Inhibition Of Apoptosis Research Articles

Docetaxel-Induced Cell Death Is Regulated by a Fatty Acid-Binding Protein 12-Slug-Survivin Pathway in Prostate Cancer Cells.

Chemotherapy is an important treatment option for advanced prostate cancer, especially for metastatic prostate cancer (PCa). Resistance to first-line chemotherapeutic drugs such as docetaxel often accompanies prostate cancer progression. Attempts to overcome resistance to docetaxel by combining docetaxel with other biological agents have been mostly unsuccessful. A better understanding of the mechanisms underlying docetaxel resistance may provide new avenues for the treatment of advanced PCa. We have previously found that the fatty acid-binding protein 12 (FABP12)-PPARγ pathway modulates lipid-related bioenergetics and PCa metastatic transformation through induction of Slug, a master driver of epithelial-to-mesenchymal transition (EMT). Here, we report that the FABP12-Slug axis also underlies chemoresistance in PCa cells. Cell sensitivity to docetaxel is markedly suppressed in FABP12-expressing cells, along with induction of Survivin, a typical apoptosis inhibitor, and inhibition of cleaved PARP, a hallmark of programmed cell death. Importantly, Slug depletion down-regulates Survivin and restores cell sensitivity to docetaxel in FABP12-expressing cells. Finally, we also show that high levels of Survivin are associated with poor prognosis in PCa patients, with FABP12 status determining its prognostic significance. Our research identifies a FABP12-Slug-Survivin pathway driving docetaxel resistance in PCa cells, suggesting that targeting FABP12 may be a precision approach to improve chemodrug efficacy and curb metastatic progression in PCa.

Downregulation of CIAPIN1 regulates the proliferation, migration and glycolysis of breast cancer cells via inhibition of STAT3 pathway

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) is a protein that regulates apoptosis and programmed cell death. This research aims to evaluate its potential role in inhibiting breast cancer cell proliferation, migration, and glycolysis and uncover its underlying molecular mechanism. We collected breast cancer tissue samples from eight patients between January 2019 and June 2023 in our Hospital to analyse CIAPIN1 expression. We transfected human breast cancer cell lines (MCF7, MDA-MB-231, MDA-MB-453, and MDA-MB-468) with siRNA of CIAPIN1. Finally, we determined protein expression using RT-qPCR and Western blotting. CIAPIN1 expression was elevated in both breast cancer tissue and serum. Overexpression of CIAPIN1 detected in the breast cancer cell lines MCF7 and MDA-MB-468. In addition, CIAPIN1 overexpression increased cell proliferation and migration rate. CIAPIN1 downregulation suppressed cell proliferation while elevated cellular apoptosis, reactive oxygen species (ROS) production and oxidative stress in breast cancer cells. Moreover, CIAPIN1 inhibition remarkably suppressed pyruvate, lactate and adenosine triphosphate (ATP) production and reduced the pyruvate kinase M2 (PKM2) protein expression and phosphorylation of signal transducer and activator of transcription 3 (STAT3) in breast cancer cells. Downregulation of CIAPIN1 suppresses cell proliferation, migration and glycolysis capacity in breast cancer cells by inhibiting the STAT3/PKM2 pathway.

Self-Assembly Hypoxic and ROS Dual Response Nano Prodrug as a New Therapeutic Approach for Glaucoma Treatments.

Glaucoma is an irreversible blinding eye disease characterized by retinal ganglion cell (RGC) death.Previous studies have demonstrated that protecting mitochondria and activating the CaMKII/CREB signaling pathway can effectively protect RGC and axon. However, currently treatments are often unsatisfactory, and the pathogenesis of glaucoma requires further elucidation. In this study, a ROS-responsive dual drug conjugate (OLN monomer) is first designed that simultaneously bonds nicotinamide and oleic acid. The conjugate self-assembled into nanoparticles (uhOLN-NPs) through the aggregation of multiple micelles and possesses ROS scavenging capability. Then, a polymer with a hypoxic response function is designed, which encapsulates uhOLN-NPs to form nanoparticles with hypoxic and ROS responses (HOLN-NPs). Under hypoxia in RGCs, the azo bond of HOLN-NPs breaks and releases uhOLN-NPs. Meanwhile, under high ROS conditions, the thioketone bond broke, leading to the dissociation of nano-prodrug. The released nicotinamide and oleic acid co-scavenge ROS and activate the CaMKII/CREB pathway, protecting mitochondria in RGCs. HOLN-NPs exhibit a significantly superior protective effect on R28 cells in glutamate models of glaucoma. The accumulation of HOLN-NPs in retinal RGCs lead to significant inhibition of RGC apoptosis and axonal damage in vivo. Notably, HOLN-NPs provide a new therapeutic approach for patients with neurodegenerative disease.

