The therapeutic potential of targeting regulated non-apoptotic cell death

Emerging role of necroptosis, pyroptosis, and ferroptosis in breast cancer: New dawn for overcoming therapy resistance

Breast cancer (BC) is one of the primary causes of death in women worldwide. The challenges associated with adverse outcomes have increased significantly, and the identification of novel therapeutic targets has become increasingly urgent. Regulated cell death (RCD) refers to a type of cell death that can be regulated by several different biomacromolecules, which is distinctive from accidental cell death (ACD). In recent years, apoptosis, a representative RCD pathway, has gained significance as a target for BC medications. However, tumor cells exhibit avoidance of apoptosis and result in treatment resistance, which emphasizes further studies devoted to alternative cell death processes, namely necroptosis, pyroptosis, and ferroptosis. Here, in this review, we focus on summarizing the crucial signaling pathways of these RCD in BC. We further discuss the molecular mechanism and potentiality in clinical application of several prospective drugs, nanoparticles, and other small compounds targeting different RCD subroutines of BC. We also discuss the benefits of modulating RCD processes on drug resistance and the advantages of combining RCD modulators with conventional treatments in BC. This review will deepen our understanding of the relationship between RCD and BC, and shed new light on future directions to attack cancer vulnerabilities with RCD modulators for therapeutic purposes.

Pharmacological inhibition of cGAS ameliorates postoperative cognitive dysfunction by suppressing caspase-3/GSDME-dependent pyroptosis

Neuroinflammation is a major driver of postoperative cognitive dysfunction (POCD). The cyclic GMP-AMP synthase-stimulator of interferon gene (cGAS-STING) signaling is a prominent alarming device for aberrant double-stranded DNA (dsDNA) that has emerged as a key mediator of neuroinflammation in cognitive-related diseases. However, the role of the cGAS-STING pathway in the pathogenesis of POCD remains unclear. A POCD model was developed in male C57BL/6J mice by laparotomy under isoflurane (Iso) anesthesia. The cGAS inhibitor RU.521 and caspase-3 agonist Raptinal were delivered by intraperitoneal administration. BV2 cells were exposed to Iso and lipopolysaccharide (LPS) in the absence or presence of RU.521, and then cocultured with HT22 cells in the absence or presence of Raptinal. Cognitive function was assessed using the Morris water maze test and novel object recognition test. Immunofluorescence assays were used to observe the colocalization of dsDNA and cGAS. The downstream proteins and pro-inflammatory cytokines were detected using the Western blot and enzyme-linked immunosorbent assay (ELISA). Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to assess the degree of cell death in the hippocampus following anesthesia/surgery treatment. Isoflurane/laparotomy and Iso + LPS significantly augmented the levels of cGAS in the hippocampus and BV2 cells, accompanied by mislocalized dsDNA accumulation in the cytoplasm. RU.521 alleviated cognitive impairment, diminished the levels of 2'3'-cGAMP, cGAS, STING, phosphorylated NF-κB p65 and NF-κB-pertinent pro-inflammatory cytokines (TNFα and IL-6), and repressed pyroptosis-associated elements containing cleaved caspase-3, N-GSDME, IL-1β and IL-18. These phenotypes could be rescued by Raptinal in vivo and in vitro. These findings suggest that pharmacological inhibition of cGAS mitigates neuroinflammatory burden of POCD by dampening caspase-3/GSDME-dependent pyroptosis, providing a potential therapeutic strategy for POCD.

Iron(III)-salophene catalyzes redox cycles that induce phospholipid peroxidation and deplete cancer cells of ferroptosis-protecting cofactors

Ferroptosis, a lipid peroxidation-driven cell death program kept in check by glutathione peroxidase 4 and endogenous redox cycles, promises access to novel strategies for treating therapy-resistant cancers. Chlorido [N,N'-disalicylidene-1,2-phenylenediamine]iron (III) complexes (SCs) have potent anti-cancer properties by inducing ferroptosis, apoptosis, or necroptosis through still poorly understood molecular mechanisms. Here, we show that SCs preferentially induce ferroptosis over other cell death programs in triple-negative breast cancer cells (LC50 ≥ 0.07 μM) and are particularly effective against cell lines with acquired invasiveness, chemo- or radioresistance. Redox lipidomics reveals that initiation of cell death is associated with extensive (hydroper)oxidation of arachidonic acid and adrenic acid in membrane phospholipids, specifically phosphatidylethanolamines and phosphatidylinositols, with SCs outperforming established ferroptosis inducers. Mechanistically, SCs effectively catalyze one-electron transfer reactions, likely via a redox cycle involving the reduction of Fe(III) to Fe(II) species and reversible formation of oxo-bridged dimeric complexes, as supported by cyclic voltammetry. As a result, SCs can use hydrogen peroxide to generate organic radicals but not hydroxyl radicals and oxidize membrane phospholipids and (membrane-)protective factors such as NADPH, which is depleted from cells. We conclude that SCs catalyze specific redox reactions that drive membrane peroxidation while interfering with the ability of cells, including therapy-resistant cancer cells, to detoxify phospholipid hydroperoxides.

Integrated analysis of disulfidoptosis-related genes identifies NRP1 as a novel biomarker promoting proliferation of gastric cancer via glutamine mediated energy metabolism

The incidence and mortality of gastric cancer rank fifth and fourth worldwide among all malignancies, respectively. Additionally, disulfidoptosis, a recently identified form of cellular demise, is closely linked to the initiation and advancement of malignancies. This study aims to create a novel signature of disulfidptosis-related genes (DRGs) and to further explore its association with the tumor immune microenvironment. Based on our comprehensive study, a prognostic signature consisting of 31 DRGs in stomach adenocarcinoma (STAD) was identified and characterized. Through the integrative analyses involving gene expression profiling, machine learning algorithms, and Cox regression models, the prognostic significance of these DRGs was demonstrated. Our findings highlight their strong predictive power in assessing overall survival across diverse patient datasets, and their better performance than traditional clinicopathological factors. Moreover, the DRGs signature showed association with the characteristics of the tumor microenvironment, which has implications for the immune modulation and therapeutic strategies in STAD. Specifically, NRP1 emerged as a key DRG with elevated expression in STAD, showing correlation with the advanced stages of diseases and poorer outcomes. Functional studies further revealed the role of NRP1 in promoting STAD cell proliferation through the modulation of glutamine metabolism. Overall, our study underscores the clinical relevance of DRGs as biomarker and potential therapeutic targets in STAD management, providing insights into disease biology and personalized treatments.

A copper missile-triggered power coalescence and death vortex within tumor cell mitochondria for synergistic cuproptosis/phototherapy/chemotherapy

The importance of copper homeostasis in mitochondria and copper-triggered modality of mitochondrial cell death have been confirmed. However, the existing copper-based nanoplatforms are focused on synergistic therapies while the intracellular therapeutic targets are relatively scattered. Effective integration of all targets within mitochondria to generate power coalescence remains a challenge. Herein, we developed a novel copper-based delivery system to trigger power coalescence and death vortex within tumor cell mitochondria. Specifically, a mitochondrial targeting "copper missile" loaded with curcumin (termed as Cur@CuS-TPP-HA, CCTH) was designed for cuproptosis/phototherapy/chemotherapy synergistic anti-tumor therapy. Once the CCTH NPs are shuttled to the mitochondria, near-infrared (NIR) irradiation initiates the release of copper ions and curcumin for in situ drug accumulation in cancer cell mitochondria. An excess of copper ions and curcumin can activate cuproptosis and mitochondrial apoptosis pathways, respectively. When combined, they can cause an increase in reactive oxygen species (ROS), damage to mitochondrial DNA (mt-DNA), and a decrease in energy supply, thereby leading to a "vicious circle" of mitochondrial damage that further enhances the tumor-killing efficacy. As a consequence, this "copper missile" exhibits advanced anti-tumor effects as verified through in vitro assessments and in vivo evaluations using the 4T1 breast tumor model, providing a promising approach for cuproptosis-based synergistic anti-tumor therapy.

