ESCRT-III-mediated membrane repair in cell death and tumor resistance

Assessment of silver nanoparticles' antitumor effects: Insights into cell number, viability, and morphology of glioblastoma and prostate cancer cells

Silver nanoparticles (AgNPs) hold promise for cancer therapy. This study aimed to evaluate their impact on tumor and non-tumor cell number, viability, and morphology. Antitumor activity was tested on U-87MG (glioblastoma) and DU-145 (prostate cancer) cell lines. Treatment with AgNPs notably reached a reduction of U-87MG and DU-145 cell growth by 89.30% and 79.74%, respectively, resulting in slower growth rates. AgNPs induced DNA damage, evidenced by reduced nuclear area and DNA content via fluorescent image-based analyses. Conversely, HFF-1 non-tumor cells displayed no significant changes post-AgNPs exposure. Viability assays revealed substantial reductions in U-87MG and DU-145 cells (79% and 63% in MTT assays, 30% and 52.2% in high-content analyses), while HFF-1 cells exhibited lower sensitivity. Tumor cells had notably lower IC50 values than non-tumor cells, indicating selective susceptibility. Transmission electron microscopy (TEM) showed morphological changes post-AgNPs administration, including increased vacuoles, myelin figures, membrane ghosts, cellular extravasation, and membrane projections. The findings suggest the potential of AgNPs against glioblastoma and prostate cancer, necessitating further exploration across other cancer cell lines.

Beyond Death: Unmasking the Intricacies of Apoptosis Escape

Apoptosis, or programmed cell death, maintains tissue homeostasis by eliminating damaged or unnecessary cells. However, cells can evade this process, contributing to conditions such as cancer. Escape mechanisms include anoikis, mitochondrial DNA depletion, cellular FLICE inhibitory protein (c-FLIP), endosomal sorting complexes required for transport (ESCRT), mitotic slippage, anastasis, and blebbishield formation. Anoikis, triggered by cell detachment from the extracellular matrix, is pivotal in cancer research due to its role in cellular survival and metastasis. Mitochondrial DNA depletion, associated with cellular dysfunction and diseases such as breast and prostate cancer, links to apoptosis resistance. The c-FLIP protein family, notably CFLAR, regulates cell death processes as a truncated caspase-8 form. The ESCRT complex aids apoptosis evasion by repairing intracellular damage through increased Ca2+ levels. Antimitotic agents induce mitotic arrest in cancer treatment but can lead to mitotic slippage and tetraploid cell formation. Anastasis allows cells to resist apoptosis induced by various triggers. Blebbishield formation suppresses apoptosis indirectly in cancer stem cells by transforming apoptotic cells into blebbishields. In conclusion, the future of apoptosis research offers exciting possibilities for innovative therapeutic approaches, enhanced diagnostic tools, and a deeper understanding of the complex biological processes that govern cell fate. Collaborative efforts across disciplines, including molecular biology, genetics, immunology, and bioinformatics, will be essential to realize these prospects and improve patient outcomes in diverse disease contexts.

Ferroptosis: principles and significance in health and disease

Ferroptosis, an iron-dependent form of cell death characterized by uncontrolled lipid peroxidation, is governed by molecular networks involving diverse molecules and organelles. Since its recognition as a non-apoptotic cell death pathway in 2012, ferroptosis has emerged as a crucial mechanism in numerous physiological and pathological contexts, leading to significant therapeutic advancements across a wide range of diseases. This review summarizes the fundamental molecular mechanisms and regulatory pathways underlying ferroptosis, including both GPX4-dependent and -independent antioxidant mechanisms. Additionally, we examine the involvement of ferroptosis in various pathological conditions, including cancer, neurodegenerative diseases, sepsis, ischemia-reperfusion injury, autoimmune disorders, and metabolic disorders. Specifically, we explore the role of ferroptosis in response to chemotherapy, radiotherapy, immunotherapy, nanotherapy, and targeted therapy. Furthermore, we discuss pharmacological strategies for modulating ferroptosis and potential biomarkers for monitoring this process. Lastly, we elucidate the interplay between ferroptosis and other forms of regulated cell death. Such insights hold promise for advancing our understanding of ferroptosis in the context of human health and disease.

Tumor-Targeting Multiple Metabolic Regulations for Bursting Antitumor Efficacy of Chemodynamic Therapy

Interfering with intratumoral metabolic processes is proven to effectively sensitize different antitumor treatments. Here, a tumor-targeting catalytic nanoplatform (CQ@MIL-GOX@PB) loading with autophagy inhibitor (chloroquine, CQ) and glucose oxidase (GOX) is fabricated to interfere with the metabolisms of tumor cells and tumor-associated macrophages (TAMs), then realizing effective antitumor chemodynamic therapy (CDT). Once accumulating in the tumor site with the navigation of external biotin, CQ@MIL-GOX@PB will release Fe ions and CQ in the acid lysosomes of tumor cells, the latter can sensitize Fe ions-involved antitumor CDT by blocking the autophagy-dependent cell repair. Meanwhile, the GOX component will consume glucose, which not only generates many H2O2 for CDT but also once again decelerates the tumor repair process by reducing energy metabolism. What is more, the release of CQ can also drive the NO anabolism of TAMs to further sensitize CDT. This strategy of multiple metabolic regulations is evidenced to significantly improve the antitumor effect of traditional CDT nanoagents and might provide a new sight to overcome the bottlenecks of different antitumor treatments.

Pyroptosis Signature Gene CHMP4B Regulates Microglia Pyroptosis by Inhibiting GSDMD in Alzheimer's Disease

In this study, we aimed to work through the key genes involved in the process of pyroptosis in Alzheimer's disease (AD) to identify potential biomarkers using bioinformatics technology and further explore the underlying molecular mechanisms. The transcriptome data of brain tissue in AD patients were screened from the GEO database, and pyroptosis-related genes were analyzed. The functions of differential genes were analyzed by enrichment analysis and protein-protein interaction. The diagnostic model was established using LASSO and logistic regression analysis, and the correlation of clinical data was analyzed. Based on single-cell analysis of brain tissues of patients with AD, immunofluorescence and western blotting were used to explore the key cells affected by the hub gene. After GSEA, qRT-PCR, western blotting, LDH, ROS, and JC-1 were used to investigate the potential mechanism of the hub gene on pyroptosis. A total of 15 pyroptosis differentially expressed genes were identified. A prediction model consisting of six genes was established by LASSO and logistic regression analysis, and the area under the curve was up to 0.81. As a hub gene, CHMP4B was negatively correlated with the severity of AD. CHMP4B expression was decreased in the hippocampal tissue of patients with AD and mice. Single-cell analysis showed that CHMP4B was downregulated in AD microglia. Overexpression of CHMP4B reduced the release of LDH and ROS and restored mitochondrial membrane potential, thereby alleviating the inflammatory response during microglial pyroptosis. In summary, CHMP4B as a hub gene provides a new strategy for the diagnosis and treatment of AD.

DAMP sensing and sterile inflammation: intracellular, intercellular and inter-organ pathways

Damage-associated molecular patterns (DAMPs) are endogenous molecules that are released from host cells as a result of cell death or damage. The release of DAMPs in tissues is associated with loss of tissue homeostasis. Sensing of DAMPs by innate immune receptors triggers inflammation, which can be beneficial in initiating the processes that restore tissue homeostasis but can also drive inflammatory diseases. In recent years, the sensing of intracellular DAMPs has received extensive attention in the field of sterile inflammation. However, emerging studies have shown that DAMPs that originate from neighbouring cells, and even from distal tissues or organs, also mediate sterile inflammatory responses. This multi-level sensing of DAMPs is crucial for intercellular, trans-tissue and trans-organ communication. Here, we summarize how DAMP-sensing receptors detect DAMPs from intracellular, intercellular or distal tissue and organ sources to mediate sterile inflammation. We also discuss the possibility of targeting DAMPs or their corresponding receptors to treat inflammatory diseases.

