Promote Cell Death Research Articles

6-Gingerol Induced Apoptosis and Cell Cycle Arrest in Glioma Cells via MnSOD and ERK Phosphorylation Modulation.

6-gingerol, a bioactive compound from ginger, has demonstrated promising anticancer properties across various cancer models by inducing apoptosis and inhibiting cell proliferation and invasion. In this study, we explore its mechanisms against glioblastoma multiforme (GBM), a notably aggressive and treatment-resistant brain tumor. We found that 6-gingerol crosses the blood-brain barrier more effectively than curcumin, enhancing its potential as a therapeutic agent for brain tumors. Our experiments show that 6-gingerol reduces cell proliferation and triggers apoptosis in GBM cell lines by disrupting cellular energy homeostasis. This process involves an increase in mitochondrial reactive oxygen species (mtROS) and a decrease in mitochondrial membrane potential, primarily due to the downregulation of manganese superoxide dismutase (MnSOD). Additionally, 6-gingerol reduces ERK phosphorylation by inhibiting EGFR and RAF, leading to G1 phase cell cycle arrest. These findings indicate that 6-gingerol promotes cell death in GBM cells by modulating MnSOD and ROS levels and arresting the cell cycle through the ERFR-RAF-1/MEK/ ERK signaling pathway, highlighting its potential as a therapeutic agent for GBM and setting the stage for future clinical research.

Doxorubicin synergizes bortezomib-induced multiple myeloma cell death by inhibiting aggresome formation and augmenting endoplasmic reticulum/Golgi stress and apoptosis

BackgroundBortezomib is a standard treatment for multiple myeloma (MM), working by the accumulation of toxic misfolded proteins in cancer cells. However, a significant clinical challenge arises from the development of resistance to bortezomib in MM treatment. Aggresome, a subcellular structure enclosed within Vimentin, forms in response to proteasome inhibitors and sequesters misfolded proteins that are transported by histone deacetylase 6 (HDAC6) and Dynein for degradation via autophagy, thereby reducing bortezomib’s cytotoxic effects. Therefore, in this study, we screened several anticancer agents to identify those that could synergize with bortezomib to enhance cell death and block aggresome formation in the MM cell line U266B1.MethodsTo enhance bortezomib’s efficacy, we screened a range of anticancer compounds for their potential to promote cell death and inhibit aggresome formation in U266B1 MM cells. We utilized the trypan blue exclusion assay and immunofluorescence for evaluation, and explored the underlying mechanisms through Western blot analysis.ResultsDoxorubicin enhanced bortezomib-induced cytotoxicity while inhibiting aggresome formation. Mechanistic studies revealed that doxorubicin downregulated key aggresome components, including Vimentin, HDAC6, and Dynein, leading to accumulation of misfolded proteins and augmentation of proapoptotic and necroptotic pathways by intensifying endoplasmic reticulum (ER) and Golgi stress responses. Notably, doxorubicin did not enhance cell death triggered by proteasome inhibitors that do not induce aggresome formation. Furthermore, the combination of bortezomib and doxorubicin failed to produce synergy in the killing of MM cell lines that lacked aggresome-forming ability.ConclusionsDoxorubicin enhances bortezomib-induced cell death in MM by inhibiting aggresome formation and amplifying ER/Golgi stress and apoptosis. This study highlights the potential therapeutic benefits of combining bortezomib with doxorubicin for MM treatment.Graphical

Unveiling the Antibacterial Efficacy of a Benzonitrile Small Molecule, IITR00210, in Shigella Infection.

The escalating prevalence of bacterial infections and the rapid emergence of multidrug-resistant Gram-negative bacterial pathogens highlight an urgent demand for effective antibacterial agents. In this study, we report our findings on IITR00210, a small molecule belonging to the nitrile class. The small molecule demonstrates broad-spectrum activity against bacterial pathogens, specifically against enteric pathogens, and exhibits antibiofilm activity. IITR00210 displays potent bactericidal activity against enteropathogens, resulting in a reduction of bacterial counts greater than 3 Log10 CFU in time-kill kinetic assays. Mechanistic investigations revealed that IITR00210 induces bacterial cell envelope stress, leading to the alteration of the overall proton motive force (PMF). The disruption of PMF causes intracellular ATP dissipation and ultimately promotes cell death. The cell envelope stress generated in the presence of IITR00210 leads to a translational aberration. Importantly, IITR00210 exhibits a safe profile in in vitro and in vivo settings. The small molecule further showed potent intracellular antibacterial activity in polymorphonuclear cells infected with enteric pathogens and antiadhesion activity in mammalian cell lines. IITR00210 proves to be a promising therapeutic candidate, displaying a lack of stable resistance development, and it exhibited efficacy in the treatment of bacterial infections in a shigellosis murine model.

