Apoptotic cell death in disease-Current understanding of the NCCD 2023

Partial mitochondrial involvement in the antiproliferative and immunostimulatory effects of PT-112

PT-112 is a novel small molecule exhibiting promising clinical activity in patients with solid tumors. PT-112 kills malignant cells by inhibiting ribosome biogenesis while promoting the emission of immunostimulatory signals. Accordingly, PT-112 is an authentic immunogenic cell death (ICD) inducer and synergizes with immune checkpoint inhibitors in preclinical models of mammary and colorectal carcinoma. Moreover, PT-112 monotherapy has led to durable clinical responses, some of which persisting after treatment discontinuation. Mitochondrial outer membrane permeabilization (MOMP) regulates the cytotoxicity and immunogenicity of various anticancer agents. Here, we harnessed mouse mammary carcinoma TS/A cells to test whether genetic alterations affecting MOMP influence PT-112 activity. As previously demonstrated, PT-112 elicited robust antiproliferative and cytotoxic effects against TS/A cells, which were preceded by the ICD-associated exposure of calreticulin (CALR) on the cell surface, and accompanied by the release of HMGB1 in the culture supernatant. TS/A cells responding to PT-112 also exhibited eIF2α phosphorylation and cytosolic mtDNA accumulation, secreted type I IFN, and exposed MHC Class I molecules as well as the co-inhibitory ligand PD-L1 on their surface. Acute cytotoxicity and HMGB1 release caused by PT-112 in TS/A cells were influenced by MOMP competence. Conversely, PT-112 retained antiproliferative effects and its capacity to drive type I IFN secretion as well as CALR, MHC Class I and PD-L1 exposure on the cell surface irrespective of MOMP defects. These data indicate a partial involvement of MOMP in the mechanisms of action of PT-112, suggesting that PT-112 is active across various tumor types, including malignancies with MOMP defects.

Cell death and cancer: Metabolic interconnections

Recent findings in the cell death field have transformed our understanding of the interplay between metabolism and cell death in the context of cancer. In this review, we discuss the relationships between metabolism and the cell death pathways of apoptosis, necroptosis, pyroptosis, and ferroptosis, with a particular focus on recent advancements. We will also explore the regulation of metabolism by the BCL-2 family and the participation of oncometabolites in the regulation of cell death. Finally, we examine the emerging links between cell death signaling and cellular persistence. As we highlight in this review, the intersection of metabolic and cell death pathways has implications for cancer cell survival, treatment resistance, and the tumor microenvironment.

Deciphering molecular specificity in MCL-1/BAK interaction and its implications for designing potent MCL-1 inhibitors

The intricate interplay among BCL-2 family proteins governs mitochondrial apoptosis, with the anti-apoptotic protein MCL-1 primarily exerting its function by sequestering the pore-forming effector BAK. Understanding the MCL-1/BAK complex is pivotal for the sensitivity of cancer cells to BH3 mimetics, yet the precise molecular mechanism underlying their interaction remains elusive. Herein, we demonstrate that a canonical BH3 peptide from BAK inadequately binds to MCL-1 proteins, whereas an extended BAK-BH3 peptide with five C-terminal residues exhibits a remarkable 65-fold increase in affinity. By elucidating the complex structures of MCL-1 bound to these two BAK-BH3 peptides at 2.08 Å and 1.98 Å resolutions, we uncover their distinct binding specificities. Notably, MCL-1 engages in critical hydrophobic interactions with the extended BAK-BH3 peptide, particularly at an additional p5 sub-pocket, featuring a π-π stacking interaction between MCL-1 Phe319 and BAK Tyr89. Mutations within this p5 sub-pocket substantially disrupt the MCL-1/BAK protein-protein interaction. Furthermore, the p5 sub-pocket of MCL-1 significantly influences the efficacy of MCL-1 inhibitors. Overall, our findings elucidate the molecular specificity underlying MCL-1 binding to BAK and underscore the significance of the p5 hydrophobic sub-pocket in their high-affinity interaction, thus providing novel insights for the development of BH3 mimetics targeting the MCL-1/BAK interaction as potential therapeutics for cancer treatment.

Early-stage administration of hydroxytyrosol extends lifespan and delays aging in C. elegans

BACKGROUND

This study employs Caenorhabditis elegans (C. elegans) as a model organism to explore the anti-aging effects of hydroxytyrosol (HT) and its underlying mechanisms.

RESULTS

The findings reveal that HT significantly extends the lifespan of C. elegans while improving their functional performance (motility and pharyngeal function), and antioxidant capacity when administered on the first day of adulthood (D1). However, its efficacy diminishes when treatment begins on or after the third day of adulthood (D3). HT prolongs lifespan through a mechanism akin to that of skn-1 modulating the oxidative stress pathway.

CONCLUSIONS

This study suggests that the administration timing is an important factor for of anti-oxidation compounds to be effective in counteracting aging.

Deep transfer learning approach for automated cell death classification reveals novel ferroptosis-inducing agents in subsets of B-ALL

Ferroptosis is a recently described type of regulated necrotic cell death whose induction has anti-cancer therapeutic potential, especially in hematological malignancies. However, efforts to uncover novel ferroptosis-inducing therapeutics have been largely unsuccessful. In the current investigation, we classified brightfield microscopy images of tumor cells undergoing defined modes of cell death using deep transfer learning (DTL). The trained DTL network was subsequently combined with high-throughput pharmacological screening approaches using automated live cell imaging to identify novel ferroptosis-inducing functions of the polo-like kinase inhibitor volasertib. Secondary validation showed that subsets of B-cell acute lymphoblastic leukemia (B-ALL) cell lines, namely 697, NALM6, HAL01, REH and primary patient B-ALL samples were sensitive to ferroptosis induction by volasertib. This was accompanied by an upregulation of ferroptosis-related genes post-volasertib treatment in cell lines and patient samples. Importantly, using several leukemia models, we determined that volasertib delayed tumor growth and induced ferroptosis in vivo. Taken together, we have applied DTL to automated live-cell imaging in pharmacological screening to identify novel ferroptosis-inducing functions of a clinically relevant anti-cancer therapeutic.

Death-ision: the link between cellular resilience and cancer resistance to treatments

One of the key challenges in defeating advanced tumors is the ability of cancer cells to evade the selective pressure imposed by chemotherapy, targeted therapies, immunotherapy and cellular therapies. Both genetic and epigenetic alterations contribute to the development of resistance, allowing cancer cells to survive initially effective treatments. In this narration, we explore how genetic and epigenetic regulatory mechanisms influence the state of tumor cells and their responsiveness to different therapeutic strategies. We further propose that an altered balance between cell growth and cell death is a fundamental driver of drug resistance. Cell death programs exist in various forms, shaped by cell type, triggering factors, and microenvironmental conditions. These processes are governed by temporal and spatial constraints and appear to be more heterogeneous than previously understood. To capture the intricate interplay between death-inducing signals and survival mechanisms, we introduce the concept of Death-ision. This framework highlights the dynamic nature of cell death regulation, determining whether specific cancer cell clones evade or succumb to therapy. Building on this understanding offers promising strategies to counteract resistant clones and enhance therapeutic efficacy. For instance, combining DNMT inhibitors with immune checkpoint blockade may counteract YAP1-driven resistance or the use of transcriptional CDK inhibitors could prevent or overcome chemotherapy resistance. Death-ision aims to provide a deeper understanding of the diversity and evolution of cell death programs, not only at diagnosis but also throughout disease progression and treatment adaptation.

Impact of radiation therapy on the immunological tumor microenvironment

External beam radiation therapy (RT) is a cornerstone of modern cancer management, being utilized in both curative and palliative settings due to its safety, efficacy, and widespread availability. A primary biological effect of RT is DNA damage, which leads to significant cytostatic and cytotoxic effects. Importantly, malignant cells possess a limited capacity for DNA repair compared to normal cells, and when combined with irradiation techniques that minimize damage to healthy tissues, this creates an advantageous therapeutic window. However, the clinical effectiveness of RT also appears to involve both direct and indirect interactions between RT and non-transformed components of the tumoral ecosystem, particularly immune cells. In this review, we describe the molecular and cellular mechanisms by which irradiated cancer cells modify the immunological tumor microenvironment and how such changes ultimately impact tumor growth.