CHMP5 attenuates osteoarthritis via inhibiting chondrocyte apoptosis and extracellular matrix degradation: involvement of NF-κB pathway

BACKGROUND

Osteoarthritis (OA), the most common joint disease, is linked with chondrocyte apoptosis and extracellular matrix (ECM) degradation. Charged multivesicular body protein 5 (CHMP5), a member of the multivesicular body, has been reported to serve as an anti-apoptotic protein to participate in leukemia development. However, the effects of CHMP5 on apoptosis and ECM degradation in OA remain unclear.

METHODS

In this study, quantitative proteomics was performed to analyze differential proteins between normal and OA patient articular cartilages. The OA mouse model was constructed by the destabilization of the medial meniscus (DMM). In vitro, interleukin-1 beta (IL-1β) was used to induce OA in human chondrocytes. CHMP5 overexpression and silencing vectors were created using an adenovirus system. The effects of CHMP5 on IL-1β-induced chondrocyte apoptosis were investigated by CCK-8, flow cytometry, and western blot. The effects on ECM degradation were examined by western blot and immunofluorescence. The potential mechanism was explored by western blot and Co-IP assays.

RESULTS

Downregulated CHMP5 was identified by proteomics in OA patient cartilages, which was verified in human and mouse articular cartilages. CHMP5 overexpression repressed cell apoptosis and ECM degradation in OA chondrocytes. However, silencing CHMP5 exacerbated OA chondrocyte apoptosis and ECM degradation. Furthermore, we found that the protective effect of CHMP5 against OA was involved in nuclear factor kappa B (NF-κB) signaling pathway.

CONCLUSIONS

This study demonstrated that CHMP5 repressed IL-1β-induced chondrocyte apoptosis and ECM degradation and blocked NF-κB activation. It was shown that CHMP5 might be a novel potential therapeutic target for OA in the future.

Ferroptosis: a new hunter of hepatocellular carcinoma

Ferroptosis is an iron ion-dependent, regulatory cell death modality driven by intracellular lipid peroxidation that plays a key role in the development of HCC. Studies have shown that various clinical agents (e.g., sorafenib) have ferroptosis inducer-like effects and can exert therapeutic effects by modulating different key factors in the ferroptosis pathway. This implies that targeting tumor cell ferroptosis may be a very promising strategy for tumor therapy. In this paper, we summarize the prerequisites and defense systems for the occurrence of ferroptosis and the regulatory targets of drug-mediated ferroptosis action in HCC, the differences and connections between ferroptosis and other programmed cell deaths. We aim to summarize the theoretical basis, classical inducers of ferroptosis and research progress of ferroptosis in HCC cells, clued to the treatment of HCC by regulating ferroptosis network. Further investigation of the specific mechanisms of ferroptosis and the development of hepatocellular carcinoma and interventions at different stages of hepatocellular carcinoma will help us to deepen our understanding of hepatocellular carcinoma, with a view to providing new and more precise preventive as well as therapeutic measures for patients.

Emerging roles of lysosome homeostasis (repair, lysophagy and biogenesis) in cancer progression and therapy

In the era of personalized therapy, precise targeting of subcellular organelles holds great promise for cancer modality. Taking into consideration that lysosome represents the intersection site in numerous endosomal trafficking pathways and their modulation in cancer growth, progression, and resistance against cancer therapies, the lysosome is proposed as an attractive therapeutic target for cancer treatment. Based on the recent advances, the current review provides a comprehensive understanding of molecular mechanisms of lysosome homeostasis under 3R responses: Repair, Removal (lysophagy) and Regeneration of lysosomes. These arms of 3R responses have distinct role in lysosome homeostasis although their interdependency along with switching between the pathways still remain elusive. Recent advances underpinning the crucial role of (1) ESCRT complex dependent/independent repair of lysosome, (2) various Galectins-based sensing and ubiquitination in lysophagy and (3) TFEB/TFE proteins in lysosome regeneration/biogenesis of lysosome are outlined. Later, we also emphasised how these recent advancements may aid in development of phytochemicals and pharmacological agents for targeting lysosomes for efficient cancer therapy. Some of these lysosome targeting agents, which are now at various stages of clinical trials and patents, are also highlighted in this review.

Micronuclei and Cancer

Chromosome-containing micronuclei are a feature of human cancer. Micronuclei arise from chromosome mis-segregation and characterize tumors with elevated rates of chromosomal instability. Although their association with cancer has been long recognized, only recently have we broadened our understanding of the mechanisms that govern micronuclei formation and their role in tumor progression. In this review, we provide a brief historical account of micronuclei, depict the mechanisms underpinning their creation, and illuminate their capacity to propel tumor evolution through genetic, epigenetic, and transcriptional transformations. We also posit the prospect of leveraging micronuclei as biomarkers and therapeutic targets in chromosomally unstable cancers.

SIGNIFICANCE

Micronuclei in chromosomally unstable cancer cells serve as pivotal catalysts for cancer progression, instigating transformative genomic, epigenetic, and transcriptional alterations. This comprehensive review not only synthesizes our present comprehension but also outlines a framework for translating this knowledge into pioneering biomarkers and therapeutics, thereby illuminating novel paths for personalized cancer management.

The ESCRT protein CHMP5 promotes T cell leukemia by controlling BRD4-p300-dependent transcription

Oncogene activity rewires cellular transcription, creating new transcription networks to which cancer cells become addicted, by mechanisms that are still poorly understood. Using human and mouse models of T cell acute lymphoblastic leukemia (T-ALL), we identify an essential nuclear role for CHMP5, a cytoplasmic endosomal sorting complex required for transport (ESCRT) protein, in establishing and maintaining the T-ALL transcriptional program. Nuclear CHMP5 promoted the T-ALL gene program by augmenting recruitment of the co-activator BRD4 by the histone acetyl transferase p300 selectively at enhancers and super-enhancers, an interaction that potentiated H3K27 acetylation at these regulatory enhancers. Consequently, loss of CHMP5 diminished BRD4 occupancy at enhancers and super-enhancers and impaired RNA polymerase II pause release, which resulted in downregulation of key T-ALL genes, notably MYC. Reinforcing its importance in T-ALL pathogenesis, CHMP5 deficiency mitigated chemoresistance in human T-ALL cells and abrogated T-ALL induction by oncogenic NOTCH1 in vivo. Thus, the ESCRT protein CHMP5 is an essential positive regulator of the transcriptional machinery promoting T-ALL disease.

Multiomics characterization of pyroptosis in the tumor microenvironment and therapeutic relevance in metastatic melanoma

BACKGROUND

Pyroptosis, mediated by gasdermins with the release of multiple inflammatory cytokines, has emerged as playing an important role in targeted therapy and immunotherapy due to its effectiveness at inhibiting tumor growth. Melanoma is one of the most commonly used models for immunotherapy development, though an inadequate immune response can occur. Moreover, the development of pyroptosis-related therapy and combinations with other therapeutic strategies is limited due to insufficient understanding of the role of pyroptosis in the context of different tumor immune microenvironments (TMEs).

METHODS

Here, we present a computational model (pyroptosis-related gene score, PScore) to assess the pyroptosis status. We applied PScore to 1388 melanoma samples in our in-house cohort and eight other publicly available independent cohorts and then calculated its prognostic power of and potential as a predictive marker of immunotherapy efficacy. Furthermore, we performed association analysis for PScore and the characteristics of the TME by using bulk, single-cell, and spatial transcriptomics and assessed the association of PScore with mutation status, which contributes to targeted therapy.

RESULTS

Pyroptosis-related genes (PRGs) showed distinct expression patterns and prognostic predictive ability in melanoma. Most PRGs were associated with better survival in metastatic melanoma. Our PScore model based on genes associated with prognosis exhibits robust performance in survival prediction in multiple metastatic melanoma cohorts. We also found PScore to be associated with BRAF mutation and correlate positively with multiple molecular signatures, such as KRAS signaling and the IFN gamma response pathway. Based on our data, melanoma with an immune-enriched TME had a higher PScore than melanoma with an immune-depleted or fibrotic TME. Additionally, monocytes had the highest PScore and malignant cells and fibroblasts the lowest PScore based on single-cell and spatial transcriptome analyses. Finally, a higher PScore was associated with better therapeutic efficacy of immune checkpoint blockade, suggesting the potential of pyroptosis to serve as a marker of immunotherapy response.