Antiapoptotic and antinociceptive effects of Achillea millefolium L. aqueous extract in rats with experimental painful diabetic neuropathy.

Neuropathy is one of the common complications of diabetes mellitus. This study aimed to determine the analgesic and antiapoptotic effects of the aqueous extract of Achillea millefolium L. (Ach) in rats with experimental painful diabetic neuropathy by behavioral and molecular procedures. Thirty male Wistar rats were divided into 5 groups including control, diabetes + saline, and diabetes + Ach extract (doses of 150, 300, and 600 mg/kg/day for 3 weeks, orally). A tail-flick test was performed to assess the pain threshold in different groups. Western blotting test was used to evaluate the apoptotic (Bax, Bcl2, cleaved caspase-3, and cytochrome-c) and inflammatory (TNF-α and NF-kB) protein factors in the lumbar portion of the spinal cord tissue. Also, commercial assay kits were used to evaluate oxidative stress factors (MDA, GPx, and SOD enzyme activity) in the lumbar portion of the spinal cord tissue. Results showed that administering Ach extract at the doses of 300 and 600 mg/kg/day significantly increased the nociception threshold in treated diabetic animals compared to untreated diabetic animals. Moreover, the treatment of diabetic animals with Ach extract (300 and 600 mg/kg/day) significantly reduced the oxidative stress, inflammation, and apoptosis biochemical indicators in the lumbar spinal cord tissue compared to the untreated diabetic group. The findings showed that Ach extract has neuroprotective and anti-nociceptive effects in rats with diabetic neuropathy. The effects can be due to the inhibition of oxidative stress, inflammation, and apoptosis in the spinal cord tissue.

Shenqi Sanjie Granules induce Hmox1-mediated ferroptosis to inhibit colorectal cancer

BackgroundBecause adverse reactions or drug resistance are often found after current chemotherapies for metastatic colorectal cancer (mCRC), new treatments are still in demand. Shenqi Sanjie Granules (SSG), an antitumor compound preparation of traditional Chinese medicine, has been recognized for its ability in clinical practice of oncotherapy. Nevertheless, the precise effects of SSG in colorectal cancer (CRC) and underlying mechanisms through which SSG inhibits CRC remain uncertain. The current study aimed to evaluate the anti-CRC activity of the Chinese herbal compound preparation SSG and investigate the underlying mechanisms of action. Materials and methodsInitially, nine distinct cancer cell lines, including five CRC cell lines, one breast cancer cell line, two lung adenocarcinoma cell lines and one cervical cancer cell line, were used to evaluate the antitumor activity of SSG, and the mouse CRC cell line CT26 were used for further research. In vitro experiments utilizing diverse assays were conducted to assess the inhibitory effects of the SSG on CT26. Furthermore, subcutaneous syngeneic mouse model and AOM (azoxymethane)/DSS (dextran sodium sulfate) induced in-situ colitis-related mouse CRC model were used to evaluate the antitumor potential and biotoxicity of SSG in vivo. To elucidate the underlying molecular mechanisms, transcriptome sequencing and network pharmacology analysis were performed. Meanwhile, verification is carried out with quantitative real-time PCR (qRT-PCR) and flow cytometry (FCM) analysis. ResultsOur in vitro inhibition study showed that SSG could effectively inhibit CRC cell line CT26 growth and metastasis, and induce cell death. Neither of apoptosis inhibitor, necroptosis inhibitor, ferroptosis inhibitor, but the combination of the three diminished SSG-induced cell death, suggesting that multiple cell death pathways were involved. Both the syngeneic CRC model and the in-situ CRC model indicated SSG inhibited CRC in vivo with few toxic side effects. Further mechanistic study suggested SSG treatment activated the ferroptosis pathway, particularly mediated by Hmox1, which was upregulated scores of times. Network pharmacology analysis indicated that the active ingredients of SSG, including Quercetin, Luteolin and Kaempferol were potential components directly upregulated Hmox1 expression. ConclusionsCollectively, our findings indicate that the administration of SSG has the potential to inhibit CRC both in vitro and in vivo. The mechanism by which this compound preparation exerts its action is, at least partly, the induction of ferroptosis through upregulating Hmox-1 by its three active ingredients Quercetin, Luteolin and Kaempferol.