Ubiquitin-specific protease 22 controls melanoma metastasis and vulnerability to ferroptosis through targeting SIRT1/PTEN/PI3K signaling

Metastasis is a major contributing factor that affects the prognosis of melanoma patients. Nevertheless, the underlying molecular mechanisms involved in melanoma metastasis are not yet entirely understood. Here, we identified ubiquitin-specific protease 22 (USP22) as a pro-oncogenic protein in melanoma through screening the survival profiles of 52 ubiquitin-specific proteases (USPs). USP22 demonstrates a strong association with poor clinical outcomes and is significantly overexpressed in melanoma. Ablation of USP22 expression remarkably attenuates melanoma migration, invasion, and epithelial-mesenchymal transition in vitro and suppresses melanoma metastasis in vivo. Mechanistically, USP22 controls melanoma metastasis through the SIRT1/PTEN/PI3K pathway. In addition, we conducted an United States Food and Drug Administration-approved drug library screening and identified topotecan as a clinically applicable USP22-targeting molecule by promoting proteasomal degradation of USP22. Finally, we found that both pharmacological and genetic silence of USP22 sensitize RSL3-induced ferroptosis through suppressing the PI3K/Akt/mTOR pathway and its downstream SCD, and ferroptosis inhibitor could partly rescued the decreased lung metastasis by topotecan in vivo. Overall, our findings reveal a prometastatic role of USP22 and identify topotecan as a potent USP22-targeting drug to limit melanoma metastasis.

CircPKN2 promotes ferroptosis in bladder cancer by promoting the ubiquitination of Stearoyl-CoA Desaturase 1

Bladder cancer (BC) is one of the most common malignancies in the male urinary system and currently lacks an optimal treatment strategy. To elucidate the pathogenic mechanisms of BC from the perspective of circular RNAs, we conducted this study. Building upon our previous research, a novel circRNA, circPKN2, captured our interest due to its significant downregulation in BC, and its close association with the prognosis of BC patients. Our research findings indicate that circPKN2 can inhibit the proliferation and migration of BC cells in vitro. Furthermore, we discovered that circPKN2 exerts its anti-cancer effects in BC by promoting ferroptosis. Mechanistic studies revealed that circPKN2 recruits STUB1 to facilitate the ubiquitination of SCD1, thereby suppressing the WNT pathway and promoting ferroptosis in BC. Additionally, our research unveiled the regulatory role of the splicing factor QKI in the biogenesis of circPKN2. Animal studies demonstrated that circPKN2 enhances ferroptosis in BC cells in vivo, inhibiting tumor growth and metastasis. The discovery of the anti-cancer factor circPKN2 holds promise for providing new therapeutic targets in the prevention and treatment of BC.

Harnessing pyroptosis for lung cancer therapy: The impact of NLRP3 inflammasome activation

Lung cancer is still a global health challenge in terms of high incidence, morbidity, and mortality. Recent scientific studies have determined that pyroptosis, a highly inflammatory form of programmed cell death, can be identified as a potential lung cancer therapeutic target. The NLRP3 inflammasome acts as a critical mediator in this process and, upon activation, activates multiprotein complex formation as well as caspase-1 activation. This process, triggered by a release of pro-inflammatory cytokines, results in pyroptotic cell death. Also, the relationship between the NLRP3 inflammasome and lung cancer was justified by its influence on tumour growth or metastasis. The molecular pathways produce progenitive mediators and remake the tissue. Finally, targeting NLRP3 inflammasome for pyroptosis induction and inhibition of its activation appears to be a promising lung cancer treatment approach. This technique makes cancer treatment more promising and personalized. This review explores the role of NLRP3 inflammasome activation and its possibilities in lung cancer treatment.

Carbamoylation at C-8 position of natural 3-arylcoumarin scaffold for the discovery of novel PARP-1 inhibitors with potent anticancer activity

Structural modification based on natural privileged scaffolds has proven to be an attractive approach to generate potential antitumor candidates with high potency and specific targeting. As a continuation of our efforts to identify potent PARP-1 inhibitors, natural 3-arylcoumarin scaffold was served as the starting point for the construction of novel structural unit for PARP-1 inhibition. Herein, a series of novel 8-carbamyl-3-arylcoumarin derivatives were designed and synthesized. The antiproliferative activities of target compounds against four BRCA-mutated cancer cells (SUM149PT, HCC1937, MDA-MB-436 and Capan-1) were evaluated. Among them, compound 9b exhibited excellent antiproliferative effects against SUM149PT, HCC1937 and Capan-1 cells with IC50 values of 0.62, 1.91 and 4.26 μM, respectively. Moreover, 9b could significantly inhibit the intracellular PARP-1/2 activity in SUM149PT cells with IC50 values of 2.53 nM and 6.45 nM, respectively. Further mechanism studies revealed that 9b could aggravate DNA double-strand breaks, increase ROS production, decrease mitochondrial membrane potential, arrest cell cycle at G2/M phase and ultimately induce apoptosis in SUM149PT cells. In addition, molecular docking study demonstrated that the binding mode of 9b with PARP-1 was similar to that of niraparib, forming multiple hydrogen bond interactions with the active site of PARP-1. Taken together, these findings suggest that 8-carbamyl-3-arylcoumarin scaffold could serve as an effective structural unit for PARP-1 inhibition and offer a valuable paradigm for the structural modification of natural products.

Construction and Evaluation of BAL-PTX Co-Loaded Lipid Nanosystem for Promoting the Anti-Lung Cancer Efficacy of Paclitaxel and Reducing the Toxicity of Chemotherapeutic Drugs

Purpose

The present study aimed to develop a lipid nanoplatform, denoted as "BAL-PTX-LN", co-loaded with chiral baicalin derivatives (BAL) and paclitaxel (PTX) to promote the anti-lung cancer efficacy of paclitaxel and reduce the toxicity of chemotherapeutic drugs.

Methods

BAL-PTX-LN was optimized through central composite design based on a single-factor experiments. BAL-PTX-LN was evaluated by TEM, particle size, encapsulation efficiency, hemolysis rate, release kinetics and stability. And was evaluated by pharmacokinetics and the antitumor efficacy studied both in vitro and in vivo. The in vivo safety profile of the formulation was assessed using hematoxylin and eosin (HE) staining.

Results

BAL-PTX-LN exhibited spherical morphology with a particle size of 134.36 ± 3.18 nm, PDI of 0.24 ± 0.02, and with an encapsulation efficiency exceeding 90%, BAL-PTX-LN remained stable after 180 days storage. In vitro release studies revealed a zero-order kinetic model of PTX from the liposomal formulation. No hemolysis was observed in the preparation group. Pharmacokinetic analysis of PTX in the BAL-PTX-LN group revealed an approximately three-fold higher bioavailability and twice longer t1/2 compared to the bulk drug group. Furthermore, the IC50 of BAL-PTX-LN decreased by 2.35 times (13.48 μg/mL vs 31.722 μg/mL) and the apoptosis rate increased by 1.82 times (29.38% vs 16.13%) at 24 h compared to the PTX group. In tumor-bearing nude mice, the BAL-PTX-LN formulation exhibited a two-fold higher tumor inhibition rate compared to the PTX group (62.83% vs 29.95%), accompanied by a ten-fold decrease in Ki67 expression (4.26% vs 45.88%). Interestingly, HE staining revealed no pathological changes in tissues from the BAL-PTX-LN group, whereas tissues from the PTX group exhibited pathological changes and tumor cell infiltration.

Conclusion

BAL-PTX-LN improves the therapeutic effect of poorly soluble chemotherapeutic drugs on lung cancer, which is anticipated to emerge as a viable therapeutic agent for lung cancer in clinical applications.

Inhibition of Adipocyte Necroptosis Alleviates Fat Necrosis and Fibrosis After Grafting in a Murine Model

BACKGROUND

Because of the delicate structure of the adipose tissue, fat necrosis accounts for 43.7% of all complications after autologous fat grafting; however, its regulation remains unclear.

OBJECTIVES

The purpose of this study was to examine the role of necroptosis in fat graft remodeling after grafting.

METHODS

Clinical fat graft necrosis samples were collected, and the expression levels of the necroptosis marker phosphorylated(p)-MLKL were analyzed. Transcriptome analysis was performed on fat grafts before and 1 week after transplantation in C57BL/6 mouse fat grafting models. Additionally, the in vivo effects of RIPK1 inhibitor Nec-1s or RIPK3 inhibitor GSK'872 on the fat grafting complications, including fat necrosis and fibrosis, were investigated.