CONCLUSIONS

Collectively, our findings indicate that pyroptosis is a prognostic factor and is associated with the immune response in metastatic melanoma, as based on multiomics data. Our results provide a theoretical basis for drug combination and reveal potential immunotherapy response markers.

TXNDC12 inhibits lipid peroxidation and ferroptosis

Ferroptosis is a type of regulated cell death characterized by lipid peroxidation and subsequent damage to the plasma membrane. Here, we report a ferroptosis resistance mechanism involving the upregulation of TXNDC12, a thioredoxin domain-containing protein located in the endoplasmic reticulum. The inducible expression of TXNDC12 during ferroptosis in leukemia cells is inhibited by the knockdown of the transcription factor ATF4, rather than NFE2L2. Mechanistically, TXNDC12 acts to inhibit lipid peroxidation without affecting iron accumulation during ferroptosis. When TXNDC12 is overexpressed, it restores the sensitivity of ATF4-knockdown cells to ferroptosis. Moreover, TXNDC12 plays a GPX4-independent role in inhibiting lipid peroxidation. The absence of TXNDC12 enhances the tumor-suppressive effects of ferroptosis induction in both cell culture and animal models. Collectively, these findings demonstrate an endoplasmic reticulum-based anti-ferroptosis pathway in cancer cells with potential translational applications.

Pyroptosis-related gene signature: A predictor for overall survival, immunotherapy response, and chemosensitivity in patients with pancreatic adenocarcinoma

Background

Pancreatic adenocarcinoma (PAAD) is a lethal malignancy with high levels of heterogeneity. Pyroptosis is thought to influence the development of various tumors. Nevertheless, the role of pyroptosis-related genes (PRGs) in prognostic risk stratification and therapeutic guidance for PAAD remains ambiguously.

Methods

Transcriptome profile and clinical information of PAAD patients were retrieved from The Cancer Genome Atlas (TCGA) as well as Gene Expression Omnibus (GEO) databases, followed by differential analysis. Patients were divided into distinct pyroptosis phenotype subtypes based on the characteristic of differently expressed PRGs (DEPRGs). Then a PRG signature was established through univariate analysis and LASSO algorithm in the training set to assess the prognostic risk, and its reliability was verified in the validation set using receiver operating characteristic(ROC) curve. The correlation of risk score with tumor microenvironment(TME), TMB and chemotherapeutic drug sensitivity were also analyzed. In addition, a nomogram was constructed to promote better clinical application.

Results

A total of 28 DEPRGs were determined in the integrated TCGA-GEO datasets. Patients were divided into three pyroptosis phenotype subtypes, Kaplan-Meier curve suggested patients in cluster B had a worse prognosis than those in cluster A and C. Then a price signature comprised of 8 PRGs was generated. TME analysis suggested that the low-risk subgroup displayed potential stronger antitumor immune effect and might respond better to immune checkpoint inhibitors (ICIs) therapy. Furthermore, PRG signature exhibited favorable discriminatory ability for TMB status and the sensitivity of multiple conventional chemotherapeutic agents including paclitaxel. Ultimately, we constructed a promising nomogram according to the risk score and N stage with good predictive accuracy compared with the actual overall survival (OS) probabilities.

Conclusion

We established an 8-gene signature that could be regarded as an independent prognostic risk factor for PAAD patients. The 8-gene signature could provide rationale for immunotherapy and chemotherapy, which might help clinicians make precise individualized treatment regimens.

Selective cargo sorting in stem cell-derived small extracellular vesicles: impact on therapeutic efficacy for intervertebral disc degeneration

BACKGROUND

Growing evidence has suggested the role of stem cell-derived small extracellular vesicles (sEVs) in intervertebral disc degeneration (IVDD). The cargo sorting of sEVs, particularly miRNAs, may be influenced when the donor cell is subjected to oxidative stress. Here, we discovered that miRNAs containing specific motifs are selectively sorted into intraluminal vesicles within mesenchymal stem cells (MSCs) in response to oxidative stress.

METHODS

Analysis of miRNA cargoes in sEVs derived from normal MSCs (C-sEVs) or stressed MSCs (T-sEVs) was conducted using miRNA sequencing. Differential expressed miRNAs in sEVs and the identification of motifs were evaluated through bioinformatics analysis. Protein binding was assessed using immunofluorescent staining and immunoprecipitation analysis. Additionally, RNA pull down and RNA immunoprecipitation (RIP) immunoprecipitation were employed to determine the binding between miRNAs and proteins. The effects of C-sEVs and T-sEVs on IVDD were compared by detecting the expression levels of phenotypic genes in vitro or histological evaluation in vivo.

RESULTS

The sorting process of miRNAs is mediated by the nucleocytoplasmic transport of heterogeneous nuclear ribonucleoproteins, which in turn facilitates the phosphorylation of SNAP25 and promotes the transport and secretion of sEVs. Additionally, CHMP1B plays a role in membrane repair and protects against cell ferroptosis upon oxidative stress, concurrently affecting the release of sEVs. Notably, stem cell-derived sEVs associated with ferroptosis impair the therapeutic efficacy for IVDD. However, the application of engineered sEVs containing a specific miRNA inhibitor exhibits the potential to reinstate the therapeutic efficacy for IVDD both in vitro and in vivo.

CONCLUSIONS

Taken together, our findings shed light on the mechanism of miRNAs sorting into sEVs and offer new insights for the optimization of sEV-based treatments during intervertebral disc regeneration. regeneration.

CORM‑2 reduces cisplatin accumulation in the mouse inner ear and protects against cisplatin-induced ototoxicity

INTRODUCTION

Cisplatin is a life-saving anticancer compound used to treat multiple solid malignant tumors, while it causes permanent hearing loss. There is no known cure, and the FDA has not approved any preventative treatment for cisplatin-based ototoxicity.

OBJECTIVES

This study investigated whether the carbon monoxide (CO)-releasing tricarbonyldichlororuthenium (II) dimer, CORM-2, reverses cisplatin-induced hearing impairment and reduces cisplatin accumulation in the mouse inner ear.

METHODS

Male 6-week-old BALB/c mice were randomly assigned to one of the following groups: control (saline-treated, i.p.), CORM-2 only (30 mg/kg, i.p., four doses), cisplatin only (20 mg/kg, i.p., one dose), and CORM-2 + cisplatin, to determine whether cisplatin-based hearing impairment was alleviated by CORM-2 treatment.

RESULTS

Our results revealed CORM-2 significantly attenuated cisplatin-induced hearing loss in young adult mice. CORM-2 co-treatment significantly decreased platinum accumulation in the inner ear and activated the plasma membrane repair system of the stria vascularis. Moreover, CORM-2 co-treatment significantly decreased cisplatin-induced inflammation, apoptosis, and cochlear necroptosis. Because the stria vascularis is the likely cochlear entry point of cisplatin, we next focused on the microvasculature. Cisplatin induced increased extravasation of a chromatic tracer (fluorescein isothiocyanate [FITC]-dextran, MW 75 kDa) around the cochlear microvessels at 4 days post-treatment; this extravasation was completely inhibited by CORM-2 co-therapy. CORM-2 co-treatment effectively maintained the integrity of stria vascularis components including endothelial cells, pericytes, and perivascular-resident macrophage-type melanocytes.

CONCLUSION

CORM-2 co-therapy substantially protects against cisplatin-induced ototoxicity by reducing platinum accumulation and toxic cellular stress responses. These data indicate that CORM-2 co-treatment may be translated into clinical strategy to reduce cisplatin-induced hearing loss.

Cell organelles are retained inside pyroptotic corpses during inflammatory cell death

Many proinflammatory proteins are released via the necrotic form of cell death known as pyroptosis. Sometimes known as gasdermin D (GSDMD) dependent cell death, pyroptosis results from the formation of pores in the plasma membrane leading to eventual cell lysis. Seeking to understand the magnitude of this cell lysis we measured the size of proteins released during pyroptosis. We demonstrate that there is no restriction on the size of soluble proteins released during pyroptosis even at early timepoints. However, even though large molecules can exit the dying cell, organelles are retained within it. This observation indicates that complete cell rupture may not be a consequence of pyroptosis, and that plasma membrane architecture is retained.

