Structural insights into the unusual core photocomplex from a triply extremophilic purple bacterium, Halorhodospira halochloris.

Halorhodospira (Hlr.) halochloris is a triply extremophilic phototrophic purple sulfur bacterium, as it is thermophilic, alkaliphilic, and extremely halophilic. The light-harvesting-reaction center (LH1-RC) core complex of this bacterium displays an LH1-Qy transition at 1,016 nm, which is the lowest-energy wavelength absorption among all known phototrophs. Here we report the cryo-EM structure of the LH1-RC at 2.42 Å resolution. The LH1 complex forms a tricyclic ring structure composed of 16 αßγ-polypeptides and one αß-heterodimer around the RC. From the cryo-EM density map, two previously unrecognized integral membrane proteins, referred to as protein G and protein Q, were identified. Both of these proteins are single transmembrane-spanning helices located between the LH1 ring and the RC L-subunit and are absent from the LH1-RC complexes of all other purple bacteria of which the structures have been determined so far. Besides bacteriochlorophyll b molecules (B1020) located on the periplasmic side of the Hlr. halochloris membrane, there are also two arrays of bacteriochlorophyll b molecules (B800 and B820) located on the cytoplasmic side. Only a single copy of a carotenoid (lycopene) was resolved in the Hlr. halochloris LH1-α3ß3 and this was positioned within the complex. The potential quinone channel should be the space between the LH1-α3ß3 that accommodates the single lycopene but does not contain a γ-polypeptide, B800 and B820. Our results provide a structural explanation for the unusual Qy red shift and carotenoid absorption in the Hlr. halochloris spectrum and reveal new insights into photosynthetic mechanisms employed by a species that thrives under the harshest conditions of any phototrophic microorganism known.

Molecularly engineered dual-network photothermal hydrogel delivery system with enhanced mechanical properties, antibacterial ability and angiogenic effect for accelerating wound healing.

Bacterial infection caused by trauma and chronic wounds in the most mobile area remains a challenge in clinic. It is difficult to achieve the synergistic effects of antibacterial capacity and skin regeneration using conventional therapeutic methods. Developing a multi-functional hydrogel dressing that can cope with the complex wound environment will contribute to the healing and therapeutic effects. In this work, a novel Cur@PAM/TA-Cu photothermal hydrogel delivery system was prepared by engineering tannic acid (TA) into covalent cross-linked polyacrylamide (PAM) on which the chelating tannic acid-copper metal-polyphenolic network (TA-Cu MPN) was imposed to form dual-crosslinked networks, and the natural medicine curcumin was loaded eventually. The molecularly engineered dual-crosslinked networks resulted in enhanced mechanical properties including bio-adhesion, tensile strength and self-healing, which made the hydrogel suitable for dynamic wound and various application scenarios. In addition, the excellent photothermal capacity, antioxidant effect and biocompatibility of the hydrogel were demonstrated. Notably, this curcumin loaded photothermal hydrogel exhibited superior antibacterial capacity (almost 100% killing ratio to E. coli and S. aureus) under 808 nm laser irradiation. Meanwhile, the in vivo wound healing experiment results revealed that the anti-inflammation and proangiogenic effect of Cur@PAM/TA-Cu hydrogel successfully shortened the healing time of wound and the reconstruction of skin structure and function. Thus, this dual-crosslinked multi-functional hydrogel delivery system is a promising wound dressing for accelerating wound healing.

New insights on the photocomplex of Roseiflexus castenholzii revealed from comparisons of native and carotenoid-depleted complexes.

