P21 Expression Research Articles

Ceftazidime is a potential drug to inhibit cell proliferation by increasing cellular p27.

The development of new therapeutic uses for existing drugs is important for the treatment of some diseases. Cephalosporin antibiotics stand as the most extensively utilized antibiotics in clinical practice, effectively combating bacterial infections. Here, we found that the antimicrobial drug ceftazidime strongly upregulates p27 protein levels by inhibiting p27 ubiquitination. The p27 protein is a classic negative regulator of thecell cycle. Next, we demonstrated that ceftazidime can impede the cell cycle from G1 to S phase, thus inhibiting cell proliferation. Furthermore, we found that ceftazidime promotes p27 expression and inhibits cell proliferation by reducing Skp2, which is a substrate recognition component of the Skp2-Cullin-F-box (SCF) ubiquitin ligase. Moreover, ceftazidime downregulates transcriptional expression of Skp2. Importantly, we demonstrated that ceftazidime inhibited the proliferation of tumor cells in vivo. These findings reveal ceftazidime-mediated inhibition of cell proliferation through the Skp2-p27 axis, and could provide a potential strategy for anti-tumor therapy.

EPEN-23. TARGETING TRISOMY MDM4 INDUCES CELL DEATH IN 1Q+ PFA EPENDYMOMA THROUGH REACTIVATION OF THE P53 PATHWAY

Abstract BACKGROUND Gain of chromosome 1q (1q+), gives a grave prognosis in pediatric posterior fossa group A ependymoma (PFA). The prevalence of 1q+ in newly diagnosed PFA stands at 25%, escalating to 50% upon recurrence. Conventional therapeutic modalities, such as complete resection and radiation, exhibit minimal efficacy in cases of 1q+ PFA, and the incorporation of additional chemotherapy in clinical trials has failed to yield substantial improvements. In this investigation, we delineate the trisomy-induced overexpression of the MDM4 gene on chromosome 1q as a driver of malignant progression in 1q+ PFA and a viable therapeutic target via idasanutlin, an MDM4 pathway inhibitor. METHODS We are using genetic and pharmaceutical inhibition of the MDM4/MDM2 pathway high-risk PFA 1q+ in vitro and in vivo models to test the efficacy of idasanutlin in a preclinical setting. Treatment effects are measured utilizing growth assays as well as genomic and transcriptomic analysis. RESULTS Our investigation reveals that two 1q+ in vitro models demonstrate a dose dependent sensitivity to idasanutlin compared to normal brain tissue. Upon exposure to idasnutlin, they also have an increase in p21 expression, a critical marker demonstrating reactivation of the p53 pathway, evidenced at both the gene expression and protein levels. Moreover, we found radiation synergistically enhances the efficacy of idasanutlin. Currently, we are evaluating our in vitro results with combination radiation and idasanutlin treatment in our 1q+ PFA preclinical in vivo models. CONCLUSIONS In summary, our study advocates for the exploration of small molecule inhibitors, with a primary focus on the promising idasanutlin compound, as a therapeutic avenue for addressing the challenge posed by ultra-high-risk 1q+ PFA. The compelling preclinical evidence presented herein lays the groundwork for advancing our understanding of the molecular intricacies underlying this malignancy, paving the way for novel and targeted treatment strategies.

Clinicopathological significance and prognostic analysis of p21 and EGFR in colorectal cancer: a retrospective analysis on 12 319 cases in China

AimsColorectal cancer (CRC) is the third most common malignancy worldwide. Accurate pathological diagnosis and predictive abilities for treatment response and prognosis are crucial for patients with CRC. This study aims...