Endoplasmic Reticulum-Targeted Aggregation-Induced Emission Luminogen for Synergetic Tumor Ablation with Glibenclamide

Photodynamic therapy based on fluorescence illumination of subcellular organelles and in situ bursts of reactive oxygen species (ROS) has been recognized as a promising strategy for cancer theranostics. However, the short life of ROS and unclarified anticancer mechanism seriously restrict the application. Herein, we rationally designed and facilely synthesized a 2,6-dimethylpyridine-based triphenylamine (TPA) derivative TPA-DMPy with aggregation-induced emission (AIE) features and production of type-I ROS. Except for its selective binding to the endoplasmic reticulum (ER), TPA-DMPy, in synergy with glibenclamide, a medicinal agent used against diabetes, induced significant apoptosis of cancer cells in vitro and in vivo. Additionally, TPA-DMPy greatly incited the release of calcium from ER upon light irradiation to further aggravate the depolarization of ER membrane potential caused by glibenclamide, thus inducing fatal ER stress and crosstalk between ER and mitochondria. Our study extends the biological design and application of AIE luminogens and provides new insights into discovering novel anticancer targets and agents.

FSP1: a key regulator of ferroptosis

Ferroptosis suppressor protein 1 (FSP1) is one of the main regulatory molecules of ferroptosis. FSP1 functions through the FSP1-coenzyme Q10 (CoQ10)-NAD(P)H axis and the vitamin K redox cycle. FSP1 is regulated by upstream factors, including transcription factors and noncoding RNA (ncRNA), and is subject to epigenetic modifications, which affect the progress of FSP1-related diseases. FSP1 is closely associated with the poor prognosis of malignant tumors and plays an important role in disease treatment. This review aims to provide a comprehensive understanding of the role of FSP1 in ferroptosis regulation by summarizing regulatory pathways, possible mechanisms involving FSP1, and the relationship between FSP1 and disease prognosis and treatment.

Platelet-derived extracellular vesicles for drug delivery

Platelet-derived extracellular vesicles (PEVs) are a subset of EVs that are released from platelets, which are small nuclear cell fragments that play a critical role in hemostasis and thrombosis. PEVs have been shown to have important roles in a variety of physiological and pathological processes, including inflammation, angiogenesis, and cancer. Recently, researchers, including our group have utilized PEVs as drug delivery platforms as PEVs could target inflammatory sites both passively and actively. This review summarizes the biological function of PEVs, introduces recent applications of PEVs in targeted drug delivery, and provides an outlook for the further development of utilizing PEVs for drug delivery.

UHRF1 is a mediator of KRAS driven oncogenesis in lung adenocarcinoma

KRAS is a frequent driver in lung cancer. To identify KRAS-specific vulnerabilities in lung cancer, we performed RNAi screens in primary spheroids derived from a Kras mutant mouse lung cancer model and discovered an epigenetic regulator Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1). In human lung cancer models UHRF1 knock-out selectively impaired growth and induced apoptosis only in KRAS mutant cells. Genome-wide methylation and gene expression analysis of UHRF1-depleted KRAS mutant cells revealed global DNA hypomethylation leading to upregulation of tumor suppressor genes (TSGs). A focused CRISPR/Cas9 screen validated several of these TSGs as mediators of UHRF1-driven tumorigenesis. In vivo, UHRF1 knock-out inhibited tumor growth of KRAS-driven mouse lung cancer models. Finally, in lung cancer patients high UHRF1 expression is anti-correlated with TSG expression and predicts worse outcomes for patients with KRAS mutant tumors. These results nominate UHRF1 as a KRAS-specific vulnerability and potential target for therapeutic intervention.

Ferroptosis: From regulation of lipid peroxidation to the treatment of diseases

Ferroptosis is a regulated cell death mainly manifested by iron-dependent lipid peroxide accumulation. The leading cause of ferroptosis is the imbalance of intracellular oxidative systems (e.g., LOXs, POR, ROS) and antioxidant systems (e.g., GSH/GPx4, CoQ10/FSP1, BH4/GCH1), which is regulated by a complex network. In the past decade, this metabolic network has been continuously refined, and the links with various pathophysiological processes have been gradually established. Apoptosis has been regarded as the only form of regulated cell death for a long time, and the application of chemotherapeutic drugs to induce apoptosis of cancer cells is the mainstream method. However, studies have reported that cancer cells' key features are resistance to apoptosis and chemotherapeutics. For high proliferation, cancer cells often have very active lipid metabolism and iron metabolism, which pave the way for ferroptosis. Interestingly, researchers found that drug-resistant or highly aggressive cancer cells are more prone to ferroptosis. Therefore, ferroptosis may be a potential strategy to eliminate cancer cells. In addition, links between ferroptosis and other diseases, such as neurological disorders and ischemia-reperfusion injury, have also been found. Understanding these diseases from the perspective of ferroptosis may provide new insights into clinical treatment. Herein, the metabolic processes in ferroptosis are reviewed, and the potential mechanisms and targets of ferroptosis in different diseases are summarized.

Dark repair of sunlight-inactivated tetracycline-resistant bacteria: Mechanisms and important role of bacteria in viable but non-culturable state

The spread of antibiotic resistant bacteria (ARB) in the environment poses a potential threat to human health, and the reactivation of inactivated ARB accelerated the spread of ARB. However, little is known about the reactivation of sunlight-inactivated ARB in natural waters. In this study, the reactivation of sunlight-inactivated ARB in dark conditions was investigated with tetracycline-resistant E. coli (Tc-AR E. coli) as a representative. Results showed that sunlight-inactivated Tc-AR E. coli underwent dark repair to regain tetracycline resistance with dark repair ratios increasing from (0.124 ± 0.012)‱ within 24 h dark treatment to (0.891 ± 0.033)‱ within 48 h. The presence of Suwannee River fulvic acid (SRFA) promoted the reactivation of sunlight-inactivated Tc-AR E. coli and tetracycline inhibited their reactivation. The reactivation of sunlight-inactivated Tc-AR E. coli is mainly attributed to the repair of the tetracycline-specific efflux pump in the cell membrane. Tc-AR E. coli in a viable but non-culturable (VBNC) state was observed and dominated the reactivation as the inactivated ARB remain present in the dark for more than 20 h. These results explained the reason for distribution difference of Tc-ARB at different depths in natural waters, which are of great significance for understanding the environmental behavior of ARB.

4D Force Detection of Cell Adhesion and Contractility

Mechanical signals establish two-way communication between mammalian cells and their environment. Cells contacting a surface exert forces via contractility and transmit them at the areas of focal adhesions. External stimuli, such as compressive and pulling forces, typically affect the adhesion-free cell surface. Here, we demonstrate the collaborative employment of Fluidic Force Microscopy and confocal Traction Force Microscopy supported by the Cellogram solver to enable a powerful integrated force probing approach, where controlled vertical forces are applied to the free surface of individual cells, while the concomitant deformations are used to map their transmission to the substrate. Force transmission across human cells is measured with unprecedented temporal and spatial resolution, enabling the investigation of the cellular mechanisms involved in the adaptation, or maladaptation, to external mechanical stimuli. Altogether, the system enables facile and precise force interrogation of individual cells, with the capacity to perform population-based analysis.

Ferroptosis in hepatocellular carcinoma: from bench to bedside

The most widespread type of liver cancer, HCC, is associated with disabled cellular death pathways. Despite therapeutic advancements, resistance to current systemic treatments (including sorafenib) compromises the prognosis of patients with HCC, driving the search for agents that might target novel cell death pathways. Ferroptosis, a form of iron-mediated nonapoptotic cell death, has gained considerable attention as a potential target for cancer therapy, especially in HCC. The role of ferroptosis in HCC is complex and diverse. On one hand, ferroptosis can contribute to the progression of HCC through its involvement in both acute and chronic liver conditions. In contrast, having ferroptosis affect HCC cells might be desirable. This review examines the role of ferroptosis in HCC from cellular, animal, and human perspectives while examining its mechanisms, regulation, biomarkers, and clinical implications.