Caspases: structural and molecular mechanisms and functions in cell death, innate immunity, and disease

Caspases are critical regulators of cell death, development, innate immunity, host defense, and disease. Upon detection of pathogens, damage-associated molecular patterns, cytokines, or other homeostatic disruptions, innate immune sensors, such as NLRs, activate caspases to initiate distinct regulated cell death pathways, including non-lytic (apoptosis) and innate immune lytic (pyroptosis and PANoptosis) pathways. These cell death pathways are driven by specific caspases and distinguished by their unique molecular mechanisms, supramolecular complexes, and enzymatic properties. Traditionally, caspases are classified as either apoptotic (caspase-2, -3, -6, -7, -8, -9, and -10) or inflammatory (caspase-1, -4, -5, and -11). However, extensive data from the past decades have shown that apoptotic caspases can also drive lytic inflammatory cell death downstream of innate immune sensing and inflammatory responses, such as in the case of caspase-3, -6, -7, and -8. Therefore, more inclusive classification systems based on function, substrate specificity, or the presence of pro-domains have been proposed to better reflect the multifaceted roles of caspases. In this review, we categorize caspases into CARD-, DED-, and short/no pro-domain-containing groups and examine their critical functions in innate immunity and cell death, along with their structural and molecular mechanisms, including active site/exosite properties and substrates. Additionally, we highlight the emerging roles of caspases in cellular homeostasis and therapeutic targeting. Given the clinical relevance of caspases across multiple diseases, improved understanding of these proteins and their structure-function relationships is critical for developing effective treatment strategies.

Endoplasmic reticulum stress in acute pancreatitis: Exploring the molecular mechanisms and therapeutic targets

Acute pancreatitis (AP) is associated with multiple cellular mechanisms that trigger and or are triggered by the inflammatory injury and death of the acinar cells. One of the key mechanisms is the endoplasmic reticulum (ER) stress, which manifests as an accumulation of misfolded proteins within ER, an event that has proinflammatory and proapoptotic consequences. Hence, the degree of cell insult during AP could considerably depend on the signaling pathways that are upregulated during ER stress and its resulting dyshomeostasis such as C/EBP homologous protein (CHOP), cJUN NH2-terminal kinase (JNK), nuclear factor kappa B (NF-κB), and NOD-like receptor protein 3 (NLRP3) inflammasome. Exploring these molecular pathways is an interesting area for translational medicine as it may lead to identifying new therapeutic targets in AP. This review of the literature aims to shed light on the different roles of ER stress in the etiopathogenesis and pathogenesis of AP. Then, it specifically focuses on the therapeutic implications of ER stress in this context.

Pyroptosis: molecular mechanisms and roles in disease

Pyroptosis is a type of programmed necrosis triggered by the detection of pathogens or endogenous danger signals in the cytosol. Pyroptotic cells exhibit a swollen, enlarged morphology and ultimately undergo lysis, releasing their cytosolic contents - such as proteins, metabolites, and nucleic acids - into the extracellular space. These molecules can function as danger-associated molecular patterns (DAMPs), triggering inflammation when detected by neighboring cells. Mechanistically, pyroptosis is initiated by members of the gasdermin protein family, which were identified a decade ago as pore-forming executors of cell death. Mammalian gasdermins consist of a cytotoxic N-terminal domain, a flexible linker, and a C-terminal regulatory domain that binds to and inhibits the N-terminus. Proteolytic cleavage within the linker releases the N-terminal domain, enabling it to target various cellular membranes, including nuclear, mitochondrial, and plasma membranes, where it forms large transmembrane pores. Gasdermin pores in the plasma membrane disrupt the electrochemical gradient, leading to water influx and cell swelling. Their formation also activates the membrane protein ninjurin-1 (NINJ1), which oligomerizes to drive complete plasma membrane rupture and the release of large DAMPs. Since their discovery as pore-forming proteins, gasdermins have been linked to pyroptosis not only in host defense but also in various pathological conditions. This review explores the history of pyroptosis, recent insights into gasdermin activation, the cellular consequences of pore formation, and the physiological roles of pyroptosis.

Ferroptosis and Iron Homeostasis: Molecular Mechanisms and Neurodegenerative Disease Implications

Iron dysregulation has emerged as a pivotal factor in neurodegenerative pathologies, especially through its capacity to promote ferroptosis, a unique form of regulated cell death driven by iron-catalyzed lipid peroxidation. This review synthesizes current evidence on the molecular underpinnings of ferroptosis, focusing on how disruptions in iron homeostasis interact with key antioxidant defenses, such as the system Xc--glutathione-GPX4 axis, to tip neurons toward lethal oxidative damage. Building on these mechanistic foundations, we explore how ferroptosis intersects with hallmark pathologies in Alzheimer's disease (AD) and Parkinson's disease (PD) and examine how iron accumulation in vulnerable brain regions may fuel disease-specific protein aggregation and neurodegeneration. We further surveyed the distinct components of ferroptosis, highlighting the role of lipid peroxidation enzymes, mitochondrial dysfunction, and recently discovered parallel pathways that either exacerbate or mitigate neuronal death. Finally, we discuss how these insights open new avenues for neuroprotective strategies, including iron chelation and lipid peroxidation inhibitors. By highlighting open questions, this review seeks to clarify the current state of knowledge and proposes directions to harness ferroptosis modulation for disease intervention.

Unravelling the role of protein kinase R (PKR) in neurodegenerative disease: a review

Protein Kinase R is an essential regulator of many cell activities and belongs to one of the largest and most functionally complex gene families. These are found all over the body, and by adding phosphate groups to the substrate proteins, they regulate their activity and coordinate the action of almost all cellular processes. Recent research has illuminated the involvement of PKR in the pathogenesis of neurodegenerative disorders (NDs), thereby expanding our understanding of intricate molecular mechanisms underlying disease progression. Through their inhibition or activation, they hold potential therapeutic targets for the pathogenesis or protection of NDs. In the case of AD (AD), PKR contributes to the protection or elevation of Aβ accumulation, neuroinflammation, synaptic plasticity alterations, and neuronal excitability. Similarly, in Parkinson's disease (PD), PKR again has a dual role in dopaminergic neuronal loss, gene mutations, and mitochondrial dysfunction via various pathways. Notably, neuronal excitotoxicity, as well as genetic mutations, have been linked to ALS. In Huntington's disease (HD), PKR is associated with decreased or increased mutated genes, striatal neuron degeneration, neuroinflammation, and excitotoxicity. This review emphasizes strategies that target PKR for the treatment of neurodegenerative disorders. Doing so offers valuable insights that can guide future research endeavors and the development of innovative therapeutic approaches.

Cytosolic cytochrome c represses ferroptosis

The release of cytochrome c, somatic (CYCS) from mitochondria to the cytosol is an established trigger of caspase-dependent apoptosis. Here, we unveil an unexpected role for cytosolic CYCS in inhibiting ferroptosis-a form of oxidative cell death driven by uncontrolled lipid peroxidation. Mass spectrometry and site-directed mutagenesis revealed the existence of a cytosolic complex composed of inositol polyphosphate-4-phosphatase type I A (INPP4A) and CYCS. This CYCS-INPP4A complex is distinct from the CYCS-apoptotic peptidase activating factor 1 (APAF1)-caspase-9 apoptosome formed during mitochondrial apoptosis. CYCS boosts INPP4A activity, leading to increased formation of phosphatidylinositol-3-phosphate, which prevents phospholipid peroxidation and plasma membrane rupture, thus averting ferroptotic cell death. Unbiased screening led to the identification of the small-molecule compound 10A3, which disrupts the CYCS-INPP4A interaction. 10A3 sensitized cultured cells and tumors implanted in immunocompetent mice to ferroptosis. Collectively, these findings redefine our understanding of cytosolic CYCS complexes that govern diverse cell death pathways.

Cell death signaling in human erythron: erythrocytes lose the complexity of cell death machinery upon maturation

Over the recent years, our understanding of the cell death machinery of mature erythrocytes has been greatly expanded. It resulted in the discovery of several regulated cell death (RCD) pathways in red blood cells. Apoptosis (eryptosis) and necroptosis of erythrocytes share certain features with their counterparts in nucleated cells, but they are also critically different in particular details. In this review article, we summarize the cell death subroutines in the erythroid precursors (apoptosis, necroptosis, and ferroptosis) in comparison to mature erythrocytes (eryptosis and erythronecroptosis) to highlight the consequences of organelle clearance and associated loss of multiple components of the cell death machinery upon erythrocyte maturation. Recent advances in understanding the role of erythrocyte RCDs in health and disease have expanded potential clinical applications of these lethal subroutines, emphasizing their contribution to the development of anemia, microthrombosis, and endothelial dysfunction, as well as their role as diagnostic biomarkers and markers of erythrocyte storage-induced lesions. Fas signaling and the functional caspase-8/caspase-3 system are not indispensable for eryptosis, but might be retained in mature erythrocytes to mediate the crosstalk between both erythrocyte-associated RCDs. The ability of erythrocytes to switch between eryptosis and necroptosis suggests that their cell death is not a simple unregulated mechanical disintegration, but a tightly controlled process. This allows investigation of eventual pharmacological interventions aimed at individual cell death subroutines of erythrocytes.