Melastoma dodecandrum lour. Protects against cerebral ischemia–reperfusion injury by ameliorating oxidative stress and endoplasmic reticulum stress

Ethnopharmacological relevanceMelastoma dodecandrum Lour. (MD), a traditional Chinese medicine used by the She ethnic group, has been used to treat cerebral ischemia-reperfusion (CIR) injury due to its efficacy in promoting blood circulation and removing blood stasiss; however, the therapeutic effects and mechanisms of MD in treating CIR injury remain unclear. AimTo investigate the protective effects of MD on CIR injury, in addition to its impact on oxidative stress, endoplasmic reticulum (ER) stress, and cell apoptosis. Materials and methodsThe research was conducted using both cell experiments and animal experiments. The CCK-8 method, immunofluorescence staining, and flow cytometry were used to analyze the effects of MD-containing serum on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cell viability, reactive oxygen species (ROS) clearance, anti-inflammatory, neuroprotection and inhibition of apoptosis. Furthermore, 2,3,5-Triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, Nissl staining, and immunohistochemistry were used to detect infarct size, pathological changes, Nissl corpuscula and neuronal protein expression in middle cerebral artery occlusion (MCAO) rats. Polymerase chain reaction and Western Blotting were conducted in cell and animal experiments to detect the expression levels of ER stress-related genes and proteins. ResultsThe MD extract enhanced the viability of PC12 cells under OGD/R modeling, reduced ROS and IL-6 levels, increased MBP levels, and inhibited cell apoptosis. Furthermore, MD improved the infarct area in MCAO rats, increased the number of Nissl bodies, and regulated neuronal protein levels including Microtubule-Associated Protein 2 (MAP-2), Myelin Basic Protein (MBP), Glial Fibrillary Acidic Protein (GFAP), and Neurofilament 200 (NF200). Additionally, MD could regulate the expression levels of oxidative stress proteins malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT). Both cell and animal experiments demonstrated that MD could inhibit ER stress-related proteins (GRP78, ATF4, ATF6, CHOP) and reduce cell apoptosis. ConclusionThis study confirmed that the therapeutic mechanism of the MD extract on CIR injury was via the inhibition of oxidative stress and the ER stress pathway, in addition to the inhibition of apoptosis.

Exploring the Role of CBX3 as a Potential Therapeutic Target in Lung Cancer.

Epigenetic changes regulate gene expression through histone modifications, chromatin remodeling, and protein translation of these modifications. The PRC1 and PRC2 complexes shape gene repression via histone modifications. Specifically, the CBX protein family aids PRC1 recruitment to chromatin, impacting the progressive multistep process driving chromatin silencing. Among family members, CBX3 is a complex protein involved in aberrant epigenetic mechanisms that drive lung cancer progression. CBX3 promotes lung tumorigenesis by interacting with key pathways such as PI3K/AKT, Ras/KRAS, Wnt/β-catenin, MAPK, Notch, and p53, leading to increased proliferation, inhibition of apoptosis, and enhanced resistance to therapy. Given our current lack of knowledge, additional research is required to uncover the intricate mechanisms underlying CBX3 activity, as well as its involvement in molecular pathways and its potential biomarker evaluation. Specifically, the dissimilar roles of CBX3 could be reexamined to gain a greater insight into lung cancer pathogenesis. This review aims to provide a clear overview of the context-related molecular profile of CBX3, which could be useful for addressing clinical challenges and developing novel targeted therapies based on personalized medicine.