Membrane Integrity Assay in Ferroptosis

Ferroptosis is a form of regulated cell death that relies on the accumulation of intracellular iron and subsequent oxidative stress. Ferroptotic cell death is characterized by uncontrolled lipid peroxidation, which leads to plasma membrane damage and rupture. The loss of plasma membrane integrity results in the release of intracellular components, including damage-associated molecular patterns, and can propagate death between cells in a synchronized manner. Understanding the mechanisms of ferroptotic membrane damage is crucial to comprehending this form of cell death. This chapter provides a summary of techniques for detecting plasma membrane integrity in ferroptosis, including transmission electron microscopy analysis, flow cytometry analysis, and assessments of oxidoreductase-mediated membrane damage.

Resolution Potential of Necrotic Cell Death Pathways

During tissue damage caused by infection or sterile inflammation, not only damage-associated molecular patterns (DAMPs), but also resolution-associated molecular patterns (RAMPs) can be activated. These dying cell-associated factors stimulate immune cells localized in the tissue environment and induce the production of inflammatory mediators or specialized proresolving mediators (SPMs). Within the current prospect of science, apoptotic cell death is considered the main initiator of resolution. However, more RAMPs are likely to be released during necrotic cell death than during apoptosis, similar to what has been observed for DAMPs. The inflammatory potential of many regulated forms of necrotic cell death modalities, such as pyroptosis, necroptosis, ferroptosis, netosis, and parthanatos, have been widely studied in necroinflammation, but their possible role in resolution is less considered. In this review, we aim to summarize the relationship between necrotic cell death and resolution, as well as present the current available data regarding the involvement of certain forms of regulated necrotic cell death in necroresolution.

A Novel Defined Pyroptosis-Related Gene Signature for the Prognosis of Acute Myeloid Leukemia

Pyroptosis is an inflammatory form of programmed necrotic cell death, but its potential prognostic value in acute myeloid leukemia (AML) remains unclear. On the basis of available AML data from TCGA and TARGET databases, a 10-gene signature model was constructed to effectively predict AML prognosis by performing LASSO Cox regression analysis, which showed that patients with a low-risk score had a significantly better prognosis than that of the high-risk group, and receiver operator characteristic (ROC) analysis achieved superior performance in the prognostic model. The model was further well-verified in an external GEO cohort. Multivariable Cox regression analysis showed that, in addition to age, the risk score was an independent poor survival factor for AML patients, and a nomogram model was constructed with high accuracy. Moreover, the high-risk group generally had higher cytolytic activity and increased levels of infiltrating immune cells, including tumor-infiltrating lymphocytes (TILs) and regulatory T cells (Tregs), which could be related to the expression of immune checkpoint genes. Additionally, low-risk AML patients may have a better response from traditional chemotherapeutic drugs. In conclusion, a pyroptosis-related gene signature can independently predict the prognosis of AML patients with sufficient predictive power, and pyroptosis plays an important role in the immune microenvironment of AML, which may be used to develop a new effective therapeutic method for AML in the future.

Signaling pathways and defense mechanisms of ferroptosis

As a type of lytic cell death driven by unrestricted lipid peroxidation and subsequent plasma membrane damage, ferroptosis occurs and develops because of sophisticated signals and regulatory mechanisms. The reactive oxygen species (ROS) used to initiate ferroptosis come from a variety of sources, including iron-mediated Fenton reactions, mitochondrial ROS, and membrane-associated ROS driven by the NOX protein family. Polyunsaturated fatty acid-containing phospholipids are the main substrates of lipid peroxidation in ferroptosis, which is positively regulated by enzymes, such as ACSL4, LPCAT3, ALOXs, or POR. Selective activation of autophagic degradation pathways promotes ferroptosis by increasing iron accumulation to cause lipid peroxidation. In contrast, system xc^- -glutathione-GPX4 axis plays a central role in limiting lipid peroxidation, although other antioxidants (such as coenzyme Q10 and tetrahydrobiopterin) can also inhibit ferroptosis. A main nuclear mechanism of cell defense against ferroptosis is the activation of the NFE2L2-dependent antioxidant response by transcriptionally upregulating the expression of antioxidants or cytoprotective genes. Additionally, the membrane damage caused by ferroptotic stimulus can be repaired by ESCRT-III-dependent membrane scission machinery. In this review, we summarize recent progress in understanding the signaling pathways and defense mechanisms of ferroptosis.

Molecular mechanisms and roles of pyroptosis in acute lung injury

ABSTRACT

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), which are characterized by excessive inflammation and accompanied by diffuse injury of alveoli, can result in severe respiratory failures. The morbidity and mortality of patients remain high because the major treatments for ALI/ARDS are mainly supportive due to the lack of effective therapies. Numerous studies have demonstrated that the aggravation of coronavirus disease 2019 (COVID-19) leads to severe pneumonia and even ARDS. Pyroptosis, a biological process identified as a type of programed cell death, is mainly triggered by inflammatory caspase activation and is directly meditated by the gasdermin protein family, as well as being associated with the secretion and release of pro-inflammatory cytokines. Clinical and experimental evidence corroborates that pyroptosis of various cells in the lung, such as immune cells and structural cells, may play an important role in the pathogenesis of "cytokine storms" in ALI/ARDS, including those induced by COVID-19. Here, with a focus on ALI/ARDS and COVID-19, we summarized the recent advances in this field and proposed the theory of an inflammatory cascade in pyroptosis to identify new targets and pave the way for new approaches to treat these diseases.

The endosomal sorting complex required for transport repairs the membrane to delay cell death

The endosomal sorting complex required for transport (ESCRT) machinery plays a key role in the repair of damaged plasma membranes with puncta form and removes pores from the plasma membrane in regulated cell death, apoptosis, necroptosis, pyroptosis, ferroptosis, and autophagy. ESCRT-I overexpression and ESCRT-III-associated charged multivesicular body protein (CHMP) 4B participate in apoptosis, and the ESCRT-1 protein TSG 101 maintains low levels of ALIX and ALG-2 and prevents predisposition to apoptosis. The ESCRT-III components CHMP2A and CHMP4B are recruited to broken membrane bubble sites with the requirement of extracellular Ca2+, remove membrane vesicles from cells, and delay the time required for active MLKL to mediate necroptosis, thus preserving cell survival. CHMP4B disturbed pyroptosis by recruiting around the plasma membrane neck to remove the GSDMD pores and preserve plasma membrane integrity depending on Ca2+ influx. The accumulation of the ESCRT-III subunits CHMP5 and CHMP6 in the plasma membrane is increased by the classical ferroptosis activators erastin-1 and ras-selective lethal small molecule 3 (RSL3) upon cytosolic calcium influx and repairs the ferroptotic plasma membrane. ESCRT-III- and VPS4-induced macroautophagy, ESCRT-0-initiated microautophagy. ESCRT-I, ESCRT-II, ESCRT-III, ALIX, and VPS4A are recruited to damaged lysosomes and precede lysophagy, indicating that ESCRT is a potential target to overcome drug resistance during tumor therapy.

Polymyxin B Reduces Brain Injury in Ischemic Stroke Rat Through a Mechanism Involving Targeting ESCRT-III Machinery and RIPK1/RIPK3/MLKL Pathway

Endosomal sorting complex required for transport III (ESCRT-III) machinery is a key component to counteract the mixed lineage kinase domain-like pseudokinase (MLKL)-induced plasma membrane broken in cells undergoing necroptosis. Based on the bioinformatics analysis, polymyxin B, a polypeptide antibiotic, is predicted to simultaneously interact with ESCRT-III subunits and necroptosis-relevant proteins. This study aims to explore whether polymyxin B could reduce necroptosis in the stroke rat brain via enhancing the ESCRT-III machinery and/or suppressing the RIPK1/RIPK3/MLKL pathway. The stroke rats showed evident brain injury, concomitant with the downregulation of ESCRT-III subunits and the upregulation of necroptosis-relevant proteins. Post-ischemic administration of polymyxin B could alleviate the brain injury, accompanied by restoration of the levels of ESCRT-III subunits and suppression of necroptosis-relevant proteins. And, polymyxin B exerted similar effects in hypoxia-treated HT22 cells. We conclude that polymyxin B can reduce necroptosis in the stroke rat brain via enhancing the ESCRT-III machinery and suppressing the RIPK1/RIPK3/MLKL pathway simultaneously.