RESULTS

Necroptosis markers were observed and associated with higher occurrence of fibrosis in clinical fat graft necrosis samples compared to normal fat tissue. Amplification and RNA-Seq were conducted on RNA isolated from fat grafts before and after grafting. MLKL, RIPK1, and RIPK3's expression levels were significantly upregulated in comparison to controls. Higher expression levels of necroptotic RNAs were associated with higher levels of DAMPs, including Cxcl2, HMGB1, S100a8, S100a9, Nlrp3, and IL33, and activated proinflammatory signaling pathways, including the TNF, NF-kappa B, and chemokine signaling pathways. Necroptotic inhibitor Nec-1s and GSK'872 robustly suppressed the p-MLKL expression level and significantly inhibited necroptotic cell death, especially in adipocytes. Moreover, administration of Nec-1s and GSK'872 significantly alleviated fat necrosis and subsequent fibrosis in fat grafts.

CONCLUSIONS

Collectively, our study findings highlight the potential therapeutic applications of necroptosis inhibitors in preventing fat necrosis and fibrosis after grafting.

LEVEL OF EVIDENCE: 4

Golgi protein ACBD3 downregulation sensitizes cells to ferroptosis

Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, is emerging as a promising target in cancer therapy. It is regulated by a network of molecules and pathways that modulate lipid metabolism, iron homeostasis and redox balance, and related processes. However, there are still numerous regulatory molecules intricately involved in ferroptosis that remain to be identified. Here, we indicated that suppression of Golgi protein acyl-coenzyme A binding domain A containing 3 (ACBD3) increased the sensitivity of Henrieta Lacks and PANC1 cells to ferroptosis. ACBD3 knockdown increases labile iron levels by promoting ferritinophagy. This increase in free iron, coupled with reduced levels of glutathione peroxidase 4 due to ACBD3 knockdown, leads to the accumulation of reactive oxygen species and lipid peroxides. Moreover, ACBD3 knockdown also results in elevated levels of polyunsaturated fatty acid-containing glycerophospholipids through mechanisms that remain to be elucidated. Furthermore, inhibition of ferrtinophagy in ACBD3 downregulated cells by knocking down the nuclear receptor co-activator 4 or Bafilomycin A1 treatment impeded ferroptosis. Collectively, our findings highlight the pivotal role of ACBD3 in governing cellular resistance to ferroptosis and suggest that pharmacological manipulation of ACBD3 levels is a promising strategy for cancer therapy.

Identification and validation of cuproptosis and disulfidptosis related genes in colorectal cancer

Colorectal cancer, the third most prevalent malignant cancer, is associated with poor prognosis. Recent studies have investigated the mechanisms underlying cuproptosis and disulfidptosis in colorectal cancer. However, whether genes linked to these processes impact the prognosis of colorectal cancer patients through analogous mechanisms remains unclear. In this study, we developed a model of cuproptosis and disulfidptosis in colorectal cancer and concurrently explored the role of the pivotal model gene HSPA8 in colorectal cancer cell lines. Our results revealed a positive correlation between cuproptosis and disulfidptosis, both of which are emerging as protective factors for the prognosis of CRC patients. Consequently, a prognostic model encompassing HSPA8, PDCL3, CBX3, ATP6V1G1, TAF1D, RPL4, and RPL14 was constructed. Notably, the key gene in our model, HSPA8, exhibited heightened expression and was validated as a protective prognostic factor in colorectal cancer, exerting inhibitory effects on colorectal cancer cell proliferation. This study offers novel insights into the interplay between cuproptosis and disulfidptosis. The application of the prognostic model holds promise for more effectively predicting the overall survival of colorectal cancer patients.

A Vacancy-Engineering Ferroelectric Nanomedicine for Cuproptosis/Apoptosis Co-Activated Immunotherapy

Low efficacy of immunotherapy due to the poor immunogenicity of most tumors and their insufficient infiltration by immune cells highlights the importance of inducing immunogenic cell death and activating immune system for achieving better treatment outcomes. Herein, ferroelectric Bi2CuO4 nanoparticles with rich copper vacancies (named BCO-VCu) are rationally designed and engineered for ferroelectricity-enhanced apoptosis, cuproptosis, and the subsequently evoked immunotherapy. In this structure, the suppressed recombination of the electron-hole pairs by the vacancies and the band bending by the ferroelectric polarization lead to high catalytic activity, triggering reactive oxygen species bursts and inducing apoptosis. The cell fragments produced by apoptosis serve as antigens to activate T cells. Moreover, due to the generated charge by the ferroelectric catalysis, this nanomedicine can act as "a smart switch" to open the cell membrane, promote nanomaterial endocytosis, and shut down the Cu+ outflow pathway to evoke cuproptosis, and thus a strong immune response is triggered by the reduced content of adenosine triphosphate. Ribonucleic acid transcription tests reveal the pathways related to immune response activation. Thus, this study firstly demonstrates a feasible strategy for enhancing the efficacy of immunotherapy using single ferroelectric semiconductor-induced apoptosis and cuproptosis.

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

A novel prognostic signature related to programmed cell death in osteosarcoma

Background

Osteosarcoma primarily affects children and adolescents, with current clinical treatments often resulting in poor prognosis. There has been growing evidence linking programmed cell death (PCD) to the occurrence and progression of tumors. This study aims to enhance the accuracy of OS prognosis assessment by identifying PCD-related prognostic risk genes, constructing a PCD-based OS prognostic risk model, and characterizing the function of genes within this model.

Method

We retrieved osteosarcoma patient samples from TARGET and GEO databases, and manually curated literature to summarize 15 forms of programmed cell death. We collated 1621 PCD genes from literature sources as well as databases such as KEGG and GSEA. To construct our model, we integrated ten machine learning methods including Enet, Ridge, RSF, CoxBoost, plsRcox, survivalSVM, Lasso, SuperPC, StepCox, and GBM. The optimal model was chosen based on the average C-index, and named Osteosarcoma Programmed Cell Death Score (OS-PCDS). To validate the predictive performance of our model across different datasets, we employed three independent GEO validation sets. Moreover, we assessed mRNA and protein expression levels of the genes included in our model, and investigated their impact on proliferation, migration, and apoptosis of osteosarcoma cells by gene knockdown experiments.

Result

In our extensive analysis, we identified 30 prognostic risk genes associated with programmed cell death (PCD) in osteosarcoma (OS). To assess the predictive power of these genes, we computed the C-index for various combinations. The model that employed the random survival forest (RSF) algorithm demonstrated superior predictive performance, significantly outperforming traditional approaches. This optimal model included five key genes: MTM1, MLH1, CLTCL1, EDIL3, and SQLE. To validate the relevance of these genes, we analyzed their mRNA and protein expression levels, revealing significant disparities between osteosarcoma cells and normal tissue cells. Specifically, the expression levels of these genes were markedly altered in OS cells, suggesting their critical role in tumor progression. Further functional validation was performed through gene knockdown experiments in U2OS cells. Knockdown of three of these genes-CLTCL1, EDIL3, and SQLE-resulted in substantial changes in proliferation rate, migration capacity, and apoptosis rate of osteosarcoma cells. These findings underscore the pivotal roles of these genes in the pathophysiology of osteosarcoma and highlight their potential as therapeutic targets.

Conclusion

The five genes constituting the OS-PCDS model-CLTCL1, MTM1, MLH1, EDIL3, and SQLE-were found to significantly impact the proliferation, migration, and apoptosis of osteosarcoma cells, highlighting their potential as key prognostic markers and therapeutic targets. OS-PCDS enables accurate evaluation of the prognosis in patients with osteosarcoma.

Therapeutic strategies of targeting non-apoptotic regulated cell death (RCD) with small-molecule compounds in cancer

Regulated cell death (RCD) is a controlled form of cell death orchestrated by one or more cascading signaling pathways, making it amenable to pharmacological intervention. RCD subroutines can be categorized as apoptotic or non-apoptotic and play essential roles in maintaining homeostasis, facilitating development, and modulating immunity. Accumulating evidence has recently revealed that RCD evasion is frequently the primary cause of tumor survival. Several non-apoptotic RCD subroutines have garnered attention as promising cancer therapies due to their ability to induce tumor regression and prevent relapse, comparable to apoptosis. Moreover, they offer potential solutions for overcoming the acquired resistance of tumors toward apoptotic drugs. With an increasing understanding of the underlying mechanisms governing these non-apoptotic RCD subroutines, a growing number of small-molecule compounds targeting single or multiple pathways have been discovered, providing novel strategies for current cancer therapy. In this review, we comprehensively summarized the current regulatory mechanisms of the emerging non-apoptotic RCD subroutines, mainly including autophagy-dependent cell death, ferroptosis, cuproptosis, disulfidptosis, necroptosis, pyroptosis, alkaliptosis, oxeiptosis, parthanatos, mitochondrial permeability transition (MPT)-driven necrosis, entotic cell death, NETotic cell death, lysosome-dependent cell death, and immunogenic cell death (ICD). Furthermore, we focused on discussing the pharmacological regulatory mechanisms of related small-molecule compounds. In brief, these insightful findings may provide valuable guidance for investigating individual or collaborative targeting approaches towards different RCD subroutines, ultimately driving the discovery of novel small-molecule compounds that target RCD and significantly enhance future cancer therapeutics.

