Induction Of Apoptosis Pathway Research Articles

Macromolecules with predominant β-pleated sheet proteins in extracellular vesicles released from Raphanus sativus L. var. caudatus Alef microgreens induce DNA damage-mediated apoptosis in HCT116 colon cancer cells

Plant-derived bioactive macromolecules (i.e., proteins, lipids, and nucleic acids) were prepared as extracellular vesicles (EVs). Plant-derived EVs are gaining pharmaceutical research interest because of their bioactive components and delivery properties. The spherical nanosized EVs derived from Raphanus sativus L. var. caudatus Alef microgreens previously showed antiproliferative activity in HCT116 colon cancer cells from macromolecular compositions (predominantly proteins). To understand the mechanism of action, the biological activity studies, i.e., antiproliferation, cellular biochemical changes, DNA conformational changes, DNA damage, apoptotic nuclear morphological changes, apoptosis induction, and apoptotic pathways, were determined by neutral red uptake assay, synchrotron radiation-based Fourier transform infrared microspectroscopy, circular dichroism spectroscopy, comet assay, 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and caspase activity assay, respectively. EVs inhibited HCT116 cell growth in concentration- and time-dependent manners, with a half-maximal inhibitory concentration of 675.4 ± 33.8 μg/ml at 48 h and a selectivity index of 1.5 ± 0.076. HCT116 treated with EVs mainly changed the cellular biochemical compositions in the nucleic acids and carbohydrates region. The DNA damage caused no changes in DNA conformation. The apoptotic nuclear morphological changes were associated with the increased apoptotic cell population. The apoptotic cell death was induced by both extrinsic and intrinsic pathways. EVs have potential as antiproliferative bioparticles.

Dissecting caspase-2-mediated cell death: from intrinsic PIDDosome activation to chemical modulation.

Caspase-2, a highly conserved member of the caspase family, is considered an initiator caspase that triggers apoptosis in response to some cellular stresses. Previous studies suggest that an intracellular multi-protein complex PIDDosome, induced by genotoxic stress, serves as a platform for caspase-2 activation. However, due to caspase-2's inability to process effector caspases, the mechanism underlying caspase-2-mediated cell death upon PIDDosome activation remains unclear. Here we conducted an unbiased genome-wide genetic screen and identified that the Bcl2 family protein BID is required for PIDDosome-induced, caspase-2-mediated apoptosis. PIDDosome-activated caspase-2 directly and functionally processes BID to signal the mitochondrial pathway for apoptosis induction. Additionally, a designed chemical screen identified a compound, HUHS015, that specifically activates caspase-2-mediated apoptosis. HUHS015-stimulated apoptosis also requires BID but is independent of the PIDDosome. Through extensive structure-activity relationship efforts, we identified a derivative with a potency of ~ 60 nmol/L in activating caspase-2-mediated apoptosis. The HUHS015-series of compounds act as efficient agonists that directly target the interdomain linker in caspase-2, representing a new mode of initiator caspase activation. Human and mouse caspase-2 differ in two crucial residues in the linker, rendering a selectivity of the agonists for human caspase-2. The caspase-2 agonists are valuable tools to explore the physiological roles of caspase-2-mediated cell death and a base for developing small-molecule drugs for relevant diseases.

Modulation of Apoptosis by Bovine Gammaherpesvirus 4 Infection in Bovine Endometrial Cells and the Possible Role of LPS in This Process.

The prevalent pathogens associated with bovine uterine infections are bacteria that appear to increase the host's susceptibility to secondary infections with other bacteria or viruses, among which BoGHV4 is the most frequently found. In this work, the study of the pathways of apoptosis induction was carried out on an experimental model of primary culture of endometrial cells, in order to know the implication of BoGHV4 and the presence of bacterial LPS in the pathogenesis of the bovine reproductive tract. For this, different staining techniques and molecular analysis by RT-PCR were used. The results obtained allowed us to conclude that the level of cell death observed in the proposed primary culture is directly related to the time of viral infection and the presence of LPS in BoGHV4 infection. The apoptosis indices in cells infected with BoGHV4 and BoGHV4 + LPS revealed a maximum that correlated with the appearance of cytopathic effects and the maximum viral titers in the model studied. However, morphological, biochemical, and molecular changes were evident during both early and late stages of apoptosis. These findings provide information on the factors that may influence the pathogenesis of BoGHV4 and help to better understand the mechanisms involved in virus infection.

