Upregulation Of P21 Research Articles

N-Glycoside of Indolo[2,3-a]pyrrolo[3,4-c]carbazole LCS1269 Exerts Anti-Glioblastoma Effects by G2 Cell Cycle Arrest and CDK1 Activity Modulation: Molecular Docking Studies, Biological Investigations, and ADMET Prediction

Background/Objectives: Indolo[2,3-a]pyrrolo[3,4-c]carbazole scaffold is successfully used as an efficient structural motif for the design and development of different antitumor agents. In this study, we investigated the anti-glioblastoma therapeutic potential of glycosylated indolocarbazole analog LCS1269 utilizing in vitro, in vivo, and in silico approaches. Methods: Cell viability was estimated by an MTT assay. The distribution of cell cycle phases was monitored using flow cytometry. Mitotic figures were visualized by fluorescence microscopy. Quantitative RT-PCR was used to evaluate the gene expression. The protein expression was assessed by Western blotting. Molecular docking and computational ADMET were approved for the probable protein target simulations and predicted pharmacological assessments, respectively. Results: Our findings clearly suggest that LCS1269 displayed a significant cytotoxic effect against diverse glioblastoma cell lines and patient-derived glioblastoma cultures as well as strongly suppressed xenograft growth in nude mice. LCS1269 exhibited more potent anti-proliferative activity toward glioblastoma cell lines and patient-derived glioblastoma cultures compared to conventional drug temozolomide. We further demonstrated that LCS1269 treatment caused the severe G2 phase arrest of cell cycle in a dose-dependent manner. Mechanistically, we proposed that LCS1269 could affect the CDK1 activity both by targeting active site of this enzyme and indirectly, in particular through the modulation of the Wee1/Myt1 and FOXM1/Plk1 signaling pathways, and via p21 up-regulation. LCS1269 also showed favorable pharmacological characteristics in in silico ADME prediction in comparison with staurosporine, rebeccamycin, and becatecarin as reference drugs. Conclusions: Further investigations of LCS1269 as an anti-glioblastoma medicinal agent could be very promising.

Cytotoxic effects of the standardized extract from Curcuma aromatica Salisb. rhizomes via induction of mitochondria-mediated caspase-dependent apoptotic pathway and p21-mediated G0/G1 cell cycle arrest on human gastric cancer AGS cells

ABSTRACT Curcuma aromatica Salisb. (C. aromatica) is one of the traditional herbs used to treat microbial infection, skin eruption, coronary heart disease, and other diseases, including cancer. However, the inhibitory effects and underlying mechanisms of action of C. aromatica on gastric cancer cells have not yet been fully elucidated. Our study aimed to examine the possible molecular mechanisms underlying the cytotoxic effects attributed to C. aromatica rhizome standardized extract against gastric cancer cells. The components of two major active compounds in C. aromatica rhizome extract were quantitatively analyzed using a simple and validated HPLC method. Cytotoxicity was determined in different gastric cancer and non-cancer cell lines. The biological activities of the extract targeting apoptosis and cell cycle-related genes on gastric cancer AGS cells were also investigated to elucidate the mechanisms relating to the anti-proliferative effect of C. aromatica rhizomes. The two major active compounds curdione and germacrone, in the C. aromatica extract were standardized to 0.64% and 1.12% w/w, respectively. The standardized extract (CAE) exerted cytotoxic effects on various cancer cells, whereas minimal effects at equivalent doses were noted for normal cells. CAE concentration-dependently suppressed growth of gastric cancer AGS cells via induction of apoptosis. Further studies revealed that CAE treatment disrupted mitochondrial membrane potential (ΔΨm), increased Bax/Bcl-2 ratio, and cytochrome c release, resulting in activation of caspase-9/-3 and subsequent cleavage of PARP. Further, the inhibitory effects of caspase-9/-3 expression by a synthetic pan-caspase inhibitor partially protected cells against apoptosis following CAE treatment. In addition, CAE significantly promoted cell death in AGS cells via an accumulation of cells in the G0/G1 phase. This effect was associated with upregulation of the CDK inhibitor p21 and downregulation of cyclin D1, cyclin E, CDK4, and CDK2 expression. Our data indicated that CAE exerted anti-proliferative activity by activating the mitochondria-mediated caspase-dependent apoptotic pathway and arresting the p21-mediated G0/G1 cell cycle on human gastric cancer AGS cells.