Mitigating Diabetic Cardiomyopathy: The Synergistic Potential of Sea Buckthorn and Metformin Explored via Bioinformatics and Chemoinformatics

Diabetic cardiomyopathy (DCM), a critical complication of type 2 diabetes mellitus (T2DM), is marked by metabolic dysfunction, oxidative stress, and chronic inflammation, ultimately progressing to heart failure. This study investigated the synergistic therapeutic potential of Hippophae rhamnoides L. (sea buckthorn, SBU) extract and metformin in a mouse model of T2DM-induced DCM. T2DM was induced using a 45% high-fat-AGEs-enriched diet, followed by treatment with SBU, metformin, or their combination. Treatment effects were monitored through bioinformatic analysis, chemoinformatic prediction, behavioral testing, biochemical assays, histopathological evaluations and gene expression profiles. Based on bioinformatic analysis, we identified key hub genes involved in the diabetic cardiomyopathy including SERPINE1, NRG1, MYH11, PTH, NR4A2, NRF2, PGC1α, GPX4, ATF1, ASCL2, NOX1, NLRP3, CCK8, COX2, CCL2, PTGS2, EGFR, and oncostatin, which are pivotal in modulating the ferroptosis pathway. Furthermore, the expression of long non-coding RNAs (lncRNAs) NEAT1 and MALAT1, critical regulators of inflammation and cell death, was effectively downregulated, correlating with decreased levels of the pro-inflammatory marker oncostatin. The combined therapy significantly improved glucose regulation, reduced systemic inflammation and protected the heart from oxidative damage. Histopathological analysis revealed notable reductions in cardiac necrosis and fibrosis. Particularly, the combination therapy of SBU and metformin demonstrated a synergistic effect, surpassing the benefits of individual treatments in preventing cardiac damage. These findings highlight the potential of integrating SBU with metformin as a novel therapeutic strategy for managing DCM by targeting both metabolic and ferroptosis-related pathways. This dual intervention opens promising avenues for future clinical applications in diabetic heart disease management, offering a comprehensive approach to mitigating the progression of DCM.

Proinflammatory cytokines sensitise mesenchymal stromal cells to apoptosis

Mesenchymal stromal cells (MSCs) exert broad therapeutic effects across a range of inflammatory diseases. Their mechanism of action has largely been attributed to paracrine signalling, orchestrated by an array of factors produced by MSCs that are collectively termed the "secretome". Strategies to enhance the release of these soluble factors by pre-exposure to inflammatory cytokines, a concept known as "licensing", is thought to provide a means of enhancing MSC efficacy. Yet, recent evidence shows that intravenously infused MSCs entrapped within the lungs undergo apoptosis, and their subsequent clearance by host phagocytes is essential for their therapeutic efficacy. We therefore sought to clarify the mechanisms governing regulated cell death in MSCs and how exposure to inflammatory cytokines impacts this process. Our results show that MSCs are relatively resistant to cell death induced via the extrinsic pathway of apoptosis, as well as stimuli that induce necroptosis, a form of regulated inflammatory cell death. Instead, efficient killing of MSCs required triggering of the mitochondrial pathway of apoptosis, via inhibition of the pro-survival proteins MCL-1 and BCL-XL. Apoptotic bodies were readily released by MSCs during cell disassembly, a process that was inhibited in vitro and in vivo when the apoptotic effectors BAK and BAX were genetically deleted. Licensing of MSCs by pre-exposure to the inflammatory cytokines TNF and IFN-γ increased the sensitivity of MSCs to intrinsic apoptosis in vitro and accelerated their in vivo clearance by host cells within the lungs after intravenous infusion. Taken together, our study demonstrates that inflammatory "licensing" of MSCs facilitates cell death by increasing their sensitivity to triggers of the intrinsic pathway of apoptosis and accelerating the kinetics of apoptotic cell disassembly.

Cholesterol depletion suppresses thermal necrosis resistance by alleviating an increase in membrane fluidity

Thermally resistant cancer cells suppress the therapeutic effects of hyperthermia. However, the mechanism underlying the thermal resistance remains unclear. With the aim of enhancing the therapeutic effects of hyperthermia, we investigated the mechanism underlying thermal resistance. We found that heat shock-induced cell death can be classified into two types: late-phase apoptosis and early-phase necrosis. Cell death was suppressed in thermally resistant cells. In addition, heat-induced necrosis resistance correlated with plasma membrane fluidity, which was maintained by cholesterol. Depletion of cholesterol from cancer cells and tumor tissues enhanced the effect of hyperthermia under both in vivo and in vitro conditions. Hence, the findings demonstrate the usefulness of cholesterol as a marker for thermally resistant cancer cells. Furthermore, the combination of cholesterol depletion and hyperthermia may be a new therapeutic strategy for thermally resistant cancers.

The BCL2 family: from apoptosis mechanisms to new advances in targeted therapy

The B cell lymphoma 2 (BCL2) protein family critically controls apoptosis by regulating the release of cytochrome c from mitochondria. In this cutting-edge review, we summarize the basic biology regulating the BCL2 family including canonical and non-canonical functions, and highlight milestones from basic research to clinical applications in cancer and other pathophysiological conditions. We review laboratory and clinical development of BH3-mimetics as well as more recent approaches including proteolysis targeting chimeras (PROTACs), antibody-drug conjugates (ADCs) and tools targeting the BH4 domain of BCL2. The first BCL2-selective BH3-mimetic, venetoclax, showed remarkable efficacy with manageable toxicities and has transformed the treatment of several hematologic malignancies. Following its success, several chemically similar BCL2 inhibitors such as sonrotoclax and lisaftoclax are currently under clinical evaluation, alone and in combination. Genetic analysis highlights the importance of BCL-XL and MCL1 across different cancer types and the possible utility of BH3-mimetics targeting these proteins. However, the development of BH3-mimetics targeting BCL-XL or MCL1 has been more challenging, with on-target toxicities including thrombocytopenia for BCL-XL and cardiac toxicities for MCL1 inhibitors precluding clinical development. Tumor-specific BCL-XL or MCL1 inhibition may be achieved by novel targeting approaches using PROTACs or selective drug delivery strategies and would be transformational in many subtypes of malignancy. Taken together, we envision that the targeting of BCL2 proteins, while already a success story of translational research, may in the foreseeable future have broader clinical applicability and improve the treatment of multiple diseases.

Disruptions in cellular communication: Molecular interplay between glutamate/NMDA signalling and MAPK pathways in neurological disorders

Neurological disorders significantly impact the central nervous system, contributing to a growing public health crisis globally. The spectrum of these disorders includes neurodevelopmental and neurodegenerative diseases. This manuscript reviews the crucial roles of cellular signalling pathways in the pathophysiology of these conditions, focusing primarily on glutaminase/glutamate/NMDA receptor signalling, alongside the mitogen-activated protein kinase (MAPK) pathways-ERK1/2, C-JNK, and P38 MAPK. Activation of these pathways is often correlated with neuronal excitotoxicity, apoptosis, and inflammation, leading to many other pathological conditions such as traumatic brain injury, stroke, and brain tumor. The interplay between glutamate overstimulation and MAPK signalling exacerbates neurodegenerative processes, underscoring the complexity of cellular communication in maintaining neuronal health. Dysfunctional signalling alters synaptic plasticity and neuronal survival, contributing to cognitive impairments in various neurological diseases. The manuscript emphasizes the potential of targeting these signalling pathways for therapeutic interventions, promoting neuroprotection and reducing neuroinflammation. Incorporating insights from precision medicine and innovative drug delivery systems could enhance treatment efficacy. Overall, understanding the intricate mechanisms of these pathways is essential for developing effective strategies to mitigate the impact of neurological disorders and improve patient outcomes. This review highlights the necessity for further exploration into these signalling cascades to facilitate advancements in therapeutic approaches, ensuring better prognoses for individuals affected by neurological conditions.