Prx1/PHB2 axis mediates mitophagy in oral leukoplakia cellular senescence

BackgroundOral leukoplakia (OLK) is the most common oral potentially malignant disorder (OPMD), which can be malignantly transformed into oral squamous cell carcinoma (OSCC). Peroxiredoxin1(Prx1) has been predicted to bind to Prohibitin2 (PHB2), which confers to affect OLK progression; however, the mechanism of Prx1/PHB2 mediated mitophagy involved in OLK remains unclear. MethodsThis study aimed to explore the mechanism of the Prx1/PHB2 axis on senescence in OLK through mediating mitophagy. The positive rate of Ki67 and the expression of p21, p16, PHB2, and LC3 in human normal, OLK, and OSCC tissues were detected by immunohistochemical staining. The mitophagy and mitochondrial function changes were then analyzed in Prx1 knockdown and Prx1C52S mutations in dysplastic oral keratinocyte (DOK) cells treated with H2O2. In situ Proximity Ligation Assay combined with co-immunoprecipitation was used to detect the interaction between Prx1 and PHB2. ResultsClinically, the positive rate of Ki67 progressively increased from normal to OLK, OLK with dysplasia, and OSCC. Higher p21, p16, PHB2, and LC3 expression levels were observed in OLK with dysplasia than in normal and OSCC tissues. In vitro, PHB2 and LC3II expression gradually increased with the degree of DOK cell senescence. Prx1/PHB2 regulated mitophagy and affected senescence in H2O2-induced DOK cells. Furthermore, Prx1C52S mutation specifically reduced interaction between Prx1 and PHB2. Prx1Cys52 is associated with mitochondrial reactive oxygen species (ROS) accumulated and cell cycle arrest. ConclusionPrx1Cys52 functions as a redox sensor that binds to PHB2 and regulates mitophagy in the senescence of OLK, suggesting its potential as a clinical target.

Modulation of p53 and p21 Genes Expression in Cardiovascular Cultured Cells

This study explores the role of the p53 and p21 genes, central to the cell cycle arrest pathway, in cardiovascular diseases, focusing on their modulation by endocannabinoid ligands. Previous research has established the significance of CNR1 in cardiovascular regulation; however, its interaction with p53 pathways remains underexplored. We aimed to investigate the effects of Anandamide and Rimbonant on the expression levels of p53 and p21 in smooth muscle cells at both mRNA and protein levels. Our results indicate that Anandamide significantly increases p53 mRNA (3.191±0.38, Pv≤0.01) and protein (31.37±2.60) levels, while Rimbonant shows a decrease after 1 hour of treatment. Similarly, p21 expression was upregulated by Anandamide and downregulated by Rimbonant. These findings suggest that manipulating p53 activity through CNR1 ligands could potentially mitigate cardiovascular disease risks, warranting further investigation into their pharmacological applications. Highlights: Gene Modulation: Anandamide boosts p53 and p21 expression. Rimbonant Effects: Rimbonant reduces these gene levels. Therapeutic Potential: Indicates possibilities for cardiovascular disease treatment. Keywords: P53 Gene, Cardiovascular Disease, Endocannabinoids, Anandamide, Rimbonant

Chondroitin sulfate-functionalized selenium nanoparticle-induced S-phase cell cycle arrest and apoptosis in HeLa Cells.

This study aimed to evaluate the anti-cervical cancer activity of chondroitin sulfate-functionalized selenium nanoparticles (SeCS) and to elucidate their action mechanism. Cytotoxic effect of SeCS on HeLa cells was assessed by MTT assay. Further molecular mechanism of SeCS was analyzed by flow cytometric assay and western blotting. The results showed that treatment with SeCS resulted in a dose- and time-dependent inhibition in the proliferation of HeLa cells. The data obtained from flow cytometry demonstrated that SeCS inhibited HeLa cell growth via the induction of S-phase arrest and cell apoptosis. Further mechanism analysis found that SeCS down-regulated expression levels of cyclin A and CDK2 and up-regulated p21 expression, which contributed to S arrest. Moreover, SeCS increased the level of Bax and decreased the expression of Bcl-2, resulting in the release of cytochrome C from mitochondria and activating caspase-3/8/9 for caspase-dependent apoptosis. Meanwhile, intracellular reactive oxygen species (ROS) levels were elevated after SeCS treatment, suggesting that ROS might be upstream of SeCS-induced S-phase arrest and cell apoptosis. These data show that SeCS has anti-tumor effects and possesses the potential to become a new therapeutic agent or adjuvant therapy for cancer patients. PRACTICAL APPLICATION: In our previous study, we used chondroitin sulfate to stabilize nano-selenium to obtain SeCS to improve the bioactivity and stability of nano-selenium. We found that it possessed an inhibitory effect on HeLa cells. However, the molecular mechanism remains unclear. This study elucidated the mechanism of SeCS damage to HeLa cells. SeCS has the potential to become a new therapeutic agent or adjuvant therapy for cancer patients.

Loss of CFTR Reverses Senescence Hallmarks in SARS-CoV-2 Infected Bronchial Epithelial Cells.