Abstract 4736: Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma

Abstract Oral squamous cell carcinoma (OSCC) is a prevalent form of cancer that develops in the oral cavity, globally recognized as the eighth most commonly diagnosed cancer. Despite the application of standard surgical techniques or concurrent chemoradiotherapy, the prognosis for OSCC patients remains unsatisfactory. Initially, cisplatin, the primary and most frequently used chemotherapy agent for treating OSCC, demonstrates effectiveness in therapy. Nonetheless, chemoresistance frequently arises, leading to treatment failure, and this is intricately associated with the activation of hypoxia-inducible factor 1α (HIF-1α) signaling. Recent research has brought to light heightened levels of HIF-1α-mediated vascular endothelial growth factor (VEGF) and BCL-2 in OSCC tumor sites, which play crucial roles in regulating angiogenesis and anti-apoptotic processes within cancer cells. Additionally, interventions aimed at targeting anti-apoptotic molecules or augmenting the expression of pro-apoptotic molecules may represent promising strategies to overcome chemoresistance in OSCC. Therefore, HIF-1α/VEGF/BCL-2 axis could be considered a potential target for the development of chemopreventive and chemotherapeutic strategies for OSCC. Lenvatinib is a targeted multi-kinase inhibitor that can inhibit tumor growth and angiogenesis by blocking the activation of vascular endothelial growth factor receptor (VEGFR) 1-3, fibroblast growth factor receptor (FGFR) 1-4, platelet-derived growth factor receptor (PDGFR) α, as well as the proto-oncogenes RET and KIT. However, whether lenvatinib may sensitizes OSCC to cisplatin remains unclear. In our study, we used the MTT assay to prove the cytotoxicity of OSCC cells (SAS and MOC1 cells) was induced by cisplatin and lenvatinib. We employed flow cytometry to verify that the combination of lenvatinib and cisplatin can indeed trigger both extrinsic and intrinsic apoptotic pathways in OSCC cells. Furthermore, our demonstration revealed that the induction of apoptosis pathways by the combination of lenvatinib and cisplatin is associated with mitochondrial-dependent apoptosis and death receptor-dependent apoptosis. Then, transwell invasion and migration assay results proved the inhibition effect of lenvatinib combined with cisplatin in SAS and MOC1 cells. Furthermore, we indicated that the combination of lenvatinib and cisplatin can effectively inhibit angiogenesis and anti-apoptotic mechanisms mediated by the HIF-1α/VEGF/BCL-2 axis in OSCC cells. In summary, our results demonstrate that the combined treatment with lenvatinib and cisplatin enhances the response of OSCC cells under hypoxic conditions. Additionally, it aims to mitigate the negative impact of hypoxia on cisplatin's therapeutic effectiveness and increase the sensitivity of OSCC cells to cisplatin. Citation Format: Ying-Tzu Chen, Yan-Ting Tsai, Fei-Ting Hsu, Hsi-Feng Tu. Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma [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 4736.

Effect of Herniarin on Cell Viability, Cell Cycle, and Erk Protein Levels in Different Stages of Bladder Cancer Cells.

This study examines the potential of herniarin from tarragon, as an agent with multifaceted effects on bladder cancer cells and investigates herniarin's impact on cell viability, migration, cell cycle regulation, apoptosis induction, and Erk signaling pathways in bladder cancer cell lines, including RT-112 (grade 1, non-invasive), HTB9 (grade 2, invasive), and HT1376 (grade 3, invasive), through comprehensive in vitro experiments. The compound causes cell cycle arrest at distinct phases in different cell lines: G1/S arrest in RT112 cells, G2/M arrest in HTB9 cells, and S phase arrest in HT1376 cells. Furthermore, herniarin induces caspase-mediated apoptosis in various cell lines and simultaneously modulates protein levels of apoptotic and anti-apoptotic proteins, indicating its potential as a therapeutic agent. Herniarin's influence also extends to Erk signaling, a crucial pathway that regulates cell growth and differentiation. In conclusion, this study reveals herniarin's potential as a versatile agent in the treatment of bladder cancer.