Targeting RACGAP1 suppresses growth hormone pituitary adenoma growth.

Growth hormone pituitary adenoma (GHPA) is a major subtype of pituitary adenoma (PA), with tumor enlargement and abnormal secretion of growth hormone (GH) often causing complications. Rac GTPase-activating protein 1 (RACGAP1), a member of the guanine triphosphatase-activating protein family, is highly overexpressed in multiple tumors and promotes tumor growth. However, the role of RACGAP1 in GHPA remains unelucidated. Besides, specific inhibitors targeting RACGAP1 have not yet been developed. In this study, we aimed to determine the expression and function of RACGAP1 in GHPA and identify effective inhibitors against RACGAP1. Immunohistochemistry was used to detect the expression of RACGAP1 in GHPA and normal pituitary tissues. The effect of RACGAP1 on cell proliferation, apoptosis, and cell cycle was evaluated by knockdown of RACGAP1 in GH3 cells in vitro and xenograft models of GHPA in vivo. The downstream mechanism of RACGAP1 was explored by RNA sequencing, bioinformatic analysis, and Western blot. Inhibitors targeting RACGAP1 were screened and verified through a structure-based virtual docking method, cell viability assays, and surface plasmon resonance (SPR) experiments. RACGAP1 expression was increased in GHPA compared with normal pituitary tissues. Knocking down RACGAP1 suppressed cell growth in vitro and in vivo. Preliminary mechanism studies indicated that inhibition of RACGAP1 led to the upregulation of p21 and the downregulation of several genes involved in the cell cycle signaling pathway, such as Cyclin A, CDK1, and CDK2. Moreover, DB07268 was identified for the first time as an effective RACGAP1 inhibitor that could prominently restrain the proliferation of GH3 cells. This study demonstrates that RACGAP1 plays a critical role in GHPA, highlighting the novel inhibitor DB07268 as a promising therapeutic approach.

PBLD enhances antiviral innate immunity by promoting the p53–USP4–MAVS signaling axis

Phenazine biosynthesis-like domain-containing protein (PBLD) has been reported to be involved in the development of many cancers. However, whether PBLD regulates innate immune responses and viral replication is unclear. In this study, although it was found that the activity of PBLD extends to other PRRs, we focused on the RLR pathway activated via the p53-USP4-MAVS axis in response to virus infections. We found that PBLD deubiquitinates and stabilizes MAVS through ubiquitin-specific protease 4 (USP4) to promote antiviral innate immunity. Mechanistically, PBLD activates the transcription of USP4 via the upregulation of p53. USP4, which is a MAVS-interacting protein, substantially stabilizes the MAVS protein by deconjugating K48-linked ubiquitination chains from the MAVS protein at Lys461 during RNA virus infection. Most intriguingly, RNA virus-infected primary macrophages (peritoneal macrophages, PMs, and bone marrow-derived macrophages, BMDMs) and internal organ cells (lung and liver) from PBLD-deficient mice suppress the IFN-I response and promote viral replication. Notably, PBLD-deficient mice are more susceptible to RNA virus infection than their wild-type littermates. Our findings highlight a unique function of PBLD in antiviral innate immunity through the p53-USP4-MAVS signaling, providing a preliminary basis for research on PBLD as a target molecule for treating RNA virus infection.

Network pharmacology‑based analysis and in vitro experimental verification of the inhibitory role of luteoloside on gastric cancer cells via the p53/p21 pathway.