Identification of a prognostic index system and tumor immune infiltration characterization for lung adenocarcinoma based on mRNA molecular of pyroptosis

Background and purpose

Pyroptosis is a form of programmed cell death, which plays an important role in tumorigenesis, progression, and regulation of the tumor microenvironment. It can affect lung adenocarcinoma (LUAD) progression. This study aimed to construct a pyroptosis-related mRNA prognostic index (PRMPI) for LUAD and clarify the tumor microenvironment infiltration characterization of LUAD.

Materials and methods

We performed a univariate Cox regression analysis for pyroptosis-related mRNAs in the TCGA cohort. Then, we used LASSO Cox regression to establish a PRMPI. The quantitative real time polymerase chain reaction (qRT-PCR) was used to quantify the relative expression of pyroptosis-related mRNAs. The CPTAC cohort was used to confirm the stability and wide applicability of the PRMPI. The single-sample gene set enrichment analysis (ssGSEA) was performed to assess the tumor microenvironment infiltration characterization.

Results

A total of 36 pyroptosis-related mRNAs were identified. The PRMPI was established based on five pyroptosis-related mRNAs. The expression patterns of these mRNAs were verified in LUAD samples from our medical center by qRT-PCR. High-PRMPI patients had worse overall survival than low-PRMPI patients. The result was validated in the CPTAC cohort. The comprehensive analysis indicated that the high-PRMPI patients exhibited lower immune activity, more aggressive immunophenotype, lower expression of immune checkpoint molecule, higher TP53 mutation rate, and higher tumor stemness than low-PRMPI patients. Low-PRMPI patients may be more sensitive to immunotherapy, while high-PRMPI patients may benefit more from chemotherapy and targeted therapy.

Conclusions

The PRMPI may be a promising biomarker to predict the prognosis, tumor microenvironment infiltration characterization, and the response to adjuvant therapy in LUAD.

Pyroptosis and Its Role in the Modulation of Cancer Progression and Antitumor Immunity

Pyroptosis is a type of programmed cell death (PCD) accompanied by an inflammatory reaction and the rupture of a membrane. Pyroptosis is divided into a canonical pathway triggered by caspase-1, and a non-canonical pathway independent of caspase-1. More and more pyroptosis-related participants, pathways, and regulatory mechanisms have been exploited in recent years. Pyroptosis plays crucial roles in the initiation, progression, and metastasis of cancer and it affects the immunotherapeutic outcome by influencing immune cell infiltration as well. Extensive studies are required to elucidate the molecular mechanisms between pyroptosis and cancer. In this review, we introduce the discovery history of pyroptosis, delineate the signaling pathways of pyroptosis, and then make comparisons between pyroptosis and other types of PCD. Finally, we provide an overview of pyroptosis in different cancer types. With the progression in the field of pyroptosis, new therapeutic targets and strategies can be explored to combat cancer.

Identification of Key Pyroptosis-Related Genes and Distinct Pyroptosis-Related Clusters in Periodontitis

Aim

This study aims to identify pyroptosis-related genes (PRGs), their functional immune characteristics, and distinct pyroptosis-related clusters in periodontitis.

Methods

Differentially expressed (DE)-PRGs were determined by merging the expression profiles of GSE10334, GSE16134, and PRGs obtained from previous literatures and Molecular Signatures Database (MSigDB). Least absolute shrinkage and selection operator (LASSO) regression was applied to screen the prognostic PRGs and develop a prognostic model. Consensus clustering was applied to determine the pyroptosis-related clusters. Functional analysis and single-sample gene set enrichment analysis (ssGSEA) were performed to explore the biological characteristics and immune activities of the clusters. The hub pyroptosis-related modules were defined using weighted correlation network analysis (WGCNA).

Results

Of the 26 periodontitis-related DE-PRGs, the highest positive relevance was for High-Mobility Group Box 1 (HMGB1) and SR-Related CTD Associated Factor 11 (SCAF11). A 14-PRG-based signature was developed through the LASSO model. In addition, three pyroptosis-related clusters were obtained based on the 14 prognostic PRGs. Caspase 3 (CASP3), Granzyme B (GZMB), Interleukin 1 Alpha (IL1A), IL1Beta (B), IL6, Phospholipase C Gamma 1 (PLCG1) and PYD And CARD Domain Containing (PYCARD) were dysregulated in the three clusters. Distinct biological functions and immune activities, including human leukocyte antigen (HLA) gene expression, immune cell infiltration, and immune pathway activities, were identified in the three pyroptosis-related clusters of periodontitis. Furthermore, the pink module associated with endoplasmic stress-related functions was found to be correlated with cluster 2 and was suggested as the hub pyroptosis-related module.

Conclusion

The study identified 14 key pyroptosis-related genes, three distinct pyroptosis-related clusters, and one pyroptosis-related gene module describing several molecular aspects of pyroptosis in the pathogenesis and immune micro-environment regulation of periodontitis and also highlighted functional heterogeneity in pyroptosis-related mechanisms.

Non-coding RNAs and ferroptosis: potential implications for cancer therapy

Ferroptosis is a recently defined form of regulated cell death, which is biochemically and morphologically distinct from traditional forms of programmed cell death such as apoptosis or necrosis. It is driven by iron, reactive oxygen species, and phospholipids that are oxidatively damaged, ultimately resulting in mitochondrial damage and breakdown of membrane integrity. Numerous cellular signaling pathways and molecules are involved in the regulation of ferroptosis, including enzymes that control the cellular redox status. Alterations in the ferroptosis-regulating network can contribute to the development of various diseases, including cancer. Evidence suggests that ferroptosis is commonly suppressed in cancer cells, allowing them to survive and progress. However, cancer cells which are resistant to common chemotherapeutic drugs seem to be highly susceptible to ferroptosis inducers, highlighting the great potential of pharmacologic modulation of ferroptosis for cancer treatment. Non-coding RNAs (ncRNAs) are considered master regulators of various cellular processes, particularly in cancer where they have been implicated in all hallmarks of cancer. Recent work also demonstrated their involvement in the molecular control of ferroptosis. Hence, ncRNA-based therapeutics represent an exciting alternative to modulate ferroptosis for cancer therapy. This review summarizes the ncRNAs implicated in the regulation of ferroptosis in cancer and highlights their underlying molecular mechanisms in the light of potential therapeutic applications.

HRAS Q61L Mutation as a Possible Target for Non-Small Cell Lung Cancer: Case Series and Review of Literature

Introduction: Assessment of actionable gene mutations and oncogene fusions have made a paradigm shift in treatment strategies of non-small cell lung cancer (NSCLC). HRAS mutations involved around 0.2–0.8% of NSCLC patients, mostly on codon 61. For these patients, few data are available regarding clinical characteristics and response to therapies. Methods: Next-Generation Sequencing (NGS) done routinely at Nantes University Hospital was used to identify HRAS molecular alterations in NSCLC patients. We identified and described four HRAS p.GlnQ61Leu mutated patients. Literature of previously HRAS-mutant NSCLC cases was reviewed, and available data in solid tumour with the most advanced H-Ras specific inhibitor, tipifarnib, were presented. Results: Of 1614 patients diagnosed with advanced NSCLC from January 2018 to December 2020, four (0.25%) had HRAS p.Gln61Leu mutation. Three of them died during the first-line systemic therapy. Furthermore, three additional cases were identified in literature. All cases were current or former smokers, most of them had pleural or pericardial effusion at diagnosis. Conclusions: The clinical course of patients with HRAS-mutant NSCLC remains unclear. Furthers cases should be identified in order to clarify prognosis and response to therapies. Tipifarnib, a farnesyl transferase inhibitor, is a promising candidate to target HRAS-mutant tumours and should be explored in NSCLC patients.