Glutathione-Scavenging Celastrol-Cu Nanoparticles Induce Self-Amplified Cuproptosis for Augmented Cancer Immunotherapy

Cuproptosis is a novel copper-dependent programmed cell death. The efficacy of cuproptosis is highly dependent on intracellular copper accumulation and counteracted by a high level of glutathione (GSH) in tumor cells. Here, this work develops a self-amplified cuproptosis nanoparticles (Cel-Cu NP) using celastrol (Cel), a natural product isolated from medical plant. In Cel-Cu NP, Cel serves as a versatile copper ionophore, exhibiting an ideal coordination capacity toward copper ions without compromising the cuproptosis induction. Notably, Cel can simultaneously scavenge GSH content to amplify cuproptosis. Moreover, this self-amplified cuproptosis further activates immunogenic cell death (ICD) to elicit robust immune response. Combining with immune checkpoint blockade, Cel-Cu NP effectively eradicates metastatic tumors in a mouse lung metastasis model. This study provides an efficient nanomedicine by inducing self-amplified cuproptosis for robust immunotherapy.

Challenges of Regulated Cell Death: Implications for Therapy Resistance in Cancer

Regulated cell death, a regulatory form of cell demise, has been extensively studied in multicellular organisms. It plays a pivotal role in maintaining organismal homeostasis under normal and pathological conditions. Although alterations in various regulated cell death modes are hallmark features of tumorigenesis, they can have divergent effects on cancer cells. Consequently, there is a growing interest in targeting these mechanisms using small-molecule compounds for therapeutic purposes, with substantial progress observed across various human cancers. This review focuses on summarizing key signaling pathways associated with apoptotic and autophagy-dependent cell death. Additionally, it explores crucial pathways related to other regulated cell death modes in the context of cancer. The discussion delves into the current understanding of these processes and their implications in cancer treatment, aiming to illuminate novel strategies to combat therapy resistance and enhance overall cancer therapy.

Disulfidptosis: A new type of cell death

Disulfidptosis is a novel form of cell death that is distinguishable from established programmed cell death pathways such as apoptosis, pyroptosis, autophagy, ferroptosis, and oxeiptosis. This process is characterized by the rapid depletion of nicotinamide adenine dinucleotide phosphate (NADPH) in cells and high expression of solute carrier family 7 member 11 (SLC7A11) during glucose starvation, resulting in abnormal cystine accumulation, which subsequently induces andabnormal disulfide bond formation in actin cytoskeleton proteins, culminating in actin network collapse and disulfidptosis. This review aimed to summarize the underlying mechanisms, influencing factors, comparisons with traditional cell death pathways, associations with related diseases, application prospects, and future research directions related to disulfidptosis.

Spotlight on macrophage pyroptosis: A bibliometric and visual analysis from 2001 to 2023

Macrophage pyroptosis plays a significant role in the pathogenesis of various diseases, especially acute lung injury, atherosclerosis, and sepsis. Despite its importance, analysis of the existing literature has been limited. Therefore, we conducted a bibliometric analysis to provide a comprehensive overview of research on macrophage pyroptosis and identify the current research foci and trends in this field. We collected articles related to macrophage pyroptosis published between 2001 and 2022 from the Web of Science Core Collection and PubMed. Citespace, VOSviewer, bibliometrix R package, and Microsoft Excel 2019 were used to analyze co-occurrence relationships and the contribution of countries/regions, institutions, journals, authors, references, and keywords. In total, 1321 papers were included. China and the United States of America published the most articles in this field. TD Kanneganti had the most publications; BT Cookson was the most cited. Although China contributed the most publications, it had a relatively low ratio of multiple-country collaborations (0.132). Among journals, Frontiers in Immunology and Cell Death Disease published the most papers; Nature and the Journal of Immunology were frequently co-cited. Frequently occurring keywords included "inflammation," "NLRP3 inflammasome," "apoptosis," "caspase-1," and "cell death." Moreover, with the advancement of gene editing technology and the integration of clinical applications, novel molecules ("caspases," "GSDMD," "ASC"), programmed cell death topics ("pyroptosis," "ferroptosis," "necrosis"), and clinical applications ("alveolar macrophage," "atherosclerosis," "prognosis") emerged as frontiers. The macrophage pyroptosis field is rapidly evolving and holds promise as a potential target for treating macrophage pyroptosis-related diseases.

Mn(II)-Aloe-Emodin Nanoscale Coordination Polymer Enhances Ferroptosis by Synergistically Enhancing Reactive Oxygen Species Generation via the Nrf2-GPX4 Axis

Ferroptosis induction is particularly promising for cancer therapy when the apoptosis pathway is compromised. Current strategies in nanomedicine for inducing ferroptosis primarily focus on promoting the accumulation of reactive oxygen species (ROS). However, the presence of intracellular antioxidants, such as nuclear factor erythroid 2-related factor 2 (Nrf2), can limit the effectiveness of such therapy by activating detoxification systems and eliminating ROS. To overcome this challenge, we developed a synergistic ferroptosis-inducing agent by modifying manganese (Mn2+)-1,8-dihydroxy-3-hydroxymethyl-anthraquinone (aloe-emodin, AE) with polyvinyl pyrrolidone (PVP) to create nanoparticles (MAP NPs). In the tumor microenvironment, these NPs degraded and released AE and Mn(II), facilitating the generation of ROS and Mn(IV) through a Fenton-like reaction between hydrogen peroxide (H2O2) and Mn(II). Mn(IV) subsequently interacts with glutathione (GSH) to induce a cyclic catalytic effect, and the depletion of GSH diminished the activation of glutathione-dependent peroxidase 4 (GPX4). Furthermore, AE inhibits the activity of Nrf2 and depleted GSH, thereby synergistically enhancing antitumor efficacy. Here it is demonstrated that MAP NPs effectively generate a robust ROS storm within tumor cells, suggesting that high-performance ferroptosis therapy is effective. Additionally, the inclusion of Mn(II) in the MAP NPs enables real-time monitoring of therapeutic efficacy via magnetic resonance T1-weighted contrast imaging.

Discovery of Novel Ortho-Aminophenol Derivatives Targeting Lipid Peroxidation with Potent Antiferroptotic Activities

The concept of ferroptosis inhibition has gained growing recognition as a promising therapeutic strategy for addressing a wide range of diseases. Here, we present the discovery of four series of ortho-aminophenol derivatives as potential ferroptosis inhibitors beginning with the endogenous substance 3-hydroxyanthranilic acid (3-HA) by employing quantum chemistry techniques, in vitro and in vivo assays. Our findings reveal that these ortho-aminophenol derivatives exhibit unique intra-H bond interactions, compelling ortho-amines to achieve enhanced alignment with the aromatic π-system, thereby expanding their activity. Notably, compounds from all four series display remarkable activity against RSL3-induced ferroptosis, showcasing an activity 100 times more than that of 3-HA. Furthermore, these compounds also demonstrate robust in vivo efficacy in protecting mice from kidney ischemia-reperfusion injury and acetaminophen-induced hepatotoxicity. In summary, we provide four distinct series of active scaffolds that significantly expand the chemical space of ferroptosis inhibitors, serving as valuable insights for future structural modifications.