The present study aimed to investigate the inhibitory effect of luteoloside on the proliferation, migration and invasion of gastric cancer (GC) cells based on network pharmacology and in vitro experiments. GC-associated targets were obtained from the GeneCards and Online Mendelian Inheritance in Man databases. Gene Ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed using the Database for Annotation, Visualization and Integrated Discovery. Protein-protein interaction (PPI) networks and herb-active ingredient-target gene-signaling pathway networks were constructed using the Search Tool for the Retrieval of Interacting Genes and proteins and Cytoscape software to analyze core target genes and pathways. In addition, the alkaline comet assay was performed to assess DNA damage, demonstrating that luteoloside induces DNA double-strand breaks in a concentration-dependent manner, as indicated by increased comet tail lengths. γ-H2AX detection through western blot analysis further corroborated these findings, showing significant upregulation of this DNA damage marker in luteoloside-treated GC cells. The human GC cell line NCI-N87 was utilized for in vitro experiments to investigate the impact of different doses of luteoloside on cell proliferation, invasion and migration using Cell Counting Kit-8, scratch-wound and Transwell assays, respectively. The underlying molecular mechanism of luteoloside was explored using western blot analysis. The successfully constructed PPI network revealed the p53, Akt1, Bcl-2 and Caspase-3 proteins as the core targets, all of which showed good binding activity with luteoloside. The in vitro experiments demonstrated that luteoloside treatment significantly inhibited GC-cell proliferation, migration and invasion. The western blot results showed notable concentration-dependent upregulation of p53 and p21 protein expression and downregulation of Bcl-2 protein expression following luteoloside treatment. Overall, luteoloside inhibited the proliferation, migration and invasion of GC cells by activating the p53/p21 signaling pathway.

Antitumor Activity of a Bispecific Chimera Targeting EGFR and Met in Gefitinib-Resistant Non-Small Cell Lung Cancer.

Non-small cell lung cancers (NSCLC) frequently acquire resistance to tyrosine kinase inhibitors (TKI) due to epidermal growth factor receptor (EGFR) mutation or activation of the bypass pathway involving mesenchymal-epithelial transition factor (Met). To address this challenge, a bispecific nanobody-aptamer chimera is designed to target mutated EGFR and Met simultaneously to block their cross-talk in NSCLC. The EGFR-Met chimera is cost-effectively engineered using microbial transglutaminase and click chemistry strategies. With enhanced binding affinity toward the target proteins, the as-developed chimera inhibits efficiently the cross-talk between signaling pathways associated with EGFR and Met. This inhibition leads to the suppression of downstream pathways, such as Erk and Akt, and induces upregulation of cell cycle arrest-related proteins, including Rb, p21, and p27. Additionally, the chimera activates the caspase-dependent apoptotic signaling pathway. Consequently, it inhibits cell migration, induces cell death, and causes cell cycle arrest in vitro. Moreover, the chimera exhibits significant antitumor efficacy in drug-resistant xenograft mouse models, showcasing improved tissue penetration and low toxicity. This study accentuates the potential of the bispecific EGFR-Met chimera as a promising therapeutic option for NSCLC resistant to EGFR TKIs.

Thymoquinone inhibits Neuroinflammatory mediators and vasoconstriction injury via NF-κB dependent NeuN/GFAP/Ki-67 in hypertensive Dams and F1 male pups on exposure to a mixture of Bisphenol-A analogues

Bisphenol-A (BPA) analogues seem inevitable components of numerous domestic products, but these have been identified as agents of teratogenic disorders. This study, therefore, investigated the effect of thymoquinone (TMQ) on the striatum of hypertensive female rats and their F1 male offsprings, on exposure to a mixture of Bisphenol-B, Bisphenol-F and Bisphenol-S (MBFS). Female rats were divided into normotensive and hypertensive groups; and both were treated with MBFS only, MBFS + TMQ, and TMQ only. Exposure to MBFS and co-treatment with TMQ lasted at least 63 days. Neurobehavioural assessments were conducted using Open Field (OF). A spectrophotometer was used for cholinergic, dopaminergic and adenosinergic enzyme assays; Real-Time PCR for gene expression; and immunohistochemistry for protein quantification; while H&E, cresyl fast violent, and congo red stains were used for histological assessments. From the results, maternal exposure to MBFS mediated striatal dysfunction via p53 and NF-kB upregulation; decreased BCl-2, Ki-67 and NeuN; increased GFAP, nissl bodies and β-amyloid. Dysregulation of cholinergic, dopaminergic and adenosinergic enzymes in addition to decreased nitric oxide levels were also associated with MBFS toxicity. Hypertension was found to exacerbate MBFS toxicity. From OF test; increased anxiety and decreased psychomotor activity were associated with maternal exposure to MBFS. However, co-treatment with thymoquinone prevented striatal dysfunction in hypertensive dams and their F1 male offspring. In conclusion, disruption of the delicate balance between apoptosis and cell proliferation culminating in the reduction of mature neurons is responsible for neurodegeneration and neuropathy associated with MBFS exposure. However, these can be prevented through regular consumption of natural products and supplements rich in thymoquinone.