Dipsacus Asperoides-Derived Exosomes-Like Nanoparticles Inhibit the Progression of Osteosarcoma via Activating P38/JNK Signaling Pathway.

Osteosarcoma is a prevalent and highly malignant primary bone tumor. However, current clinical therapeutic drugs for osteosarcoma are not suitable for long-term use due to significant side effects. Therefore, there is an urgent need to develop new drugs with fewer side effects. Dipsacus asperoides C. Y. Cheng et T. M. Ai, a traditional Chinese medicine, is commonly used for its anti-inflammatory, anti-pain, bone fracture healing, and anti-tumor effects. In this study, we investigated the effects of exosome-like nanoparticles derived from Dipsacus asperoides (DAELNs) on osteosarcoma cells in vitro and in vivo. DAELNs were isolated and purified from Dipsacus asperoides and their physical and chemical properties were characterized using transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). The cellular uptake of DAELNs in osteosarcoma cells was analyzed by PKH26 staining. The proliferation, invasion, migration, and apoptosis of osteosarcoma cells were assessed using CCK8 assay, EdU assay, colony-formation assay, transwell assay, wound healing assay, and mitochondrial membrane potential measurement, respectively. The regulatory mechanism of DAELNs inhibiting the progression of osteosarcoma via activating P38/JNK signaling pathway was investigated using Western blotting and immunohistochemistry. Moreover, the therapeutic effects of DAELNs were evaluated using in vivo small animal imaging assay, HE staining, and immunohistochemistry. Our results showed that DAELNs inhibited the proliferation, invasion, migration, and fostered the apoptosis of osteosarcoma cells in vitro and suppressed the tumor growth of osteosarcoma cells in a xenograft nude mouse model. Furthermore, the bio-distribution of DiD-labeled DAELNs showed preferential targeting of osteosarcoma tumors and excellent biosafety in histological analysis of the liver and kidney. Mechanistically, DAELNs activated the P38/JNK signaling pathway-induced apoptosis. Taken together, DAELNs are novel, natural, and osteosarcoma-targeted agents that can serve as safe and effective therapeutic approaches for the treatment of osteosarcoma.

Investigation of polysaccharide from Radix Aconiti Lateralis Preparata (Fuzi) cardio protective effect on doxorubicin-induced chronic cardiotoxicity.

Doxorubicin (DOX) is a chemotherapy drug for treating malignant tumours. However, its cardiotoxicity has limited its clinical application. The Radix Aconiti Lateralis Preparata, also known as Fuzi, has been used for treating heart failure. Nevertheless, there is still a deficiency of claeity as to whether the Fuzi polysaccharide (FPS) may prevent the side effects of DOX. Mice were intraperitoneally administered DOX (15 mg/kg) to establish a mouse model of DOX-induced chronic cardiotoxicity (DICC). The mice were then administered different doses of FPS or enalapril intragastrically. In the DOX group, the activity of CK-MB and LDH and the content of NT-proBNP in serum of mice were increased. Myocardial infiltration of inflammatory cells and cytoplasmic vacuolation occurred. Levels of NLRP3, ASC, Caspase-1, IL-1β, IL-18, IL-6, and Bax increased, whereas levels of Bcl-2, STAT3, and p-STAT3 decreased. After administering FPS (100 mg/kg and 200 mg/kg), there were reductions in CK-MB activity and NT-proBNP levels. Cytoplasmic vacuolation, interstitial infiltration of blood, and infiltration of inflammatory cells were alleviated. The changes in protein expression mentioned above were reversed. FPS can protect heart function and structure in DICC mice by inhibiting NLRP3 inflammasome-mediated pyroptosis and IL-6/STAT3 pathway-induced apoptosis.

Prioritization of potential pharmacological targets for the development of anti-hepatocarcinoma drugs modulating the extrinsic apoptosis pathway: the reconstruction and analysis of associative gene networks help

Prioritization of potential pharmacological targets for the development of anti-hepatocarcinoma drugs modulating the extrinsic apoptosis pathway: the reconstruction and analysis of associative gene networks help

Propolis: Intrinsic Pathway-Induced Apoptosis, G1 Cell Cycle Arrest, Reduced Chemotherapeutic Resistance in Adenocarcinoma, and Healthy Cell Preservation

Propolis: Intrinsic Pathway-Induced Apoptosis, G1 Cell Cycle Arrest, Reduced Chemotherapeutic Resistance in Adenocarcinoma, and Healthy Cell Preservation

The GluN2B-Containing NMDA Receptor Alleviates Neuronal Apoptosis in Neonatal Hypoxic-Ischemic Encephalopathy by Activating PI3K-Akt-CREB Signaling Pathwa.

