Activation Of Apoptotic Pathway Research Articles

Tannic Acid Impedes the Proliferation of Bladder Cancer Cells by Elevating Mitochondrial Pathways of Apoptosis.

Bladder cancer stands as a prevailing neoplasm among men globally, distinguished for its pronounced malignancy attributed to invasiveness and metastatic proclivity. Tannic acid (TA), an organic compound in many plants, has garnered recent attention for its discernible anti-mutagenic attributes. This investigation endeavored to scrutinize the repercussions of TA on grade II bladder cancer, with a concerted focus on unraveling its anti-cancer mechanisms. The cytotoxic effects of TA on grade II bladder cancer cells were investigated using multiple techniques, including MTT assay, flow cytometry, TUNEL assay, and western blot. Our findings revealed that elevated concentrations of TA induced cytotoxic effects in grade II bladder cancer cells. Both flow cytometry and the TUNEL assay substantiated the dose-dependent capacity of TA to prompt apoptosis. Western blot analysis corroborated that TA treatment in bladder cancer cells resulted in the upregulation of cleaved caspase-3 expression and PARP. Furthermore, heightened TA dosage elicited an augmentation in the expression of pro-apoptotic proteins, namely Bax and Bak, alongside a reduction in the expression of the anti-apoptotic protein Bcl-2 within bladder cancer cells. This study confirms TA as a potential anticancer agent, demonstrably diminishing the viability of bladder cancer cells. TA exerts cytotoxicity through the activation of mitochondrial apoptotic pathways. Specifically, TA initiates the cleavage of PARP and caspase-3, concurrently augmenting the expression of pro-apoptotic proteins to facilitate apoptosis. Collectively, the present study indicates that TA effectively impedes the proliferation of bladder cancer cells by instigating apoptosis through the intrinsic mitochondrial pathway.

The Antimicrobial PeptideTilapia Piscidin 4 Induced the Apoptosis of Bladder Cancer Through ERK/SIRT1/PGC-1α Signaling Pathway.

Marine antimicrobial peptides have been demonstrated in numerous studies to possess anti-cancer properties. This research investigation aimed to explore the fundamental molecular mechanisms underlying the antitumor activity of Tilapia piscidin 4 (TP4), an antimicrobial peptide, in human bladder cancer. TP4 exhibited a remarkable inhibitory effect on the proliferation of bladder cancer cells through cell cycle arrest at the G2/M phase. Additionally, TP4 upregulated the expression of cleaved caspase-3, caspase-9, and PARP, leading to the activation of apoptotic pathways in bladder cancer cells. TP4 exhibit a marked rise in mitochondria reactive oxygen species, leading to the subsequent loss of potential for the mitochondrial membrane. Furthermore, the inhibition of mitochondrial oxidative phosphorylation resulted in a decrease in downstream ATP production. Meanwhile, TP4-treated bladder cancer cells showed an increase in Bax and ERK but a decrease in SIRT1, PGC-1α, and Bcl2. ERK activation, SIRT1/PGC-1α-axis, and TP4-induced apoptosis were all significantly reversed by the ERK inhibitor SCH772984. Finally, the inhibitory effect of TP4 on tumor growth has been confirmed in a zebrafish bladder cancer xenotransplantation model. These findings suggest that TP4 may be a potential agents for human bladder cancer through apoptosis induction, ERK activation, and the promotion of SIRT1-mediated signaling pathways.

Anticancer activity of 8-hydroxyquinoline-triphenylphosphine rhodium(III) complexes targeting mitophagy pathways