Non-Immune-Mediated, p27-Associated, Growth Inhibition of Glioblastoma by Class-II-Transactivator (CIITA).

Previous works have shown that the expression of Class-II-Transactivator (CIITA) in tumor cells reduces the growth of glioblastoma (GB) in animal models, but immune effects cannot solely explain this. Here, we searched for immune-independent effects of CIITA on the proliferation of GB. Murine GL261 and human U87, GM2 and GM3 malignant glioma cells were transfected with CIITA. NSG (immunodeficient) and nude (athymic) mice were injected in the striatum with GL261-wildtype (-WT) and -CIITA, and tumor growth was assessed by immunohistology and luminescence reporter genes. Clonogenic, sphere-formation, and 3D Matrigel-based in vitro growth assays were performed to compare the growth of WT versus CIITA-expressing murine and human cells. Bulk RNA sequencing and RT2 qRT-PCR profiler arrays were performed on these four cell lines to assess RNA expression changes following CIITA transfection. Western blot analysis on several proliferation-associated proteins was performed. The intracerebral growth of murine GL261-CIITA cells was drastically reduced both in immunodeficient and athymic mice. Tumor growth was reduced in vitro in three of the four cell types. RNA sequencing and RT2 profiler array experiments revealed a modulation of gene expression in the PI3-Akt, MAPK- and cell-cycle regulation pathways following CIITA overexpression. Western blot analysis showed an upregulation of p27 in the growth-inhibited cells following this treatment. PDGFR-beta was downregulated in all cells. We did not find consistent regulation of other proteins involved in GB proliferation. Proliferation is drastically reduced by CIITA in GB, both in vivo and in vitro, notably in association with p27-mediated inhibition of cell-cycle pathways.

Contribution of p53-dependent and -independent mechanisms to upregulation of p21 in Fanconi anemia.

Abnormal expression of the cell cycle inhibitor and p53 target CDKN1A/p21 has been associated with paradoxical outcomes, such as hyperproliferation in p53-deficient cancer cells or hypoproliferation that affects hematopoietic stem cell behavior, leading to bone marrow failure (BMF). Notably, p21 is known to be overexpressed in Fanconi anemia (FA), which is a rare syndrome that predisposes patients to BMF and cancer. However, why p21 is overexpressed in FA and how it contributes to the FA phenotype(s) are still poorly understood. Here, we revealed that while the upregulation of p21 is largely dependent on p53, it also depends on the transcription factor microphthalmia (MITF) as well as on its interaction with the nucleolar protein NPM1. Upregulation of p21 expression in FA cells leads to p21 accumulation in the chromatin fraction, p21 immunoprecipitation with PCNA, S-phase lengthening and genetic instability. p21 depletion in FA cells rescues the S-phase abnormalities and reduces their genetic instability. In addition, we observed that reactive oxygen species (ROS) accumulation, another key feature of FA cells, is required to trigger an increase in PCNA/chromatin-associated p21 and to impact replication progression. Therefore, we propose a mechanism by which p21 and ROS cooperate to induce replication abnormalities that fuel genetic instability.

Repurposing flubendazole for glioblastoma ferroptosis by affecting xCT and TFRC proteins.

