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Aloperine (ALO), a quinolizidine‐type alkaloid isolated from a natural Chinese herb, has shown promising antitumor effects. Nevertheless, its common mechanism of action and specific target remain elusive. Here, it is demonstrated that ALO inhibits the proliferation and migration of non‐small cell lung cancer cell lines in vitro and the tumor development in several mouse tumor models in vivo. Mechanistically, ALO inhibits the fusion of autophagosomes with lysosomes and the autophagic flux, leading to the accumulation of sequestosome‐1 (SQSTM1) and production of reactive oxygen species (ROS), thereby inducing tumor cell apoptosis and preventing tumor growth. Knockdown of SQSTM1 in cells inhibits ROS production and reverses ALO‐induced cell apoptosis. Furthermore, VPS4A is identified as a direct target of ALO, and the amino acids F153 and D263 of VPS4A are confirmed as the binding sites for ALO. Knockout of VPS4A in H1299 cells demonstrates a similar biological effect as ALO treatment. Additionally, ALO enhances the efficacy of the anti‐PD‐L1/TGF‐β bispecific antibody in inhibiting LLC‐derived subcutaneous tumor models. Thus, ALO is first identified as a novel late‐stage autophagy inhibitor that triggers tumor cell death by targeting VPS4A. [ABSTRACT FROM AUTHOR]

Background and Purpose: Liver fibrosis is a wound‐healing reaction which is the main cause of chronic liver diseases worldwide. The activated hepatic stellate cell (aHSC) is the main driving factor in the development of liver fibrosis. Inhibiting autophagy of aHSC can prevent the progression of liver fibrosis, but inhibiting autophagy of other liver cells has opposite effects. Hence, targeted inhibition of autophagy in aHSC is quite necessary for the treatment of liver fibrosis, which prompts us to explore the targeted delivery system of small molecule autophagy inhibitor hydroxychloroquine (HCQ) that can target aHSC and alleviate the liver fibrosis. Methods: The delivery system of HCQ@retinol‐liposome nanoparticles (HCQ@ROL‐LNPs) targeting aHSC was constructed by the film dispersion and pH‐gradient method. TGF‐β‐induced HSC activation and thioacetamide (TAA)‐induced liver fibrosis mice model were established, and the targeting ability and therapeutic effect of HCQ@ROL‐LNPs in liver fibrosis were studied subsequently in vitro and in vivo. Results: HCQ@ROL‐LNPs have good homogeneity and stability. They inhibited the autophagy of aHSC selectively by HCQ and reduced the deposition of extracellular matrix (ECM) and the damage to other liver cells. Compared with the free HCQ and HCQ@LNPs, HCQ@ROL‐LNPs had good targeting ability, showing enhanced therapeutic effect and low toxicity to other organs. Conclusion: Construction of HCQ@ROL‐LNPs delivery system lays a theoretical and experimental foundation for the treatment of liver fibrosis and promotes the development of clinical therapeutic drugs for liver diseases. [ABSTRACT FROM AUTHOR]

Autophagy, a lysosome‐involved degradation pathway, as a self‐protective cellular process, always weakens the efficiency of tumor therapies. Herein, for the first time, the biodegradable copper (Cu) ions doped layered double hydroxide (Cu‐LDH) nanoparticles are reported for cancer immunotherapy via lysosomal rupture‐mediated "Broken Window Effect". Only injection of Cu‐LDH single therapeutic agent achieves various organelles destruction after lysosomal rupture, as well as the abnormal aggregation of Cu ions in tumor cells for cuproptosis and pyroptosis. More importantly, autophagy inhibition caused by lysosomal rupture improves Cu ions overload‐mediated cuproptosis and pyroptosis by blocking the lysosome‐mediated bulk degradation pathway, leading to good anti‐tumor immune responses and ultimately high‐efficiency tumor growth inhibition. This lysosomal rupture‐mediated "Broken Window Effect" provides a new paradigm for the autophagy enhanced tumor therapy. [ABSTRACT FROM AUTHOR]