In wild-type phototrophic organisms, carotenoids (Crts) are primarily packed into specific pigment-protein complexes along with (Bacterio)chlorophylls and play important roles in the photosynthesis. Diphenylamine (DPA) inhibits carotenogenesis but not phototrophic growth of anoxygenic phototrophs and eliminates virtually all Crts from photocomplexes. To investigate the effect of Crts on assembly of the reaction center-light-harvesting (RC-LH) complex from the filamentous anoxygenic phototroph Roseiflexus (Rfl.) castenholzii, we generated carotenoidless (Crt-less) RC-LH complexes by growing cells in the presence of DPA. Here, we present cryo-EM structures of the Rfl. castenholzii native and Crt-less RC-LH complexes with resolutions of 2.86 Å and 2.85 Å, respectively. From the high-quality map obtained, several important but previously unresolved details in the Rfl. castenholzii RC-LH structure were determined unambiguously including the assignment and likely function of three small polypeptides, and the content and spatial arrangement of Crts with bacteriochlorophyll molecules. The overall structures of Crt-containing and Crt-less complexes are similar. However, structural comparisons showed that only five Crts remain in complexes from DPA-treated cells and that the subunit X (TMx) flanked on the N-terminal helix of the Cyt-subunit is missing. Based on these results, the function of Crts in the assembly of the Rfl. castenholzii RC-LH complex and the molecular mechanism of quinone exchange is discussed. These structural details provide a fresh look at the photosynthetic apparatus of an evolutionary ancient phototroph as well as new insights into the importance of Crts for proper assembly and functioning of the RC-LH complex.

Solid-in-oil nanodispersion as a novel topical transdermal delivery to enhance stability and skin permeation and retention of hydrophilic drugs l-ascorbic acid.

l-ascorbic acid （Vitamin C, VC） is the most abundant antioxidant in human skin. But its poor penetration into the skin and unstability limit the application. The aim of the study was to promote the topical skin permeation and retention of VC, increase the stability as well as effectiveness by a novel solid in oil nanodispersion. In the nanodispersions system, nano-sized particles of hydrophilic molecules are dispersed in an oil vehicle with the assistance of hydrophobic surfactants. The optimized formula composed of O170 and S1570 (12.5:1, w/w) showed high EE% of 98% and good stability. FTIR analysis confirmed that there may be hydrogen bond between VC and surfactants. The results of DSC, and XRD revealed that the drug was successfully encapsulated in the surfactants, which maintained the stability of drug. By analyzing and fitting the release data in vitro, the drug release mechanism of SONDs was predicted as a multi-dynamic model. Skin permeation of VC was improved 3.43-fold for SONDs compared with VC aqueous solution, highlighting that the lipophilicity and nano size of the carrier more easily penetrated into the skin. Finally, the photoaging study revealed that topical application of VC-SONDs provided the highest skin protection compared UV and VC aqueous solution treated group which was evident by the normal thick epidermal morphology, no obvious melanocytes and the densely arranged dermal elastic fibers. These results demonstrated that the solid-in-oil nanodispersions may be a potential transdermal delivery system for hydrophilic bioactive ingredients.

SATB2, coordinated with CUX1, regulates IL-1ß-induced senescence-like phenotype in endothelial cells by fine-tuning the atherosclerosis-associated p16INK4a expression.

Genome-wide association studies (GWAS) have validated a strong association of atherosclerosis with the CDKN2A/B locus, a locus harboring three tumor suppressor genes: p14ARF , p15INK4b , and p16INK4a . Post-GWAS functional analysis reveals that CUX is a transcriptional activator of p16INK4a via its specific binding to a functional SNP (fSNP) rs1537371 on the atherosclerosis-associated CDKN2A/B locus, regulating endothelial senescence. In this work, we characterize SATB2, another transcription factor that specifically binds to rs1537371. We demonstrate that even though both CUX1 and SATB2 are the homeodomain transcription factors, unlike CUX1, SATB2 is a transcriptional suppressor of p16INK4a and overexpression of SATB2 competes with CUX1 for its binding to rs1537371, which inhibits p16INK4a and p16INK4a -dependent cellular senescence in human endothelial cells (ECs). Surprisingly, we discovered that SATB2 expression is transcriptionally repressed by CUX1. Therefore, upregulation of CUX1 inhibits SATB2 expression, which enhances the binding of CUX1 to rs1537371 and subsequently fine-tunes p16INK4a expression. Remarkably, we also demonstrate that IL-1ß, a senescence-associated secretory phenotype (SASP) gene itself and a biomarker for atherosclerosis, induces cellular senescence also by upregulating CUX1 and/or downregulating SATB2 in human ECs. A model is proposed to reconcile our findings showing how both primary and secondary senescence are activated via the atherosclerosis-associated p16INK4a expression.

