Latest ArticlesDuring cancer treatment, chemotherapeutic drugs always result in severe side-effects and drug resistance. Therefore, combining cheomtherapy with other therapeutic modalities, such as photodynamic therapy (PDT) and designing an activable platform is promising for precise and efficient anticancer treatment. Herein, we report a "pro-drug-photosensitizer" agent, LMB-S-CPT, bearing a disulfide bond as the glutathione (GSH)-activatable linker. LMB-S-CPT can be selectively activated by GSH to release activated drug, camptothecin (CPT), for chemotherapy and activated photosensitizer, methylene blue (MB), for PDT. LMB-S-CPT exhibits excellent tumor-activatable performance when injected into tumor-bearing mice, as well as specific cancer therapy with negligible toxic side effects. The activatable pro-drug-photosensitizer offers a new strategy for chemo-photodynamic therapy and displays precise, selective and excellent antitumor effect.
By integrating one strain-many compounds (OSMAC) and LC–MS-based molecular networking strategies, distachydrimanes A–F (1–6), six novel phenylspirodrimane dimers and hybrids representing two types of unprecedented terpenoid-polyketide hybrid skeletons, were isolated from the modified fermented rice substrate of a coral-derived fungus Stachybotrys chartarum. All the structures incorporating their absolute configurations were elucidated based on comprehensive spectroscopic analyses, mainly including HRESIMS and NMR data, single-crystal X-ray diffraction (Cu Kα), and comparison of the experimental electronic circular dichroism (ECD) data. Architecturally, compounds 1–6 represent an unprecedented class of dimeric phenylspirodrimanes with an unexpected C-18–C-23′ linkage, of which compounds 1–3 also feature an unexpected 5-methyl-1, 3-benzenediol moiety via a carbon-carbon linkage. The bioactivity assay demonstrated that compounds 1, 5 and 6 induced cell proliferation inhibition, G0/G1 cell cycle arrest, senescence and mitochondrial-mediated apoptosis in L1210 cells, highlighting their potentials as a new category of anticancer agents.
Cisplatin is the first-line drug for treatment of various solid tumors including breast cancer due to the broad anti-tumor spectrum and strong anti-tumor effect. However, serious side effects and long-term medication of reduced sensitivity by high GSH in tumor cells have severely restricted its further clinical application. Herein, a GSH-depleted Pt(Ⅳ) prodrug (Platin B) based on cisplatin and 4-carboxylphenylboronic acid pinacol ester was prepared to solve the problems. As an excellent GSH scavenger, 4-carboxylphenylboronic acid pinacol ester could be activated by intracellular redox reactions to release quinone methide, thereby amplifying oxidative stress and leading to breast cancer ferroptosis therapy. Interestingly, the consumption of GSH can also reduce cisplatin inactivation, enhance the sensitivity of tumor cells to cisplatin and efficiently induce apoptosis/ferroptosis. This work highlights the use of GSH scavenger for triggering ferroptotic cell death in breast cancer.
Breast cancer is the most prevalent cancer in women, and it was hard to prevent or diagnose at an early stage. Thus, it is imperative to develop advanced therapeutics for effective treatment. Herein, a targeted daunorubicin (DNR) and cytarabine (ara-C) co-delivery system was developed by modifying the ara-C loaded liposomes (LIP-ara-C) with the hyaluronic acid-DNR (HA-DNR) prodrugs. The co-assembled hybrid nanoparticles (HA-DNR/LIP-ara-C HNPs) exhibited good serum and storage stability with an average diameter of approximately 100 nm. By specifically binding to the CD44 receptors that overexpressed on cancer cells, these HNPs could be uptake via endocytosis and accumulate intracellularly, in which an optimized DNR and ara-C combination at a molar ratio of 1:5 could generate enhanced synergistic effects with reduced dose-related toxicity on cancer cells.
It is of great significance to develop effective antibacterial agents and methods to combat drug resistant bacterial infections due to its increasing threaten to human health and the ineffectiveness of antibiotics. Herein, a multifunctional hybrid nano-assembly (M1-Fe NPs) based on conjugated oligomer and ferrous ion was engineered with favorable bactericidal activity for synergetic antibacterial therapy. The chelation of ferrous ion not only enhances the photothermal conversion efficiency of M1 but also endows the nano-assembly with catalytic capability of transferring H2O2 into stronger oxidant hydroxyl radicals (•OH). Meanwhile, the generated heat can further promote the Fenton reaction activity. By generating cytotoxic heat and oxidative •OH, M1-Fe NPs can effectively kill Staphylococcus aureus in vitro and in vivo with the aid of low dosage of H2O2. The work provides a new multifunctional platform for combinational drug resistant antibacterial therapy and even antitumor therapy.