Expression of Concern: Atorvastatin ameliorates early brain injury through inhibition of apoptosis and ER stress in a rat model of subarachnoid hemorrhage.

Expression of Concern: Atorvastatin ameliorates early brain injury through inhibition of apoptosis and ER stress in a rat model of subarachnoid hemorrhage.

Enzyme-Mediated Duplex Exponential Amplification: A New Platform for Rapid Screening of <i>Hylurgus ligniperda</i>

As the world's second largest timber importer, wood demand in China has been growing extremely rapidly, leading to an increase of 163% from 2009 to 2018. The plant quarantine pest <i>H. ligniperda Fabricius, 1787</i> is an invasive species frequently intercepted at ports. <i>H. ligniperda</i> causes damage mainly to pine and spruce. To improve the efficiency of on-site inspection and the efficacy of early detection, tight quarantine in ports, time-effective identification, and a national surveillance program for high-risk invasive bark beetles are in urgent need. In this study, a simple, fast and accurate classification method for <i>H. ligniperda </i>is established based on the enzyme-mediated duplex exponential amplification (EmDEA) technique. Partial region from <i>inhibitor of apoptosis 2</i> (<I>IAP2)</I> gene was selected as the target and 6 primer/probe combinations were designed. Through selection, the combination of 3-HY-F3, 3-HY-R2 and 3-HY-RNA5 was chosen as the final primer-probe set, as it showed the lowest Ct with highest final fluorescence signal. Method validation and specificity test using 6 other beetle species living on coniferous wood showed that this method is result reliable and specific. Through parameter analysis with positive plasmid, the detection limit was calculated to be 13.6 copies/μL (9×10<sup>-7</sup> ng DNA/ reaction), much higher than conventional molecular methods such as PCR. The whole process including isothermal amplification, data analysis, and result output can be finished in 30 min, which is highly time-effective. Besides, the operation is simple and little training is needed for non-professionals. The application prospects of this rapid screening system include customs screening in ports, wild survey in non-lab situations and early warning system development. The new analysis platform EmDEA, can also be implemented in rapid detection and identification of other forestry pests.

25-Hydroxycholesterol induces oxidative stress, leading to apoptosis and ferroptosis in extravillous trophoblasts

25-hydroxycholesterol (25HC) is an oxysterol derived from cholesterol and plays a role in various cellular processes, such as lipid metabolism, inflammatory responses, and cell survival. Extravillous trophoblasts (EVTs) are a major cell type found in the placenta, which are highly energetic cells with proliferative and invasive properties. EVT dysfunction can lead to pregnancy complications, including preeclampsia and intrauterine growth restriction. This study investigated the effects and underlying mechanisms of action of 25HC on EVT proliferation. Swan 71 cells, an EVT cell line, were treated with different concentrations of 25HC. Next, cell proliferation was assessed. The mitochondrial reactive oxygen species (mtROS), mitochondrial membrane potentials (MMPs), lipid peroxidation (LPO), and glutathione (GSH) levels were measured. Apoptosis, ferroptosis, and autophagy were evaluated by western blotting and flow cytometry. The results revealed that 25HC significantly inhibited proliferation and decreased the metabolic activity of EVTs. Moreover, 25HC caused oxidative stress by altering mtROS, LPO, MMPs, and GSH levels. Additionally, 25HC induces apoptosis, ferroptosis, and autophagy through the modulation of relevant protein levels. Interestingly, pretreatment with Z-VAD-FMK, an apoptosis inhibitor, and ferrostatin-1, a ferroptosis inhibitor, partially restored the effects of 25HC on cell proliferation, oxidative stress, and cell death. In summary, our findings suggest that 25HC treatment inhibits EVT proliferation and triggers apoptosis, ferroptosis, and autophagy, which are attributable to oxidative stress.

PDCD4 interacting with PIK3CB and CTSZ promotes the apoptosis of multiple myeloma cells.

