baicalein, rosmarinic acid, and dihydromyricetin. Molecular docking was examined by the Discovery Studio 2.5 (CDOCKER Dock, Dassault Systemes BIOVIA, USA). This experiment also examined the antioxidant effects of the five compounds on supercoiled pBR322 plasmid DNA, lipid peroxidation in rat liver mitochondria in vitro, and DPPH, ABTS, hydroxyl, or superoxide free radical scavenging activity in vitro. Results The compounds exhibited good antityrosinase activities. Molecular docking results implied that the compounds could interact with the amino acid residues in the active site center of antityrosinase. These compounds also exhibited antioxidant effects on DPPH, ABTS, hydroxyl, or superoxide free radical scavenging activity in vitro, lipid peroxidation in rat liver mitochondria induced by Fe2+/vitamin C system in vitro, and supercoiled pBR322 plasmid DNA. The activity order is isoeugenol

Three phloretin derivates were achieved through condensation of the phloretin template with thiosemicarbazide, 4-methylthiosemicarbazide, and 4-phenyl-3-thiosemicarbazide. Their purity was confirmed by high-performance liquid chromatograph and their structures were determined from their ultraviolet spectra, Fourier-transform infrared, 1H and 13C NMR, and mass spectra. The solubility of these novel compounds in ultrapure water at 25 °C was significantly improved compared with that of phloretin in the following order: phloretin thiosemicarbazone (PT, >1.00 mg/mL) > phloretin-4-phenyl-3-thiosemicarbazone (PPT, 0.52 mg/mL) > phloretin-4-methylthiosemicarbazone (PMT, 0.24 mg/mL) > phloretin (0.02 mg/mL). The tyrosinase inhibitory effect and various antioxidant assays in vitro were evaluated. Results showed that PT possesses potent tyrosinase inhibitory activity (IC50 = 57.81 ± 1.46 μM), which was better than phloretin (IC50 = 70.08 ± 0.88 μM). They also significantly quenched 1,1-diphenyl-2-picryl-hydrazyl and exhibited strong activity against the lipid peroxidation induced by Fe2+/ascorbic acid. Likewise, these compounds significantly protected against 2,2′-azo-bis(2-amidinopropane)dihydrochloride-induced Cu, Zn-superoxide dismutase, and pBR322 plasmid DNA damage in a dose-dependent manner.

There is a clinical need for new, more effective treatments for chronic wounds in diabetic patients. Lack of epithelial cell migration is a hallmark of nonhealing wounds, and diabetes often involves endothelial dysfunction. Therefore, targeting re-epithelialization, which mainly involves keratinocytes, may improve therapeutic outcomes of current treatments. In this study, we present an integrin-binding prosurvival peptide derived from angiopoietin-1, QHREDGS (glutamine-histidine-arginine-glutamic acid-aspartic acid-glycine-serine), as a therapeutic candidate for diabetic wound treatments by demonstrating its efficacy in promoting the attachment, survival, and collective migration of human primary keratinocytes and the activation of protein kinase B Akt and MAPKp42/44. The QHREDGS peptide, both as a soluble supplement and when immobilized in a substrate, protected keratinocytes against hydrogen peroxide stress in a dose-dependent manner. Collective migration of both normal and diabetic human keratinocytes was promoted on chitosan–collagen films with the immobilized QHREDGS peptide. The clinical relevance was demonstrated further by assessing the chitosan–collagen hydrogel with immobilized QHREDGS in full-thickness excisional wounds in a db/db diabetic mouse model; QHREDGS showed significantly accelerated and enhanced wound closure compared with a clinically approved collagen wound dressing, peptide-free hydrogel, or blank wound controls. The accelerated wound closure resulted primarily from faster re-epithelialization and increased formation of granulation tissue. There were no observable differences in blood vessel density or size within the wound; however, the total number of blood vessels was greater in the peptide-hydrogel–treated wounds. Together, these findings indicate that QHREDGS is a promising candidate for wound-healing interventions that enhance re-epithelialization and the formation of granulation tissue.