Developing a prognostic model using machine learning for disulfidptosis related lncRNA in lung adenocarcinoma

Disulfidptosis represents a novel cell death mechanism triggered by disulfide stress, with potential implications for advancements in cancer treatments. Although emerging evidence highlights the critical regulatory roles of long non-coding RNAs (lncRNAs) in the pathobiology of lung adenocarcinoma (LUAD), research into lncRNAs specifically associated with disulfidptosis in LUAD, termed disulfidptosis-related lncRNAs (DRLs), remains insufficiently explored. Using The Cancer Genome Atlas (TCGA)-LUAD dataset, we implemented ten machine learning techniques, resulting in 101 distinct model configurations. To assess the predictive accuracy of our model, we employed both the concordance index (C-index) and receiver operating characteristic (ROC) curve analyses. For a deeper understanding of the underlying biological pathways, we referred to the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) for functional enrichment analysis. Moreover, we explored differences in the tumor microenvironment between high-risk and low-risk patient cohorts. Additionally, we thoroughly assessed the prognostic value of the DRLs signatures in predicting treatment outcomes. The Kaplan-Meier (KM) survival analysis demonstrated a significant difference in overall survival (OS) between the high-risk and low-risk cohorts (p < 0.001). The prognostic model showed robust performance, with an area under the ROC curve exceeding 0.75 at one year and maintaining a value above 0.72 in the two and three-year follow-ups. Further research identified variations in tumor mutational burden (TMB) and differential responses to immunotherapies and chemotherapies. Our validation, using three GEO datasets (GSE31210, GSE30219, and GSE50081), revealed that the C-index exceeded 0.67 for GSE31210 and GSE30219. Significant differences in disease-free survival (DFS) and OS were observed across all validation cohorts among different risk groups. The prognostic model offers potential as a molecular biomarker for LUAD prognosis.

Bioinformatics analysis of signature genes related to cell death in keratoconus

Keratoconus is corneal disease in which the progression of conical dilation of cornea leads to reduced visual acuity and even corneal perforation. However, the etiology mechanism of keratoconus is still unclear. This study aims to identify the signature genes related to cell death in keratoconus and examine the function of these genes. A dataset of keratoconus from the GEO database was analysed to identify the differentially expressed genes (DEGs). A total of 3558 DEGs were screened from GSE151631. The results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that they mainly involved in response to hypoxia, cell-cell adhesion, and IL-17 signaling pathway. Then, the cell death-related genes datasets were intersected with the above 3558 DEGs to obtain 70 ferroptosis-related DEGs (FDEGs), 32 autophagy-related DEGs (ADEGs), six pyroptosis-related DEGs (PDEGs), four disulfidptosis-related DEGs (DDEGs), and one cuproptosis-related DEGs (CDEGs). After using Least absolute shrinkage and selection operator (LASSO), Random Forest analysis, and receiver operating characteristic (ROC) curve analysis, one ferroptosis-related gene (TNFAIP3) and five autophagy-related genes (CDKN1A, HSPA5, MAPK8IP1, PPP1R15A, and VEGFA) were screened out. The expressions of the above six genes were significantly decreased in keratoconus and the area under the curve (AUC) values of these genes was 0.944, 0.893, 0.797, 0.726, 0.882 and 0.779 respectively. GSEA analysis showed that the above six genes mainly play an important role in allograft rejection, asthma, and circadian rhythm etc. In conclusion, the results of this study suggested that focusing on these genes and autoimmune diseases will be a beneficial perspective for the keratoconus etiology research.

Involvement of multiple forms of cell death in patulin-induced toxicities

Patulin (PAT) is the most common mycotoxin found in moldy fruits and their derived products, and is reported to cause diverse toxic effects, including hepatotoxicity, nephrotoxicity, cardiotoxicity, neurotoxicity, immunotoxicity, gastrointestinal toxicity and dermal toxicity. The cell death induction by PAT is suggested to be a key cellular mechanism involved in PAT-induced toxicities. Accumulating evidence indicates that the multiple forms of cell death are induced in response to PAT exposure, including apoptosis, autophagic cell death, pyroptosis and ferroptosis. Mechanistically, the cell death induction by PAT is associated the oxidative stress induction via reducing the antioxidant capacity or inducing pro-oxidant NADPH oxidase, the activation of mitochondrial pathway via regulating BCL-2 family proteins, the disruption of iron metabolism through ferritinophagy-mediated ferritin degradation, and the induction of the NOD-like receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome/caspase-1/gasdermin D (GSDMD) pathway. In this review article, we summarize the present understanding of the cell death induction by PAT, discuss the potential signaling pathways underlying PAT-induced cell death, and propose the issues that need to be addressed to promote the development of cell death-based approach to counteract PAT-induced toxicities.

Targeting immunogenic cell stress and death for cancer therapy

Immunogenic cell death (ICD), which results from insufficient cellular adaptation to specific stressors, occupies a central position in the development of novel anticancer treatments. Several therapeutic strategies to elicit ICD - either as standalone approaches or as means to convert immunologically cold tumours that are insensitive to immunotherapy into hot and immunotherapy-sensitive lesions - are being actively pursued. However, the development of ICD-inducing treatments is hindered by various obstacles. Some of these relate to the intrinsic complexity of cancer cell biology, whereas others arise from the use of conventional therapeutic strategies that were developed according to immune-agnostic principles. Moreover, current discovery platforms for the development of novel ICD inducers suffer from limitations that must be addressed to improve bench-to-bedside translational efforts. An improved appreciation of the conceptual difference between key factors that discriminate distinct forms of cell death will assist the design of clinically viable ICD inducers.

Targeting regulated cell death (RCD) in hematological malignancies: Recent advances and therapeutic potential

Regulated cell death (RCD) is a form of cell death that can be regulated by numerous biomacromolecules. Accumulating evidence suggests that dysregulated expression and altered localization of related proteins in RCD promote the development of cancer. Targeting subroutines of RCD with pharmacological small-molecule compounds is becoming a promising therapeutic avenue for anti-tumor treatment, especially in hematological malignancies. Herein, we summarize the aberrant mechanisms of apoptosis, necroptosis, pyroptosis, PANoptosis, and ferroptosis in hematological malignancies. In particular, we focus on the relationship between cell death and tumorigenesis, anti-tumor immunotherapy, and drug resistance in hematological malignancies. Furthermore, we discuss the emerging therapeutic strategies targeting different RCD subroutines. This review aims to summarize the significance and potential mechanisms of RCD in hematological malignancies, along with the development and utilization of pertinent therapeutic strategies.

Application of natural products in regulating ferroptosis in human diseases

BACKGROUND

Ferroptosis is a type of cell death caused by excessive iron-induced peroxidation. It has been found to be involved in a variety of diseases, and natural products can be used to target ferroptosis in treatments. Natural products are biologically active compounds extracted or synthesized from nature. It is an important resource for the discovery of skeletons with a high degree of structural diversity and a wide range of bioactivities, which can be developed directly or used as a starting point for the optimization of new drugs.

PURPOSE

In this review, we aim to discuss the interactions between natural products and ferroptosis in the treatment of human diseases.

METHODS

Literature was searched in Pubmed, Science Direct, and Web of Science databases for the 11-year period from 2012 to 2023 using the search terms "natural products", "ferroptosis", "human disease", "neurodegenerative disease", "cardiovascular disease", and "cancer".

RESULTS

In this research, the roles of natural products and ferroptosis were investigated. We suggest that natural products, such as terpenoids, flavonoids, polyphenols, alkaloids, and saponins, can be used in therapeutic applications for human diseases, as well as in ferroptosis. Additionally, the main mechanisms of ferroptosis were summarized and discussed. Furthermore, we propose that natural products can be utilized to enhance the sensitivity of cancer cells to ferroptosis, thus helping to overcome drug resistance and inhibit metastasis. Moreover, natural products have the potential to modulate the expression levels of ferroptosis-related factors. Finally, the future directions of this field were highlighted.

CONCLUSION

The potential of natural products which focus on ferroptosis to treat human illnesses, particularly cancer, is very encouraging for human wellbeing.

Role of Exosomes in Cancer and Aptamer-Modified Exosomes as a Promising Platform for Cancer Targeted Therapy

Exosomes are increasingly recognized as important mediators of intercellular communication in cancer biology. Exosomes can be derived from cancer cells as well as cellular components in tumor microenvironment. After secretion, the exosomes carrying a wide range of bioactive cargos can be ingested by local or distant recipient cells. The released cargos act through a variety of mechanisms to elicit multiple biological effects and impact most if not all hallmarks of cancer. Moreover, owing to their excellent biocompatibility and capability of being easily engineered or modified, exosomes are currently exploited as a promising platform for cancer targeted therapy. In this review, we first summarize the current knowledge of roles of exosomes in risk and etiology, initiation and progression of cancer, as well as their underlying molecular mechanisms. The aptamer-modified exosome as a promising platform for cancer targeted therapy is then briefly introduced. We also discuss the future directions for emerging roles of exosome in tumor biology and perspective of aptamer-modified exosomes in cancer therapy.