Metallodrugs exhibiting distinct mechanisms of action compared with cisplatin hold promise for overcoming cisplatin resistance and improving the efficacy of anticancer drugs. In this study, a new series of rhodium (Rh)(III) complexes containing tris(triphenylphosphine)rhodium(I) chloride [(TPP)3RhCl] (TPP = triphenylphosphine, TPP=O = triphenylphosphine oxide) and 8-hydroxyquinoline derivatives (H-XR1–H-XR4), namely [Rh(XR1)2(TPP)Cl]·(TPP=O) (Yulin Normal University-1a [YNU-1a]), [Rh(XR2)2(TPP)Cl] (YNU-1b), [Rh(XR3)2(TPP)Cl] (YNU-1c), and [Rh(XR4)2(TPP)Cl] (YNU-1d), was synthesized and characterized via X-ray diffraction, mass spectrometry and IR. The cytotoxicity of the compounds YNU-1a–YNU-1d in Hep-G2 and HCC1806 human cancer cell lines and normal HL-7702 cell line was evaluated. YNU-1c exhibited cytotoxicity and selectivity in HCC1806 cells (IC50 = 0.13 ± 0.06 μM, selectivity factor (SF) = 384.6). The compounds YNU-1b and YNU-1c, which were selected for mechanistic studies, induced the activation of apoptotic pathways and mitophagy. In addition, these compounds released cytochrome c, cleaved caspase-3/pro-caspase-3 and downregulated the levels of mitochondrial respiratory chain complexes I/IV (M1 and M4) and ATP. The compound YNU-1c, which was selected for in vivo experiments, exhibited tumor growth inhibition (58.9 %). Importantly, hematoxylin and eosin staining and TUNEL revealed that HCC1806 tumor tissues exhibited significant apoptotic characteristics. YNU-1a–YNU-1d compounds are promising drug candidates that can be used to overcome cisplatin resistance.

Sensitivity and activation of endoplasmic reticulum stress response and apoptosis in the perinatal sheep heart.

We determined in vitro sensitivity to thapsigargin in sheep cardiomyocytes from four perinatal ages. In utero cardiac activation of endoplasmic reticulum (ER) stress and apoptotic pathways was determined at these same ages. Thapsigargin-induced phosphorylation of EIF2A decreased 72% between 135 and 143 dGA (P=0.0096) and remained low at 1 dPN (P=0.0080). Conversely, thapsigargin-induced caspase cleavage was highest around the time of birth: cleaved caspase 3 was highest at 1 dPN (3.8-fold vs. 135 dGA, P=0.0380; 7.8-fold vs. 5 dPN, P=0.0118), cleaved caspase 7 and cleaved caspase 12 both increased between 135 and 143 dGA (25-fold and 6.9-fold respectively, both P<0.0001), and remained elevated at 1 dPN. Induced apoptosis, measured by TUNEL assay, was highest around the time of birth (P<0.0001). There were changes in myocardial ER stress pathway components in utero. GRP78 protein levels were high in the fetus and declined after birth (P<0.0001). EIF2A phosphorylation was profoundly depressed at 1 dPN (vs. 143 dGA, P=0.0113). There is dynamic regulation of ER proteostasis, ER stress, and the apoptosis cascade in the perinatal heart. Apoptotic signaling is more readily activated in fetal cardiomyocytes near birth, leading to widespread caspase cleavage in the newborn heart. These pathways are important for regulation of normal maturation in the healthy perinatal heart.

Tivozanib-induced activation of the mitochondrial apoptotic pathway and suppression of epithelial-to-mesenchymal transition in oral squamous cell carcinoma.

The potential of tivozanib as a treatment for oral squamous cell carcinoma (OSCC) was explored in this study. We investigated the effects of tivozanib on OSCC using the Ca9-22 and CAL27 cell lines. OSCC is a highly prevalent cancer type with a significant risk of lymphatic metastasis and recurrence, which necessitates the development of innovative treatment approaches. Tivozanib, a vascular endothelial growth factor receptor inhibitor, has shown efficacy in inhibiting neovascularization in various cancer types but has not been thoroughly studied in OSCC. Our comprehensive assessment revealed that tivozanib effectively inhibited OSCC cells. This was accompanied by the suppression of Bcl-2, a reduction in matrix metalloproteinase levels, and the induction of intrinsic pathway-mediated apoptosis. Furthermore, tivozanib contributed to epithelial-to-mesenchymal transition (EMT) inhibition by increasing E-cadherin levels while decreasing N-cadherin levels. These findings highlight the substantial anticancer potential of tivozanib in OSCC and thus its promise as a therapeutic option. Beyond reducing cell viability and inducing apoptosis, the capacity of tivozanib to inhibit EMT and modulate key proteins presents the possibility of a paradigm shift in OSCC treatment.