Chemo‐dynamic therapy (CDT) based on the Fenton or Fenton‐like reaction has emerged as a promising approach for cancer treatment. However, autophagy‐mediated self‐protection mechanisms of cancer cells pose a significant challenge to the efficacy of CDT. Herein, we developed metal‐DNA nanocomplexes (DACs‐Mn) to enhance CDT via DNAzyme inhibition of autophagy. Specifically, Mn‐based catalyst in DACs‐Mn was used to generate highly hydroxyl radicals (⋅OH) that kill cancer cells, while the ATG5 DNAzyme incorporated into DACs‐Mn inhibited the expression of autophagy‐associated proteins, thereby improving the efficacy of CDT. By disrupting the self‐protective pathway of cells under severe oxidative stress, this novel approach of DACs‐Mn was found to synergistically enhance CDT in both in vitro and in vivo models, effectively amplifying tumor‐specific oxidative damage. Notably, the Metal‐DNA nanocomplexes can also induce immunogenic cell death (ICD), thereby inhibiting tumor metastasis. Specifically, in a bilateral tumor model in mice, the combined approach of CDT and autophagy inhibition followed by immune checkpoint blockade therapy shown significant potential as a novel and effective treatment modality for primary and metastatic tumors. [ABSTRACT FROM AUTHOR]

Universal chemotherapy in glioblastoma patients causes chemoresistance and further limits immune cells by creating an immunosuppressive tumor microenvironment that are difficult to solve by single‐drug therapeutic approaches. Here, this work designs hybrid drug‐loaded nanoliposomes by co‐loading the chemotherapeutic drug temozolomide (TMZ) and nitric oxide (NO) prodrug JS‐K with sphingosine‐1‐phosphate molecules (S1P) on the surface. The S1P‐S1P receptors axis endows nanoliposomes with rapid targeting and lysosomal escaping capability. Then, fine‐tuned TMZ release and NO gas production following JS‐K release in glioma microenvironment decrease chemoresistance and increase tumor immunogenicity through inhibiting the cellular autophagy as well as inducing mitochondrial dysfunction. RNA sequencing analysis demonstrates that the NO gas generation reprograms glioma microenvironment immune and inflammation‐related pathways. The positive immune response in turn effectively activates the enhanced efficacy of chemotherapy. NO gas generated nanoliposomes thus have attractive paradigm‐shifting applications in the treatment of "cold" tumors across a range of immunosuppressive indications. [ABSTRACT FROM AUTHOR]

Scars are common complications of burns and trauma, resulting in mental trauma, physical pain, and a heavy financial burden for patients. Specific and effective anti‐scarring drugs are lacking in clinical practice. Phytochemicals are easily accessible, low in toxicity, and have various biological and pharmacological properties. Oxymatrine is a phytochemical that regulates autophagy networks. Autophagy is closely related to the maintenance, activity, differentiation, and life‐death of skin fibroblasts during wound repair, which results in pathological scars. We hypothesised that oxymatrine may promote hypertrophic scar repair by inhibiting fibroblast autophagy. In vitro studies showed that inhibition of autophagy by oxymatrine decreased viability and collagen metabolism, and increased apoptosis of human scar fibroblasts (HSFs). In vivo studies showed that inhibition of autophagy by oxymatrine promoted scar repair, resulting in a significantly improved final outcome of the hypertrophic scars, a smaller scar area, decreased epidermal and dermal thickness, and a significant downregulation of CK10, P63, collagen I, α‐SMA, and TGF‐β1. In summary, oxymatrine promoted hypertrophic scar repair by decreasing HSF viability and collagen, and inducing apoptosis via autophagy inhibition. This study provides a new perspective on the mechanism of hypertrophic burn scar formation, as well as key scientific data for the application of the phytochemical oxymatrine as a new method for the prevention and treatment of hypertrophic scars. [ABSTRACT FROM AUTHOR]