Improved Immunotherapy Outcomes via Cuproptosis Upregulation of HLA-DRA Expression: Promoting the Aggregation of CD4+ and CD8+T Lymphocytes in Clear Cell Renal Cell Carcinoma

Immunotherapy has shown promising clinical results in clear cell renal cell carcinoma (ccRCC), but low clinical target response rates due to dysfunction of the major histocompatibility complex (MHC) and an inhibitory tumor immune microenvironment (TIME) have largely limited the associated clinical benefits. In the present study, we explored the feasibility of enhancing tumor-specific-MHC-II-HLA-DRA expression, counteracting the TIME's suppressive effects, thereby improving the sensitivity of immune checkpoint inhibitor (ICI) therapy from the standpoint of cuproptosis. Immunohistochemical staining and in vitro experiments validated the expression of HLA-DRA in ccRCC and its positive impact on ICI therapy. Subsequently, we observed that cuproptosis upregulated HLA-DRA expression in a dose-dependent manner, further confirming the link between cuproptosis and HLA-DRA. In vivo experiments showed that cuproptosis increased the sensitivity to ICI treatment, and implementing cuproptosis alongside anti-PD-1 treatment curtailed tumor growth. Mechanistically, cuproptosis upregulates HLA-DRA expression at the transcriptional level in a dose-dependent manner by inducing the production of reactive oxygen species; high levels of HLA-DRA promote the expression of chemokines CCL5, CXCL9, and CXCL10 in the TIME, inhibiting the development of a pro-tumor microenvironment by promoting the infiltration of CD4+T and CD8+T cells, thereby synergizing ICI therapy and exerting anti-tumor effects. Taken together, this work highlights the role of cuproptosis in mediating TIME remodeling and synergistic immunotherapy, providing new evidence that cuproptosis can evoke effective anti-tumor immune responses.

Stimulation of tumoricidal immunity via bacteriotherapy inhibits glioblastoma relapse

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor characterized by invasive behavior and a compromised immune response, presenting treatment challenges. Surgical debulking of GBM fails to address its highly infiltrative nature, leaving neoplastic satellites in an environment characterized by impaired immune surveillance, ultimately paving the way for tumor recurrence. Tracking and eradicating residual GBM cells by boosting antitumor immunity is critical for preventing postoperative relapse, but effective immunotherapeutic strategies remain elusive. Here, we report a cavity-injectable bacterium-hydrogel superstructure that targets GBM satellites around the cavity, triggers GBM pyroptosis, and initiates innate and adaptive immune responses, which prevent postoperative GBM relapse in male mice. The immunostimulatory Salmonella delivery vehicles (SDVs) engineered from attenuated Salmonella typhimurium (VNP20009) seek and attack GBM cells. Salmonella lysis-inducing nanocapsules (SLINs), designed to trigger autolysis, are tethered to the SDVs, eliciting antitumor immune response through the intracellular release of bacterial components. Furthermore, SDVs and SLINs administration via intracavitary injection of the ATP-responsive hydrogel can recruit phagocytes and promote antigen presentation, initiating an adaptive immune response. Therefore, our work offers a local bacteriotherapy for stimulating anti-GBM immunity, with potential applicability for patients facing malignancies at a high risk of recurrence.

LINC00606 promotes glioblastoma progression through sponge miR-486-3p and interaction with ATP11B

BACKGROUND

LncRNAs regulate tumorigenesis and development in a variety of cancers. We substantiate for the first time that LINC00606 is considerably expressed in glioblastoma (GBM) patient specimens and is linked with adverse prognosis. This suggests that LINC00606 may have the potential to regulate glioma genesis and progression, and that the biological functions and molecular mechanisms of LINC00606 in GBM remain largely unknown.

METHODS

The expression of LINC00606 and ATP11B in glioma and normal brain tissues was evaluated by qPCR, and the biological functions of the LINC00606/miR-486-3p/TCF12/ATP11B axis in GBM were verified through a series of in vitro and in vivo experiments. The molecular mechanism of LINC00606 was elucidated by immunoblotting, FISH, RNA pulldown, CHIP-qPCR, and a dual-luciferase reporter assay.

RESULTS

We demonstrated that LINC00606 promotes glioma cell proliferation, clonal expansion and migration, while reducing apoptosis levels. Mechanistically, on the one hand, LINC00606 can sponge miR-486-3p; the target gene TCF12 of miR-486-3p affects the transcriptional initiation of LINC00606, PTEN and KLLN. On the other hand, it can also regulate the PI3K/AKT signaling pathway to mediate glioma cell proliferation, migration and apoptosis by binding to ATP11B protein.

CONCLUSIONS

Overall, the LINC00606/miR-486-3p/TCF12/ATP11B axis is involved in the regulation of GBM progression and plays a role in tumor regulation at transcriptional and post-transcriptional levels primarily through LINC00606 sponging miR-486-3p and targeted binding to ATP11B. Therefore, our research on the regulatory network LINC00606 could be a novel therapeutic strategy for the treatment of GBM.

Mechanism of metal ion-induced cell death in gastrointestinal cancer

Gastrointestinal (GI) cancer is one of the most severe types of cancer, with a significant impact on human health worldwide. Due to the urgent demand for more effective therapeutic strategies against GI cancers, novel research on metal ions for treating GI cancers has attracted increasing attention. Currently, with accumulating research on the relationship between metal ions and cancer therapy, several metal ions have been discovered to induce cell death. In particular, the three novel modes of cell death, including ferroptosis, cuproptosis, and calcicoptosis, have become focal points of research in the field of cancer. Meanwhile, other metal ions have also been found to trigger cell death through various mechanisms. Accordingly, this review focuses on the mechanisms of metal ion-induced cell death in GI cancers, hoping to provide theoretical support for further GI cancer therapies.

Unraveling the intriguing interplay: Exploring the role of lncRNAs in caspase-independent cell death

Cell death plays a crucial role in various physiological and pathological processes. Until recently, programmed cell death was mainly attributed to caspase-dependent apoptosis. However, emerging evidence suggests that caspase-independent cell death (CICD) mechanisms also contribute significantly to cellular demise. We and others have reported and functionally characterized numerous long noncoding RNAs (lncRNAs) that modulate caspase-dependent apoptotic pathways potentially in a pathway-dependent manner. However, the interplay between lncRNAs and CICD pathways has not been comprehensively documented. One major reason for this is that most CICD pathways have been recently discovered with some being partially characterized at the molecular level. In this review, we discuss the emerging evidence that implicates specific lncRNAs in the regulation and execution of CICD. We summarize the diverse mechanisms through which lncRNAs modulate different forms of CICD, including ferroptosis, necroptosis, cuproptosis, and others. Furthermore, we highlight the intricate regulatory networks involving lncRNAs, protein-coding genes, and signaling pathways that orchestrate CICD in health and disease. Understanding the molecular mechanisms and functional implications of lncRNAs in CICD may unravel novel therapeutic targets and diagnostic tools for various diseases, paving the way for innovative strategies in disease management and personalized medicine. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Bioactive Layered Double Hydroxides for Synergistic Sonodynamic/Cuproptosis Anticancer Therapy with Elicitation of the Immune Response

Sonodynamic therapy (SDT) has promising application prospects in tumor therapy. However, SDT does not eradicate metastatic tumors. Herein, Cu-substituted ZnAl ternary layered double hydroxide nanosheets (ZCA NSs) were developed as both sonosensitizers and copper nanocarriers for synergistic SDT/cuproptosis cancer therapy. An optimized electronic structure more conducive to the sonodynamic process was obtained from ZCA NSs via the Jahn-Teller effect induced by the introduction of Cu2+, and the synthesized ZCA NSs regulated the intricate tumor microenvironment (TME) by depleting endogenous glutathione (GSH) to amplify oxidative stress for further enhanced SDT performance. Furthermore, cuproptosis was evoked by intracellular overload of Cu2+ and amplified by SDT, leading to irreversible proteotoxicity. In vitro results showed that such synergetic SDT/cuproptosis triggered immunogenic cell death (ICD) and promoted the maturation of dendritic cells (DCs). Furthermore, the as-synthesized ZCA NS-mediated SDT/cuproptosis thoroughly eradicated the in vivo solid tumors and simultaneously elicited antitumor immunity to suppress lung and liver metastasis. Overall, this work established a nanoplatform for synergistic SDT/cuproptosis with a satisfactory antitumor immunity.