Efficacy and safety of direct oral anticoagulants for the treatment of cancer-associated venous thromboembolism: A systematic review and Bayesian network meta-analysis.

INTRODUCTION: Direct oral anticoagulants (DOACs) could effectively prevent the occurrence of cancer-associated venous thromboembolism (CAVTE), which incidence rate was estimated to be 4-20%. But the efficacy and safety remain controversial between DOACs and low molecular weight heparin (LMWH). MATERIALS AND METHODS: PubMed, Cochrane Library, Embase, ClinicalTrials.gov databases for randomized controlled trials (RCTs) were systematically searched from inception to March 15, 2022. A random-effects model was used to report the odds ratio (OR) and 95% confidence interval (CI) for both direct and network meta-analyses. RESULTS: Seven studies were included totaling 3242 patients. A lower rate of recurrence VTE was noted in the DOACs compared with LMWH (OR 0.62, 95% CI 0.47-0.82, I2=0.0%). The aspect of major bleeding (MB) was similar (OR 1.30, 95% CI 0.77-2.18, I2=34.9%). When assessing clinically relevant nonmajor bleeding (CRNMB) (OR 1.61, 95% CI 1.17-2.22, I2=20.7%) and clinically relevant bleeding (CRB) (OR 1.39, 95% CI 1.11-1.74, I2=0.0%), a higher risk of events was observed in DOACs. In subgroup analyses, the MB of gastrointestinal and genitourinary malignancies had a higher rate in the DOACs. For ranking, apixaban ranked the first in prevention of VTE and reducing MB events. Edoxaban had the highest risk drug in MB. In terms of CRNMB and CRB, LMWH showed the lowest risk. CONCLUSIONS: Compared with LMWH, DOACs seemed to have a decreased risk of recurrence VTE while increasing CRNMB and CRB. DOACs and LMWH were equivalent to the aspect of MB, but DOACs had a higher MB risk in patients with gastrointestinal and genitourinary malignancies. Apixaban may be the lowest risk compared to the other DOACs in precaution of VTE and reducing bleeding events.

Multifunctional Protein Hybrid Nanoplatform for Synergetic Photodynamic-Chemotherapy of Malignant Carcinoma by Homologous Targeting Combined with Oxygen Transport.

Photodynamic therapy (PDT) under hypoxic conditions and drug resistance in chemotherapy are perplexing problems in anti-tumor treatment. In addition, central nervous system neoplasm-targeted nanoplatforms are urgently required. To address these issues, a new multi-functional protein hybrid nanoplatform is designed, consisting of transferrin (TFR) as the multicategory solid tumor recognizer and hemoglobin for oxygen supply (ODP-TH). This protein hybrid framework encapsulates the photosensitizer protoporphyrin IX (PpIX) and chemotherapeutic agent doxorubicin (Dox), which are attached by a glutathione-responsive disulfide bond. Mechanistically, ODP-TH crosses the blood-brain barrier (BBB) and specifically aggregated in hypoxic tumors via protein homology recognition. Oxygen and encapsulated drugs ultimately promote a therapeutic effect by down-regulating the abundance of multidrug resistance gene 1 (MDR1) and hypoxia-inducible factor-1-α (HIF-1α). The results reveal that ODP-TH achieves oxygen transport and protein homology recognition in the hypoxic tumor occupation. Indeed, compared with traditional photodynamic chemotherapy, ODP-TH achieves a more efficient tumor-inhibiting effect. This study not only overcomes the hypoxia-related inhibition in combination therapy by targeted oxygen transport but also achieves an effective treatment of multiple tumors, such as breast cancer and glioma, providing a new concept for the construction of a promising multi-functional targeted and intensive anti-tumor nanoplatform.