SARS-CoV-2 infection has been recently shown to induce cellular senescence in vivo. A senescence-like phenotype has been reported in cystic fibrosis (CF) cellular models. Since the previously published data highlighted a low impact of SARS-CoV-2 on CFTR-defective cells, here we aimed to investigate the senescence hallmarks in SARS-CoV-2 infection in the context of a loss of CFTR expression/function. We infected WT and CFTR KO 16HBE14o-cells with SARS-CoV-2 and analyzed both the p21 and Ki67 expression using immunohistochemistry and viral and p21 gene expression using real-time PCR. Prior to SARS-CoV-2 infection, CFTR KO cells displayed a higher p21 and lower Ki67 expression than WT cells. We detected lipid accumulation in CFTR KO cells, identified as lipolysosomes and residual bodies at the subcellular/ultrastructure level. After SARS-CoV-2 infection, the situation reversed, with low p21 and high Ki67 expression, as well as reduced viral gene expression in CFTR KO cells. Thus, the activation of cellular senescence pathways in CFTR-defective cells was reversed by SARS-CoV-2 infection while they were activated in CFTR WT cells. These data uncover a different response of CF and non-CF bronchial epithelial cell models to SARS-CoV-2 infection and contribute to uncovering the molecular mechanisms behind the reduced clinical impact of COVID-19 in CF patients.

Anti-Leukemic Effects of Small Molecule Inhibitor of c-Myc (10058-F4) on Chronic Myeloid Leukemia Cells.

As one of the main molecules in BCR-ABL signaling, c-Myc acts as a pivotal key in disease progression and disruption of long-term remission in patients with CML. To clarify the effects of c-Myc inhibition in CML, we examined the anti-tumor property of a well-known small molecule inhibitor of c-Myc 10058-F4 on K562 cell line. This experimental study was conducted in K562 cell line for evaluation of cytotoxic activity of 10058-F4 using Trypan blue and MTT assays. Flow cytometry and Quantitative RT-PCR analysis were also conducted to determine its mechanism of action. Additionally, Annexin/PI staining was performed for apoptosis assessment. The results of Trypan blue and MTT assay demonstrated that inhibition of c-Myc, as shown by suppression of c-Myc expression and its associated genes PP2A, CIP2A, and hTERT, could decrease viability and metabolic activity of K562 cells, respectively. Moreover, a robust elevation in cell population in G1-phase coupled with up-regulation of p21 and p27 expression shows that 10058-F4 could hamper cell proliferation, at least partly, through induction of G1 arrest. Accordingly, we found that 10058-F4 induced apoptosis via increasing Bax and Bad; In contrast, no significant alterations were observed NF-KB pathway-targeted anti-apoptotic genes in the mRNA levels. Notably, disruption of the NF-κB pathway with bortezomib as a common proteasome inhibitor sensitized K562 cells to the cytotoxic effect of 10058-F4, substantiating the fact that the NF-κB axis functions probably attenuate the K562 cells sensitivity to c-Myc inhibition. It can be concluded from the results of this study that inhibition of c-Myc induces anti-neoplastic effects on CML-derived K562 cells as well as increases the efficacy of imatinib. For further insight into the safety and effectiveness of 10058-F4 in CML, in vivo studies will be required.

Qizhu anticancer prescription enhances immunosurveillance of liver cancer cells by regulating p21-dependent secretory phenotypes

Ethnopharmacological relevanceHepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, largely due to the limitations of available therapeutic strategies. The traditional Chinese medicine Qizhu Anticancer Prescription (QZACP) can improve the quality of life and prolong the survival time of patients with HCC. However, the precise mechanisms underlying the anti-cancer properties of QZACP remain unclear. PurposeThis study examined the anti-hepatocarcinogenic properties of QZACP, with a specific focus on its influence on the p21-activated secretory phenotype (PASP)-mediated immune surveillance, to elucidate the underlying molecular pathways involved in HCC. Materials and methodsCell proliferation was measured using the Cell Counting Kit-8, 5-ethynyl-2′-deoxyuridine, and clonogenic assays. The cell cycle was evaluated using flow cytometry, and senescence was identified by staining with senescence-associated beta-galactosidase (SA-β-gal). A primary liver cancer model produced by diethylnitrosamine was established in C57 BL/6 mice to assess the tumor-inhibitory effect of QZACP. The liver's pathological characteristics were examined using hematoxylin and eosin staining. PASP screening was performed using GeneCards, DisGeNet, Online Mendelian Inheritance in Man, and The Cancer Genome Atlas databases. Western blot analysis, enzyme-linked immunosorbent assay (ELISA), immunofluorescence staining, and Transwell migration assays were performed. ResultsSerum containing QZACP enhanced p21 expression, triggered cell cycle arrest, accelerated cell senescence, and suppressed cell proliferation in Huh7 and MHCC-97H liver cancer cells. QZACP reduced the quantity and dimensions of liver tumor nodules and enhanced p21 protein expression, SA-β-Gal staining in tumor lesions, and cytotoxic CD8+ T cell infiltration. Bioinformatic analyses indicated that PASP factors, including hepatocyte growth factor, decorin (DCN), dermatopontin, C-X-C motif chemokine ligand 14 (CXCL14), and Wnt family member 2 (WNT2), play an important role in the development of HCC. In addition, these factors are associated with the presence of natural killer cells and CD8+ T cells within tumors. Western blotting and ELISA confirmed that QZACP increased DCN, CXCL14, and WNT2 levels in tumor tissues and peripheral blood. ConclusionsQZACP's suppression of HCC progression may involve cell senescence mediated via p21 upregulation, DCN, CXCL14, and WNT2 secretion, and reversal of the immunosuppressive microenvironment. This study provides insights that can be used in the development of new treatment strategies for HCC.