The role of programmed cell death 4 (PDCD4) in multiple myeloma (MM) development remains unknown. Here, we investigated its role and action mechanism in MM. Bioinformatic analysis indicated that patients with MM and high PDCD4 expression had higher overall survival than those with low PDCD4 expression. PDCD4 expression promoted MM cell apoptosis and inhibited their viability invitro and tumor growth invivo. RNA-binding protein immunoprecipitation sequencing analysis showed that PDCD4 is bound to the 5' UTR of the apoptosis-related genes PIK3CB, Cathepsin Z (CTSZ), and X-chromosome-linked apoptosis inhibitor (XIAP). PDCD4 knockdown reduced the cell apoptosis rate, which was rescued by adding PIK3CB, CTSZ, or XIAP inhibitors. Dual luciferase reporter assays confirmed the internal ribosome entry site (IRES) activity of the 5' UTRs of PIK3CB and CTSZ. An RNA pull-down assay confirmed binding of the 5' UTR of PIK3CB and CTSZ to PDCD4, identifying the specific binding fragments. PDCD4 is expected to promote MM cell apoptosis by binding to the IRES domain in the 5' UTR of PIK3CB and CTSZ and inhibiting their translation. Our findings suggest that PDCD4 plays an important role in MM development by regulating the expression of PIK3CB, CTSZ, and XIAP, and highlight new potential molecular targets for MM treatment.

FAM136A as a Diagnostic Biomarker in Esophageal Cancer: Insights into Immune Infiltration, m6A Modification, Alternative Splicing, Cuproptosis, and the ceRNA Network.

FAM136A promotes the progression and metastasis of various tumors. However, there are few studies on the role of FAM136A in esophageal cancer (ESCA). The TCGA, GTEx, and GEO databases are employed to analyze the expression of FAM136A in ESCA, and qPCR and TMA experiments are performed for validation. Enrichment analyzes are performed to investigate the association of FAM136A expression with immune features, m6A modification, alternative splicing, cuproptosis, and the ceRNA network via bioinformatics analysis. FAM136A is highly expressed in ESCA and correlated with lymph node metastasis and overall survival (OS). Bioinformatics analysis suggested that FAM136A may participate in the following processes to promote ESCA development and progression: 1) Promotion of mast cells infiltration to influence the ESCA immune microenvironment, 2) HNRNPC upregulation to regulate m6A modification, 3) ALYREF upregulation to increase the occurrence of retained intron (RI) events, 4) CDK5RAP1 upregulation to achieve inhibition of tumor cell apoptosis, and 5) promotion of ESCA progression through the lncRNA SNHG15/hsa-miR-29c-3p/FAM136A ceRNA network. FAM136A is a potential biomarker for ESCA diagnosis and treatment response evaluation, and the underlying mechanisms may be associated with immune infiltration, m6A modification, alternative splicing, cuproptosis, and the ceRNA regulatory network.

Clinical Value of lncRNA CASC19 in Myocardial Infarction and its Role in Myocardial Infarction-Induced Cardiomyocyte Apoptosis.

To explore the effect of long non-coding RNA cancer susceptibility 19 (lncRNA CASC19) on the activity, apoptosis, and oxidative stress response of cardiomyocytes, so as to assess the clinical relevance and molecular mechanism of CASC19 in myocardial infarction (MI). CASC19 level was determined by using real-time quantitative polymerase chain reaction (RT-qPCR). MI model was constructed using hypoxia induction, and rat cardiomyocytes H9c2 were divided into control group, MI group, MI small interference negative control (MI-si-NC) group, MI-si-CASC19 group, MI-si-CASC19+microRNA-NC (miR-NC) group, and MI-si-CASC19+miR-218-5p inhibitor group. Tetramethylazolium salt colorimetric method and flow cytometry were used to evaluate cell activity and apoptotic capacity. Cellular oxidative stress was evaluated using malondialdehyde and superoxide dismutase kits. The relationship between CASC19 and miR-218-5p was confirmed by using dual-luciferase activity assay. CASC19 levels were enhanced in MI patients and hypoxia-induced cardiomyocytes. Downregulating CASC19 promoted the proliferation, while suppressed apoptosis and oxidative stress in the MI cell model. Moreover, low expression of miR-218-5p reversed the promotion of proliferation and inhibition of apoptosis and oxidative stress in MI cell models by silencing CASC19. Briefly, CASC19 may serve as a diagnostic marker for MI by sponging miR-218-5p to inhibit apoptosis and oxidative stress in cardiomyocytes and promote cell survival.