A potent tumor-selective ERK pathway inactivator with high therapeutic index.

FDA-approved BRAF and MEK small molecule inhibitors have demonstrated some level of efficacy in patients with metastatic melanomas. However, these "targeted" therapeutics have a very low therapeutic index, since these agents affect normal cells, causing undesirable, even fatal, side effects. To address these significant drawbacks, here, we have reengineered the anthrax toxin-based protein delivery system to develop a potent, tumor-selective MEK inactivator. This toxin-based MEK inactivator exhibits potent activity against a wide range of solid tumors, with the highest activity seen when directed toward tumors containing the BRAFV600E mutation. We demonstrate that this reengineered MEK inactivator also exhibits an extremely high therapeutic index (>15), due to its in vitro and in vivo activity being strictly dependent on the expression of multiple tumor-associated factors including tumor-associated proteases matrix metalloproteinase, urokinase plasminogen activator, and anthrax toxin receptor capillary morphogenesis protein-2. Furthermore, we have improved the specificity of this MEK inactivator, restricting its enzymatic activity to only target the ERK pathway, thereby greatly diminishing off-target toxicity. Together, these data suggest that engineered bacterial toxins can be modified to have significant in vitro and in vivo therapeutic effects with high therapeutic index.

Post-GWAS functional analysis identifies CUX1 as a regulator of p16INK4a and cellular senescence.

Accumulation of senescent cells with age is an important driver of aging and age-related diseases. However, the mechanisms and signaling pathways that regulate senescence remain elusive. In this report, we performed post-genome-wide association studies (GWAS) functional studies on the CDKN2A/B locus, a locus known to be associated with multiple age-related diseases and overall human lifespan. We demonstrate that transcription factor CUX1 (Cut-Like Homeobox 1) specifically binds to an atherosclerosis-associated functional single-nucleotide polymorphism (fSNP) (rs1537371) within the locus and regulates the CDKN2A/B-encoded proteins p14ARF, p15INK4b and p16INK4a and the antisense noncoding RNA in the CDK4 (INK4) locus (ANRIL) in endothelial cells (ECs). Endothelial CUX1 expression correlates with telomeric length and is induced by both DNA-damaging agents and oxidative stress. Moreover, induction of CUX1 expression triggers both replicative and stress-induced senescence via activation of p16INK4a expression. Thus, our studies identify CUX1 as a regulator of p16INK4a-dependent endothelial senescence and a potential therapeutic target for atherosclerosis and other age-related diseases.

Discovery of Salidroside-Derivated Glycoside Analogues as Novel Angiogenesis Agents to Treat Diabetic Hind Limb Ischemia.

Therapeutic angiogenesis is a potential therapeutic strategy for hind limb ischemia (HLI); however, currently, there are no small-molecule drugs capable of inducing it at the clinical level. Activating the hypoxia-inducible factor-1 (HIF-1) pathway in skeletal muscle induces the secretion of angiogenic factors and thus is an attractive therapeutic angiogenesis strategy. Using salidroside, a natural glycosidic compound as a lead, we performed a structure-activity relationship (SAR) study for developing a more effective and druggable angiogenesis agent. We found a novel glycoside scaffold compound (C-30) with better efficacy than salidroside in enhancing the accumulation of the HIF-1α protein and stimulating the paracrine functions of skeletal muscle cells. This in turn significantly increased the angiogenic potential of vascular endothelial and smooth muscle cells and, subsequently, induced the formation of mature, functional blood vessels in diabetic and nondiabetic HLI mice. Together, this study offers a novel, promising small-molecule-based therapeutic strategy for treating HLI.

Efficacy of progesterone on threatened miscarriage: an updated meta-analysis of randomized trials.