Neonatal hypoxic-ischemic encephalopathy (HIE) is a disease caused by insufficient blood supply in the brain in newborns during the perinatal period. Severe HIE leads to patient death, and patients with mild HIE are at increased risk of cognitive deficits and behavioral abnormalities. The NMDA receptor is an important excitatory receptor in the central nervous system, and in adult hypoxic-ischemic injury both subtypes of the NMDA receptor play important but distinct roles. The GluN2A-containing NMDA receptor (GluN2A-NMDAR) could activate neuronal protective signaling pathway, while the GluN2B-NMDAR subtype is coupled to the apoptosis-inducing signaling pathway and leads to neuronal death. However, the expression level of GluN2B is higher in newborns than in adults, while the expression of GluN2A is lower. Therefore, it is not clear whether the roles of different NMDA receptor subtypes in HIE are consistent with those in adults. We investigated this issue in this study and found that in HIE, GluN2B plays a protective role by mediating the protective pathway through binding with PSD95, which is quite different to that in adults. The results of this study provided new theoretical support for the clinical treatment of neonatal hypoxic ischemia.

The Oligosaccharyltransferase Complex: A Novel Vulnerability in Multiple Myeloma

Abstract Multiple myeloma (MM) is described as a clonal expansion of malignant plasma cells in the bone marrow characterized by several clinical symptoms: bone lesions, hypercalcemia, anemia, serum monoclonal gammopathy, immune suppression, and multiple organ failure. Despite the success of advanced treatments, disease relapse is common and incurable. Thus, there is an unmet clinical need to identify novel targets for relapsed/refractory MM treatment. The oligosaccharyltransferase (OST) complex catalyzes the transfer of N-glycan to a nascent translated protein which is a critical step in N-glycosylation, the most abundant post-translational modification of secretory and membrane-bound proteins. Aberrant expression of the OST complex or N-glycosylation is a diagnostic marker for solid tumors. However, the roles of the OST complex and N-glycosylation in MM development are virtually unknown. The mammal OST complex has two isoforms: OST-A and OST-B, with distinct catalytic subunits. Both isoforms share six subunits: OST4, RPN1, RPN2, DDOST, DAD1, and TMEM258. Analyzing the publicly available genomic data, we found that the shared subunits of the OST complex are abundantly expressed in MM cell lines and MM patient-derived cells. The expression levels of the OST subunits in relapsed MM patients are significantly higher than those in newly diagnosed MM patients. Intriguingly, patients expressing elevated levels of the OST complex are highly correlated with poor prognosis. These findings lead us to hypothesize that the OST complex might play a crucial role in MM. To address this hypothesis, we used the CRISPR/Cas9 system to knockout the OST's shared subunits and found that MM cells are dependent on the OST complex. Deletion of DDOST and DAD1 (two central structural subunits of the OST complex) impaired MM cell growth, arrested the cell cycle, and induced apoptosis. Using the subcutaneous xenograft model, we found that knockout of DDOST or DAD1 suppressed MM growth in vivo and extended the survival of tumor-bearing mice. Intriguingly, suppression of the OST complex's enzymatic activity by a specific inhibitor, NGI-1, recapitulated the phenotypes of the OST complex deletion. Of note, NGI-1 sensitizes the MM cells and bortezomib-resistant MM cells (both MM cell lines and primary patient cells) to bortezomib treatment. Mechanistically, we found that disruption of the OST complex in MM cells significantly suppressed transcriptomic signatures of MM pathology (NF-κB signaling, glycolysis, MYC targets, and cell cycle) and induced apoptosis pathway as well as inflammatory pathway (interferon alpha and gamma). Intriguingly, we found that all known genes responsible for the bortezomib-resistant phenotype were significantly downregulated upon the suppression of the OST complex. In conclusion, we identified the OST complex as a novel vulnerability in MM cells. Targeting the OST complex incorporation with Bortezomib might provide a novel and effective combined treatment for relapsed/refractory MM patients. We're currently investigating the underlying mechanisms of how the OST complex regulates MM pathology and developing patient-derived xenograft models to validate the therapeutic efficacy of combined treatment (NGI-1 and Bortezomib).