Fluoride-Induced Alterations in the Pancreas of Mammals: A Meta-analysis.

This review explores the diverse effects of fluoride on pancreatic function, encompassing both in vitro and in vivo studies. Fluoride exposure induces notable alterations at the cellular and molecular levels, affecting pancreatic morphology, histology, and enzymatic activity. In vitro studies demonstrate significant inhibition of pancreatic α-amylase activity and apoptosis in pancreatic beta cells. In vivo investigations reveal structural abnormalities in pancreatic cells, including mitochondrial damage, vacuolation, and nuclear damage. Moreover, fluoride exposure disrupts antioxidant enzyme activity, exacerbating oxidative stress and lipid peroxidation. Changes in digestive enzyme activity, such as the inhibition of pancreatic lipase and α-amylase, further contribute to pancreatic dysfunction. Additionally, alterations in hormone secretion, notably insulin levels and disturbed glucose homeostasis, highlight the complex effects of fluoride on the pancreatic endocrine system. These findings underscore fluoride-induced pancreatic toxicity and highlight the need for a comprehensive understanding and mitigation strategies to safeguard pancreatic health.

Apoptosis-dependent head development during metamorphosis of the cnidarian Hydractinia symbiolongicarpus

Apoptosis is a regulated cell death that depends on caspases. It has mainly been studied as a mechanism for the removal of unwanted cells. However, apoptotic cells can induce fate or behavior changes of their neighbors and thereby participate in development. Here, we address the functions of apoptosis during metamorphosis of the cnidarian Hydractinia symbiolongicarpus. We describe the apoptotic profile during metamorphosis of the larva and identify Caspase3/7a, but no other executioner caspases, as essential for apoptosis in this context. Using pharmacological and genetic approaches, we find that apoptosis is required for normal head development. Inhibition of apoptosis resulted in defects in head morphogenesis. Neurogenesis was compromised in the body column of apoptosis-inhibited animals but there was no effect on the survival or proliferation of stem cells, suggesting that apoptosis is required for cellular commitment rather than for the maintenance of their progenitors. Differential transcriptomic analysis identifies TRAF genes as downregulated in apoptosis-inhibited larvae and functional experiments provide evidence that they are essential for head development. Finally, we find no major role for apoptosis in head regeneration in this animal, in contrast to the significance of apoptosis in Hydra head regeneration.

Effect of acacetin on inhibition of apoptosis in Helicobacter pylori-infected gastric epithelial cell line.

Helicobacter pylori (H. pylori) infection can cause extensive apoptosis of gastric epithelial cells, serving as a critical catalyst in the progression from chronic gastritis, gastrointestinal metaplasia, and atypical gastric hyperplasia to gastric carcinoma. Prompt eradication of H. pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer. Acacetin, which has multifaceted pharmacological activities such as anti-cancer, anti-inflammatory, and antioxidative properties, has been extensively investigated across various domains. Nevertheless, the impact and underlying mechanisms of action of acacetin on H. pylori-infected gastric mucosal epithelial cells remain unclear. To explore the defensive effects of acacetin on apoptosis in H. pylori-infected GES-1 cells and to investigate the underlying mechanisms. GES-1 cells were treated with H. pylori and acacetin in vitro. Cell viability was assessed using the CCK-8 assay, cell mortality rate via lactate dehydrogenase assay, alterations in cell migration and healing capacities through the wound healing assay, rates of apoptosis via flow cytometry and TUNEL staining, and expression levels of apoptosis-associated proteins through western blot analysis. H. pylori infection led to decreased GES-1 cell viability, increased cell mortality, suppressed cell migration, increased rate of apoptosis, increased expressions of Bax and cle-caspase3, and decreased Bcl-2 expression. Conversely, acacetin treatment enhanced cell viability, mitigated apoptosis induced by H. pylori infection, and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3. Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H. pylori-infected GES-1 cells, thereby exerting a protective effect on gastric mucosal epithelial cells.