Clear cell renal cell carcinoma (ccRCC) is a heterogeneous malignancy with poor prognosis. Methylation of the N6 position of adenosine (m6A), the most common epigenetic modification in both messenger RNAs and noncoding RNAs, has been reported to regulate the initiation and progression of ccRCC. However, whether and how m6A-related long noncoding RNAs (m6ArlncRNAs) signify the progression of ccRCC remain unclear. We found m6ArlncRNAs are effective signatures illustrating immune landscape and risk stratification in ccRCC. We identified two differently expressed m6ArlncRNAs (DEm6ArlncRNAs), AC008870.2 and EMX2OS, as independent risk factors for overall survival of ccRCC patients, by applying stringent variable selection procedure to data from the Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma project. The risk score generated from the DEm6ArlncRNA expression categorizes patients into either high or low-risk groups, between which, enrichment analysis indicated an enrichment in immunerelated pathways. Under different DEm6ArlncRNA transcription pattern, the two risk groups differ in immune cell population composition and expression levels of therapy targeting genes. Nanoparticle is satisfactory strategy to delivering therapeutic drugs. For further clinical translation, we designed a novel nanoparticle delivery system packaged STM2457 (STM@8P4 NPs), which selectively inhibits AC008870.2- correlated m6A writer. STM@8P4 NPs loaded drug successfully with uniform particle size, long-term stability and high release efficiency. STM@8P4 NPs can easily enter ccRCC cells and showed a highly efficient ccRCC killing activity in vitro. Our results therefore indicate that m6ArlncRNAs expression can depict tumor microenvironment, predict prognosis for ccRCC patient and give hint to therapeutic strategies in ccRCC.
Protein-based drugs have received extensive attention in the field of drug research in recent years. However, protein-based drug activity is difficult to maintain during oral delivery, which limits its application. This study developed bifunctional oral lipid polymer hybrid nanoparticles (R8-PEG-PPNPs) that deliver superoxide dismutase (SOD) for the treatment of ulcerative colitis (UC). R8-PEG-PPNPs was composed of PCADK, PLGA, lecithin, and co-modified with stearic acid-octa-arginine and polyethylene glycol. The nanoparticles (NPs) are uniformly dispersed with a complete spherical structure. In vitro stability and release studies showed that R8-PEG-PPNPs exhibited good stability and protection. In vitro cell culture experiments demonstrated that R8-PEG-PPNPs as carriers have no significant toxic effects on cells at concentration below 1000 µg/mL and promote cellular uptake. In experiments with ulcerative colitis mice, R8-PEG- PPNPs were able to enhance drug absorption by intestinal epithelial cells and accumulate effectively at the site of inflammation. Its therapeutic effect further demonstrates that R8-PEG-PPNPs are a promising delivery system for oral delivery of protein-based drugs.
Electrocatalytic nitrogen reduction reaction (NRR) is an environmentally friendly method for sustainable ammonia synthesis under ambient conditions. Searching for efficient NRR electrocatalysts with high activity and selectivity is currently urgent but remains great challenge. Herein, we systematically investigate the NRR catalytic activities of single and double transition metal atoms (TM = Fe, Co, Ni and Mo) anchored on g-C6N6 monolayers by performing first-principles calculation. Based on the stability, activity, and selectivity analysis, Mo2@g-C6N6 monolayer is screened out as the most promising candidate for NRR. Further exploration of the reaction mechanism demonstrates that the Mo dimer anchored on g-C6N6 can sufficiently activate and efficiently reduce the inert nitrogen molecule to ammonia through a preferred distal pathway with a particularly low limiting potential of -0.06 V. In addition, we find that Mo2@g-C6N6 has excellent NRR selectivity over the competing hydrogen evolution reaction, with the Faradaic efficiency being 100%. Our work not only predicts a kind of ideal NRR electrocatalyst but also encouraging more experimental and theoretical efforts to develop novel double-atom catalysts (DACs) for NRR.
Rechargeable aqueous zinc-ion batteries have attracted extensive interest because of low cost and high safety. However, the relationship between structure change of cathode and the zinc ion storage mechanism is still complex and challenging. Herein, open-structured ferric vanadate (Fe2V4O13) has been developed as cathode material for aqueous zinc-ion batteries. Intriguingly, two zinc ion storage mechanism can be observed simultaneously for the Fe2V4O13 electrode, i.e., classical intercalation/deintercalation storage mechanism in the tunnel structure of Fe2V4O13, and reversible phase transformation from ferric vanadate to zinc vanadate, which is verified by combined studies using various in-situ and ex-situ techniques. As a result, the Fe2V4O13 cathode delivers a high discharge capacity of 380 mAh/g at 0.2 A/g, and stable cyclic performance up to 1000 cycles at 10 A/g in the operating window of 0.2–1.6 V with 2 mol/L Zn(CF3SO3)2 aqueous solution. Moreover, the assembled Fe2V4O13//Zn flexible quasi-solid-state battery also exhibits a relatively high mechanical strength and good cycling stability. The findings reveal a new perspective of zinc ion storage mechanism for Fe2V4O13, which may also be applicable to other vanadate cathodes, providing a new direction for the investigation and design of zinc-ion batteries.
Solid-state batteries with high energy density and safety are promising next-generation battery systems. However, lithium oxide and lithium sulfide electrolytes suffer low ionic conductivity and poor electrochemical stability, respectively. Lithium halide solid electrolyte shows high conductivity and good compatibility with the pristine high-voltage cathode but limited applications due to the high price of rare metal. Zr-based lithium halides with low cost and high stability possess great potential. Herein, a small amount of In3+ is introduced in Li2ZrCl6 to synthesize Li2.25Zr0.75In0.25Cl6 electrolytes with a high room temperature Li-ion conductivity of 1.08 mS/cm. Solid-state batteries using Li2.25Zr0.75In0.25Cl6/Li5.5PS4.5Cl1.5 bilayer solid electrolytes combined with Li-In anode and pristine LiNi0.7Mn0.2Co0.1O2 cathode deliver high initial discharge capacities under different cut-off voltages. This work provides an effective strategy for enhancing the conductivity of Li2ZrCl6 electrolytes, promoting their applications in solid-state batteries.