Targeted delivery of drug‐loaded nanoparticles to brain tumors is exceptionally difficult due to the blood‐brain barrier (BBB). In addition, several chemotherapeutic drugs induce autophagy, which protects the cells from apoptosis and mitigates the therapeutic effect. A novel "all‐in‐one" nanoparticles (AMPTL) consisting of endogenous reactive oxygen species‐cleavable thioketal linkers conjugated to paclitaxel (PTX) and autophagy inhibitor 3‐methyladenine, and angiopep‐2 peptide‐modified DSPE‐PEG2K is developed. AMPTL inhibits autophagy in the C6 glioma cells, as indicated by fewer autophagic vesicles, lower LC3‐II expression and accumulation of SQSTM1/P62, and significantly upregulates p53 and the pro‐apoptotic Bax and cleaved caspase‐3 proteins. In addition, AMPTL treatment induces cell cycle arrest at the G2/M phase. Thus, inhibition of autophagy in the AMPTL‐treated glioma cells sensitizes them to PTX‐induced cell cycle arrest and apoptosis. Furthermore, focused pulse ultrasound and microbubbles enhances the delivery of AMPTL to intracranial glioma tissues by reversibly opening the BBB, which significantly inhibits xenograft growth and markedly improves survival rates of the tumor‐bearing mice. Taken together, combining non‐invasive BBB opening with autophagy inhibitors and chemotherapeutic drugs can achieve cascade‐amplifying synergistic therapeutic effects against glioma. [ABSTRACT FROM AUTHOR]

Polydopamine (PDA) has attracted much attention recently due to its strong adhesion capability to most substrates. After combining with organic (such as organic metal framework, micelles, hydrogel, polypeptide copolymer) or inorganic nanomaterials (such as gold, silicon, carbon), polydopamine‐based nanoparticles (PDA NPs) exhibit the merging of characteristics. Until now, the preparation methods, polymerization mechanism, and photothermal therapy (PTT) or chemotherapy (CT) applications of PDA NPs have been reported detailly. Since the PTT or CT treatment process is often accompanied by exogenous stimuli, tumor cells usually induce pro‐survival autophagy to protect the cells from further damage, which will weaken the therapeutic effect. Therefore, an in‐depth understanding of PDA NPs modulated PTT, CT, and autophagy is required. However, this association is rarely reviewed. Herein, we briefly described the relationship between PTT/CT, autophagy, and tumor treatment. Then, the outstanding performances of PDA NPs in PTT/CT and their combination with autophagy inhibitors for tumor synergistic therapy have been summarized. This work is expected to shed light on the multi‐strategy antitumor therapy applications of PDA NPs. [ABSTRACT FROM AUTHOR]

BACKGROUND Autophagy plays an important role in eukaryotes. We investigated its role in the pine wood nematode (PWN), Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD), to find promising control strategies against PWD. RESULTS: We analysed the expression levels of PtRBOH1 and PtRBOH2, which regulate reactive oxygen species (ROS) metabolism, in Pinus thunbergii and the expression of three autophagy genes, BxATG5, BxATG9 and BxATG16, in PWN by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR), and measured the content of H2O2, the main product of ROS metabolism, in pine stem. There was a correlation between the expression of autophagy genes in PWN and pine ROS metabolism during early infection. We also found that oxidative stress induces autophagy in PWN according to qRT‐PCR, transmission electron microscopy and Western blot analyses. Inhibition of autophagy by 3‐methyladenine or silencing of the autophagy genes BxATG9 and BxATG16 in PWN showed that autophagy is essential for feeding, fecundity, egg hatching and survival of PWN under oxidative stress, confirming the importance of autophagy in the antioxidant defences of PWN. Similarly, we demonstrated that autophagy contributes to the virulence of PWN. Moreover, PWN likely ameliorates oxidative damage by enhancing the activities of the peroxidase and catalase antioxidant pathways when autophagy is inhibited. CONCLUSION: Autophagy contributes to resistance to the oxidative stress induced by pine ROS metabolism, thus promoting infection by PWN. Our findings clarify the defence mechanisms of PWN and the pathogenesis of PWD, and provide promising hints for control of PWD by blocking autophagy. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Multifunctional human transcriptional positive co‐activator 4 (PC4) is a bona fide nonhistone component of the chromatin and plays a pivotal role in the process of chromatin compaction and functional genome organization. Knockdown of PC4 expression causes a drastic decompaction which leads to open conformation of the chromatin, and thereby altered nuclear architecture, defects in chromosome segregation and changed epigenetic landscape. Interestingly, these defects do not induce cellular death but result in enhanced cellular proliferation, possibly through enhanced autophagic activity. Moreover, PC4 depletion confers significant resistance to gamma irradiation. Exposure to gamma irradiation further induced autophagy in these cells. Inhibition of autophagy by small molecule inhibitors as well as by silencing of a critical autophagy gene drastically reduces the ability of PC4 knockdown cells to survive. On the contrary, complementation with wild‐type PC4 could reverse this phenomenon, confirming the process of autophagy as the key mechanism for radiation resistance in the absence of PC4. These data connect the unexplored role of chromatin architecture in regulating autophagy during stress conditions such as radiation. [ABSTRACT FROM AUTHOR]