Synergistic Effect of Ribitol and Shikonin Promotes Apoptosis in Breast Cancer Cells

The mortality rate of breast cancer remains high, despite remarkable advances in chemotherapy. Therefore, it is imperative to identify new treatment options. In the present study, we investigated whether the metabolite ribitol enhances the cytotoxic effect of shikonin against breast cancer in vitro. Here, we screened a panel of small molecules targeting energy metabolism against breast cancer. The results of the study revealed that ribitol enhances shikonin's growth-inhibitory effects, with significant synergy. A significant (p < 0.01) increase in the percentage (56%) of apoptotic cells was detected in the combined treatment group, compared to shikonin single-treatment group (38%), respectively. The combined ribitol and shikonin treatment led to significant arrest of cell proliferation (40%) (p < 0.01) compared to untreated cells, as well as the induction of apoptosis. This was associated with upregulation of p53 (p < 0.05) and downregulation of c-Myc (p < 0.01), Bcl-xL (p < 0.001), and Mcl-1 (p < 0.05). Metabolomic analysis supports the premise that inhibition of the Warburg effect is involved in shikonin-induced cell death, which is likely further enhanced by dysregulation of glycolysis and the tricarboxylic acid (TCA) cycle, afflicted by ribitol treatment. In conclusion, the present study demonstrates that the metabolite ribitol selectively enhances the cytotoxic effect mediated by shikonin against breast cancer in vitro.

The Interplay Between Autophagy and Apoptosis in the Mechanisms of Action of Stilbenes in Cancer Cells

Plant-based stilbenes are low-molecular-weight polyphenolic compounds that exhibit anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-diabetic, cardioprotective, neuroprotective, and anti-cancer activities. They are phytoalexins produced in diverse plant species in response to stress, such as fungal and bacterial infections or excessive UV irradiation. Plant-derived dietary products containing stilbenes are common components of the human diet. Stilbenes appear to be promising chemopreventive and chemotherapeutic agents. Accumulating evidence indicates that stilbenes are able to trigger both apoptotic and autophagic molecular pathways in many human cancer cell lines. Of note, the molecular crosstalk between autophagy and apoptosis under cellular stress conditions determines the cell fate. The autophagy and apoptosis relationship is complex and depends on the cellular context, e.g., cell type and cellular stress level. Apoptosis is a type of regulated cell death, whereas autophagy may act as a pro-survival or pro-death mechanism depending on the context. The interplay between autophagy and apoptosis may have an important impact on chemotherapy efficiency. This review focuses on the in vitro effects of stilbenes in different human cancer cell lines concerning the interplay between autophagy and apoptosis.

Hormone correction of dysfunctional metabolic gene expression in stem cell-derived liver tissue

The increase in metabolic dysfunction-associated steatotic liver disease (MASLD) and its progression to metabolic dysfunction-associated steatohepatitis (MASH) is a worldwide healthcare challenge. Heterogeneity between men and women in the prevalence and mechanisms of MASLD and MASH is related to differential sex hormone signalling within the liver, and declining hormone levels during aging. In this study we used biochemically characterised pluripotent stem cell derived 3D liver spheres to model the protective effects of testosterone and estrogen signalling on metabolic liver disease 'in the dish'. We identified sex steroid-dependent changes in gene expression which were protective against metabolic dysfunction, fibrosis, and advanced cirrhosis patterns of gene expression, providing new insight into the pathogenesis of MASLD and MASH, and highlighting new druggable targets. Additionally, we highlight gene targets for which drugs already exist for future translational studies.

3-(1H-pyrazole-1-yl/1H-1,2,4-triazole-1-yl)-N-propananilide Derivatives: Design, Synthesis and Neuroprotectivity Potential Against 6-OHDA Induced Neurotoxicity Model

Objectives

Excessive amounts of neuroapoptosis are the underlying cause of neurodegenerative diseases. Bax is a pro-apoptotic member of the B-cell lymphoma-2 family that activates caspases which are the members of the cysteine protease family that play a significant role in the initiation and execution phases of apoptosis. The aim of this study was to design and synthesize a group of N-propananilide derivatives bearing pyrazole or 1,2,4-triazole ring were designed and synthesized to analyze the neuroprotectivity potential against 6-hydroxy-dopamine (6-OHDA). Four compounds possessed protectivity at lower doses were subjected to further studies on caspase-3 and Bax pathway.

Materials and Methods

Designed compounds were synthesized by reacting 1H-pyrazole or 1H-1,2,4-triazole with propananilide intermediates in Dimethylformamide. The neuroprotective activity of the title compounds was analyzed against 6-OHDA-6-OHDA-induced neurotoxicity model. Then, caspase-3 and Bax levels were determined for the selected compounds by Western blot study.

Results

All twelve 3-(1H-pyrazole-1-yl/1H-1,2,4-triazole-1-yl)-N-propananilide derivatives possessed neuroprotectivity against the 6-OHDA-induced neurotoxicity model (p≤0.05, **p≤0.001, ***p≤0.005). Compounds 7, 10, 11, and 12 were found to be more active at lower doses. They were subjected to further studies and the results revealed that their protecting activity arose from the decreasing levels of Bax, one of the pro-apoptotic proteins, and c expression levels and caspase-3 proteins.

Conclusion

All designed and synthesized derivatives possessed neuroprotectivity against 6-OHDA-induced neurotoxicity in the SH-SY5Y cell line and compounds 7, 10, 11, and 12 revealed that their neuroprotectivity originated from the decreasing Bax expression levels and caspase-3 activation.

Recent advances in understanding the mechanisms by which sodium-glucose co-transporter type 2 inhibitors protect podocytes in diabetic nephropathy

BACKGROUND

Diabetes mellitus is associated with systemic damage across multiple organ systems, and an increasing number of patients are presenting with diabetic kidney disease as its initial manifestation. The onset and progression of diabetic nephropathy is closely associated with podocyte injury.

MAIN BODY

Sodium-glucose cotransporter type 2 (SGLT2) inhibitors, which can significantly reduce glucose levels as well as protecting against kidney damage, are therefore widely used for the clinical treatment of patients with diabetic kidney disease. An increasing body of research has revealed that the renal protective effect of SGLT2 inhibitors is primarily derived from their enhancement of podocyte autophagy and their inhibition of inflammation and podocyte apoptosis. Multiple signaling pathways are involved in these processes.

CONCLUSION

A deeper exploration of the renal protective effects of SGLT2 inhibitors and the underlying mechanisms will provide more solid theoretical support for their application in the prevention and treatment of diabetic kidney disease.

CeDaD-a novel assay for simultaneous tracking of cell death and division in a single population

The cell division cycle and the various forms of programmed cell death are interconnected. A prominent example is the tumor suppressor p53, which not only induces apoptosis but also plays an important role in the arrest of the cell cycle. Consequently, simultaneous analysis of cell division and cell death is frequently of significant interest in cell biology research. Traditionally, these processes require distinct assays, making concurrent analysis challenging. To address this, we present a novel combined assay, called CeDaD assay-Cell Death and Division assay-which allows for the simultaneous quantification of cell division and cell death within a single-cell population. This assay utilizes a straightforward flow cytometric approach, combining a staining based on carboxyfluorescein succinimidyl ester (CFSE) to monitor cell division with an annexin V-derived staining to assess the extent of cell death.

Extrinsic Apoptosis and Necroptosis in Telencephalic Development: A Single-Cell Mass Cytometry Study

Regulated cell death is integral to sculpting the developing brain, yet the relative contributions of extrinsic apoptosis and necroptosis remain unclear. Here, we leverage single-cell mass cytometry (CyTOF) to characterize the cellular landscape of the mouse telencephalon in wild-type (WT), RIPK3 knockout (RIPK3 KO), and RIPK3/Caspase-8 double knockout (DKO) mice. Strikingly, combined deletion of RIPK3 and Caspase-8 leads to a 12.6% increase in total cell count, challenging the prevailing notion that intrinsic apoptosis exclusively governs developmental cell elimination. Detailed subpopulation analysis reveals that DKO mice display selective enrichment of Tbr2⁺ intermediate progenitors and endothelial cells, underscoring distinct, cell type-specific roles for extrinsic apoptotic and necroptotic pathways. These findings provide a revised framework for understanding the coordinated regulation of cell number during telencephalic development and suggest potential mechanistic links to neurodevelopmental disorders characterized by aberrant cell death.