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.

Exploring the link between pyrethroids exposure and dopaminergic degeneration through morphometric, immunofluorescence, and in-silico approaches: the therapeutic role of chitosan-encapsulated curcumin nanoparticles.

Introduction: The synthetic pyrethroid derivative fenpropathrin (FNE), a commonly used insecticide, has been associated with various toxic effects in mammals, particularly neurotoxicity. The study addressed the hallmarks of the pathophysiology of Parkinson's disease upon oral exposure to fenpropathrin (FNE), mainly the alteration of dopaminergic markers, oxidative stress, and molecular docking in rat models. In addition, the protective effect of curcumin-encapsulated chitosan nanoparticles (CRM-Chs-NPs) was also assessed. Methods: In a 60-day trial, 40 male Sprague Dawley rats were divided into 4 groups: Control, CRM-Chs-NPs (curcumin-encapsulated chitosan nanoparticles), FNE (15mg/kg bw), and FNE + CRM-Chs-NPs. Results: FNE exposure induced reactive oxygen species generation, ATP production disruption, activation of inflammatory and apoptotic pathways, mitochondrial function and dynamics impairment, neurotransmitter level perturbation, and mitophagy promotion in rat brains. Molecular docking analysis revealed that FNE interacts with key binding sites of dopamine synthesis and transport proteins. On the other hand, CRM-Chs-NPs mitigated FNE's toxic effects by enhancing mitochondrial dynamics, antioxidant activity, and ATP production and promoting anti-inflammatory and antiapoptotic responses. Conclusion: In summary, FNE appears to induce dopaminergic degeneration through various mechanisms, and CRM-Chs-NPs emerged as a potential therapeutic intervention for protecting the nervous tissue microenvironment.

Endoplasmic reticulum stress response favors cardiomyocyte apoptosis near birth

INTRODUCTION: One-third of cardiomyocyte are lost just before birth in the normally developing heart. The underlying reasons for this cell loss are unknown. We studied the role of the endoplasmic reticulum (ER) stress response in regulation of cardiomyocyte apoptosis in perinatal sheep hearts. We hypothesized that the signaling balance from survival to apoptosis changes just before the cardiomyocyte numbers decline, and that the ER stress response contributes. METHODS: Snap-frozen left ventricular (LV) samples and cultured cardiomyocytes from normally-growing lambs at 135 d of gestational age (dGA; term=147 dGA), 143 dGA and 1 d postnatal age (dPN) were used for this study (n=6 each age).Gene and protein regulation was studied by RT-PCR and western blot analysis. Parameters were compared by age by 1-way ANOVA followed, if justified, by Šídák's multiple comparisons test. RESULTS: In the LV, the ER stress master regulatory protein GRP78 was similar within fetal ages, but declined 32% between 143 dGA and 1 dPN (P= 0.0005), indicating less capacity for responding to misfolded proteins. eIF2α, downstream of GRP78, is critical for deciding the survival/apoptosis outcome following ER stress. Phosphorylation of eIF2α doubled between 135 dGA and 143 dGA (P=0.0015), implying increased ER stress in this period, and declined again at 1 dPN (p&lt;0.0001 vs. 143 dGA). Cleaved apoptosis effector caspase 3 protein peaked after birth; levels at 1 dPN were 1- to 2-fold higher than at other ages (p&lt;0.0001 vs. 135 dGA, P=0.002 vs. 143 dGA). Together, these data suggest that survival signaling in the ER stress pathway may be blunted between 135 and 143 dGA, as evidenced by diminished GRP78 expression and elevated eIF2α phosphorylation, resulting in activation of the apoptosis pathway. To better understand the mechanisms regulating dynamic perinatal changes in the ER stress response pathway, we studied sensitivity to ER stress (thapsigargin: 5 μM, 12 h) in cultured LV cardiomyocytes. In response to thapsigargin, GRP78 protein levels rose ~3-fold higher in cells from 135 dGA compared to 143 dGA or 1 dPN hearts (p&lt;0.0001), supporting diminishing survival signaling closer to the time of birth. Phosphorylation of eIF2α followed a similar pattern and was highest in 135 dGA cells (p&lt;0.0001 vs. 143 dGA and 1 dPN). This contrasts to the greater levels of phospho-eIF2α at 143 dGA in the tissue analysis. Thapsigargin stimulated 2-fold more cleavage of caspase 3 at 1 dPN than 135 dGA (P=0.0243), a similar timing as found in LV tissue. CONCLUSION: Findings suggest that at two weeks before birth, heart and cardiomyocytes are resilient to ER stress and stimulation of apoptosis, whereas nearer the time of birth there is a blunted ER stress response and increased activation of apoptotic pathways. R01HL142483 (Jonker), Collins Foundation (Bose). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