CHMP2A regulates tumor sensitivity to natural killer cell-mediated cytotoxicity

Natural killer (NK) cells are known to mediate killing of various cancer types, but tumor cells can develop resistance mechanisms to escape NK cell-mediated killing. Here, we use a "two cell type" whole genome CRISPR-Cas9 screening system to discover key regulators of tumor sensitivity and resistance to NK cell-mediated cytotoxicity in human glioblastoma stem cells (GSC). We identify CHMP2A as a regulator of GSC resistance to NK cell-mediated cytotoxicity and we confirm these findings in a head and neck squamous cells carcinoma (HNSCC) model. We show that deletion of CHMP2A activates NF-κB in tumor cells to mediate increased chemokine secretion that promotes NK cell migration towards tumor cells. In the HNSCC model we demonstrate that CHMP2A mediates tumor resistance to NK cells via secretion of extracellular vesicles (EVs) that express MICA/B and TRAIL. These secreted ligands induce apoptosis of NK cells to inhibit their antitumor activity. To confirm these in vitro studies, we demonstrate that deletion of CHMP2A in CAL27 HNSCC cells leads to increased NK cell-mediated killing in a xenograft immunodeficient mouse model. These findings illustrate a mechanism of tumor immune escape through EVs secretion and identify inhibition of CHMP2A and related targets as opportunities to improve NK cell-mediated immunotherapy.

A Pleiotropic Role of Long Non-Coding RNAs in the Modulation of Wnt/β-Catenin and PI3K/Akt/mTOR Signaling Pathways in Esophageal Squamous Cell Carcinoma: Implication in Chemotherapeutic Drug Response

Despite the availability of modern techniques for the treatment of esophageal squamous cell carcinoma (ESCC), tumor recurrence and metastasis are significant challenges in clinical management. Thus, ESCC possesses a poor prognosis and low five-year overall survival rate. Notably, the origin and recurrence of the cancer phenotype are under the control of complex cancer-related signaling pathways. In this review, we provide comprehensive knowledge about long non-coding RNAs (lncRNAs) related to Wnt/β-catenin and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway in ESCC and its implications in hindering the efficacy of chemotherapeutic drugs. We observed that a pool of lncRNAs, such as HERES, TUG1, and UCA1, associated with ESCC, directly or indirectly targets various molecules of the Wnt/β-catenin pathway and facilitates the manifestation of multiple cancer phenotypes, including proliferation, metastasis, relapse, and resistance to anticancer treatment. Additionally, several lncRNAs, such as HCP5 and PTCSC1, modulate PI3K/Akt/mTOR pathways during the ESCC pathogenesis. Furthermore, a few lncRNAs, such as AFAP1-AS1 and LINC01014, block the efficiency of chemotherapeutic drugs, including cisplatin, 5-fluorouracil, paclitaxel, and gefitinib, used for ESCC treatment. Therefore, this review may help in designing a better therapeutic strategy for ESCC patients.

Treatment effect of DNA framework nucleic acids on diffuse microvascular endothelial cell injury after subarachnoid hemorrhage

Objectives

The purpose of this study was to investigate the treatment effect and molecular mechanism of tetrahedral framework nucleic acids (tFNAs), novel self‐assembled nucleic acid nanomaterials, in diffuse BMEC injury after SAH.

Materials and Methods

tFNAs were synthesized from four ssDNAs. The effects of tFNAs on SAH‐induced diffuse BMEC injury were explored by a cytotoxicity model induced by hemin, a breakdown product of hemoglobin, in vitro and a mouse model of SAH via internal carotid artery puncture in vivo. Cell viability assays, wound healing assays, transwell assays, and tube formation assays were performed to explore cellular function like angiogenesis.

Results

In vitro cellular function assays demonstrated that tFNAs could alleviate hemin‐induced injury, promote angiogenesis, and inhibit apoptosis in hemin cytotoxicity model. In vivo study using H&E and TEM results jointly indicated that the tFNAs attenuate the damage caused by SAH in situ, showing restored number of BMECs in the endothelium layer and more tight intercellular connectivity. Histological examination of SAH model animals confirmed the results of the in vitro study, as tFNAs exhibited treatment effects against diffuse BMEC injury in the cerebral microvascular bed.

Conclusions

Our study suggests the potential of tFNAs in ameliorating diffuse injury to BMECs after SAH, which laid theoretical foundation for the further study and use of these nucleic acid nanomaterials for tissue engineering vascularization.

Glutamine-Derived Aspartate Biosynthesis in Cancer Cells: Role of Mitochondrial Transporters and New Therapeutic Perspectives

Simple Summary

In recent years, aspartate has been increasingly acknowledged as a critical player in the metabolism of cancer cells which use this metabolite for nucleotide and protein synthesis and for redox homeostasis. Most intracellular aspartate derives from the mitochondrial catabolism of glutamine. To date at least four mitochondrial transporters have been involved in this metabolic pathway. Their involvement appears to be cancer type-specific and dependent on glutamine availability. Targeting these mitochondrial transporters may represent a new attractive strategy to fight cancer. The aim of this review is to dissect the role of each of these transporters in relation to the type of cancer and the availability of nutrients in the tumoral microenvironment.

Abstract

Aspartate has a central role in cancer cell metabolism. Aspartate cytosolic availability is crucial for protein and nucleotide biosynthesis as well as for redox homeostasis. Since tumor cells display poor aspartate uptake from the external environment, most of the cellular pool of aspartate derives from mitochondrial catabolism of glutamine. At least four transporters are involved in this metabolic pathway: the glutamine (SLC1A5_var), the aspartate/glutamate (AGC), the aspartate/phosphate (uncoupling protein 2, UCP2), and the glutamate (GC) carriers, the last three belonging to the mitochondrial carrier family (MCF). The loss of one of these transporters causes a paucity of cytosolic aspartate and an arrest of cell proliferation in many different cancer types. The aim of this review is to clarify why different cancers have varying dependencies on metabolite transporters to support cytosolic glutamine-derived aspartate availability. Dissecting the precise metabolic routes that glutamine undergoes in specific tumor types is of upmost importance as it promises to unveil the best metabolic target for therapeutic intervention.

Heterogeneous multi-compartmental DNA hydrogel particles prepared via microfluidic assembly for lymphocyte-inspired precision medicine

Lymphocytes play a vital role in immunosurveillance through sensing biomolecules and eliminating targeted invaders. Compared with conventional therapies that depend on drug loading, lymphocytes are advantageous as they are able to ensure self-regulated therapeutics. Here, novel multi-compartmental DNA hydrogel particles were synthesized using a microfluidic assembly for intelligent cancer treatment via the logic-based control of siRNA release without external stimulation. The sensing sequence (D1) was compartmentalized from the treatment sequence (D2) with the use of core-shell DNA hydrogel particles. When D1 detects a cancer-associated biomarker, miRNA-21, a sequence cascade is triggered to release siRNA from D2, effectively eliminating the targeted cancer cells via lymphocyte-inspired precision medicine.