Parthanatos and apoptosis: unraveling their roles in cancer cell death and therapy resistance

Cell death is a fundamental process that needs to be maintained to balance cellular functions and prevent disease. There are several cell death pathways; however, apoptosis and parthanatos are the most prominent and have important roles in cancer biology. As an extremely well-regulated process, apoptosis removes damaged or abnormal cells via caspase activation and mitochondrial involvement. Unlike in the healthy cells, the loss of ability to induce apoptosis in cancer permits tumor cells to survive and multiply out of control and contribute to tumor progression and therapy resistance. On the contrary, parthanatos is a caspase-independent metabolic collapse driven by poly (ADP-ribose) polymerase 1 (PARP1) overactivation, translocation of apoptosis-inducing factor (AIF), and complete DNA damage. Several cancer models are involved with parthanatos. Deoxypodophyllotoxin (DPT) induces parthanatos in glioma cells by excessive ROS generation, PARP1 upregulation, and AIF nuclear translocation. Like in acute myeloid leukemia (AML), the cannabinoid derivative WIN-55 triggers parthanatos, and the effects can be reversed by PARP inhibitors such as olaparib. Developing cancer treatment strategies involving advanced cancer treatment strategies relies on the interplay between apoptosis and parthanatos. However, such apoptosis-based cancer therapies tend to develop resistance, so there is an urgent need to look into alternative pathways like parthanatos, which may not always trigger apoptosis. In overcoming apoptosis resistance, there is evidence that combining apoptosis-inducing agents, such as BH3 mimetics, with PARP inhibitors synergistically enhances cell death. Oxidative stress modulators have been found to promote the execution of parthanatic and apoptotic pathways and allow treatment. In this review, apoptosis and parthanatos are thoroughly compared at the molecular level, and their roles in cancer pathogenesis as related to cancer therapeutic potential are discussed. We incorporate recent findings to demonstrate that not only can parthanatos be used to manage therapy resistance and enhance cancer treatment via the combination of parthanatos and apoptosis but also that immunity and bone deposition can feasibly be employed against long-circulating cancer stem cells to treat diverse forms of metastatic cancers.

Synthesis of novel quinoline-thiazolobenzimidazolone hybrids as anticancer agents through caspase-dependent apoptosis

AIM

This work explores the synthesis of new bi-heterocyclic hybrid compounds based on quinoline ring and investigates their potential as anticancer agents.

MATERIALS & METHODS

The novel fused quinoline-thiazolo[3,2-a] benzimidazole-3(2 h)one hybrids were prepared by regioselective nucleophilic ring opening of the corresponding quinolinyl-oxiranes. In vitro cytotoxic activity was evaluated against human lung (A549) and gastric (AGS) cancer cell lines.

RESULTS

Global results showed that all tested compounds have promising inhibitory properties. Compounds 17 and 18 bearing two methoxy groups on the quinoline ring have exhibited remarkable and interesting activities. The investigation of the cell death process showed that these compounds activated a caspase-dependent apoptosis pathway. Results were further supported by molecular docking studies.

CONCLUSION

Both compounds exhibited good drug-like characteristics, which make them promising drug candidates.

Human health risks of heavy metals in water and vegetables: a deterministic and probabilistic study in Gilgit-Baltistan, Pakistan

There is a growing global concern about the presence of heavy metals in the environment due to their detrimental effects on human health. These metals are eminent poisons with carcinogenic features that can harm organs such as brain, kidney, lungs, etc. This study investigated the human health risks associated with toxic metals such as lead (Pb), nickel (Ni), cadmium (Cd), chromium (Cr), and copper (Cu) in drinking water and vegetable sources from Northern Areas, Gilgit-Baltistan, Pakistan. A total of 68 representative drinking water and the most commonly consumed green leafy vegetable samples were collected from Nagar and Hunza district. In this study, significant carcinogenic and non-carcinogenic risks were identified, particularly in children, using deterministic and Monte Carlo simulation methods in addition to spatial analysis, correlation, principal component analysis, and hierarchical clustering. Hazard quotient (HQ) oral > 1 for Cr, Ni, Cd, and Pb in the water and vegetables of the Hunza district; HQ > 1 for all heavy metals except for Mn in vegetables from Nagar in children. HQ > 1 for Mn and Cu in the water and vegetables of Hunza district, likewise Mn exceeded the HQ limit in the water and vegetables in adults from the Nagar region. Lifetime cancer risk (LCR) oral > 1E-4 for all toxic metals in children across all district samples. Similarly, Cd and Pb exceeded the LCR for adults from both districts. LCR_dermal > 1E-4 for Ni, Cr, and Pb in children of Hunza, suggesting more vulnerability to developing cancer over exposure to toxic metals. The level of HQ and LCR via inhalation, demonstrating no adverse health risks for children and adults. Furthermore, the Monte Carlo Simulation was applied to assess the probability of potential health risks, which indicated a significantly higher risk for children than for adults. These findings underline the urgent need for mitigation strategies to reduce heavy metal exposure in Nagar and Hunza regions.

Anastasis and Other Apoptosis-Related Prosurvival Pathways Call for a Paradigm Shift in Oncology: Significance of Deintensification in Treating Solid Tumors

What is apoptosis? The Nomenclature Committee on Cell Death and numerous other pioneering cancer/p53 biologists use the terms "apoptosis" and "cell death" interchangeably, disregard the mind-numbing complexity and heterogeneity that exists within a tumor (intratumor heterogeneity), disregard the contribution of polyploid giant cancer cells (PGCCs; the root causes of therapy resistance and relapse) to this heterogeneity, and then propose novel apoptosis-stimulating anticancer strategies. This is shocking for the following three reasons. First, clinical studies reported since the 1990s have revealed that increased apoptosis in solid tumors is associated with increased tumor diversity and poor prognosis. Second, we have known for years that dying (apoptotic) cancer cells release a panel of secretions (e.g., via phoenix rising and other pathways) that promote metastatic outgrowth. Third, over a decade ago, it was demonstrated that cancer cells can recover from late stages of apoptosis (after the formation of apoptotic bodies) via the homeostatic process of anastasis, resulting in the emergence of aggressive variants. The cell surface expression of CD24 has recently been reported to be preferentially enriched in recovered (anastatic) cancer cells that exhibit tumorigenic properties. These and related discoveries outlined herein call for a paradigm shift in oncology to focus on strategies that minimize the occurrence of treacherous apoptosis and other tumor-repopulating events (e.g., therapy-induced cancer cell dormancy and reactivation). They also raise an intriguing question: is deregulated anastasis (rather than evasion of apoptosis) a hallmark of cancer?

Immune genes involved in synaptic plasticity during early postnatal brain development contribute to post-stroke damage in the aging male rat brain

Stroke remains a leading cause of mortality and long-term disability worldwide, underscoring the urgent need to identify novel therapeutic targets to enhance brain circuitry repair and functional recovery. This study explores the concept of longevity assurance genes, which primarily function within genetic pathways responsible for repair and maintenance. These pathways encompass molecular and metabolic processes as well as organ- and system-level functions. To investigate this, we employed comparative transcriptomics to analyze gene expression patterns across three age groups with progressively decreasing brain plasticity: native postnatal day seven brains, and young and old naïve and lesioned rat male brains. Analysis revealed a highly symmetrical distribution of upregulated and downregulated genes in postnatal day 7 brains. In contrast, the gene expression profiles of post-stroke brains exhibited significant asymmetry, with a disproportionate increase in upregulated genes compared to downregulated ones in both young and old post-ischemic brains. Gene variance in juvenile brains predominantly reflected processes associated with brain plasticity (e.g., Dcx, Tubb2b, Dok4, Dpysl5) and cell proliferation (e.g., Bex4). Conversely, gene expression variance in young and aged post-stroke brains was largely linked to inflammatory pathways, driven by cytokine and chemokine signaling. Notably, several genes specifically upregulated in aged brains were identified, including Ehd4, Fut7, Lilrb4, Plek, Slfn13, Slc14a1, and Smpdl3a. Immune genes that facilitate synaptic plasticity during early postnatal brain development-through processes such as pruning and sprouting to establish new connections in response to external stimuli-also contribute to post-stroke damage, confirming the concept of antagonistic pleiotropy. Our results suggest that targeting age-related immune responses could be an effective therapeutic strategy for stroke recovery.