ANKZF1 knockdown inhibits glioblastoma progression by promoting intramitochondrial protein aggregation through mitoRQC

Protein homeostasis is fundamental to the development of tumors. Ribosome-associated quality-control (RQC) is able to add alanine and threonine to the stagnant polypeptide chain C-terminal (CAT-tail) when protein translation is hindered, while Ankyrin repeat and zinc-finger domain-containing-protein 1 (ANKZF1) can counteract the formation of the CAT-tail, preventing the aggregation of polypeptide chains. In particular, ANKZF1 plays an important role in maintaining mitochondrial protein homeostasis by mitochondrial RQC (mitoRQC) after translation stagnation of precursor proteins targeting mitochondria. However, the role of ANKZF1 in glioblastoma is unclear. Therefore, the current study was aimed to investigate the effects of ANKZF1 in glioblastoma cells and a nude mouse glioblastoma xenograft model. Here, we reported that knockdown of ANKZF1 in glioblastoma cells resulted in the accumulation of CAT-tail in mitochondria, leading to the activated mitochondrial unfolded protein response (UPRmt) and inhibits glioblastoma malignant progression. Excessive CAT-tail sequestered mitochondrial chaperones HSP60, mtHSP70 and proteases LONP1 as well as mitochondrial respiratory chain subunits ND1, Cytb, mtCO2 and ATP6, leading to mitochondrial oxidative phosphorylation dysfunction, membrane potential impairment, and mitochondrial apoptotic pathway activation. Our study highlights ANKZF1 as a valuable target for glioblastoma intervention and provides an innovative insight for the treatment of glioblastoma through the regulating of mitochondrial protein homeostasis.

SARS-CoV-2-ORF3a variant Q57H reduces its pro-apoptotic activity in host cells

Background Mutations in the viral genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can enhance its pathogenicity by affecting its transmissibility, disease severity, and overall mortality in human populations. In addition to mutations within the coding region of SARS-CoV-2 structural proteins, there have been reports of mutations in other SARS-CoV-2 proteins that affect virulence, such as open reading frame 3a (ORF3a), which is involved in viral replication. The expression of ORF3a in host cells activates cell death signaling, leading to tissue damage, which affects the severity of COVID-19. The ORF3a-Q57H variant is the most frequent and recurrent variant of ORF3a and is likely associated with increased transmissibility but lower mortality in the 4th epidemic wave of COVID-19 in Hong Kong. Computational structural modeling predicted that the Q57H variant destabilizes the protein structure of ORF3a, which may result in reduced protein expression in human cells. However, it is still unknown how this mutation affects ORF3a protein function and, if so, whether it can change the severity of host cell damage. Methods Plasmids carrying SARS-CoV-2-ORF3a from Wuhan-Hu-1 strain (i.e., wild-type; WT) and its variant Q57H were transiently transfected into HEK293T cells and used for biochemical and cell biological assays. Results SARS-CoV-2-ORF3a-Q57H variant exhibits higher protein expression than WT, but ORF3a-Q57H expression results in less apoptosis in host cells compared to WT via lower activation of the extrinsic apoptotic pathway. Conclusion The relatively mild phenotype of the SARS-CoV-2-ORF3a-Q57H variant may result from alterations to ORF3a function by this mutation, rather than its protein expression levels in host cells.