PURPOSE: The efficacy of progesterone supplementation in the treatment of threatened miscarriage is controversial. This meta-analysis was to evaluate the correlation between progesterone and improving pregnancy outcomes in women with threatened miscarriage. METHODS: We searched PubMed, EMBASE, and the Cochrane Library for relevant randomized controlled trials (RCTs) to demonstrate the efficacy of progesterone on the threatened miscarriage pregnancy. The outcomes were miscarriage, preterm birth, and live birth. RESULTS: Nine RCTs comparing 4907 patients were included in this study. Compared with placebo or no treatment, progesterone supplementation had a relationship with a reduction in the rate of miscarriage [RR 0.70 95% Cl (0.52, 0.94)]. There was no significant difference between progesterone supplementation and placebo or no treatment in preterm birth [RR 0.87 95% Cl (0.52, 1.47) and live birth (RR 1.02 95% Cl (0.98, 1.07)]. CONCLUSION: Progesterone supplementation did not significantly improve the incidence of preterm and live birth, so progesterone treatment of threatened miscarriage may be unhelpful.

An ROS-sensitive tegafur-PpIX-heterodimer-loaded in situ injectable thermosensitive hydrogel for photodynamic therapy combined with chemotherapy to enhance the tegafur-based treatment of breast cancer.

Chemotherapy and surgery are commonly used clinical treatments for breast cancer. However, unsatisfactory therapeutic effects, unavoidable side effects, and the removal of breast tissue during surgery are still major obstacles to be overcome during breast-cancer treatment. To overcome the aforementioned issues, a biomimetic and thermosensitive hydrogel encapsulating reactive oxygen species (ROS)-sensitive tegafur (TF)-protoporphyrin IX (PpIX) heterodimers (TTP) was prepared aimed at the strategy of synergizing chemotherapy and photodynamic therapy. TF was grafted onto the photosensitizer PpIX through ROS-sensitive thioether bonds. Under 630 nm laser irradiation, the ROS concentration in tumors was increased to help drug release. The "on-demand" drug release maximized the therapeutic effects of TF and effectively reduced its toxicity. Particularly, the ROS concentration was increased, and it was expected that the tumor-cell-killing abilities of ROS could be exploited. A hydrogel formed from temperature-sensitive chitosan and silk sericin was selected as a drug carrier, which formed a drug reservoir intratumorally after intratumoral injection. Intratumoral injection gave the drug precise and long-term release behavior, which allowed for the clever avoidance of various physical and biological barriers in vivo. In vivo and in vitro studies prove that the use of this TTP hydrogel provides a new attempt to overcome the many difficulties related to breast-cancer treatment simultaneously, and this study opens up new paths for breast-cancer treatment.

Transcriptional Regulation of CD40 Expression by 4 Ribosomal Proteins via a Functional SNP on a Disease-Associated CD40 Locus.

Previously, using FREP-MS, we identified a protein complex including eight proteins that specifically bind to the functional SNP (fSNP) rs6032664 at a CD40 locus associated with autoimmune diseases. Among these eight proteins, four are ribosomal proteins RPL26, RPL4, RPL8, and RPS9 that normally make up the ribosomal subunits involved in the cellular process of protein translation. So far, no publication has shown these ribosomal proteins function as transcriptional regulators. In this work, we demonstrate that four ribosomal proteins: RPL26, RPL4, RPL8, and RPS9 are bona fide CD40 transcriptional regulators via binding to rs6032664. In addition, we show that suppression of CD40 expression by RPL26 RNAi knockdown inactivates NF-κB p65 by dephosphorylation via NF-κB signaling pathway in fibroblast-like synoviocytes (FLS), which further reduces the transcription of disease-associated risk genes such as STAT4, CD86, TRAF1 and ICAM1 as the direct targets of NF-κB p65. Based on these findings, a disease-associated risk gene transcriptional regulation network (TRN) is generated, in which decreased expression of, at least, RPL26 results in the downregulation of risk genes: STAT4, CD86, TRAF1 and ICAM1, as well as the two proinflammatory cytokines: IL1ß and IL6 via CD40-induced NF-κB signaling. We believe that further characterization of this disease-associated TRN in the CD40-induced NF-κB signaling by identifying both the upstream and downstream regulators will potentially enable us to identify the best targets for drug development.