Pharmacological mechanisms by which baicalin ameliorates cardiovascular disease.

Baicalin is a flavonoid glycoside obtained from the dried root of Scutellaria baicalensis Georgi, which belongs to the Labiatae family. Accumulating evidence indicates that baicalin has favorable therapeutic effects on cardiovascular diseases. Previous studies have revealed the therapeutic effects of baicalin on atherosclerosis, myocardial ischemia/reperfusion injury, hypertension, and heart failure through anti-inflammatory, antioxidant, and lipid metabolism mechanisms. In recent years, some new ideas related to baicalin in ferroptosis, coagulation and fibrinolytic systems have been proposed, and new progress has been made in understanding the mechanism by which baicalin protects cardiomyocytes. However, many relevant underlying mechanisms remain unexplained, and much experimental data is lacking. Therefore, further research is needed to determine these mechanisms. In this review, we summarize the mechanisms of baicalin, which include its anti-inflammatory and antioxidant effects; inhibition of endothelial cell apoptosis; modulation of innate immunity; suppression of vascular smooth muscle cells proliferation, migration, and contraction; regulation of coagulation and fibrinolytic systems; inhibition of myocardial hypertrophy; prevention of myocardial fibrosis; and anti-apoptotic effects on cardiomyocytes.

No Time to Die: How Cytomegaloviruses Suppress Apoptosis, Necroptosis, and Pyroptosis.

Viruses are obligate intracellular pathogens as their replication depends on the metabolism of the host cell. The induction of cellular suicide, known as programmed cell death (PCD), has the potential to hinder viral replication and act as a first line of defense against viral pathogens. Apoptosis, necroptosis, and pyroptosis are three important PCD modalities. Different signaling pathways are involved in their execution, and they also differ in their ability to cause inflammation. Cytomegaloviruses (CMV), beta-herpesviruses with large double-stranded DNA genomes, encode a great variety of immune evasion genes, including several cell death suppressors. While CMV inhibitors of apoptosis and necroptosis have been known and studied for years, the first pyroptosis inhibitor has been identified and characterized only recently. Here, we describe how human and murine CMV interfere with apoptosis, necroptosis, and pyroptosis signaling pathways. We also discuss the importance of the different PCD forms and their viral inhibitors for the containment of viral replication and spread in vivo.

MAPK Signaling-Mediated RFNG Phosphorylation and Nuclear Translocation Restrain Oxaliplatin-Induced Apoptosis and Ferroptosis.

Chemotherapy resistance remains a major challenge in the treatment of colorectal cancer (CRC). Therefore, it is crucial to develop novel strategies to sensitize cancer cells to chemotherapy. Here, the fringe family is screened to determine their contribution to chemotherapy resistance in CRC. It is found that RFNG depletion significantly sensitizes cancer cells to oxaliplatin treatment. Mechanistically, chemotherapy-activated MAPK signaling induces ERK to phosphorylate RFNG Ser255 residue. Phosphorylated RFNG S255 (pS255) interacts with the nuclear importin proteins KPNA1/importin-α1 and KPNB1/importin-β1, leading to its translocation into the nucleus where it targets p53 and inhibits its phosphorylation by competitively inhibiting the binding of CHK2 to p53. Consequently, the expression of CDKN1A is decreased and that of SLC7A11 is increased, leading to the inhibition of apoptosis and ferroptosis. In contrast, phosphor-deficient RFNG S225A mutant showed increased apoptosis and ferroptosis, and exhibited a notable response to oxaliplatin chemotherapy both in vitro and in vivo. It is further revealed that patients with low RFNG pS255 exhibited significant sensitivity to oxaliplatin in a patient-derived xenograft (PDX) model. These findings highlight the crosstalk between the MAPK and p53 signaling pathways through RFNG, which mediates oxaliplatin resistance in CRC. Additionally, this study provides guidance for oxaliplatin treatment of CRC patients.