New uses of old drugs hold great promise for clinical translation. Flubendazole, an FDA-approved antiparasitic drug, has been shown to target p53 and promote apoptosis in glioblastoma (GBM) cells. However, its damaging mechanism in GBM remains elusive. Herein, we explored the ferroptosis-inducing ability of flubendazole on GBM cells. After treating glioma cell lines U251 and LN229 with the flubendazole (DMSO <1‰), cell viability was inhibited in a concentration-dependent manner (IC50 for LN229 = 0.5331 μM, IC50 for U251 = 0.6809 μM), attributed to the induction of ferroptosis, as evidenced by increased MDA levels, accumulation of ROS and lipid peroxides, change in mitochondrial membrane potential and structure. Protein analysis related to ferroptosis showed upregulation of TFRC, DMT1 and p53, alongside downregulation of xCT, FHC and GPX4 (p < 0.05). All-atom docking studies demonstrated that flubendazole bound closely with xCT, and TFRC, validating its role in inducing glioma ferroptosis via modulation of these proteins. Notably, flubendazole could damage the glioblastoma stem cells (GSC) that are typically resistant to other therapies, thereby possessing advantages in stopping glioma recurrence. This study delved into the mechanisms of flubendazole-induced ferroptosis in glioma, broadening its application and providing new ideas for new uses of other old drugs.

Stenochlaena palustris Ethanol Extract Decreases Viability and Induces G1-Phase Cell Cycle Arrest in HSC-3 Tongue Cancer Cells via p21 and p27

BACKGROUND: Oral squamous cell carcinoma (OSCC) of the tongue is an aggressive cancer with a poor prognosis due to its resistance to standard treatments. Stenochlaena palustris, a medicinal fern containing bioactive compounds, has shown potential anticancer properties. However, there is a lack of studies addressing the effects of S. palustris ethanol extract (SPEE) on tongue cancer. This study examined the effects of SPEE on the cell viability and cell cycle of human squamous cell carcinoma (HSC)-3 tongue cancer cells.METHODS: SPEE was prepared with the maceration method. HSC-3 cells were treated with SPEE at concentrations of 100, 500, and 1000 µg/mL for 24 and 48 hours. Cell viability was measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle analysis was performed using flow cytometer. Immunoblotting was used to measure amount of cell cycle regulators, protein 21 (p21) and protein 27 (p27).RESULTS: SPEE treatment led to a significant decrease in HSC-3 viable cells in a concentration- and time-dependent manner, with the most pronounced effect at higher concentration and prolonged treatment time. There was a slightly increase in the percentage of cells in the Sub-G1 phase in SPEE-treated group, meanwhile there was a significant increase in the percentage of cells in the G1-phase. Increased amount of p21 and p27 were observed in SPEE-treated group.CONCLUSION: SPEE significantly inhibited HSC-3 cell proliferation in a concentration- and time-dependent manner, primarily by inducing G1-phase cell cycle arrest through the upregulation of p21 and p27. Taken together, SPEE could be a potential anti-cancer agent for tongue cancer cell. KEYWORDS: Stenochlaena palustris, tongue cancer, cytotoxic, cell cycle arrest, HSC-3 cells, p21, p27

Human epicardial adipose tissue-derived factors promote atrial endothelial dysfunction: role of pro-inflammatory cytokines and AT1R/NADPH oxidases/SGLT2 pro-oxidant pathway

Abstract Introduction Epicardial adipose tissue (EAT) has been suggested to contribute to left atrium dysfunction via paracrine mechanisms to induce endothelial dysfunction, pro-arrhythmogenic and pro-remodeling responses thereby favoring atrial fibrillation (AF) onset. Recently, sodium-glucose co-transporter2 inhibitors (SGLT2i) have been shown to reduce AF incidence, EAT volume, differentiation and inflammation, however, the underlying mechanisms are unknown. Purpose This study investigates the impact of human EAT-derived mediators on atrial endothelial cell function and, if so, to characterize the role of SGLT2 using the inhibitor empagliflozin (EMPA). Methods Epicardial and subcutaneous adipose tissues (SAT) were collected from 70 cardiac patients at a university hospital. Conditioned medium (CM, 24 h) from fats were applied to porcine atrial endothelial cells (AECs, first passage) for 24 h. Histology of tissues was assessed by haematoxylin and eosin staining, protein expression by Western blot analysis or immunofluorescence staining, mRNA levels by RT-qPCR, formation of reactive oxygen species (ROS) and nitric oxide (NO) by fluorescent probes, and pro-inflammatory cytokine levels by ELISA. Results Compared to SAT, EATs were more vascularized with increased infiltration of M1-like macrophages, expression of proinflammatory cytokines (IL-1ß, IL-6, TNF-α), markers of ECs VCAM-1 and eNOS, fibrosis TGF-β, NADPH oxidases NOX-1 and SGLT1/2. These effects were associated with a pro-oxidant response that was inhibited by neutralizing Abs directed against IL-1ß or IL-6, and by inhibition of either NOS, NADPH oxidases, ACE, AT1R or SGLT2. Levels of SGLT2 and ROS in EATs were higher in AF compared to non-AF patients and progressively increasing with age. CM of EATs showed higher concentrations of IL-1ß, IL-6, TNF-α and MCP-1 than that of SAT. Exposure of AECs to CM of EATs increased the level of oxidative stress that was positively correlated to the level of pro-inflammatory cytokines, and reduced basal and bradykinin-induced NO formation that was prevented by EMPA. It also resulted in upregulation of p53 and SGLT2 expression, and nuclear translocation of NF-kB by CM of the top quartile inflamed EATs but not by the lowest quartile of EATs or SATs, prevented by EMPA. Conclusion The findings indicate that compared to SATs, the EATs showed higher in situ expression and release of pro-inflammatory cytokines that contributed to oxidative stress involving the AT1R/NADPH oxidases/SGLT2 pro-oxidant pathway. CMs of inflamed EATs induced AECs dysfunction, oxidative stress and activation of NF-kB involving pro-inflammatory cytokines and SGLT2. Thus, SGLT2i appear as an interesting strategy to decrease EAT inflammation and improve endothelial function contributing to prevent cardiac remodeling and fibrotic responses.