Intracellular metal ion-based chemistry for programmed cell death

Intracellular metal ions play essential roles in multiple physiological processes, including catalytic action, diverse cellular processes, intracellular signaling, and electron transfer. It is crucial to maintain intracellular metal ion homeostasis which is achieved by the subtle balance of storage and release of metal ions intracellularly along with the influx and efflux of metal ions at the interface of the cell membrane. Dysregulation of intracellular metal ions has been identified as a key mechanism in triggering programmed cell death (PCD). Despite the importance of metal ions in initiating PCD, the molecular mechanisms of intracellular metal ions within these processes are infrequently discussed. An in-depth understanding and review of the role of metal ions in triggering PCD may better uncover novel tools for cancer diagnosis and therapy. Specifically, the essential roles of calcium (Ca2+), iron (Fe2+/3+), copper (Cu+/2+), and zinc (Zn2+) ions in triggering PCD are primarily explored in this review, and other ions like manganese (Mn2+/3+/4+), cobalt (Co2+/3+) and magnesium ions (Mg2+) are briefly discussed. Further, this review elaborates on the underlying chemical mechanisms and summarizes these metal ions triggering PCD in cancer therapy. This review bridges chemistry, immunology, and biology to foster the rational regulation of metal ions to induce PCD for cancer therapy.

Death ligand receptor (DLR) signaling: Its non-apoptotic functions in cancer and the consequences of DLR-directed therapies

Death ligands (DLs), particularly tumor necrosis factor alpha (TNF-α), FAS ligand (FASL), and TNF-related apoptosis-inducing ligand (TRAIL), collectively termed TFT, are pivotal members of the TNF superfamily. While traditionally linked to apoptosis, TFT proteins have emerged as key regulators of various non-apoptotic processes. This review summarizes the non-apoptotic functions of TFT in cancer and explores the intricate crosstalk signaling pathways and their impact on nuclear factor kappa B (NF-κB) signaling, inflammation, and pro-tumorigenic function. It also highlights the potential connections and hurdles that exist in translating synthetic lethality strategies involving DLs into clinical applications. Lastly, it discusses the challenges and opportunities associated with TFT-targeted therapeutic strategies for both malignant and non-malignant diseases.

Sodium diethyldithiocarbamate trihydrate: an effective and selective compound for hematological malignancies

Myeloid leukemias and lymphomas are among the most common and well-studied hematological malignancies. However, due to the aggressiveness and rapid progression of certain subtypes, treating these diseases remains a challenge. Considering the promising results of diethyldithiocarbamates in preclinical and clinical oncology trials, this study aimed to investigate the potential of sodium diethyldithiocarbamate trihydrate (DETC) as a prototype for developing new drugs to treat hematological malignancies. In silico analysis using SwissADME was conducted to evaluate the physicochemical characteristics and pharmacokinetic properties of DETC. An in vitro investigation utilizing the MTT assay assessed the cytotoxic effects of DETC on neoplastic and non-neoplastic cell lines. Selectivity was determined using a selectivity index and a hemolysis assay, while the mechanism of cell death in neoplastic cell lines was examined through flow cytometry analysis of pro-apoptotic and anti-apoptotic protein levels. The results demonstrated that the physicochemical characteristics of DETC are suitable for oral administration. Furthermore, the compound showed promising cytotoxic activity against human myeloid leukemia (K562) and Burkitt's lymphoma (Daudi) cell lines, with high selectivity for neoplastic cells over non-neoplastic cells of the bone marrow microenvironment (HS-5 cell line). Moreover, hemolysis was observed only at very high concentrations. The cytotoxicity mechanism of DETC against both neoplastic cell lines involved cell cycle arrest and the production of reactive oxygen species. In K562 cells, cell death was induced via apoptosis. Additional experiments are needed to confirm the exact mechanism of cell death in Daudi Burkitt's lymphoma cells.

Donafenib activates the p53 signaling pathway in hepatocellular carcinoma, induces ferroptosis, and enhances cell apoptosis

Donafenib is an improved version of sorafenib in which deuterium is substituted into the drug's chemical structure, enhancing its stability and antitumor activity. Donafenib exhibits enhanced antitumor activity and better tolerance than sorafenib in preclinical and clinical studies. However, the specific mechanism of its effect on hepatocellular carcinoma has not been reported. Iron deposition is a cell death pattern caused by disturbances in iron metabolism. Apoptosis is a form of programmed cell death. They may interact with each other during cell death. This study mainly explores the potential mechanism of donafenib activating the p53 signaling pathway, inducing iron deposition, and enhancing cell apoptosis in hepatocellular carcinoma. Hepa1-6 and Huh7 cells were treated with various concentrations of donafenib. Scratch healing and pore migration tests were conducted. Analyze apoptosis through flow cytometry and TUNEL fluorescence labeling. RNA sequencing was conducted on both untreated and donafenib-treated Huh7 cells. The key proteins involved in ferroptosis (SLC7A11, GPX4) and apoptosis (caspase3, caspase8, Bax, Bcl-2, p53) were then evaluated using immunoblotting and immunohistochemical staining. Reactive oxygen species (ROS) levels in the cancer cells were measured. Donafenib treatment resulted in a dose-dependent decrease in the proliferation, migration, and invasion capabilities of cancer cells. There was an increase in apoptosis rates and ROS accumulation, and a reduction in tumor volume. The key proteins involved in ferroptosis and apoptosis underwent significant changes. Donafenib activates the p53 signaling pathway, induce ferroptosis, and enhance apoptosis, suggesting its potential as an effective therapeutic agent for HCC.

Investigating the protective effects of fluvoxamine against sepsis-related acute lung injury through antiapoptotic, anti-inflammatory, and anti-oxidant features in rats

Objectives

Acute lung injury (ALI) is characterized by severe hypoxia and alveolar damage, often caused by oxidative stress, endoplasmic reticulum stress (ERS), and apoptosis. Fluvoxamine (FLV), an antidepressant, has tissue-protective properties through various intracellular mechanisms. This study investigates the anti-inflammatory effects of FLV used as an antidepressant in a lipopolysaccharide (LPS)-induced ALI model.

Materials and Methods

Thirty-two female Wistar Albino rats aged 14-16 weeks and weighing 300-350 g, with 8 animals in each group, were divided into four groups: control, LPS, LPS+FLV, and FLV. After LPS administration, rats were euthanized, and histopathological analysis, immunohistochemistry for tumor necrosis factor-α (TNF-α) and caspase-3 (Cas-3), ELISA for oxidative stress markers, and PCR for CHOP, Cas-12, and Cas-9 gene expressions were conducted.

Results

In the LPS group, lung tissue damage, increased inflammatory cell infiltration, increased Cas-3 and TNF-α expressions, increased oxidative stress markers, and increased CHOP, Cas-9, and Cas-12 mRNA expressions were observed compared to the control group. FLV treatment in the LPS+FLV group significantly reversed these effects in the LPS group.

Conclusion

FLV exhibits protective effects against ALI by mitigating inflammation, ERS, and apoptosis via the CHOP/Cas-9/Cas-12 pathway. Further studies are needed to explore additional pathways and potential clinical applications of FLV.

Kinetic Assessment of HMGB1 Exodus by Automated Live Cell Imaging

The successful implementation of immune checkpoint inhibitors (ICIs) immunotherapy into clinical routine has underlined the importance of immunotherapy for the treatment of cancer. Nevertheless, benefits from ICI monotherapy remain limited to a subset of patients. The induction of immunogenic cell death (ICD) can prime tumors for subsequent ICI via the onset of adaptive immune responses leading to an infiltration of cytotoxic T lymphocytes. The nuclear and cellular nuclear release of high mobility group box 1 (HMGB1) is one of the hallmarks of ICD. Binding of HMGB1 to Toll-like receptor 4 (TLR4) expressed on dendritic cells plays a pivotal role in stimulating their maturation and antigen presentation, facilitating the onset of adaptive immunity. Here we describe microscopic assessments of HMGB1 release that can be applied to the screening of chemical compound libraries for novel ICD inducing agents. Thus, quantitative measurement of HMGB1 release kinetics can be useful for the discovery of new immuno-oncology drugs.

Decoding p53 tumor suppression: a crosstalk between genomic stability and epigenetic control?