The roles of ferroptosis in cancer: Tumor suppression, tumor microenvironment, and therapeutic interventions

In cancer treatment, the recurrent challenge of inducing apoptosis through conventional therapeutic modalities, often thwarted by therapy resistance, emphasizes the critical need to explore alternative cell death pathways. Ferroptosis, an iron-dependent form of regulated cell death triggered by the lethal accumulation of lipid peroxides on cellular membranes, has emerged as one such promising frontier in oncology. Induction of ferroptosis not only suppresses tumor growth but also holds potential for augmenting immunotherapy responses and surmounting resistance to existing cancer therapies. This review navigates the role of ferroptosis in tumor suppression. Furthermore, we delve into the complex role of ferroptosis within the tumor microenvironment and its interplay with antitumor immunity, offering insights into the prospect of targeting ferroptosis as a strategic approach in cancer therapy.

Ferroptosis and HMGB2 induced calreticulin translocation required for immunogenic cell death are controlled by the nuclear exporter XPO1

Cisplatin and oxaliplatin cause the secretion of high mobility group box 1 (HMGB1) from cancer cells, which is necessary for initiation of immunogenic cell death (ICD). Calreticulin (CRT) translocation from the endoplasmic reticulum to the plasma membrane is also required; oxaliplatin induces this translocation but cisplatin does not. We have discovered that oxaliplatin causes the secretion of both HMGB1 and HMGB2 from the nucleus into the extracellular milieu. We previously showed that cisplatin mediated secretion of HMGB1 is controlled by the nuclear exporter XPO1 (chromosomal maintenance 1; CRM1). We now find that XPO1 regulates oxaliplatin mediated secretion of both HMGB1 and HMGB2. XPO1 inhibition causes nuclear accumulation of both proteins, inhibition of oxaliplatin-mediated ferroptosis of colon cancer cells, and inhibition of CRT translocation to the plasma membrane of lung and colon cancer cells. Incubation of cancer cells with cell targeted (CT)-HMGB2 confirmed that HMGB2 is responsible for translocation of CRT to the plasma membrane. CT-HMGB2 is three orders of magnitude more potent than oxaliplatin at inducing CRT translocation. Inhibition of HMGB1 and HMGB2 secretion and/or their activation of nuclear factor-kappa B (NF-kB) has potential utility for treating cardiovascular, and neurodegenerative diseases; whereas CT-HMGB2 could augment therapeutic approaches to cancer treatment.

SBFI26 induces triple-negative breast cancer cells ferroptosis via lipid peroxidation

SBFI26, an inhibitor of FABP5, has been shown to suppress the proliferation and metastasis of tumour cells. However, the underlying mechanism by which SBFI26 induces ferroptosis in breast cancer cells remains largely unknown. Three breast cancer cell lines were treated with SBFI26 and CCK-8 assessed cytotoxicity. Transcriptome was performed on the Illumina platform and verified by qPCR. Western blot evaluated protein levels. Malondialdehyde (MDA), total superoxide dismutase (T-SOD), Fe, glutathione (GSH) and oxidized glutathione (GSSG) were measured. SBFI26 induced cell death time- and dose-dependent, with a more significant inhibitory effect on MDA-MB-231 cells. Fer-1, GSH and Vitamin C attenuated the effects but not erastin. RNA-Seq analysis revealed that SBFI26 treatment significantly enriched differentially expressed genes related to ferroptosis. Furthermore, SBFI26 increased intracellular MDA, iron ion, and GSSG levels while decreasing T-SOD, total glutathione (T-GSH), and GSH levels.SBFI26 dose-dependently up-regulates the expression of HMOX1 and ALOX12 at both gene and protein levels, promoting ferroptosis. Similarly, it significantly increases the expression of SAT1, ALOX5, ALOX15, ALOXE3 and CHAC1 that, promoting ferroptosis while downregulating the NFE2L2 gene and protein that inhibit ferroptosis. SBFI26 leads to cellular accumulation of fatty acids, which triggers excess ferrous ions and subsequent lipid peroxidation for inducing ferroptosis.

Analysis of network expression and immune infiltration of disulfidptosis-related genes in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a globally prevalent respiratory disease, and programmed cell death plays a pivotal role in the development of COPD. Disulfidptosis is a newly discovered type of cell death that may be associated with the progression of COPD. However, the expression and role of disulfidptosis-related genes (DRGs) in COPD remain unclear.

METHODS

The expression of DRGs was identified by analyzing RNA sequencing (RNA-seq) data in COPD. Further, COPD patients were classified into two subtypes by unsupervised cluster analysis to reveal their differences in gene expression and immune infiltration. Meanwhile, hub genes associated with disulfidptosis were screened by weighted gene co-expression network analysis. Subsequently, the hub genes were validated experimentally in cells and animals. In addition, we screened potential therapeutic drugs through the hub genes.

RESULTS

We identified two distinct molecular clusters and observed significant differences in immune cell populations between them. In addition, we screened nine hub genes, and experimental validation showed that CDC71, DOHH, PDAP1, and SLC25A39 were significantly upregulated in cigarette smoke-induced COPD mouse lung tissues and bronchial epithelial cells (BEAS-2B) treated with cigarette smoke extract. Finally, we predicted 10 potential small molecule drugs such as Atovaquone, Taurocholic acid, Latamoxef, and Methotrexate.

CONCLUSION

We highlighted the strong association between COPD and disulfidptosis, with DRGs demonstrating a discriminative capacity for COPD. Additionally, the expression of certain novel genes, including CDC71, DOHH, PDAP1, and SLC25A39, is linked to COPD and may aid in the diagnosis and assessment of this condition.

Machine learning-driven prognostic analysis of cuproptosis and disulfidptosis-related lncRNAs in clear cell renal cell carcinoma: a step towards precision oncology

Cuproptosis and disulfidptosis, recently discovered mechanisms of cell death, have demonstrated that differential expression of key genes and long non-coding RNAs (lncRNAs) profoundly influences tumor development and affects their drug sensitivity. Clear cell renal cell carcinoma (ccRCC), the most common subtype of kidney cancer, presently lacks research utilizing cuproptosis and disulfidptosis-related lncRNAs (CDRLRs) as prognostic markers. In this study, we analyzed RNA-seq data, clinical information, and mutation data from The Cancer Genome Atlas (TCGA) on ccRCC and cross-referenced it with known cuproptosis and disulfidptosis-related genes (CDRGs). Using the LASSO machine learning algorithm, we identified four CDRLRs-ACVR2B-AS1, AC095055.1, AL161782.1, and MANEA-DT-that are strongly associated with prognosis and used them to construct a prognostic risk model. To verify the model's reliability and validate these four CDRLRs as significant prognostic factors, we performed dataset grouping validation, followed by RT-qPCR and external database validation for differential expression and prognosis of CDRLRs in ccRCC. Gene function and pathway analysis were conducted using Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) for high- and low-risk groups. Additionally, we have analyzed the tumor mutation burden (TMB) and the immune microenvironment (TME), employing the oncoPredict and Immunophenoscore (IPS) algorithms to assess the sensitivity of diverse risk categories to targeted therapeutics and immunosuppressants. Our predominant objective is to refine prognostic predictions for patients with ccRCC and inform treatment decisions by conducting an exhaustive study on cuproptosis and disulfidptosis.

Utilizing Extracellular Vesicles for Eliminating 'Unwanted Molecules': Harnessing Nature's Structures in Modern Therapeutic Strategies

Extracellular vesicles (EVs) are small phospholipid bilayer-bond structures released by diverse cell types into the extracellular environment, maintaining homeostasis of the cell by balancing cellular stress. This article provides a comprehensive overview of extracellular vesicles, their heterogeneity, and diversified roles in cellular processes, emphasizing their importance in the elimination of unwanted molecules. They play a role in regulating oxidative stress, particularly by discarding oxidized toxic molecules. Furthermore, endoplasmic reticulum stress induces the release of EVs, contributing to distinct results, including autophagy or ER stress transmission to following cells. ER stress-induced autophagy is a part of unfolded protein response (UPR) and protects cells from ER stress-related apoptosis. Mitochondrial-derived vesicles (MDVs) also play a role in maintaining homeostasis, as they carry damaged mitochondrial components, thereby preventing inflammation. Moreover, EVs partake in regulating aging-related processes, and therefore they can potentially play a crucial role in anti-aging therapies, including the treatment of age-related diseases such as Alzheimer's disease or cardiovascular conditions. Overall, the purpose of this article is to provide a better understanding of EVs as significant mediators in both physiological and pathological processes, and to shed light on their potential for therapeutic interventions targeting EV-mediated pathways in various pathological conditions, with an emphasis on age-related diseases.