Cetirizine platinum(IV) complexes with antihistamine properties inhibit tumor metastasis by suppressing angiogenesis and boosting immunity

The histamine (HA) in tumors plays critical roles in promoting metastasis. Herein, a series of cetirizine (CTZ) platinum(IV) complexes with antihistamine properties were developed as antimetastatic agents. Dual CTZ platinum(IV) complex with cisplatin core was screened out as a candidate displaying potent antiproliferative activities. More importantly, it exerted promising antimetastatic properties both in vitro and in vivo. Investigation of the mechanism revealed that serious DNA damage was induced, which further led to the upregulation of histone H2AX (γ-H2AX) and P53. The mitochondria-mediated apoptosis was ignited through the B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X protein (Bax)/caspase3 pathway. Moreover, the HA-histamine receptor H1 (HRH1) axis was inhibited, then the key signaling phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) was suppressed. Subsequently, the angiogenesis in tumors was restrained by suppressing the inflammatory and hypoxic microenvironment. Then, the antitumor immunity was reinforced by increasing the CD3+ and CD8+ T cells and promoting the polarization of macrophages from M2- to M1-type, which was associated with the blockade of programmed cell death ligand-1 (PD-L1) expression in tumors.

Activating p53Y220C with a Mutant-Specific Small Molecule.

TP53 is the most commonly mutated gene in cancer, but it remains recalcitrant to clinically meaningful therapeutic reactivation. We present here the discovery and characterization of a small molecule chemical inducer of proximity that activates mutant p53. We named this compound TRanscriptional Activator of p53 (TRAP-1) due to its ability to engage mutant p53 and BRD4 in a ternary complex, which potently activates mutant p53 and triggers robust p53 target gene transcription. Treatment of p53Y220C expressing pancreatic cell lines with TRAP-1 results in rapid upregulation of p21 and other p53 target genes and inhibits the growth of p53Y220C-expressing cell lines. Negative control compounds that are unable to form a ternary complex do not have these effects, demonstrating the necessity of chemically induced proximity for the observed pharmacology. This approach to activating mutant p53 highlights how chemically induced proximity can be used to restore the functions of tumor suppressor proteins that have been inactivated by mutation in cancer.

Senescence landscape in the liver following sepsis and senolytics as potential therapeutics.