The relationship between aflatoxin B1 with the induction of extrinsic/intrinsic pathways of apoptosis and the protective role of taraxasterol in TM3 leydig cell line

Aflatoxins B1 (AFB1) a dangerous type of aflatoxin, poses a serious threat to human health. Meanwhile, Taraxasterol, a bioactive compound in dandelion, exhibits strong anti-inflammatory and antioxidant activity. Therefore, the aim of this study was to investigate the impact of AFB1 on the intrinsic and extrinsic pathways of apoptosis, as well as evaluate the protective role of taraxasterol in the TM3 Leydig cell line. Cell viability was evaluated using an MTT assay, measuring the effects of 3.6 µM AFB1 and varying concentrations of taraxasterol. Expression levels of Caspase 3,8, and 9 were analyzed with RT-qPCR, and flow cytometry was used to assess cell cycle progression and apoptotic alterations. The findings of this study demonstrated that exposure to 3.6 µM of AFB1 resulted in an upregulation of Caspase 3 and Caspase 9 expression, indicating an activation of apoptotic pathways in TM3 cells. Additionally, the analysis of apoptosis revealed a significant increase in cellular apoptosis at this AFB1 concentration. However, when TM3 cells were exposed to 5 µM of taraxasterol, a downregulation of Caspase 3 and Caspase 9 expression was observed, suggesting a protective effect against apoptosis. Moreover, the apoptotic rate in TM3 cells was reduced in the presence of 5 µM of taraxasterol. Consequently, this study highlights the potential of taraxasterol as a protective agent against AFB1-induced apoptosis and suggest its potential application in regulating cell survival and apoptosis-related processes. Further investigations are necessary to elucidate the underlying mechanisms and evaluate the clinical implications of taraxasterol in the context of fertility disorders and other conditions associated with AFB1 exposure.

P97 inhibits integrated stress response-induced neuronal apoptosis after subarachnoid hemorrhage in mice by enhancing proteasome function

Neuronal apoptosis is a common pathological change in early brain injury after subarachnoid hemorrhage (SAH), and it is closely associated with neurological deficits. According to previous research, p97 exhibits a remarkable anti-cardiomyocyte apoptosis effect. p97 is a critical molecule in the growth and development of the nervous system. However, it remains unknown whether p97 can exert an anti-neuronal apoptosis effect in SAH. In the present study, we examined the role of p97 in neuronal apoptosis induced after SAH and investigated the underlying mechanism. We established an in vivo SAH mice model and overexpressed the p97 protein through transfection of the mouse cerebral cortex. We analyzed the protective effect of p97 on neurons and evaluated short-term and long-term neurobehavior in mice after SAH. p97 was found to be significantly downregulated in the cerebral cortex of the affected side in mice after SAH. The site showing reduced p97 expression also exhibited a high level of neuronal apoptosis. Adeno-associated virus-mediated overexpression of p97 significantly reduced the extent of neuronal apoptosis, improved early and long-term neurological function, and repaired the neuronal damage in the long term. These neuroprotective effects were accompanied by enhanced proteasome function and inhibition of the integrated stress response (ISR) apoptotic pathway involving eIF2α/CHOP. The administration of the p97 inhibitor NMS-873 induced a contradictory effect. Subsequently, we observed that inhibiting the function of the proteasome with the proteasome inhibitor PS-341 blocked the anti-neuronal apoptosis effect of p97 and enhanced the activation of the ISR apoptotic pathway. However, the detrimental effects of NMS-873 and PS-341 in mice with SAH were mitigated by the administration of the ISR inhibitor ISRIB. These results suggest that p97 can promote neuronal survival and improve neurological function in mice after SAH. The anti-neuronal apoptosis effect of p97 is achieved by enhancing proteasome function and inhibiting the overactivation of the ISR apoptotic pathway.