Liraglutide prevents hyperglycemia-induced senescence and proinflammatory monocyte differentiation in CD34+ hematopoietic stem cells

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Italian Ministry of Health- Ricerca Finalizzata Background Diabetes mellitus (DM) is known to promote aberrant activation of immune cells that contribute to the onset and progression of chronic inflammation and atherosclerosis in DM patients (1). This phenomenon, termed 'trained immunity', appears to be initiated in hematopoietic stem/progenitor cells (HSPCs). In recent years, there has been great interest in investigating the pleiotropic effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs), including anti-inflammatory and immunological properties. We have recently demonstrated that HSPCs express the GLP-1R whose stimulation with the agonist liraglutide (LIRA) prevents oxidative stress and functional impairment induced by hyperglycemic conditions (HG) (2). On this basis, we hypothesized that LIRA treatment can also avert HG-induced senescence and proinflammatory myeloid differentiation of HSPCs. Purpose To evaluate senescence and inflammatory myeloid differentiation of CD34+ HSPCs after HG exposure in the presence or not of GLP1R agonist. Methods CD34+ HSPCs derived from cord blood of healthy donors were expanded in normal-glucose (NG; with 30 mM mannitol for osmotic control) or high-glucose (HG; 30 mM) and treated or not with LIRA (100nM) in serum-free medium plus cytokines (FLT3, SCF, IL3 and IL6) for up to 20 days. The expression of p21, p27, IL6, TNFα, and NFkB-p65 genes was assessed by qPCR. ROS production and CD34+ HSPC-derived monocyte subsets were evaluated by flow cytometry whereas cytokine secretion after LPS stimulation was measured by ELISA assay. Results LIRA treatment showed to significantly prevent the impairment of CD34+ HSPC proliferation as well as the upregulation of senescence-associated secretory phenotype (SASP) genes such as p21, p27, NFkB-p65, IL6, and TNFα in HG-CD34+ HSPCs when compared to HG cell alone (one-way ANOVA; p≤0.05). Interestingly, these pharmacological effects were associated with a significant reduction in HG-induced ROS production. Myeloid differentiation in vitro of HG-CD34+ HSPCs generated monocytes composed mainly of an inflammatory and highly reactive intermediate (CD14++CD16+) subpopulation characterized by higher LPS-induced release of IL6 and TNFα. LIRA treatment significantly prevented both the accumulation of intermediate (CD14++CD16+) monocyte subpopulation from differentiating HG-CD34+ HSPCs and their inflammatory phenotype (one-way ANOVA; p≤0.05). Conclusions These results demonstrate that HG exposure alters the differentiation program of CD34+ HSPCs towards more inflammatory immune cell components and suggest that GLP1R agonists are endowed with immunomodulatory properties that could be further developed and exploited for the treatment of immune system dysregulation in diabetes.

Therapeutic targeting of ARID1A-deficient cancer cells with RITA (Reactivating p53 and inducing tumor apoptosis)

ARID1A, a component of the SWI/SNF chromatin-remodeling complex, is frequently mutated in various cancer types and has emerged as a potential therapeutic target. In this study, we observed that ARID1A-deficient colorectal cancer (CRC) cells showed synthetic lethal effects with a p53 activator, RITA (reactivating p53 and inducing tumor apoptosis). RITA, an inhibitor of the p53-MDM2 interaction, exhibits increased sensitivity in ARID1A-deficient cells compared to ARID1A wild-type cells. Mechanistically, the observed synthetic lethality is dependent on both p53 activation and DNA damage accumulation, which are regulated by the interplay between ARID1A and RITA. ARID1A loss exhibits an opposing effect on p53 targets, leading to decreased p21 expression and increased levels of proapoptotic genes, PUMA and NOXA, which is further potentiated by RITA treatment, ultimately inducing cell apoptosis. Meanwhile, ARID1A loss aggravates RITA-induced DNA damage accumulation by downregulating Chk2 phosphorylation. Taken together, ARID1A loss significantly heightens sensitivity to RITA in CRC, revealing a novel synthetic lethal interaction between ARID1A and RITA. These findings present a promising therapeutic approach for colorectal cancer characterized by ARID1A loss-of-function mutations.