Senescence, caused by cell-cycle arrest, is a hallmark of aging. Senescence has also been described in embryogenesis, wound healing, and acute injuries. Sepsis is characterized by a dysregulated host response to infection, leading to organ dysfunction and mortality. Most of the pathophysiology of human sepsis is recapitulated in the mouse model of polymicrobial sepsis, developed by cecal ligation and puncture (CLP). In this report, we demonstrate a rapid onset of cellular senescence in the liver of mice subjected to CLP-induced sepsis, characterized by the upregulation of p21, p53, and other senescence markers, including SA-βgal. Using RNAscope, confocal microscopy, and flow cytometry, we further confirm the emergence of p21-expressing senescence phenotype in the liver 24 h after sepsis induction. Senescence was observed in several cell types in the liver, including hepatocytes, endothelial cells, and macrophages. We determined the landscape of senescence phenotype in murine sepsis by single-cell sequencing, which further ascertained that this cell fate is not confined to any particular cell type but displays a heterogeneous distribution. Furthermore, we observed a significant reduction in mortality following sepsis when mice were treated with senolytics, a combination of dasatinib and quercetin, before the CLP surgery. Our experiments unequivocally demonstrated a rapid development of cellular senescence with sepsis and, for the first time, described the senescence landscape in the sepsis liver and the possible role of senescent cells in the worsening outcome following sepsis.

HIV Protein Nef Induces Cardiomyopathy Through Induction of Bcl2 and p21.

HIV-associated cardiovascular diseases remain a leading cause of death in people living with HIV/AIDS (PLWHA). Although antiretroviral drugs suppress the viral load, they fail to remove the virus entirely. HIV-1 Nef protein is known to play a role in viral virulence and HIV latency. Expression of Nef protein can be detected in different organs, including cardiac tissue. Despite the established role of Nef protein in HIV-1 replication, its impact on organ function inside the human body is not clear. To understand the effect of Nef at the organ level, we created a new Nef-transgenic (Nef-TG) mouse that expresses Nef protein in the heart. Our study found that Nef expression caused inhibition of cardiac function and pathological changes in the heart with increased fibrosis, leading to heart failure and early mortality. Further, we found that cellular autophagy is significantly inhibited in the cardiac tissue of Nef-TG mice. Mechanistically, we found that Nef protein causes the accumulation of Bcl2 and Beclin-1 proteins in the tissue, which may affect the cellular autophagy system. Additionally, we found Nef expression causes upregulation of the cellular senescence marker p21 and senescence-associated β-galactosidase expression. Our findings suggest that the Nef-mediated inhibition of autophagy and induction of senescence markers may promote aging in PLWHA. Our mouse model could help us to understand the effect of Nef protein on organ function during latent HIV infection.

Up-Regulation of miR-625-5p Correlates with Suppressed Sox2, Increased Apoptosis, and Cell Cycle Arrest via The PI3K/AKT Signalling Pathway in Acute Myeloid Leukaemia

Background: Up-regulation of the microRNA-625 and abnormal expression of the Sox2 gene have been studied and seen in several tumors. Few reports have also shown the aberrant expression of miR-625 and Sox2 expression in various cancers. Several studies have also confirmed that phosphatidylinositol 3' -kinase /protein kinase B pathways regulate hematological malignancies, including Acute Myeloid Leukemia (AML). Thus, this study aimed to investigate the effects of mir-625 up-regulation on proliferation, apoptosis, and cell cycle by targeting the Sox2 gene via the downstream Akt signaling pathway and cell cycle regulators, such as p21, p27, and cyclin E in the KG-1 cell line. Materials and Methods: Cells obtained from the KG-1 cell line were cultured and transfected with plasmid DNA (miR-625) and scrambled as the control using the Lonza electroporation system. Flow cytometry was used to evaluate cell cycle, proliferation, and apoptosis. Relative gene expression was validated by qRT-PCR. All data were analyzed using graph pad prism 7.01 and REST 2009. Results: KG-1 cells transfected with the mir625-GFP construct showed decreased proliferation, increased apoptosis, and induced cell cycle arrest. Low levels of Sox2, p21, cyclin E, and up-regulation of p27 were confirmed and validated by qRT-PCR ( P &lt; 0.05 ). Conclusion: MiR-625 can be a promising approach to aid in the treatment of AML. However, further studies are required in this field

Aberrant expression of miR-143/miR-223/miR4478 and miR145 as prognostic factor for colorectal cancer patients