Identification of the transcription factor Miz1 as an essential regulator of diphthamide biosynthesis using a CRISPR-mediated genome-wide screen.

Diphthamide is a unique post-translationally modified histidine residue (His715 in all mammals) found only in eukaryotic elongation factor-2 (eEF-2). The biosynthesis of diphthamide represents one of the most complex modifications, executed by protein factors conserved from yeast to humans. Diphthamide is not only essential for normal physiology (such as ensuring fidelity of mRNA translation), but is also exploited by bacterial ADP-ribosylating toxins (e.g., diphtheria toxin) as their molecular target in pathogenesis. Taking advantage of the observation that cells defective in diphthamide biosynthesis are resistant to ADP-ribosylating toxins, in the past four decades, seven essential genes (Dph1 to Dph7) have been identified for diphthamide biosynthesis. These technically unsaturated screens raise the question as to whether additional genes are required for diphthamide biosynthesis. In this study, we performed two independent, saturating, genome-wide CRISPR knockout screens in human cells. These screens identified all previously known Dph genes, as well as further identifying the BTB/POZ domain-containing transcription factor Miz1. We found that Miz1 is absolutely required for diphthamide biosynthesis via its role in the transcriptional regulation of Dph1 expression. Mechanistically, Miz1 binds to the Dph1 proximal promoter via an evolutionarily conserved consensus binding site to activate Dph1 transcription. Therefore, this work demonstrates that Dph1-7, along with the newly identified Miz1 transcription factor, are likely to represent the essential protein factors required for diphthamide modification on eEF2.

Solid-in-oil nanodispersions as a novel delivery system to improve the oral bioavailability of bisphosphate, risedronate sodium.

The aim of the current study was to modify the oral absorption of risedronate sodium (RS) using solid-in-oil nanodispersions (SONDs) technology. The oral therapeutic effect of RS is limited in vivo because of its low membrane permeability and the formation of insoluble precipitates with bivalent cations (such as Ca2+) in the gastrointestinal (GI) tract.We used SONDs to prepare medium-chain triglyceride (MCT)-based nanodispersions of the hydrophilic drug, which used the oral absorption mechanism of MCT digestion to improve bioavailability of RS in vivo. SONDs exhibited high encapsulation efficiency of RS and excellent enzymatic degradation-dependent release behavior. The result of an everted gut sac test showed that the Papp value of the SONDs was 6.29-fold (p<0.05) higher than that of RS aqueous solutions in simulated intestinal fluid containing 5 mM Ca2+, this was because MCT can be digested to form the fatty acids C8 and C10, which have an adsorption-promoting effect on RS. Further, solid-in-oil-in-water (S/O/W) emulsion droplets formedafter emulsification by bile salts and MCT digestionwere effective in disrupting epithelial tight junctions (TJs), facilitating the paracellular permeation of RS throughout the intestine. Moreover, in vivo absorption study in rats revealed that the AUC0-12h of RS in SONDs was approximately 4.56-fold (p<0.05) higher than with RS aqueous solutions at the same dose (15 mg/kg). This approach demonstrates a potential drug delivery system to improve the bioavailability of risedronate sodium.

In Vitro-In Vivo Correlation for Solid Dispersion of a Poorly Water-Soluble Drug Efonidipine Hydrochloride.