The mechanisms of Porphyromonas gingivalis–derived outer membrane vesicles-induced neurotoxicity and microglia activation

Background/purposePeriodontitis is associated with various systemic diseases, potentially facilitated by the passage of Porphyromonas gingivalis outer membrane vesicles (Pg-OMVs). Several recent studies have suggested a connection between Pg-OMVs and neuroinflammation and neurodegeneration, but the precise causal relationship remains unclear. This study aimed to investigate the mechanisms underlying these associations using in vitro models. Materials and methodsIsolated Pg-OMVs were characterized by morphology, size, and gingipain activity. We exposed SH-SY5Y neuroblastoma cells and BV-2 microglial cells to various concentrations of Pg-OMVs. Cell morphology, a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, an enzyme-linked immunosorbent assay, and Western blot analysis were used to evaluate the cellular mechanism underlying Pg-OMV-induced neurotoxicity in neuronal cells and inflammatory responses in microglial cells. ResultsExposure to Pg-OMVs induced neurotoxicity in SH-SY5Y cells, as evidenced by cellular shrinkage, reduced viability, activation of apoptotic pathways, and diminished neuronal differentiation markers. Gingipain inhibition mitigated these effects, suggesting that gingipain mediates Pg-OMVs-induced neurotoxicity in SH-SY5Y cells. Our research on neuroinflammation suggests that upon endocytosis of Pg-OMVs by BV-2 cells, lipopolysaccharide (LPS) can modulate the production of inducible nitric oxide synthase and tumor necrosis factor-alpha by activating pathways that involve phosphorylated AKT and the phosphorylated JNK pathway. ConclusionOur study demonstrated that following the endocytosis of Pg-OMVs, gingipain can induce neurotoxicity in SH-SY5Y cells. Furthermore, the Pg-OMVs-associated LPS can trigger neuroinflammation via AKT and JNK signaling pathways in BV-2 cells.

Neferine Pretreatment Attenuates Isoproterenol-Induced Cardiac Injury Through Modulation of Oxidative Stress, Inflammation, and Apoptosis in Rats.

Heart attacks, also known as myocardial infarctions (MIs), are one of the main reasons people die from cardiovascular diseases (CVDs) worldwide. Neferine, an alkaloid derived from Nelumbo nucifera seeds, has garnered interest due to its purported medicinal effects. In the current research, we induced MI in rats using the β-adrenergic agonist isoproterenol to investigate whether neferine can improve cardiac dysfunction. The rats were separated into four groups: control, isoproterenol (ISO), and two treatment groups received neferine at doses of 10 or 20mg/kg once daily for 28days. On days 27 and 28, the groups undergoing treatment were administered with an ISO injection. Results showed that pretreatment with neferine strongly protected against changes in lipid profiles and cardiac functional markers in ISO-administered rats. Neferine attenuated histopathologic changes, collagen deposition, and myocardial fibrosis in rats administered ISO. Neferine pretreatment significantly inhibited the oxidative stress, inflammatory, and apoptotic markers in the heart of ISO-injected rats. This was achieved through Nrf2/Keap1/ARE signaling stimulation, TLR4/NF-κB/MAPK-mediated signaling inhibition, and activation of the intrinsic apoptotic pathway. Using CB-Dock-2, researchers determined that neferine has a high binding affinity with protein receptors that are pivotal in several biological processes. In conclusion, the study provides strong evidence that pretreatment with neferine protects rats from ISO-induced heart damage.

Abstract 351: Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing non-small cell lung carcinoma can induce cellular apoptosis