Genomic instability, a hallmark of cancer, is a direct consequence of the inactivation of the tumor suppressor protein p53. Genetically modified mouse models and human tumor samples have revealed that p53 loss results in extensive chromosomal abnormalities, from copy number alterations to structural rearrangements. In this perspective article we explore the multifaceted relationship between p53, genomic stability, and epigenetic control, highlighting its significance in cancer biology. p53 emerges as a critical regulator of DNA repair mechanisms, influencing key components of repair pathways and directly participating in DNA repair processes. p53 role in genomic integrity however extends beyond its canonical functions. p53 influences also epigenetic landscape, where it modulates DNA methylation and histone modifications. This epigenetic control impacts the expression of genes involved in tumor suppression and oncogenesis. Notably, p53 ability to ensure cellular response to DNA demethylation contributes to the maintenance of genomic stability by preventing unscheduled transcription of repetitive non-coding genomic regions. This latter indicates a causative relationship between the control of epigenetic stability and the maintenance of genomic integrity in p53-mediated tumor suppression. Understanding these mechanisms offers promising avenues for innovative therapeutic strategies targeting epigenetic dysregulation in cancer and emphasizes the need for further research to unravel the complexities of this relationship. Ultimately, these insights hold the potential to transform cancer treatment and prevention strategies.

Immunogenicity of cell death and cancer immunotherapy with immune checkpoint inhibitors

While immunotherapy with immune checkpoint inhibitors (ICIs) has revolutionized the clinical management of various malignancies, a large fraction of patients are refractory to ICIs employed as standalone therapeutics, necessitating the development of combinatorial treatment strategies. Immunogenic cell death (ICD) inducers have attracted considerable interest as combinatorial partners for ICIs, at least in part owing to their ability to initiate a tumor-targeting adaptive immune response. However, compared with either approach alone, combinatorial regimens involving ICD inducers and ICIs have not always shown superior clinical activity. Here, we discuss accumulating evidence on the therapeutic interactions between ICD inducers and immunotherapy with ICIs in oncological settings, identify key factors that may explain discrepancies between preclinical and clinical findings, and propose strategies that address existing challenges to increase the efficacy of these combinations in patients with cancer.

Neuroglia in stroke

Stroke, ischemic or hemorrhagic, triggers a complex and coordinated glial response, which, to a large extent, defines the progression and outcome of this focal damage of the nervous tissue. Massive cell death in the infarction core results in a release of damage-associated molecular patterns, which, together with blood-borne factors entering the brain through either ruptured vessels or through compromised blood-brain barrier, trigger reactive gliosis. Microglia are the first to migrate toward the lesion, proliferate, and phagocytose cellular debris in and around the infarct core. Reactive astrogliosis occurs around the margins of the infarct core and is characterized by astrocytic proliferation, morphologic remodeling with loss of territorial domain segregation, and transcriptional reprogramming into wound repair astrocytes that form a periinfarct border that protects the healthy tissue and assists postlesional regeneration.

Unveiling the molecular profile of a prostate carcinoma: implications for personalized medicine

BACKGROUND

Prostate cancer is the most common diagnosed tumor and the fifth cancer related death among men in Europe. Although several genetic alterations such as ERG-TMPRSS2 fusion, MYC amplification, PTEN deletion and mutations in p53 and BRCA2 genes play a key role in the pathogenesis of prostate cancer, specific gene alteration signature that could distinguish indolent from aggressive prostate cancer or may aid in patient stratification for prognosis and/or clinical management of patients with prostate cancer is still missing. Therefore, here, by a multi-omics approach we describe a prostate cancer carrying the fusion of TMPRSS2 with ERG gene and deletion of 16q chromosome arm.

RESULTS

We have observed deletion of KDM6A gene, which may represent an additional genomic alteration to be considered for patient stratification. The cancer hallmarks gene signatures highlight intriguing molecular aspects that characterize the biology of this tumor by both a high hypoxia and immune infiltration scores. Moreover, our analysis showed a slight increase in the Tumoral Mutational Burden, as well as an over-expression of the immune checkpoints. The omics profiling integrating hypoxia, ROS and the anti-cancer immune response, optimizes therapeutic strategies and advances personalized care for prostate cancer patients.

CONCLUSION

The here data reported can lay the foundation for predicting a poor prognosis for the studied prostate cancer, as well as the possibility of targeted therapies based on the modulation of hypoxia, ROS, and the anti-cancer immune response.

Regulated Cell Death of Alveolar Macrophages in Acute Lung Inflammation: Current Knowledge and Perspectives

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a common and serious clinical lung disease characterized by extensive alveolar damage and inflammation leading to impaired gas exchange. Alveolar macrophages (AMs) maintain homeostatic properties and immune defenses in lung tissues. Several studies have reported that AMs are involved in and regulate ALI/ARDS onset and progression via different regulated cell death (RCD) programs, such as pyroptosis, apoptosis, autophagic cell death, and necroptosis. Notably, the effects of RCD in AMs in disease are complex and variable depending on the environment and stimuli. In this review, we provide a comprehensive perspective on how regulated AMs death impacts on ALI/ARDS and assess its potential in new therapeutic development. Additionally, we describe the crosstalk between different RCD types in ALI, and provide new perspectives for the treatment of ALI/ARDS and other severe lung diseases.

Succinate Regulates Endothelial Mitochondrial Function and Barrier Integrity

Endothelial dysfunction is a hallmark of several pathological conditions, including cancer, cardiovascular disease and inflammatory disorders. In these conditions, perturbed TCA cycle and subsequent succinate accumulation have been reported. The role of succinate as a regulator of immunological responses and inflammation is increasingly being recognized. Nevertheless, how endothelial cell function and phenotype are altered by elevated intracellular succinate has not been addressed yet. Thus, we employed numerous in vitro functional assays using primary HUVECs and diethyl succinate (DES), a cell membrane-permeable succinate analogue. An MTS assay 1 h post stimulation with DES suggested reduced metabolic activity in HUVECs. Concurrently, elevated production of ROS, including mitochondrial superoxide, and a reduction in mitochondrial membrane potential were observed. These findings were corroborated by Seahorse mito-stress testing, which revealed that DES acutely lowered the OCR, maximal respiration and ATP production. Given the link between mitochondrial stress and apoptosis, we examined important survival signalling pathways. DES transiently reduced ERK1/2 phosphorylation, a response that was followed by a skewed pro-apoptotic shift in the BAX to BCL2L1 gene expression ratio, which coincided with upregulating VEGF gene expression. This indicated an induction of mixed pro-apoptotic and pro-survival signals in the cell. However, the BAX/BCL-XL protein ratio was unchanged, suggesting that the cells did not commit themselves to apoptosis. An MTS assay, caspase 3/7 activity assay and annexin V/propidium iodide staining confirmed this finding. By contrast, stimulation with DES induced acute endothelial barrier permeability, forming intercellular gaps, altering cell size and associated actin filaments without affecting cell count. Notably, during overnight DES exposure gradual recovery of the endothelial barrier and cell sprouting was observed, alongside mitochondrial membrane potential restoration, albeit with sustained ROS production. COX-2 inhibition and EP4 receptor blockade hindered barrier restoration, implicating a role of COX-2/PGE2/EP4 signalling in this process. Interestingly, ascorbic acid pre-treatment prevented DES-induced acute barrier disruption independently from ROS modulation. In conclusion, succinate acts as a significant regulator of endothelial mitochondrial function and barrier integrity, a response that is counterbalanced by upregulated VEGF and prostaglandin production by the endothelial cells.

Gingival crevicular fluid Bax, Bcl-xl, interleukin-22, and transforming growth factor beta 1 levels in stage III periodontitis

BACKGROUND

Intrinsic apoptosis plays a critical role in immune defense and inflammation. Its dysregulation is involved in various chronic diseases. The B-cell lymphoma 2 (Bcl-2) family primarily mediates this mitochondrial pathway. This study aimed to investigate the proapoptotic Bcl-2-associated X protein (Bax) and antiapoptotic B-cell lymphoma-extra large (Bcl-xl) levels and their association with interleukin-22 (IL-22) and transforming growth factor beta 1 (TGF-β1) in the gingival crevicular fluid (GCF) of patients with periodontitis.

METHODS

A total of 75 systemically healthy nonsmokers were enrolled, of whom 23 had stage III periodontitis, 26 had gingivitis, and 26 were periodontally healthy. Whole-mouth clinical periodontal measurements were recorded. Bax, Bcl-xl, IL-22, and TGF-β1 levels in the GCF were determined by enzyme-linked immunosorbent assay (ELISA). Data were analyzed using nonparametric statistical tests.

RESULTS

The periodontitis group had significantly lower GCF Bax levels than the gingivitis group (p < 0.05). The periodontitis and gingivitis groups had higher GCF Bcl-xl levels than the periodontally healthy group (p < 0.05). GCF IL-22 levels were similar in all groups (p > 0.05). The periodontitis group had lower GCF TGF-β1 levels than the gingivitis and periodontally healthy groups (p < 0.05). The diseased groups had a lower GCF Bax/Bcl-xl ratio than the healthy controls (p < 0.05). IL-22 was positively correlated with Bax (p < 0.05).