Shooting at Moving and Hidden Targets-Tumour Cell Plasticity and the Notch Signalling Pathway in Head and Neck Squamous Cell Carcinomas

Head and Neck Squamous Cell Carcinoma (HNSCC) is often aggressive, with poor response to current therapies in approximately 40-50% of the patients. Current therapies are restricted to operation and irradiation, often combined with a small number of standard-of-care chemotherapeutic drugs, preferentially for advanced tumour patients. Only very recently, newer targeted therapies have entered the clinics, including Cetuximab, which targets the EGF receptor (EGFR), and several immune checkpoint inhibitors targeting the immune receptor PD-1 and its ligand PD-L1. HNSCC tumour tissues are characterized by a high degree of intra-tumour heterogeneity (ITH), and non-genetic alterations that may affect both non-transformed cells, such as cancer-associated fibroblasts (CAFs), and transformed carcinoma cells. This very high degree of heterogeneity likely contributes to acquired drug resistance, tumour dormancy, relapse, and distant or lymph node metastasis. ITH, in turn, is likely promoted by pronounced tumour cell plasticity, which manifests in highly dynamic and reversible phenomena such as of partial or hybrid forms of epithelial-to-mesenchymal transition (EMT), and enhanced tumour stemness. Stemness and tumour cell plasticity are strongly promoted by Notch signalling, which remains poorly understood especially in HNSCC. Here, we aim to elucidate how Notch signal may act both as a tumour suppressor and proto-oncogenic, probably during different stages of tumour cell initiation and progression. Notch signalling also interacts with numerous other signalling pathways, that may also have a decisive impact on tumour cell plasticity, acquired radio/chemoresistance, and metastatic progression of HNSCC. We outline the current stage of research related to Notch signalling, and how this pathway may be intricately interconnected with other, druggable targets and signalling mechanisms in HNSCC.

Deliver on Time or Pay the Fine: Scheduling in Membrane Trafficking

Membrane trafficking is all about time. Automation in such a biological process is crucial to ensure management and delivery of cellular cargoes with spatiotemporal precision. Shared molecular regulators and differential engagement of trafficking components improve robustness of molecular sorting. Sequential recruitment of low affinity protein complexes ensures directionality of the process and, concomitantly, serves as a kinetic proofreading mechanism to discriminate cargoes from the whole endocytosed material. This strategy helps cells to minimize losses and operating errors in membrane trafficking, thereby matching the appealed deadline. Here, we summarize the molecular pathways of molecular sorting, focusing on their timing and efficacy. We also highlight experimental procedures and genetic approaches to robustly probe these pathways, in order to guide mechanistic studies at the interface between biochemistry and quantitative biology.

Organelle-specific regulation of ferroptosis

Ferroptosis, a cell death modality characterized by iron-dependent lipid peroxidation, is involved in the development of multiple pathological conditions, including ischemic tissue damage, infection, neurodegeneration, and cancer. The cellular machinery responsible for the execution of ferroptosis integrates multiple pro-survival or pro-death signals from subcellular organelles and then 'decides' whether to engage the lethal process or not. Here, we outline the evidence implicating different organelles (including mitochondria, lysosomes, endoplasmic reticulum, lipid droplets, peroxisomes, Golgi apparatus, and nucleus) in the ignition or avoidance of ferroptosis, while emphasizing their potential relevance for human disease and their targetability for pharmacological interventions.

SMG9 drives ferroptosis by directly inhibiting GPX4 degradation

Nonsense-mediated mRNA decay (NMD) is a quality control mechanism that plays an integral role in eliminating abnormal mRNA and corresponding proteins. It is unclear whether the NMD pathway is involved in regulating ferroptosis, which is a type of iron-dependent cell death mainly caused by the inhibition of the antioxidant SLC7A11-GPX4 axis. In this study, we conducted a small-scale RNAi screen and proved that SMG9, a component of the NMD machinery, is a selective driver for ferroptosis in human cancer cells. SMG9 positively regulates ferroptosis independent of its activity in NMD. Instead, SMG9 is a direct binding protein of GPX4 to promote the degradation of GPX4 in response to RSL3 (a GPX4 inhibitor), but not erastin (a SLC7A11 inhibitor). The genetic inhibition of SMG9 increases the accumulation of GPX4 in the mitochondria, thereby preventing mitochondrial oxidative damage, and ultimately favoring ferroptosis resistance in vitro or in xenograft mouse models. Overall, these findings establish a new mitochondrial regulation mechanism that can affect ferroptosis-mediated tumor suppression.

Inflammasome Signaling: A Novel Paradigm of Hub Platform in Innate Immunity for Cancer Immunology and Immunotherapy

Inflammasomes are fundamental innate immune mechanisms that promote inflammation and induce an inflammatory form of programmed cell death, pyroptosis. Pyroptotic inflammasome has been reported to be closely associated with tumorigenesis and prognosis of multiple cancers. Emerging studies show that the inflammasome assembly into a higher-order supramolecular complex has been utilized to evaluate the status of the innate immune response. The inflammasomes are now regarded as cellular signaling hubs of the innate immunity that drive the production of inflammatory cytokines and consequent recruitment of immune cells to the tumor sites. Herein, we provided an overview of molecular characteristics and biological properties of canonical and non-canonical inflammasome signaling in cancer immunology and immunotherapy. We also focus on the mechanism of regulating pyroptotic inflammasome in tumor cells, as well as the potential roles of inflammasome-mediated pyroptotic cell death in cancers, to explore the potential diagnostic and therapeutic markers contributing to the prevention and treatment of cancers.

miRNAs as Biomarkers for Diagnosing and Predicting Survival of Head and Neck Squamous Cell Carcinoma Patients

Simple Summary

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide. It arises from the epithelium of the upper aerodigestive tract. Increasing evidence suggests that there is a significant role of microRNAs in HNSCC formation and progression. The aim of this study was to explore and compare the expression of HNSCC related miRNAs in tumor vs neighboring healthy tissue of HNSCC patients with tumors located in either the oral cavity, oropharynx, or larynx. Our results demonstrated that expression of these miRNAs was significantly different not only between healthy and tumor tissues, but also among tumor locations. Further analysis indicated that microRNA expression could be used to distinguish between tumor and healthy tissues, and prognose the overall survival of patients.

Abstract

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide. These tumors originate from epithelial cells of the upper aerodigestive tract. HNSCC tumors in different regions can have significantly different molecular characteristics. While many microRNAs (miRNAs) have been found to be involved in the regulation of the carcinogenesis and pathogenesis of HNSCC, new HNSCC related miRNAs are still being discovered. The aim of this study was to explore potential miRNA biomarkers that can be used to diagnose HNSCC and prognose survival of HNSCC patients. For this purpose, we chose a panel of 12 miRNAs: miR-146a-5p, miR-449a, miR-126-5p, miR-34a-5p, miR-34b-5p, miR-34c-5p, miR-217-5p, miR-378c, miR-6510-3p, miR-96-5p, miR-149-5p, and miR-133a-5p. Expression of these miRNAs was measured in tumor tissue and neighboring healthy tissue collected from patients diagnosed with HNSCC (n = 79) in either the oral cavity, oropharynx, or larynx. We observed a pattern of differentially expressed miRNAs at each of these cancer locations. Our study showed that some of these miRNAs, separately or in combination, could serve as biomarkers distinguishing between healthy and tumor tissue, and their expression correlated with patients’ overall survival.

Ferroptosis in the tumor microenvironment: perspectives for immunotherapy

Targeting ferroptosis, which provokes lipid peroxidation in cancer cells, presents potentially new avenues for anticancer therapy. Recent studies have begun to explore how immune cells in the tumor microenvironment (TME) respond and adapt to lethal lipid peroxides (LPOs). A better understanding of this process in the TME is likely to uncover another side of ferroptosis in cancer immunity and promote the development of ferroptosis-targeted therapy. This Opinion article overviews the main metabolic processes in ferroptosis, summarizes the emerging roles of ferroptosis not only in immune cells in the TME but also in the crosstalk between tumor cells and immune cells, and presents a perspective on the targeting of ferroptosis in cancer immunotherapy.

The STING1 network regulates autophagy and cell death

Cell death and immune response are at the core of life. In past decades, the endoplasmic reticulum (ER) protein STING1 (also known as STING or TMEM173) was found to play a fundamental role in the production of type I interferons (IFNs) and pro-inflammatory cytokines in response to DNA derived from invading microbial pathogens or damaged hosts by activating multiple transcription factors. In addition to this well-known function in infection, inflammation, and immunity, emerging evidence suggests that the STING1-dependent signaling network is implicated in health and disease by regulating autophagic degradation or various cell death modalities (e.g., apoptosis, necroptosis, pyroptosis, ferroptosis, mitotic cell death, and immunogenic cell death [ICD]). Here, we outline the latest advances in our understanding of the regulating mechanisms and signaling pathways of STING1 in autophagy and cell death, which may shed light on new targets for therapeutic interventions.