Inhibition of histone deacetylases class I improves adipogenic differentiation of human periodontal ligament cells.

Periodontal ligament stem cells (PDLSCs) show plasticity towards the adipogenic lineage; however, little has been done on the participation of epigenetic mechanisms. Histone acetylation is a dynamic process, though balanced by histone acetyltransferases (HATs) and histone deacetylases (HDACs) activities. This process can be halted by HDACs inhibitors, such as trichostatin A (TSA) and valproic acid (VPA). This study aimed to determine the role of HDACs class I in adipogenic differentiation of PDL cells. PDLSCs were treated with TSA at concentrations of 100, 200, and 250 nM, or VPA at 1, 4 and 8 mM. Cell viability was assessed using MTT assays. Gene expression of pluripotency markers (NANOG, OCT4, SOX2), HAT genes (p300, GCN5), and HDACs genes (HDAC1-3) was analyzed by RT-qPCR. Adipogenic differentiation was evaluated via oil red O staining, and acetylation of histone H3 lysine 9 (H3K9ac) was examined by Western blot. VPA treatment resulted in a 60% reduction in cell proliferation, compared to a 50% when using TSA. Cell viability was not affected by either inhibitor. Furthermore, both TSA and VPA induced adipogenic differentiation, through an increase in the deposition of lipid droplets and in GCN5 and p300 expression were observed. Western blot analysis showed that TSA increased H3K9ac levels on adipogenic differentiation of PDLSCs. These findings highlight the potential of HDAC inhibitors as a tool for modulating H3K9 acetylation status and thus influencing adipogenic differentiation of PDLCs.

Particulate matter exposure induces adverse effects on endometrium and fertility via aberrant inflammatory and apoptotic pathways in vitro and in vivo

This study aimed to evaluate the adverse effects of particulate matter (PM) exposure on endometrial cells and fertility and to identify possible underlying mechanisms. Thirteen women (aged 15–52 years) were included in this study. Enrolled patients underwent laparoscopic surgery at Gangnam Severance Hospital between 1 January and 31 December 2021. For in vivo experiments, 36 female and nine male C57BL/6 mice were randomly divided into control(vehicle), low-dose(10 mg/kg/d), and high-dose exposure groups(20 mg/kg/d). PM was inhaled nasally for four weeks and natural mating was performed. NIST® SRM® 1648a was used for PM exposure. qRT-PCR, western blotting and Masson's trichrome staining were performed. PM treatment in human endometrial stromal cells induced inflammation with significant upregulation of IL-1β, p–NF–kB, and p-c-Jun compared to those of controls. Additionally, PM treatment significantly increased apoptosis in human endometrial stromal cells by downregulating p-AKT and upregulating p-p53/p53, Cas-3, BAX/Bcl-2, p-AMPK, and p-ERK. After PM treatment, the relative expression of IL-1β, IL-6, TNF-α, p–NF–κB, p-c-Jun, and p-Nrf2/Nrf2 significantly increased in murine endometrium compared to those of the controls. Expression of apoptotic proteins p53, p27, and Cas-3, was also significantly elevated in murine endometrium of the PM exposure group compared to that of the controls. A significant increase in expression of procollagen Ⅰ, and Masson's trichrome staining scores in the murine endometrium was noted after PM treatment. PM treatment significantly decreased ERα expression. After natural mating, all 3 female mice in the control group gave birth to 25 offspring (mean 8.1), whereas in the low-dose PM treatment group, two of three female mice gave birth to nine offspring (mean 4.5). No pregnant mice or offspring was present in the high-dose PM treatment group. PM exposure induces adverse effects on the endometrium through aberrant activation of inflammatory and apoptotic pathways and is associated with detrimental effects on murine fertility.