Background Triple-negative breast cancer (TNBC) is associated with an aggressive clinical course due to the lack of therapeutic targets. Therefore, identifying reliable prognostic biomarkers and novel therapeutic targets for patients with TNBC is required. Proline, glutamic acid, leucine rich protein 1 (PELP1) is a novel steroidal receptor co-regulator, functioning as an oncogene and its expression is maintained in estrogen receptor (ER) negative breast cancers. PELP1 has been proposed as a prognostic biomarker in hormone-related cancers, including luminal-type breast cancers, but its significance in TNBC has not been studied. Methods PELP1 immunoreactivity was evaluated using immunohistochemistry in 129 patients with TNBC. Results were correlated with clinicopathological variables including patient’s age, tumor size, lymph node stage, tumor grade, clinical stage, histological type, Ki-67 LI, as well as clinical outcome of the patients, including disease-free survival (DFS) and overall survival (OS). Results PELP1 was localized predominantly in the nuclei of carcinoma cells in TNBC. With the exception of a positive correlation between PELP1 protein expression and lymph node stage (p = 0.027), no significant associations between PELP1 protein expression and other clinicopathological variables, including DFS and OS, were found. However, when PELP1 and Ki-67 LI were grouped together, we found that patients in the PELP1/Ki-67 double high group (n = 48) demonstrated significantly reduced DFS (p = 0.005, log rank test) and OS (p = 0.002, log rank test) than others (n = 81). Multivariable analysis supported PELP1/Ki-67 double high expression as an independent prognostic factor in patients with TNBC, with an adjusted hazard ratio of 2.020 for recurrence (95 % CL, 1.022–3.990; p = 0.043) and of 2.380 for death (95 % CL, 1.138–4.978; p = 0.021). Conclusions We found that evaluating both PELP1 and Ki-67 expression in TNBC could enhance the prognostic sensitivity of the two biomarkers. Therefore, we propose that PELP1/Ki-67 double high expression in tumors is an independent prognostic factor for predicting a poor outcome for patients with TNBC.

In this paper, the antioxidative and anticancer activities of tea glycoprotein (TGP) in green tea were studied. TGP was extracted from coarse old green tea and purified by Sephadex G-100 gel filtration, and its purity was determined by high performance gel permeation chromatography (HPGPC). The antioxidative activity of the TGP was evaluated by determining the change of the values of the heat-induced oxidation in a linoleic acid system with β-carotene, the decoloration of the 1,1-diphenyl-2-picrylhydrazyl (DPPH), and the superoxide generated from autoxidation of pyrogallol. The results show that the TGP possesses distinctive antioxidative activity. Furthermore, the anticancer activity of the TGP at different concentrations was evaluated by the MTT assay using two kinds of colon cancer cell lines (HCT-15, Caco-2). Dose-dependently TGP exhibited good antiproliferation activity to HCT-15, whereas exhibited very weak antiproliferation activity to Caco-2. Only at a very high concentration (409.6 μmol L−1), the TGP obviously inhibited the proliferation of Caco-2. Whether there is a correlation between the antioxidative and the anticancer activity of the TGP, should be studied further.

Microglial activation and adaptive immunity have been implicated in the neurodegenerative processes in Parkinson disease. It has been proposed that these responses may be triggered by modified forms of alpha-synuclein (alpha-SYN), particularly nitrated species, which are released as a consequence of dopaminergic neurodegeneration. To examine the relationship between alpha-SYN, microglial activation, and adaptive immunity, we used a mouse model of Parkinson disease in which human alpha-SYN is overexpressed by a recombinant adeno-associated virus vector, serotype 2 (AAV2-SYN); this overexpression leads to slow degeneration of dopaminergic neurons. Microglial activation and components of the adaptive immune response were assessed using immunohistochemistry; quantitative polymerase chain reaction was used to examine cytokine expression. Four weeks after injection, there was a marked increase in CD68-positive microglia and greater infiltration of B and T lymphocytes in the substantia nigra pars compacta of the AAV2-SYN group than in controls. At 12 weeks, CD68 staining declined, but B- and T-cell infiltration persisted. Expression of proinflammatory cytokines was enhanced, whereas markers of alternative activation (i.e. arginase I and interleukins 4 and 13) were not altered. Increased immunoreactivity for mouse immunoglobulin was detected at all time points in the AAV2-SYN animals. These data show that overexpression of alpha-SYN alone, in the absence of overt neurodegeneration, is sufficient to trigger neuroinflammation with both microglial activation and stimulation of adaptive immunity.