Abstract: Targeting protein degradation is recognized as a valid approach to cancer therapy. The ubiquitin–proteasome system (UPS) and the autophagy–lysosome pathway are two major pathways for intracellular protein degradation. Proteasome inhibitors such as bortezomib are clinically approved for treating malignancies, but to date, they are still unsatisfactory for cancer therapy. This study identifies titania‐coated gold nano‐bipyramid (NBP/TiO2) nanostructures as an autophagic flux inhibitor, as the smallest NBP/TiO2 nanostructures induce significant autophagosome accumulation in human glioblastoma U‐87 MG cells via blocking the autophagosome–lysosome fusion process and inhibiting lysosomal degradation. Further study indicates that NBP/TiO2 nanostructures reduce the intracellular level of mature cathepsin B and directly inhibit the proteolytic activity of cathepsin B, thereby further inhibiting trypsin‐like proteolytic activity, which is a potential cotarget for UPS inhibition. NBP/TiO2 nanostructures interact synergistically with bortezomib to suppress the viability of U‐87 MG cells, as the combined treatment synergistically induces the intracellular accumulation of ubiquitinated protein and endoplasmic reticulum stress. In addition, photothermal therapy further synergistically reduces the cell viability. In summary, this study suggests that NBP/TiO2 nanostructures function as a promising anticancer agent in combination with proteasome inhibitors. [ABSTRACT FROM AUTHOR]

Expression profiles revealed miR-1299 downregulation concomitant with arginase-2 ( ARG2) upregulation in hyperpigmented skin of melasma patients. Opposite regulation of tyrosinase and PMEL17 by miR-1299 and inverse relationship between miR-1299 and ARG2 expression denoted a role of miR-1299 in pigmentation with ARG2 as a miR-1299 target. ARG2 overexpression or knock-down in keratinocytes, the main source of ARG2 in epidermis, positively regulated tyrosinase and PMEL17 protein levels, but not mRNA levels or melanosome transfer. ARG2 overexpression in keratinocytes reduced autophagy equivalent to 3- MA, an autophagy inhibitor which also increased tyrosinase and PMEL17 protein levels, whereas ARG2 knock-down induced opposite results. Autophagy inducer rapamycin reduced ARG2-increased tyrosinase and PMEL17 protein levels. Also, autophagy was reduced in late passage-induced senescent keratinocytes showing ARG2 upregulation. ARG2, but not 3- MA, stimulated keratinocyte senescence. These results suggest that ARG2 reduces autophagy in keratinocytes by stimulating cellular senescence, resulting in skin pigmentation by reducing degradation of transferred melanosomes. [ABSTRACT FROM AUTHOR]

This editorial highlights current developments and new paradigms in the management of desmoid tumor patients as developed by the Desmoid Tumor Working Group. The article "Autophagy Inhibition Overcomes Sorafenib Resistance in S45F‐Mutated Desmoid Tumors" is put into perspective regarding a new emerging drug, sorafenib, which is proven to be active in desmoid tumor in a recent phase 3 trial. [ABSTRACT FROM AUTHOR]