#1219 Extracellular vesicles from patients with AMR-induced reprogramming of human podocytes into senescent cells: role of SGLT2i

Abstract Background and Aims Extracellular vesicles (EVs) are organelles released by different cells that deliver biological information into the extracellular space and contribute to several diseases. However, their role in patients with antibody-mediated allograft rejection (AMR) remains uncertain. Our aim was to test the influence of plasma-derived EVs on human conditional immortalized podocytes (PODO) by investigating the possible role of dapagliflozin (Dapa) as a pharmacological agent. Methods Twenty-eight Rtx patients were included in the study, 14 with AMR, and 14 control TX patients (RTX). (CTRL). Plasma-derived Evs were used to stimulate PODO for 24 h, followed by exposure to 100 nM Dapa for 24 h. Differential ultracentrifugation at 110,000 g was applied, followed by counting with Nanosight and characterization by high-resolution flow cytometry according to the MISEV2018 criteria. PKH26 dye was used for the EVs-PODO incorporation study using Z-stack microscopy image acquisition. Total RNA and protein were extracted for gene expression and protein analysis, and the cells were fixed for immunostaining evaluation. Results We first found that upon activation with EV, PODO incorporated Es and shared them between cells; moreover, AMR-EVs led to an increased expression of tetraspanin marker of cell activation CD9 (p = 0.028) compared with CTRL. Importantly, the incubation of PODO with RTX-EVs induced a senescence-associated secretory phenotype (TNF alpha p = 0.0006, MCP1 p = 0.014); with cytoskeletal dysregulation and increase in gene expression and proteins involved in the epithelial to mesenchymal transition such as VIM (p = 0.026), senescence P21 (p = 0.04), inflammation CD44 (p = 0.034) with downregulation of Klotho (p = 0.002). Interestingly, incubation with Dapagliflozin significantly counteract PODO activation with reduction in P21 expression (p = 0.039) and an increase in Klotho (p = 0.047) abrogating inflammaging. Conclusions Our findings demonstrate that plasma EVs of AMR induced cellular senescence in PODO, reprogramming cellular processes such as cytoskeleton shape and composition, secretion of inflammatory cytokines, and decrease of the nephroprotective protein Klotho. This pathogenic process can be efficiently counteracted by SGLT2i.

#1593 ARGDRR, a novel disintegrin, attenuates AKI to CKD-related renal fibrosis

Abstract Background and Aims Acute kidney injury (AKI) can lead to progress renal fibrosis, resulting in chronic kidney disease (CKD) and end stage renal disease (ESRD). Nevertheless, the underlying pathological mechanisms remain unclear. Platelet activation has been demonstrated as one of the important factors involved in the pathophysiology of AKI, and studies show the therapeutic potential for using platelet inhibitors or antagonists in ischemia-reperfusion (IR)-induced AKI models. However, drug-induced side effects, including thrombotic microangiopathies (TMA)-related kidney damage, thrombocytopenia and bleeding, hinder clinical application in AKI or CKD treatment. Our newly developed dual effect disintegrin, ARGDRR, is derived from snake venom exert a high affinity to αIIbβ3 and αvβ3 binding affinity without causing bleeding and other thrombosis-related side effects. Method We performed a unilateral ischemia-reperfusion injury (UIRI) model to investigate integrin αIIb(Itga2b) and β3(Itgb3) mRNA levels in the injured kidney for 15 days. For exploring the therapeutic efficiency of ARGDRR in AKI, we administered ARGDRR post-ischemic injury and measured platelet activation after 24 hours using quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) for Itgb3, Lcn2, and CD42b. For exploring the therapeutic efficiency of ARGDRR in CKD progression, we administrated ARGDRR daily for 15 days after IRI with nephrectomy, and examined the difference of renal dysfunction, renal fibrosis, and cell death compared to sham group. Results We found that platelet activation with progressively increased mRNA level of platelet glycoprotein IIb-GPIIIa (Itga2b and Itgb3) in the UIRI kidney over time. After 24 hr of ischemic AKI, ARGDRR administration reduced Lcn2 and Itgb3 mRNA level and CD42b positive area in the kidney, indicating its efficacy in protecting the kidneys by inhibiting platelet activation and aggregation. In AKI to CKD transition, serum creatine and blood urea nitrogen (BUN) were significantly lower both in efficacious and high dose of ARGDRR administration group. ARGDRR significantly reduced CD42b expression and increased LTL positive area. Also, ARGDRR administration alleviated renal fibrosis, cell apoptosis and senescence-related molecules p21 and Ctgf expression in the AKI to CKD transition. Conclusion Our results have successfully proved our hypothesis that disintegrin-ARGDRR has the potential for renal protection in the transition of AKI to CKD through inhibition of platelet activation and aggregation during acute injury.