Abstract Anaplastic Lymphoma Kinase (ALK), a potent oncogenic driver in Non-Small Cell Lung Carcinoma (NSCLC), is found to be rearranged and fused to Echinoderm microtubule-associated protein-like 4 (EML4), contributing to approximately 5% of NSCLC as a distinct clinicopathological subset. Tumors bearing the EML4-ALK fusion are sensitive to ALK Tyrosine Kinase Inhibitors (TKIs), that form the first and second line of treatment for these patients. However, ALK+ lung cancers develop resistance to ALK inhibitors, creating the need for newer treatment strategies in ALK+ NSCLC. Tumor Suppressor Candidate 2 (TUSC2) is a tumor suppressor gene that is known to have low endogenous expression in NSCLC in general but data on TUSC2 in ALK+ lung cancers are not available. Quaratusugene ozeplasmid, developed by Genprex, is an immunogene therapy that upregulates TUSC2 expression in cancer cells by delivering the functional TUSC2 gene. It consists of the TUSC2 gene expressing plasmid encapsulated in non viral lipid nanoparticles. We evaluated TUSC2 expression in 3 ALK+ cell lines, both before and after exposure to quaratusugene ozeplasmid and to a TUSC2-containing plasmid. Controls were non-ALK+ cell lines and transfection with a plasmid containing no insert. Our studies in ALK+ lung cancer reveal that overexpressing TUSC2 using quaratusugene ozeplasmid treatment of ALK+ lung cancer cell lines is able to suppress colony formation by 50%, the effect being more significant than using a TUSC2-containing plasmid. Furthermore, we have observed a robust pro-apoptotic response to TUSC2 expression in ALK+ NSCLC, as both quaratusugene ozeplasmid and TUSC2-containing plasmid induced an increase in caspase 3/7 activity in the cancer cells, accompanied by an increase in cleaved PARP expression. Taken together, our data indicate that overexpression of TUSC2 in ALK+ NSCLC cell lines with quaratusugene ozeplasmid or with TUSC2-containing plasmid is effective in decreasing growth and proliferation through the activation of apoptotic pathways and warrants further investigation as an anti-ALK NSCLC strategy. Citation Format: Ananya Banerjee, Neeke Busette, Mark S. Berger, Matthew B. Soellner, Angel Qin, Sofia D. Merajver, Nathan M. Merrill. Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing non-small cell lung carcinoma can induce cellular apoptosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 351.

Protective benefits of ethyl alcohol extract of Piper betel L. to prevent colon carcinogenesis

Piper betel L. is a traditional nutritional and medicinal food, known for its rich phytochemical components. In the current study, the role of the ethyl alcohol extract of betel leaf (Piper betel) against human colorectal carcinoma (HT29 cells), was investigated. The extract consists of phenolic compounds and flavonoids that are potent antioxidants and antimicrobial agents. Exposure of human colon carcinoma cells, to the 80% ethyl alcohol extract resulted in apoptotic cell death, fragmentation, downregulation in the expression levels of Bcl-XL, and upregulation of p53. The results indicated the inhibition of cell proliferation in a dose-dependent manner. The results highlight the activation of the mitochondrial apoptotic pathway in response to the treatment with ethanolic extracts of betel leaves. The treatment induced DNA damage leading to G1 cell cycle arrest and apoptosis. Low cytotoxicity and anticarcinogenic effects of the ethyl alcohol extracts of betel leaf on HT29 suggest an alternative approach to human colon cancer therapy (combination therapy) and highlights its significance as a functional food or food supplement.

Abstract B012: Transcriptomic insights reveal role of BCL2 proteins in replication checkpoint inhibitor response

Abstract B012: Transcriptomic insights reveal role of BCL2 proteins in replication checkpoint inhibitor response

A germline point mutation in the MYC-FBW7 phosphodegron initiates hematopoietic malignancies.

Oncogenic activation of MYC in cancers predominantly involves increased transcription rather than coding region mutations. However, MYC-dependent lymphomas frequently acquire point mutations in the MYC phosphodegron, including at threonine 58 (T58), where phosphorylation permits binding via the FBW7 ubiquitin ligase triggering MYC degradation. To understand how T58 phosphorylation functions in normal cell physiology, we introduced an alanine mutation at T58 (T58A) into the endogenous c-Myc locus in the mouse germline. While MYC-T58A mice develop normally, lymphomas and myeloid leukemias emerge in ∼60% of adult homozygous T58A mice. We found that primitive hematopoietic progenitor cells from MYC-T58A mice exhibit aberrant self-renewal normally associated with hematopoietic stem cells (HSCs) and up-regulate a subset of MYC target genes important in maintaining stem/progenitor cell balance. In lymphocytes, genomic occupancy by MYC-T58A was increased at all promoters compared with WT MYC, while genes differentially expressed in a T58A-dependent manner were significantly more proximal to MYC-bound enhancers. MYC-T58A lymphocyte progenitors exhibited metabolic alterations and decreased activation of inflammatory and apoptotic pathways. Our data demonstrate that a single point mutation stabilizing MYC is sufficient to skew target gene expression, producing a profound gain of function in multipotential hematopoietic progenitors associated with self-renewal and initiation of lymphomas and leukemias.