Lycorine suppresses the malignancy of breast carcinoma by modulating epithelial mesenchymal transition and β-catenin signaling

Lycorine, an isoquinoline alkaloid can exhibit significant anti-cancer effects. The present study was conducted to illustrate the underlying mechanisms of action of lycorine on breast carcinoma under in vitro and in vivo settings Tandem Mass Tag assay and Kyoto Encyclopedia of Genes and Genomes analysis revealed that 20 signaling pathways were closely related to tumorigenesis, especially Wnt signaling pathway and tight junctions. The results demonstrated that lycorine evidently inhibited the proliferation of MDA-MB-231 and MCF-7 cells with IC50 values of 1.84 ± 0.21 μM and 7.76 ± 1.16 μM, respectively. It also blocked cell cycle in G2/M phase, caused a decrease in mitochondrial membrane potential, and induced apoptosis pathways through regulating caspase-3, caspase-8, caspase-9, and PARP expression. Moreover, lycorine effectively repressed the β-catenin signaling and reversed epithelial-mesenchymal transition (EMT) process. Furthermore, 4T1/Luc homograft tumor model was used to further demonstrate that lycorine significantly inhibited the growth and metastasis of breast tumor. These findings highlight the significance of lycorine as potential anti-neoplastic agent to combat breast cancer.

The effect of Fas/FasL pathway blocking on apoptosis and stemness within breast cancer tumor microenvironment (preclinical study).

Evasion of the immune system is the tumor's key strategy for its maintenance and progression. Thus, targeting the tumor microenvironment (TME) is considered one of the most promising approaches for fighting cancer, where immune cells within the TME play a vital role in immune surveillance and cancer elimination.FasL is one of the most important death ligands expressed by tumor-infiltrating lymphocytes (TILs) and plays a vital role in eliminating Fas-expressing cancer cells via Fas/FasL pathway-induced apoptosis. However, tumor cells can express elevated levels of FasL inducing apoptosis to TILs. Fas/FasL expression is linked to the maintenance of cancer stem cells (CSCs) within the TME, contributing to tumor aggressiveness, metastasis, recurrence, and chemoresistance.This study is considered the first study designed to block the overexpressed FasL on the tumor cells within TME mimicking tissue culture system using rFas molecules and supplementing the Fas enriched tissue culture system with blocked Fas - peripheral blood mononuclear cells PBMCs (using anti-Fas mAb) to protect them from tumor counterattack and augment their ability to induce tumor cell apoptosis and stemness inhibition.A significantly increased level of apoptosis and decreased expression of CD 44 (CSCs marker) was observed within the east tumor tissue culture system enriched with Fas molecules and anti-Fas treated PBMCs and the one enriched with Fas molecules only compared to the breast tumor tissues cultured alone (p <0.001). Accordingly, we can consider the current study as a promising proposed immunotherapeutic strategy for breast cancer.

Design and synthesis of phosphonate functionalized naphthalenediimide: Application to induce mitochondria mediated apoptosis in the human skin melanoma cells (SKMEL2)

New phosphonate functionalized naphthalenediimides (NDI-1 and NDI-2) have been synthesized and evaluated as potential drug candidates to treat the skin malignancy. The aforementioned candidates have resulted in an induced apoptosis pathway of cytotoxicity, at concentrations lower than 4&nbsp;µM, in human skin melanoma cells, and elicited a stronger apoptotic response in cells. Regulation of the Bcl2, Caspases, Bak1, Bax protein in NDI-induced apoptosis in cells has been analyzed by real time PCR, and the cell viability and apoptosis determined by flow cytometry. The obtained results indicate that NDI-induced apoptosis by regulation of Bcl2 and Bak1 occurs in human skin melanoma cells (SKMEL-2).