Endoplasmic reticulum stress-induced senescence in human lung fibroblasts.

Loss of proteostasis and cellular senescence have been previously established as characteristics of aging; however, their interaction in the context of lung aging and potential contributions to aging-associated lung remodeling remains understudied. In this study, we aimed to characterize endoplasmic reticulum (ER) stress response, cellular senescence, and their interaction in relation to extracellular matrix (ECM) production in lung fibroblasts from young (25-45 yr) and old (>60 yr) humans. Fibroblasts from young and old patients without significant preexisting lung disease were exposed to vehicle, MG132, etoposide, or salubrinal. Afterward, cells and cell lysates or supernatants were analyzed for ER stress, cellular senescence, and ECM changes using protein analysis, proliferation assay, and senescence-associated beta-galactosidase (SA-β-Gal) staining. At baseline, fibroblasts from aging individuals showed increased levels of ER stress (ATF6 and PERK), senescence (p21 and McL-1), and ECM marker (COL1A1) compared to those from young individuals. Upon ER stress induction and etoposide exposure, fibroblasts showed an increase in senescence (SA-β-Gal, p21, and Cav-1), ER stress (PERK), and ECM markers (COL1A1 and LUM) compared to vehicle. Additionally, IL-6 and IL-8 levels were increased in the supernatants of MG132- and etoposide-treated fibroblasts, respectively. Finally, the ER stress inhibitor salubrinal decreased the expression of p21 compared to vehicle and MG132 treatments; however, salubrinal inhibited COL1A1 but not p21 expression in MG132-treated fibroblasts. Our study suggests that ER stress response plays an important role in establishment and maintenance of a senescence phenotype in lung fibroblasts and therefore contributes to altered remodeling in the aging lung.NEW & NOTEWORTHY The current study establishes functional links between endoplasmic reticulum (ER) stress and cellular senescence per se in the specific context of aging human lung fibroblasts. Recognizing that the process of aging per se is complex, modulated by the myriad of lifelong and environmental exposures, it is striking to note that chronic ER stress may play a crucial role in the establishment and maintenance of cellular senescence in lung fibroblasts.

Syndromic MEN1 Parathyroid Adenomas Consist of Both Subclonal Nodules and Clonally Independent Tumors

Abstract Background Primary hyperparathyroidism with parathyroid tumors is a characteristic presentation in Multiple Endocrine Neoplasia Type 1 (MEN1), historically referred to as "primary hyperplasia." The question of whether these tumors signify a multi-glandular clonal disorder or hyperplasia remains inconclusive. Loss of Menin protein expression serves as a reliable surrogate marker for biallelic inactivation and indicates a mutation in the MEN1 gene. The cyclin-dependent kinase inhibitor 1B (CDKN1B) gene, associated with MEN4, encodes the p27 protein, whose expression is inadequately explored in the context of syndromic MEN1. Aims The aim was to explore the molecular basis of syndromic MEN1 parathyroid adenomas, identifying hyperplasia, multiple independent clones, and the extent of Menin loss. Additionally, p27 expression was assessed to evaluate its potential in indicating a germline mutation, especially in distinguishing MEN4 as a clinical alternative to MEN1. Methods In this investigation, we examined histomorphology and protein expression of Menin and p27 in parathyroid adenomas from 25 patients in two independent, well-characterized MEN1 cohorts. Loss of heterozygosity (LOH) patterns were evaluated using fluorescence in situ hybridization (FISH) in one MEN1-associated parathyroid adenoma. Furthermore, next-generation sequencing (NGS) was conducted on eleven nodules from four MEN1 patients. Results Morphologically, the majority of MEN1 adenomas displayed multiple distinct nodules, characterized by predominantly lost Menin expression and reduced p27 protein expression. FISH analysis indicated that most nodules exhibited MEN1 loss, with or without centromere 11 loss. NGS demonstrated both subclonal evolution and the existence of clonally unrelated tumors. Conclusion Syndromic MEN1 parathyroid adenomas, therefore, consist of multiple clones with subclones, aligning with the current framework of the novel WHO classification of parathyroid tumors (2022). The observed loss of p27 expression in a significant fraction of MEN1 parathyroids emphasizes the need for caution when inferring MEN4 solely based on p27 expression.