The aim of this present study was to investigate the ability of different dissolution methods to predict the in vivo performance of efonidipine hydrochloride (EFH). The solid dispersions of EFH were prepared by solvent evaporation method with HPMC-AS as matrix and urea as a pH adjusting agent. The paddle method, the open-loop, and the closed-loop flow-through cell methods were studied. In the study, Weibull's model was the best fit to explain release profiles. The pharmacokinetics behaviors of two kinds of solid dispersions with different release rate were investigated in comparison to the EFH after oral administration in rats. In vivo absorption was calculated by a numerical deconvolution method. In the study, the level A in vivo and in vitro correlation (IVIVC) was utilized. The correlation coefficient was calculated and interpreted by means of linear regression analysis (Origin.Pro.8.5 software). As a result, excellent IVIVC for solid dispersions and crude drug (r2 = 0.9352-0.9916) was obtained for the dissolution rate determined with flow-through cell open-loop system in phosphate buffer solution with 0.1% (w/v) polysorbate 80 at pH 6.5, the flow-rate of 4 mL/min. In addition, the self-assembled flow cell system had good repeatability and accuracy. The dissolution rate of the solid dispersion could be slowed down by the flow-through method, and the difference caused by preparation was significantly distinguished. The study demonstrated that flow-through cell method of the open-loop, compared with paddle method, was suitable for predicting in vivo performance of EFH solid dispersions.

The critical function of the plastid rRNA methyltransferase, CMAL, in ribosome biogenesis and plant development.

Methylation of nucleotides in ribosomal RNAs (rRNAs) is a ubiquitous feature that occurs in all living organisms. The formation of methylated nucleotides is performed by a variety of RNA-methyltransferases. Chloroplasts of plant cells result from an endosymbiotic event and possess their own genome and ribosomes. However, enzymes responsible for rRNA methylation and the function of modified nucleotides in chloroplasts remain to be determined. Here, we identified an rRNA methyltransferase, CMAL (Chloroplast MraW-Like), in the Arabidopsis chloroplast and investigated its function. CMAL is the Arabidopsis ortholog of bacterial MraW/ RsmH proteins and accounts to the N4-methylation of C1352 in chloroplast 16S rRNA, indicating that CMAL orthologs and this methyl-modification nucleotide is conserved between bacteria and the endosymbiont-derived eukaryotic organelle. The knockout of CMAL in Arabidopsis impairs the chloroplast ribosome accumulation and accordingly reduced the efficiency of mRNA translation. Interestingly, the loss of CMAL leads not only to defects in chloroplast function, but also to abnormal leaf and root development and overall plant morphology. Further investigation showed that CMAL is involved in the plant development probably by modulating auxin derived signaling pathways. This study uncovered the important role of 16S rRNA methylation mediated by CMAL in chloroplast ribosome biogenesis and plant development.

Tumor Microenvironment Stimuli-Responsive Polymeric Prodrug Micelles for Improved Cancer Therapy.

PURPOSE: The discovery of nano drug delivery system has rendered a great hope for improving cancer therapy. However, there are some inevitable obstacles that constrain its development, such as the physical and biological barriers, the toxicity of carrier materials and the physiological toxicity of drugs. Here, we report a polymeric prodrug micelle (PPM) with pH/redox dual-sensitivity, which was prepared using methoxy poly (ethylene glycol) (mPEG) with favorable biosafety to improve cancer therapy. METHOD: The tumor microenvironment stimuli-responsive PPMs were prepared and characterized in vitro and in vivo. RESULTS: Our data displayed that the PPMs with excellent biocompatibility exhibited the stimuli-responsive drug release behavior under the microenvironment of cancer cells, superior cellular internalization and lower cytotoxicity. A new method to control drug release behavior was proposed by comparing the release behavior of PPMs formed by PEG of different molecular weight. Furthermore, the fabricated PPMs exhibited the "oral-like" blood concentration curve, improved biodistribution, reduced tissue toxicity and excellent antitumor efficiency in vivo. Consistently, these results indicated that PPMs improved chemotherapeutic efficiency and reduced side effects of the model drug doxorubicin (DOX). CONCLUSION: The prepared pH/redox dual-sensitive PPM enhanced the chemotherapy effect on the tumor site while reducing the physiological toxicity of DOX. Graphical Abstract.

MicroRNA-3178 ameliorates inflammation and gastric carcinogenesis promoted by Helicobacter pylori new toxin, Tip-α, by targeting TRAF3.