Abstract 6154: Imipramine induces apoptosis and inhibits metastasis via suppression of EGFR signaling pathway in bladder cancer

Abstract Bladder cancer (BC) is one of the most common malignant diseases of the urinary system, with poor prognosis and high recurrence and metastasis rate. Recent literatures suggested that BC patients have proportionately worse depression and mental health, as well as being at increased risk of suicidal death when compared to the general population, while relatively sane BC patients have a 2.2 times higher mortality rate, which means that depression can make BC worse. Imipramine is a tricyclic antidepressant, was used to treat neuropathic pain, nocturnal enuresis, and depression. Recently, imipramine has been reported to owns anti-tumor efficacy in various type of cancer. However, the effects and underlying mechanisms of imipramine on BC is remaining unclear. First, we indicated that imipramine may induce cytotoxicity of BC by MTT assay. Flow cytometry also showed that imipramine may trigger the loss of mitochondrial membrane potential, the accumulation of oxidative stress (ROS), and the activation of cleaved-caspase-3, -8 and -9. Our western blotting assay and immunofluorescence translocation staining also verified that imipramine markedly inhibited BC progression by inhibiting both EGFR/AKT/NFΚB and EGFR/ERK/NΚB signaling pathways. Furthermore, transwell and wound healing assay indicated that imipramine effectively reduced the metastatic ability of BC. In addition, the anti-tumor effect of imipramine was also validated by MB49 bearing animal model. Most importantly biochemistry level and pathology was not affected by imipramine. In conclusion, imipramine may not only suppressed BC progression by inactivation of EGFR/AKT/NFΚB and EGFR/ERK/NFΚB signaling pathways and induction of apoptosis pathways. These results suggested that imipramine has the opportunity to be a new therapeutic strategy for BC patients. Citation Format: Tsai Lin Lo, Jai-Jen Tsai, Fei-Ting Hsu, Yuan Chang. Imipramine induces apoptosis and inhibits metastasis via suppression of EGFR signaling pathway in bladder cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6154.

Morphological alterations in C57BL/6 mouse intestinal organoids as a tool for predicting chemical-induced toxicity.

Intestinal organoid may serve as an alternative model for toxicity testing. However, the linkage between specific morphological alterations in organoids and chemical-induced toxicity has yet to be defined. Here, we generated C57BL/6 mouse intestinal organoids and conducted a morphology-based analysis on chemical-induced toxicity. Alterations in morphology were characterized by large spheroids, hyperplastic organoids, small spheroids, and protrusion-loss organoids, which responded in a concentration-dependent manner to the treatment of four metal(loid)s including cadmium (Cd), lead (Pb), hexavalent chromium (Cr-VI), and inorganic trivalent arsenic (iAs-III). Notably, alterations in organoid morphology characterized by abnormal morphology rate were correlated with specific intestinal toxic effects, including reduction in cell viability and differentiation, induction of apoptosis, dysfunction of mucus production, and damage to epithelial barrier upon repeated administration. The benchmark dose (BMDL10) values of morphological alterations (0.007-0.195μM) were lower than those of conventional bioassays (0.010-0.907μM). We also established that the morphologic features of organoids upon Cd, Pb, Cr-VI, or iAs-III treatment were metal specific, and mediated by Wnt, bone morphogenetic protein, apoptosis induction, and Notch signaling pathways, respectively. Collectively, these findings provide novel insights into the relevance of morphological alterations in organoids to specific toxic endpoints and identify specific morphological alterations as potential indicators of enterotoxicity.

The Effect of Metformin on Bad, Bak, and Bim Pro-apoptotic Factors: A Molecular Dynamic Simulation Study

Background:Recent investigations have demonstrated that metformin treatment can decrease tumor incidence and growth using cell cycle arrest and induction of apoptosis pathway. However, it is not clear how metformin affects the factors involved in the apoptotic process.Objective:The present study aimed to determine the effect of metformin on Bak, Bad, and Bim pro-apoptotic proteins using docking and dynamics simulation studies.Method:The 3D structure of molecules was retrieved from PubChem and RCSB servers. Simulation and docking studies were conducted by Gromacs and AutoDock software. Next, molecular dynamics analysis was performed using Gromacs software. Moreover, LigPlot+V.4.5.3 software was applied for the determination of the hydrogen and hydrophobic interactions at the binding sites.Result:Our findings demonstrated that metformin has the highest affinity for binding the Bak protein. This binding occurred using four amino acid residues within the binding site of Bak with the minimum binding energy (-5.70 kcal/mol). The molecular docking of metformin to these pro-apoptotic factors significantly decreased the total energy and increased the coil secondary structure of Bak protein.Conclusion:According to our findings, metformin can alter the molecular dynamics property of these proteins which results in increased activity of these pro-apoptotic proteins and induction of apoptosis.