52 Ferroptosis Suppressor Protein 1 is a Potent and Targetable Inhibitor of Ferroptosis in Chromophobe Renal Cell

Abstract Background There are currently no proven therapies for metastatic or unresectable Chromophobe renal cell carcinoma (ChRCC). Ferroptosis is an iron-dependent form of cell death characterized by the peroxidation of membrane polyunsaturated fatty acids, leading to membrane damage and cell death. Glutathione, a potent cellular antioxidant, counters lipid peroxidation to prevent ferroptosis. Both reduced and oxidized glutathione are markedly elevated in ChRCC (PNAS, 2018). We have previously discovered that ChRCC is hypersensitive to ferroptotic cell death induced by the pharmacologic disruption of glutathione homeostasis via the cysteine transporter SLC7A11 or glutathione peroxidase (GPX4) inhibition (PNAS, 2022). Ferroptosis suppressor protein (FSP1) is a glutathione-independent suppressor of ferroptosis. FSP1’s role in ChRCC is unexplored. Methods Transcriptional data from DepMap (484 cell lines) and Cancer Therapeutics Response Portal (CTRP) (860 cell lines) were used to study genetic or pharmacologic inhibition of GPX4 and SLC7A11. Statistical analysis was performed in PRISM 10 using Mann-Whitney U and ANOVA tests. Statistical significance was defined as p < 0.05. Results DepMap data revealed that FSP1 is the top upregulated gene in cells resistant to RNAi inhibition of GPX4 (Achilles, DEMETER2) (Panel A). In CTRP data, FSP1 was the top upregulated gene in cells resistant to the GPX4 inhibitor RSL3 and the 19th most upregulated gene in cells resistant to the SCL7A11 inhibitor, Erastin (Panel B). In The Cancer Genomic Atlas (TCGA) KICH (ChRCC) dataset, FSP1 was 2-fold higher in ChRCC compared to normal kidney (mean RSEM = 818.9 vs 445.9, p-value <0.0001) (Panel C). In vitro studies of two ChRCC cell lines, UOK276 and RCJ-T2, revealed that while siRNA-mediated inhibition of GPX4 or FSP1 individually did not induce substantial cell death, their combination was synergistic and resulted in almost complete cell death (UOK276 mean viability 8% of siCTRL, p<0.0001; RCJ-T2 mean viability 13% of siCTRL, p<0.0001). Cell viability was completely rescued by the ferroptosis inhibitor ferrostatin-1 but not by the necroptosis inhibitor necrostatin-1 or the apoptosis inhibitor Z-Vad-FMK (Panel D). siRNA-mediated GPX4 knockdown combined with FSP1 pharmacologic inhibition (icFSP1 or FSEN1) induced extensive cell death (mean viability of siGPX4 + icFSP1 group = 21% of siCTRL + DMSO group, p<0.0001; mean viability of siGPX4 + FSEN1 group = 29% of siCTRL + DMSO group, p<0.0001) (Panel E). Combining RSL3 with FSEN1, or IKE with icFSP1, also demonstrated synergy, with the ChRCC cell lines showing increased overall sensitivity to these drug combinations compared to 786-0 cells (ccRCC-derived) and HeLa cells (Panel F). Snapshots from these experiments taken at [IKE] = 177nM and/or [icFSP1] = 20 mM for UOK276, and [RSL3] = 39.4 nM and/or [FSEN1] = 20 mM for RCJ-T2, show almost complete cell death when pharmacologic inhibitors of glutathione-dependent and -independent ferroptosis suppressors are combined, but no substantial cell death when each is used individually (7% and 10% viability in combination group compared to DMSO group for UOK276 and RCJ-T2 respectively, p<0.0001) (Panel G). Conclusions We show that in vitro genetic or pharmacologic inhibition of FSP1, a glutathione-independent inhibitor of ferroptosis, leads to ferroptosis in ChRCC-derived cells when combined with genetic or pharmacologic inhibition of the glutathione-dependent suppressors of ferroptosis GPX4 or SLC7A11.