Blocking acid-sensing ion channel1a attenuates bilirubin-induced ototoxicity in cochlear organotypic culture

Neonatal hyperbilirubinemia leads to neural dysfunction, including sensorineural hearing loss. Our previous studies demonstrated that elevated bilirubin induced apoptotic pathway activation and led to cell malformation in spiral ganglion neurons of neonatal rat cochlear organotypic explants. However, the underlying mechanisms remained unclear. Concurrent hyperbilirubinemia and acidemia would exacerbate neuronal damage. Acid-sensing ion channels (ASICs), which belong to the epithelial Na+ channel/degenerin (ENaC/DEG) superfamily, were activated during acidic pH fluctuations. To elucidate the roles of ASICs in bilirubin-induced ototoxicity, we treated postnatal cochlear explants of Sprague-Dawley rats with ASIC blockers and characterized the morphological and molecular alterations. Briefly, the basilar membrane and spiral ganglion neurons of the Sprague-Dawley rats at postnatal day 3 were cultured. The organotypic explants were randomly divided into control, bilirubin only, and bilirubin with ASIC blocker treatment groups. After 24 hours of culture, samples were taken for morphological molecular analysis. Our results showed that bilirubin-induced ototoxicity was alleviated in the alkalized environment and blocking ASIC1a protected cochleae from bilirubin-induced apoptosis. Transcriptomic analysis indicated that the profiles in ASIC1a blocker-treated group were similar to those in the control group, compared with the bilirubin-only treated cochleae group. The inhibition of ASIC1a suggests a potential attenuation of bilirubin-induced SGN degeneration, possibly through regulation of the MAPK signaling pathway. Taken together, our findings suggest that inhibiting ASIC1a alleviated bilirubin-induced ototoxicity in cochlear explants, with the protective effects being mediated, at least partially, via the MAPK signaling pathway. These findings shed light on the potential therapeutic targets for treating bilirubin-induced ototoxicity.

Alterations in histopathology and stress-associated gene expression induced by infection with Prohemistomum vivax encysted metacercariae in Nile tilapia

AbstractDue to limited data on the pathogenicity of Prohemistomum vivax (P. vivax) and its impacts on fish health, this study aimed to determine the morphological, molecular characteristics, pathogenicity, and histopathological alterations in fish infected with P. vivax. Eight hundred (800) Nile tilapia (Oreochromis niloticus) were collected from various farms in Kafr El Sheikh Governorate. The fish were examined for encysted metacercariae (EMC) in different organs. Tissue specimens were collected and underwent histopathological analysis, expression of stress-related genes, and genetic characterization by sequencing of the internal transcribed spacer 2 (ITS2). P. vivax metacercariae were oval to round in shape and were collected from various organs including the muscle, skin, eyes, intestine, liver, kidney, and gills of infected O. niloticus. Sequencing and phylogenetic analysis of the ITS2 region revealed a 507-bp fragment, confirming parasite identity and matching within the same clade as other P. vivax isolates. Infected fish displayed abdominal hydropsy, skin darkening, and emaciation. P. vivax encysted metacercariae were detected during the study period in 620/800 fish, with an overall prevalence of 77.5%. The seasonal prevalence was 95% in summer, 85% in spring, 55% in autumn, and 75% in winter. The intensity of infection was 1–40 cysts per microscopic field. Histopathological examination of muscles revealed parasitic cysts embedded within muscle fibers, causing severe degeneration and necrosis. Upregulation of cytochrome P450 (cpy1a1), heat shock protein 70 (hsp-70), and tumor suppressor p53 (p53) was recorded in both liver and muscle samples of infected tilapia compared to controls. This indicates activation of detoxification, cellular stress, and apoptotic pathways in response to P. vivax infection. There is limited data available on the pathogenicity of P. vivax and its impacts on fish health; thus, this study provides key insights into the morphology, pathogenicity, and histopathological impacts of P. vivax in Nile tilapia.