Background The protein alpha-synuclein (α-SYN), which is found in the Lewy bodies of dopamine-producing (DA) neurons in the substantia nigra (SN), has an important role in the pathogenesis of Parkinson’s disease (PD). Previous studies have shown that neuroinflammation plays a key role in PD pathogenesis. In an AAV-synuclein mouse model of PD, we have found that over-abundance of α-SYN triggers the expression of NF-κB p65, and leads to microglial activation and DA neurodegeneration. We also have observed that Fcγ receptors (FcγR), proteins present on the surface of microglia that bind immunoglobulin G (IgG) and other ligands, are key modulators of α-SYN-induced neurodegeneration. Methods In order to study the role of FcγRs in the interactions of α-SYN and microglia, we treated the primary microglial cultures from wild-type (WT) and FcγR−/− mice with aggregated human α-SYN in vitro. Results Using immunocytochemistry, we found that α-SYN was taken up by both WT and FcγR−/− microglia, however, their patterns of internalization were different, with aggregation in autophagosomes in WT cells and more diffuse localization in FcγR−/− microglia. In WT microglia, α-SYN induced the nuclear accumulation of NF-κB p65 protein and downstream chemokine expression while in FcγR−/− mouse microglia, α-SYN failed to trigger the enhancement of nuclear NF-κB p65, and the pro-inflammatory signaling was reduced. Conclusions Our results suggest that α-SYN can interact directly with microglia and can be internalized and trafficked to autophagosomes. FcγRs mediate this interaction, and in the absence of the gamma chain, there is altered intracellular trafficking and attenuation of pro-inflammatory NF-κB signaling. Therefore, blocking either FcγR signaling or downstream NF-κB activation may be viable therapeutic strategies in PD.

Background: Extraction temperature influences the total phenolic content (TPC), total flavonoid content (TFC) of medicinal plant extracts to a great extend. TPC and TFC are the principle activity constituents present in the plant. The effects of extraction temperature on TPC, TFC and free radical-scavenging capacity of Gynura divaricata leaf extracts are worth to study. Materials and Methods: Folin–Ciocalteu and aluminum chloride colorimetric assay were used to determine the TPC and TFC of Gynura divaricata leaf extracts at different temperatures. The antioxidant and free radical-scavenging activity were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and phosphomolybdenum methods. Results: TPC and TFC were significantly elevated with increasing extraction temperature (from 40°C to 100°C). However, TPC and TFC were not significantly different (P > 0.05) at the extraction temperatures 90°C and 100°C. Also, the extracts obtained at a higher temperature exhibited a significant free radical-scavenging activity compared with extraction at lower temperatures (P < 0.05). The TPCs (13.95-36.68 mg gallic acid equivalent/g dry material) were highly correlated with DPPH (R2 = 0.9229), ABTS (R2 = 0.9951) free radical-scavenging capacity, and total antioxidant activity (R2 = 0.9872) evaluated by phosphomolybdenum method. Conclusion: The TPC and TFC of G. divaricata leaf was significantly influenced by the extraction temperatures, which were the main antioxidant constituents present in the G. divaricata plant.

Overexpression of alpha-synuclein (α-SYN), a protein which plays an important role in the pathogenesis of Parkinson's disease (PD), triggers microglial activation and adaptive immune responses, and leads to neurodegeneration of dopaminergic (DA) neurons. We hypothesized a link between the humoral adaptive immune response and microglial activation in α-SYN induced neurodegeneration. To test this hypothesis, we employed adeno-associated virus serotype 2 (AAV2) to selectively over-express human α-SYN in the substantia nigra (SN) of wild-type mice and FcγR-/- mice, which lack high-affinity receptors for IgG. We found that in wild-type mice, α-SYN induced the expression of NF-κB p65 and pro-inflammatory molecules. In FcγR-/- mice, NF-κB activation was blocked and pro-inflammatory signaling was reduced. Microglial activation was examined using immunohistochemistry for gp91PHOX. At four weeks, microglia were strongly activated in wild-type mice, while microglial activation was attenuated in FcγR-/- mice. Dopaminergic neurodegeneration was examined using immunohistochemistry for tyrosine hydroxylase (TH) and unbiased stereology. α-SYN overexpression led to the appearance of dysmorphic neurites, and a loss of DA neurons in the SN in wild-type animals, while FcγR-/- mice did not exhibit neuritic change and were protected from α-SYN-induced neurodegeneration 24 weeks after injection. Our results suggest that the humoral adaptive immune response triggered by excess α-SYN plays a causative role in microglial activation through IgG-FcγR interaction. This involves NF-κB signaling, and leads to DA neurodegeneration. Therefore, blocking either FcγR signaling or specific intracellular signal transduction events downstream of FcγR-IgG interaction, such as NF-κB activation, may be viable therapeutic strategies in PD.