Decitabine-based nanoparticles for enhanced immunotherapy of hepatocellular carcinoma via DNA hypermethylation reversal

DNA methyltransferase (DNMT) inhibitor represents the first clinical breakthrough via targeting aberrant cancer epigenomes. Demethylation drugs such as decitabine can restore tumor suppressor gene (TSG) expression and function to achieve anti-tumor effect. Despite DNMT inhibitors have shown significant efficacy for treating leukemia, their application in solid tumor such as HCC is limited due to short in vivo half-lives. In this study, the DNMT1 inhibitor decitabine was first loaded into the Polylactic-co-glycolic acid (PLGA) spherical nanoparticles (Dec@PLGA). The vesicle of PD-L1 antibody and macrophage membrane (aMM) was further coated onto the surface of Dec@PLGA to finally synthesize Dec@PLGA@aMM. Dec@PLGA@aMM was in uniformed spherical structure with hydrodynamic particle size of 95.7 ± 9.1 nm and surface zeta potential of −15.1 ± 3.3 mV. Dec@PLGA@aMM significantly increased the expression of both p14 and p16 in a concentration-dependent manner. Dec@PLGA@aMM could enhance the tumor suppression through restoration of TSGs, which were epigenetically silenced by DNA hypermethylation. The Dec@PLGA@aMM group showed significantly (P < 0.05) less tumor volume than PBS group, PLGA@MM group, aPD-L1 group, PLGA@aMM group, decitabine group, Dec + aPD-L1 group, and Dec@PLGA@MM group. The decitabine could enhance aPD-L1-mediated immunotherapy of HCC via epigenetic alteration. This novel targeted PLGA NPs are aimed to treat HCC by decreasing DNA methylation and blocking PD-L1, thus providing new ideas for effective treatments via epigenetic alteration for HCC patients clinically.

Tris(1,3-dichloro-2-propyl) phosphate-induced cytotoxicity and its associated mechanisms in human A549 cells.

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphorus flame retardant and has been detected in various environmental matrices including indoor dust. Inhalation of indoor dust is one of the most important pathways for human exposure to TDCIPP. However, its adverse effects on human lung cells and potential impacts on respiratory toxicity are largely unknown. In the current study, human non-small cell carcinoma (A549) cells were selected as a cell model, and the effects of TDCIPP on cell viability, cell cycle, cell apoptosis, and underlying molecular mechanisms were investigated. Our data indicated a concentration-dependent decrease in the cell viability of A549 cells after exposure to TDCIPP for 48h, with half lethal concentration (LC50) being 82.6µM. In addition, TDCIPP caused cell cycle arrest mainly in the G0/G1 phase by down-regulating the mRNA expression of cyclin D1, CDK4, and CDK6, while up-regulating the mRNA expression of p21 and p27. In addition, cell apoptosis was induced via altering the expression levels of Bcl-2, BAX, and BAK. Our study implies that TDCIPP may pose potential health risks to the human respiratory system and its toxicity should not be neglected.

A novel mechanism of major ginsenosides from Panax ginseng against multiple organ aging in middle-aged mice: Phosphatidylcholine-myo-inositol metabolism based on metabolomic analysis

Aging is a complex, degenerative process associated with various metabolic abnormalities. Ginsenosides (GS) is the main active components of Panax ginseng, which has anti-aging effects and improves metabolism. However, the anti-aging effect and the mechanism of GS in middle-aged mice has not been elucidated. In this study, GS after 3-month treatment significantly improved the grip strength, fatigue resistance, cognitive indices, and cardiac function of 15-month-old mice. Meanwhile, GS treatment reduced the fat content and obviously inhibited histone H2AX phosphorylation at Ser 139 (γ-H2AX), a marker of DNA damage in major organs, especially in the heart and liver. Further, the correlation analysis of serum metabolomics combined with aging phenotype suggested that myo-inositol (MI) upregulated by GS was positively correlated with left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS), the main indicators of cardiac function. More importantly, liver tissue metabolomic analysis showed that GS increased MI content by promoting the synthesis pathway from phosphatidylcholine (PC) to MI for the inhibition of liver aging. Finally, we proved that MI reduced the percentage of senescence-associated β-galactosidase staining, γ-H2AX immunofluorescence staining, p21 expression, and the production of reactive oxygen species in H2O2-induced cardiomyocytes. These results suggest that GS can enhance multiple organ functions, especially cardiac function for promoting the healthspan of aging mice, which is mediated by the conversion of PC to MI in the liver and the increase of MI level in the serum. Our study might provide new insights into the potential mechanisms of ginsenosides for prolonging the healthspan of natural aging mice.