Diazepam-based covalent modifiers of GPX4 induce ferroptosis in liver cancer cells

Developing new chemotherapeutics that are structurally and mechanistically unique is needed due to the rapid rise of the cancer incidence across the globe. Here, we report the identification of irreversible, thiol-reactive diazepam derivatives as GPX4 modifiers and nanomolar inducers of ferroptosis in liver cancer cells.

Paracrine signaling of ferroptotic airway epithelium in crystalline silica-induced pulmonary fibrosis augments local fibroblast activation through glycolysis reprogramming

Chronic exposure to crystalline silica (CS) contributes to pulmonary fibrosis. Airway epithelium dysfunction and fibroblast activation have both been recognized as pivotal players, alongside disturbances in ferroptosis and glycolysis reprogramming. However, the mechanisms involved remain unclear. In this study, we investigated the crosstalk between airway epithelium and fibroblast in the context of CS-induced pulmonary fibrosis. CS was employed in vivo and the in vitro co-culture system of airway epithelium and fibroblast. Spatial transcriptome analysis of CS-induced fibrotic lung tissue was conducted as well. Results showed that epithelium ferroptosis caused by CS enhanced TGFβ1-induced fibroblast activation through paracrine signaling. tPA was further identified to be the central mediator that bridges epithelium ferroptosis and fibroblast activation. And increased fibroblast glycolysis reprogramming was evidenced to promote fibroblast activation. By inhibition of epithelium ferroptosis or silencing tPA of airway epithelium, fibroblast AMPK phosphorylation was inhibited. Moreover, we revealed that tPA secreted by ferroptotic epithelium transmits paracrine signals to fibroblasts by governing glycolysis via p-AMPK/AMPK mediated Glut1 accumulation. Collectively, our study demonstrated the regulation of airway epithelium ferroptosis on fibroblast activation in CS-induced pulmonary fibrosis, which would shed light on the complex cellular crosstalk within pulmonary fibrosis and identify potential therapeutic targets.

NAT10 promotes renal ischemia-reperfusion injury via activating NCOA4-mediated ferroptosis

Ischemia-reperfusion injury (IRI) is a significant contributor to acute kidney injury (AKI) and is associated with substantial morbidity and mortality rates. In this study, we aimed to investigate the role of NAT10 and its ac4C RNA modification in IRI-induced renal injury. Our findings revealed that both the expression level of NAT10 and the RNA ac4C level in the kidneys were elevated in the IRI group compared to the sham group. Functionally, we observed that inhibition of NAT10 activity with Remodelin or the specific knockout of NAT10 in the kidney led to a significant attenuation of IRI-induced renal injury. Furthermore, in vitro experiments demonstrated that NAT10 inhibition and specific knockout of NAT10 in the kidney markedly suppressed global ac4C RNA modification, providing protection against hypoxia/reoxygenation-induced tubular epithelial cell injury and ferroptosis. Mechanistically, our study uncovered that NAT10 promoted ac4C RNA modification of NCOA4 mRNA, thereby enhancing its stability and contributing to IRI-induced ferroptosis in tubular epithelial cells (TECs). These findings underscore the potential of NAT10 and ac4C RNA modification as promising therapeutic targets for the treatment of AKI. Overall, our study sheds light on the critical involvement of NAT10 and ac4C RNA modification in the pathogenesis of IRI-induced renal injury, offering valuable insights for the development of novel AKI treatment strategies.

Osteoking promotes bone formation and bone defect repair through ZBP1-STAT1-PKR-MLKL-mediated necroptosis

BACKGROUND

Osteoking has been used for fracture therapy with a satisfying clinical efficacy. However, its therapeutic properties and the underlying mechanisms remain elusive.

METHOD

A bone defect rat model was established to evaluate the pharmacological effects of Osteoking by the dynamic observation of X-ray, micro-CT and histopathologic examination. Transcriptome profiling was performed to identify bone defect-related genes and Osteoking effective targets. Then, a "disease-related gene-drug target" interaction network was constructed and a list of key network targets were screened, which were experimentally verified.

RESULTS

Osteoking effectively promoted bone defect repair in rats by accelerating the repair of cortical bone and the growth of trabeculae. Histopathologically, the bone defect rats displayed lower histopathologic scores in cortical bone, cancellous bone and bone connection than normal controls. In contrast, Osteoking exerted a favorable effect with a dose-dependent manner. The abnormal serum levels of bone turnover markers, bone growth factors and bone metabolism-related biochemical indexes in bone defect rats were also reversed by Osteoking treatment. Following the transcriptome-based network investigation, we hypothesized that osteoking might attenuate the levels of ZBP1-STAT1-PKR-MLKL-mediated necroptosis involved into bone defect. Experimentally, the expression levels of ZBP1, STAT1, PKR and the hallmark inflammatory cytokines for the end of necroptosis were distinctly elevated in bone defect rats, but were all effectively reversed by Osteoking treatment, which were also suppressed the activities of RIPK1, RIPK3 and MLKL in bone tissue supernatants.

CONCLUSIONS

Osteoking may promote bone formation and bone defect repair by regulating ZBP1-STAT1-PKR axis, leading to inhibit RIPK1/RIPK3/MLKL activation-mediated necroptosis.

Autophagy and Apoptosis in Rabies Virus Replication

Rabies virus (RABV) is a single-stranded negative-sense RNA virus belonging to the Rhabdoviridae family and Lyssavirus genus, which is highly neurotropic and can infect almost all warm-blooded animals, including humans. Autophagy and apoptosis are two evolutionarily conserved and genetically regulated processes that maintain cellular and organismal homeostasis, respectively. Autophagy recycles unnecessary or dysfunctional intracellular organelles and molecules in a cell, whereas apoptosis eliminates damaged or unwanted cells in an organism. Studies have shown that RABV can induce both autophagy and apoptosis in target cells. To advance our understanding of pathogenesis of rabies, this paper reviews the molecular mechanisms of autophagy and apoptosis induced by RABV and the effects of the two cellular events on RABV replication.

Bioinformatics reveals diagnostic potential of cuproptosis-related genes in the pathogenesis of sepsis

Background

Multiple modes of cell death occur during the development of sepsis. Among these patterns, cuproptosis has recently been identified as a regulated form of cell death. However, its impact on the onset and progression of sepsis remains unclear.

Method

We screened a dataset of gene expression profiles from patients with sepsis using the GEO database. Survival analysis was performed to analyze the relationship between cuproptosis-related genes (CRGs) and prognosis. Hub genes were identified through univariate Cox regression analysis. The diagnostic value of hub genes in sepsis was tested in both training sets (GSE65682) and validation sets (GSE134347). To examine the association between hub genes and immune cells, single-sample gene set enrichment analysis (ssGSEA) and Pearson correlation analysis were employed. Additionally, the CRGs were validated in a septic mouse model using real-time quantitative PCR (qRT-PCR) and immunohistochemistry (IHC).

Results

In sepsis, most CRGs were upregulated, with only DLD and MTF1 downregulated. High expression of three genes (GLE, LIAS, and PDHB) was associated with better prognosis, but only two hub genes (LIAS, PDHB) reached statistical significance. The receiver operating characteristic (ROC) analysis for diagnosing sepsis showed LIAS had a range of 0.793-0.906, while PDHB achieved values of 0.882 and 0.975 in the training and validation sets, respectively. ssGSEA analysis revealed a lower number of immune cells in the sepsis group, and there was a correlation between immune cell population and CRGs (LIAS, PDHB). Analysis in the septic mouse model demonstrated no significant difference in mRNA expression levels and IHC staining between LIAS and PDHB in heart and liver tissues, but up-regulation was observed in lung tissues. Furthermore, the mRNA expression levels and IHC staining of LIAS and PDHB were down-regulated in renal tissues.

Conclusions

Cuproptosis is emerging as a significant factor in the development of sepsis. LIAS and PDHB, identified as potential diagnostic biomarkers for cuproptosis-associated sepsis, are believed to play crucial roles in the initiation and progression of cuproptosis-induced sepsis.