BACKGROUND: Helicobacter pylori infection is the main cause of chronic gastritis, peptic ulcer, and gastric cancer. Tip-α is a newly identified carcinogenic factor present in H. pylori. TRAF3 can activate NF-κB by both canonical and noncanonical signaling pathways. In this study, we found that the expression of TRAF3 and NF-κB was upregulated, while microRNA-3178 (miR-3178) was decreased in H. pylori-positive gastric tissues but not in H. pylori-negative tissues. MATERIALS AND METHODS: GES-1 cells were incubated with 12.5 µg/mL recombinant Tip-α (rTip-α) in RPMI1640 for 2 hours. After another 24 hours, the supernatant medium was designed as inflammatory-conditioned medium (ICM) and that from the untreated control cells was designed as untreated control medium. The release of proinflammatory cytokines from GES-1 cells and proliferation of gastric cancer cells was determined by ELISA and CCK-8 kits. Cells were transfected with the mimic, inhibitor, negative control of miR-3178, or TRAF3 siRNA control siRNA. The medium was then replaced with RPMI1640, 12.5 µg/mL rTip-α, and collected, and the total cellular RNA and protein were extracted for the following detection. RESULTS: MiR-3178 mimic prevented the increasement of TRAF3 and hence decreased activation of NF-κB signals, whereas miR-3178 inhibitor could not, in GES-1 cells with Tip-α treatment. The condition medium from miR-3178 mimic transfected GES-1 cells could inhibit proliferation and induce apoptosis of inflammation-related gastric cancer cells SGC7901 and MGC803 by decreasing the production of inflammatory cytokines TNF-α and IL-6, which were secreted by GES-1 cells. CONCLUSIONS: Taken all together, Tip-α might activate NF-κB to promote inflammation and carcinogenesis by inhibiting miR-3178 expression, which directly targeting TRAF3, during H. pylori infection in gastric mucosal epithelial cells.

Evodiamine exerts anti-tumor effects against hepatocellular carcinoma through inhibiting ß-catenin-mediated angiogenesis.

Hepatocellular carcinoma (HCC) is a highly vascular tumor with high microvessel density and high levels of circulating vascular endothelial growth factor (VEGF). Thus, the angiogenesis pathway is an attractive therapeutic target for HCC. The anti-tumor effects of evodiamine, a quinolone alkaloid isolated from Euodia rutaecarpa (Juss.) Benth. (Rutaceae), were investigated in a mouse xenograft model using BALB/c nude mice, various HCC cell lines (HepG2, SMMC-7721, H22), and human umbilical vein endothelial cells (HUVECs). The effects of evodiamine on tumor volumes and weights, levels of tumor markers, angiogenesis in vivo and in vitro, cell viability, and cell migration and invasion were measured, and the mechanism through which its effects are achieved was investigated. Transcriptional regulation of VEGFa via interaction with ß-catenin was established by luciferase activity assays and electrophoretic mobility shift assays. In a subcutaneous H22 xenograft model, evodiamine inhibited tumor growth and reduced serum tumor markers and the levels of ß-catenin and VEGFa. It also blocked VEGF-induced angiogenesis in a Matrigel plug assay. Evodiamine suppressed cellular proliferation, invasion, and migration and inhibited tube formation of HUVECs. Moreover, in a concentration-dependent manner, evodiamine reduced the number of capillary sprouts from Matrigel-embedded rat thoracic aortic rings. Also, evodiamine suppressed various biomarkers of angiogenesis and the expression of ß-catenin. Evodiamine decreased ß-catenin levels activated by LiCl, which led to reduced expression of VEGFa. In addition, ß-catenin interacted with VEGFa and transcriptionally regulated VEGFa, an effect inhibited by evodiamine in HCCs. Moreover, in an SMMC-7721 xenograft model, evodiamine suppressed tumor growth, various biomarkers of angiogenesis, and the levels of ß-catenin and VEGFa. Evodiamine has anti-tumor effects on HCCs through inhibiting ß-catenin, which interacts with and reduces VEGFa expression, thus inhibiting angiogenesis. These results indicate that evodiamine, which inhibits cellular invasion and migration and blocks angiogenesis, is a potential therapeutic agent for HCCs.