Colorectal cancer (CRC) is a type of malignancy that develops in the colon or rectal region. It develops due to abnormal growth and proliferation of cells in the lining of the colon, forming a tumor. This study included tissue samples (56 malignant and 56 matched normal samples). miRNAs were determined and retrieved from miRBase database and moderated by p53 gene. Expression levels of miRNA were varied. Only miR-223 revealed greater expression than normal matched tissue. mMiR-143, miR-4478, and miR-145 exhibited lower expression than matched normal tissue. Only miR-143 and miR-145 showed considerable variations in the expression among groups while miR-4478 did not demonstrate statistically substantial difference. In conclusion, this study highlights that upregulation of P53 and miR-223 and downregulation of miR-145 and miR-143 were associated with cancer advancement and unfavorable prognosis in Saudi CRC patients, indicating P53, miR-223, miR-145 and miR-143 to be novel and valuable signatures for predicting the outcomes for patients with CRC.

SHARPIN is a novel gene of colorectal cancer that promotes tumor growth potentially via inhibition of p53 expression.

Colorectal cancer (CRC) is widely prevalent and represents a significant contributor to global cancer‑related mortality. There remains a pressing demand for advancements in CRC treatment modalities. The E3 ubiquitin ligase is a critical enzyme involved in modulating protein expression levels via posttranslational ubiquitin‑mediated proteolysis, and it is reportedly involved in the progression of various cancers, making it a target of recent interest in anticancer therapy. In the present study, using comprehensive expression analysis involving spatial transcriptomic analysis with single‑cell RNA sequencing in clinical CRC datasets, the ubiquitin‑associated protein Shank‑associated RH domain interactor (SHARPIN) was identified, located on amplified chromosome 8q, which could promote CRC progression. SHARPIN was found to be upregulated in tumor cells, with elevated expression observed in tumor tissues. This heightened expression of SHARPIN was positively associated with lymphatic invasion and served as an independent predictor of a poor prognosis in patients with CRC. In vitro and in vivo analyses using SHARPIN‑overexpressing or ‑knockout CRC cells revealed that SHARPIN overexpression upregulated MDM2, resulting in the downregulation of p53, while SHARPIN silencing or knockout downregulated MDM2, leading to p53 upregulation, which affects cell cycle progression, tumor cell apoptosis and tumor growth in CRC. Furthermore, SHARPIN was found to be overexpressed in several cancer types, exerting significant effects on survival outcomes. In conclusion, SHARPIN represents a newly identified novel gene with the potential to promote tumor growth following apoptosis inhibition and cell cycle progression in part by inhibiting p53 expression via MDM2 upregulation; therefore, SHARPIN represents a potential therapeutic target for CRC.

DDX41 dissolves G-quadruplexes to maintain erythroid genome integrity and prevent cGAS-mediated cell death.

Deleterious germline DDX41 variants constitute the most common inherited predisposition disorder linked to myeloid neoplasms (MNs). The role of DDX41 in hematopoiesis and how its germline and somatic mutations contribute to MNs remain unclear. Here we show that DDX41 is essential for erythropoiesis but dispensable for the development of other hematopoietic lineages. Using stage-specific Cre models for erythropoiesis, we reveal that Ddx41 knockout in early erythropoiesis is embryonically lethal, while knockout in late-stage terminal erythropoiesis allows mice to survive with normal blood counts. DDX41 deficiency induces a significant upregulation of G-quadruplexes (G4), noncanonical DNA structures that tend to accumulate in the early stages of erythroid precursors. We show that DDX41 co-localizes with G4 on the erythroid genome. DDX41 directly binds to and dissolves G4, which is significantly compromised in MN-associated DDX41 mutants. Accumulation of G4 by DDX41 deficiency induces erythroid genome instability, defects in ribosomal biogenesis, and upregulation of p53. However, p53 deficiency does not rescue the embryonic death of Ddx41 hematopoietic-specific knockout mice. In parallel, genome instability also activates the cGas-Sting pathway, which is detrimental to survival since cGas-deficient and hematopoietic-specific Ddx41 knockout mice are viable without detectable hematologic phenotypes, although these mice continue to show erythroid ribosomal defects and upregulation of p53. These findings are further supported by data from a DDX41 mutated MN patient and human iPSC-derived bone marrow organoids. Our study establishes DDX41 as a G4 dissolver, essential for erythroid genome stability and suppressing the cGAS-STING pathway.