CONCLUSIONS

This is the first study investigating GCF Bax and Bcl-xl levels in periodontal health and disease. Increased GCF Bcl-xl levels and a decreased Bax/Bcl-xl ratio in stage III periodontitis implicate that those apoptotic proteins may be involved in the pathogenesis of periodontal disease. Further studies are needed to enlighten the possible role of Bax and Bcl-xl and their association with IL-22 and TGF-β1 in periodontal diseases.

PLAIN LANGUAGE SUMMARY

A type of cell death called intrinsic apoptosis plays an important role in the body's defense system, and its dysregulation is linked to different human diseases. The B-cell lymphoma 2-associated X protein (Bax) and B-cell lymphoma-extra large (Bcl-xl) are apoptosis-related proteins, which promote and inhibit cell death, respectively. This study aimed to investigate Bax and Bcl-xl levels and their association with the signaling proteins interleukin-22 (IL-22) and transforming growth factor beta 1 (TGF-β1) in the gingival crevicular fluid (GCF), which accumulates around the necks of the teeth of patients suffering from gum diseases such as gingivitis and periodontitis. Clinical parameters were recorded and GCF was collected. Bax, Bcl-xl, IL-22, and TGF-β1 levels were measured by biochemical assay in periodontally healthy individuals who had healthy gums (n = 26) and patients with periodontitis (n = 23) and gingivitis (n = 26). Periodontitis patients had lower Bax levels than gingivitis patients. Periodontitis and gingivitis patients had higher Bcl-xl levels and a lower Bax/Bcl-xl ratio than periodontally healthy individuals. IL-22 was positively correlated with Bax. The present findings suggest that the apoptotic regulatory molecules may be involved in the development of gum diseases, highlighting the need for further research in this area.

Aluminum Concentration Is Associated with Tumor Mutational Burden and the Expression of Immune Response Biomarkers in Colorectal Cancers

Environmental pollution poses a significant risk to public health, as demonstrated by the bioaccumulation of aluminum (Al) in colorectal cancer (CRC). This study aimed to investigate the potential mutagenic effect of Al bioaccumulation in CRC samples, linking it to the alteration of key mediators of cancer progression, including immune response biomarkers. Aluminum levels in 20 CRC biopsy samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The results indicated that Al bioaccumulation occurred in 100% of the cases. A correlation between Al levels and tumor mutation burden was observed. Furthermore, RNA sequencing revealed a significant association between Al concentration and the expression of the immune checkpoint molecule CTLA-4. Although correlations with PD-1 and PD-L1 were not statistically significant, a trend was observed. Additionally, a correlation between Al levels and both the presence of myeloid cells and IFNγ expression was detected, linking Al exposure to inflammatory responses within the tumor microenvironment. These findings suggested that Al can play a role in CRC progression by promoting both genetic mutations and immune evasion. Given the ubiquitous presence of Al in industrial and consumer products, dietary sources, and environmental pollutants, these results underscored the need for stricter regulatory measures to control Al exposure.

Death by ribosome

Next to their essential role as protein production factories, ribosomes serve as molecular sensors of cell stress. Stalled and collided ribosomes trigger specific stress signaling, including the ribotoxic stress response (RSR). The RSR is initiated by the mitogen-activated protein (MAP)-3 kinase ZAKα in response to a plethora of translational aberrations, leading to activation of the stress-activated MAP kinases p38 and jun N-terminal kinase (JNK). Recent insights have highlighted an important role for the RSR pathway in triggering programmed cell death processes, including apoptosis and pyroptosis, in a broad range of physiologically relevant conditions. In this review, we summarize recent work on known links between programmed and accidental ribosome toxicity, RSR signaling, and cell death.

A Machine Learning Computational Framework Develops a Multiple Programmed Cell Death Index for Improving Clinical Outcomes in Bladder Cancer

Comprehensive action patterns of programmed cell death (PCD) in bladder cancer (BLCA) have not yet been thoroughly investigated. Here, we collected 19 different PCD patterns, including 1911 PCD-related genes, and developed a multiple programmed cell death index (MPCDI) based on a machine learning computational framework. We found that in the TCGA-BLCA training cohort and the independently validated GSE13507 cohort, the patients with high-MPCDI had a worse prognosis, whereas patients with low-MPCDI had a better prognosis. By combining clinical characteristics with the MPCDI, we constructed a nomogram. The C-index demonstrated that the nomogram was significantly more accurate compared to other variables, including MPCDI, age, gender, and clinical stage. The results of the decision curve analysis demonstrated that the nomogram had a better net clinical benefit compared to other clinical variables. Subsequently, we revealed the heterogeneity of BLCA patients, with significant differences in terms of overall immune infiltration abundance, immunotherapeutic response, and drug sensitivity in the two MPCDI groups. Encouragingly, the high-MPCDI patients showed better efficacy for commonly used chemotherapeutic drugs than the low-MPCDI patients, which suggests that MPCDI scores have a guiding role in chemotherapy for BLCA patients. In conclusion, the MPCDI developed and verified in this study is not only an emerging clinical classifier for BLCA patients, but it also serves as a reliable forecaster for both chemotherapy and immunotherapy, which can guide clinical management and clinical decision-making for BLCA patients.

Cytomegalovirus Biology Viewed Through a Cell Death Suppression Lens

Cytomegaloviruses, species-specific members of the betaherpesviruses, encode an impressive array of immune evasion strategies committed to the manipulation of the host immune system enabling these viruses to remain for life in a stand-off with host innate and adaptive immune mechanisms. Even though they are species-restricted, cytomegaloviruses are distributed across a wide range of different mammalian species in which they cause systemic infection involving many different cell types. Regulated, or programmed cell death has a recognized potential to eliminate infected cells prior to completion of viral replication and release of progeny. Cell death also naturally terminates replication during the final stages of replication. Over the past two decades, the host defense potential of known programmed cell death pathways (apoptosis, necroptosis, and pyroptosis), as well as a novel mitochondrial serine protease pathway have been defined through studies of cytomegalovirus-encoded cell death suppressors. Such virus-encoded inhibitors prevent virus-induced, cytokine-induced, and stress-induced death of infected cells while also moderating inflammation. By evading cell death and consequent inflammation as well as innate and adaptive immune clearance, cytomegaloviruses represent successful pathogens that become a critical disease threat when the host immune system is compromised. This review will discuss cell death programs acquired for mammalian host defense against cytomegaloviruses and enumerate the range of modulatory strategies this type of virus employs to balance host defense in favor of lifelong persistence.

Comparison of the Mitophagy and Apoptosis Related Gene Expressions in Waste Embryo Culture Medium of Female Infertility Types

Mitochondria is an important organelle for the oocyte-to-embryo transition in the early embryonic development period. The oocyte uses mitochondria functionally and its mitochondrial DNA (mtDNA) content as the main energy source in the embryo development at the preimplantation stage. The aim of this study is to compare mitophagic, apoptotic and humanin gene expressions from the culture medium fluid in which embryos are developed and monitored among normoresponder (NOR), polycystic ovary syndrome (PCOS), young and older patients with poor ovarian reserve (POR). The study groups consisted of infertile patients who applied to the Bahçeci Umut IVF Center as NOR (Control), PCOS, POR-Advanced (POR-A) and POR-Young (POR-Y). After the isolation of total RNA from the collected samples, MFN1, MFN2, PINK1, PARKIN, SMN1, SMN2, p53 and Humanin gene expressions were determined by Real Time-PCR. The average age of only the POR-A was determined to be higher than the NOR (p < 0.001). The MFN1, SMN2 (p < 0.05), Humanin and p53 gene expressions (p < 0.001) increased, while PINK1 gene expression decreased (p < 0.05), in the POR-Y compared to the NOR. A decrease in MFN2, PARKIN (p < 0.05) and PINK1 gene expressions was determined in the PCOS compared to the NOR (p < 0.001). Furthermore, a decrease was observed in MFN2, PINK1 (p < 0.001) and Humanin gene expressions compared to the NOR (p < 0.05). The current data are the first in the literature determining the apoptotic and mitophagic status of the oocyte. The current results prove that waste embryo culture fluid may provide a non-invasive profile for important cellular parameters such as mitochondrial dysfunction in female infertility. The evaluation of significant cellular parameters can be performed much earlier without any intervention into the embryo.