The Immunoregulatory Effect of Aconite Treatment on H22 Tumor-Bearing Mice via Modulating Adaptive Immunity and Natural Killer-Related Immunity.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and, in its advanced stages, has a 5-year survival rate of only 3% to 5%. Despite novel mechanisms and treatments being uncovered over the past few years, effective strategies for HCC are currently limited. Previous studies have proven that aconite can suppress tumor growth and progression and prevent the recurrence and metastasis of multiple cancers, but the underlying molecular mechanisms are largely unknown. In this study, different doses of aconite were applied to mice bearing subcutaneous HCC tumors. It was found that aconite had a therapeutic effect on H22 tumor-bearing mice in a dose-dependent manner by reducing tumor volumes and prolonging survival times, which could be attributed to the immunoregulatory effect of aconite. Furthermore, results showed that high-dose administration of aconite could enhance adaptive immunity and natural killer (NK) cell-mediated immunity by regulating the secretion of interferon-γ, upregulating T cells and NK cells, and modulating the expression of the NK cytotoxicity biomarker CD107a and the inhibitory receptor TIGIT. This study revealed a novel mechanism through which aconite exerts antitumor effects, not merely through apoptosis induction pathways, providing more sound evidence that aconite has the potential to be developed into an effective anti-HCC agent.

NF-κB/RelA controlled A20 limits TRAIL-induced apoptosis in pancreatic cancer

The emergence of resistance to systemic therapies in pancreatic ductal adenocarcinoma (PDAC) is still a major obstacle in clinical practice. Both, constitutive and inducible NF-κB activity are known as key players in this context. To identify differentially expressed and TRAIL resistance mediating NF-κB target genes, TRAIL sensitive and resistant PDAC cell lines were analyzed by transcriptome assays. In this context, A20 was identified as an NF-κB/RelA inducible target gene. Translational PDAC tissue analysis confirmed the correlation of elevated A20 protein expression with activated RelA expression in PDAC patients. In in vitro experiments, an elevated A20 expression is accompanied by a specific resistance toward TRAIL-mediated apoptosis but not to chemotherapeutic-induced cell death. This TRAIL resistance was attributed to A20´s E3-ligase activity-mediating Zink finger domain. Furthermore, the ubiquitin-binding scaffold protein p62 was identified as indispensable for the TRAIL-mediated apoptosis-inducing pathway affected by A20. The results of this study identify A20 as a possible therapeutic target to affect resistance to TRAIL-induced apoptosis in PDAC cells.

Inhibition of TIGAR Increases Exogenous p53 and Cisplatin Combination Sensitivity in Lung Cancer Cells by Regulating Glycolytic Flux.

The metabolism and apoptosis of tumor cells are important factors that increase their sensitivity to chemotherapeutic drugs. p53 and cisplatin not only induce tumor cell apoptosis, but also regulate the tumor cell metabolism. The TP53-induced glycolysis and apoptosis regulator (TIGAR) can inhibit glycolysis and promote more glucose metabolism in the pentose phosphate pathway. We speculate that the regulation of the TIGAR by the combination therapy of p53 and cisplatin plays an important role in increasing the sensitivity of tumor cells to cisplatin. In this study, we found that the combined treatment of p53 and cisplatin was able to inhibit the mitochondrial function, promote mitochondrial pathway-induced apoptosis, and increase the sensitivity. Furthermore, the expression of the TIGAR was inhibited after a combined p53 and cisplatin treatment, the features of the TIGAR that regulate the pentose phosphate pathway were inhibited, the glucose flux shifted towards glycolysis, and the localization of the complex of the TIGAR and Hexokinase 2 (HK2) on the mitochondria was also reduced. Therefore, the combined treatment of p53 and cisplatin may modulate a glycolytic flux through the TIGAR, altering the cellular metabolic patterns while increasing apoptosis. Taken together, our findings reveal that the TIGAR may serve as a potential therapeutic target to increase the sensitivity of lung cancer A549 cells to cisplatin.