Abstract A024: Assessing Mitondiral Priming in Leukemia Using BH3 Complex Specific Antibodies (PRIMABS): Prediciting Patient Response to Apoptosis Inducing Drugs

Abstract Diagnostic tools for cancer therapy that enable oncologists to inform patients about the likely benefits of their treatment versus toxicity will empower patients to make evidence-based decisions about the management of their disease, and in some cases, their last phase of life. Here we provide a novel approach that measures key drug response features of individual cancer cells with the potential for providing prognostic/predictive diagnostic utility for practicing precision medicine. Most cancer treatments work though activation of the cell suicide program of apoptosis. This process is tightly regulated by the BCL-2 family of proteins whose members either prevent or promote cell death. The relative levels of, and the specific interactions between the pro-survival and pro-apoptotic family members that dictates the fate of all cells and determines their propensity to undergo apoptosis. Cells that more readily die in response to various stimuli are referred to as “primed”. Hence, the degree of priming of a tumor sample can be predictive of responses to anti-cancer drugs and can be established using a technique called “BH3 profiling”. The relevance of this method has been demonstrated but it has had only limited application. To address this limitation a unique panel of antibody-based reagents that are mitochondrial PRIMing state detecting Antibodies (PRIMABS), have been developed by our lab, as a novel approach to implementing personalized medicine and developing predicative diagnostic tests. These antibodies enable the degree of tumor cell priming to be determined directly, unlike BH3 profiling which is an indirect measure. The key innovation lies in the approach taken to determine the presence (or absence) of the critical pro-survival : pro-apoptotic protein complexes , as these are the principal determinants of cell priming.. Such PRIMAB reagents have hitherto not been available. Here we provide data outlining the methodology development as well as evidence demonstrating feasibility of PRIMABTM Dx platform for predicting AML and CLL patient response in retrospective studies. Our platform provides a PD biomarker that will become a clinical predictor of cancer cell response to treatments tat are intended to induce apopstosis in tumor cells. The PRIMABTM -DX platform will enable heretofore hard to achieve clinical applicability of priming measurements. This will be significant due to the important prognostic implications of PRIMAB-DxTM readouts and will provide insights into drug resistance and sensitivity mechanisms and lead to new treatment options for cancer patients. Citation Format: Michael Cardone. Assessing Mitondiral Priming in Leukemia Using BH3 Complex Specific Antibodies (PRIMABS): Prediciting Patient Response to Apoptosis Inducing Drugs [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr A024.

Antibacterial Activity of Phloretin Against Vibrio parahaemolyticus and Its Application in Seafood.

Although phloretin is widely utilized in the food industry as an additive, its effects on foodborne pathogens remain insufficiently investigated. This study aimed to evaluate the antimicrobial properties of phloretin (PHL) against Vibrio parahaemolyticus (V. parahaemolyticus) and to elucidate the potential mechanisms of action. After PHL treatment, alterations in the cell morphology, cell microstructure, and intracellular contents of V. parahaemolyticus were assessed. Scanning electron microscopy revealed substantial damage to cell integrity, subsequent to PHL treatment. A notable reduction in intracellular components, including proteins, ATP, and DNA, was observed in samples treated with PHL. PHL was shown to inhibit the activities of ATPase, β-galactosidase, and respiratory chain dehydrogenase in V. parahaemolyticus. Furthermore, it was demonstrated to elevate the intracellular levels of reactive oxygen species and promote cell death. After being applied to sea bass, shrimp, and oysters, PHL effectively inactivated V. parahaemolyticus in these seafoods. These findings demonstrate that PHL has potential for application in seafood to control V. parahaemolyticus.

Synergistic effect of curcumin and Piperine loaded Niosomal nanoparticles on acute pulmonary toxicity induced by Paraquat in mice.

Paraquat (PQ), a widely used non-selective herbicide, induces severe lung toxicity by promoting cell death and tissue necrosis through the generation of reactive oxygen species (ROS) and free radicals. This study aimed to develop and evaluate novel niosomal nanoparticles (NPs) encapsulating curcumin and piperine to mitigate PQ-induced acute pulmonary toxicity in Balb/c mice. The NPs were prepared using non-ionic surfactants and cholesterol via the thin film hydration method. Characterization revealed high encapsulation efficiency (>85%), proper particle sizes (264-286nm), narrow polydispersity index (PDI) (0.19±0.04 to 0.23±0.02), and good stability over 90days. Thermal analysis confirmed successful encapsulation of curcumin and piperine within the niosomal NPs. In vivo studies showed that PQ exposure significantly elevated ROS, lipid peroxidation (LPO), and protein carbonylation (PC) levels, while reducing glutathione (GSH) levels and impairing mitochondrial function (P<0.001). However, co-treatment with curcumin- and piperine-loaded niosomal NPs effectively reversed these effects (P<0.001), improving mitochondrial function. The combined formulation of curcumin and piperine in niosomal NPs offers a promising therapeutic strategy for treating PQ-induced pulmonary toxicity, likely due to enhanced bioavailability and potent antioxidant activity.

PHGDH Induction by MAPK is Essential for Melanoma Formation and Creates an Actionable Metabolic Vulnerability.

Overexpression of PHGDH, the rate-limiting enzyme in the serine synthesis pathway, promotes melanomagenesis, melanoma cell proliferation, and survival of metastases in serine-low environments such as the brain. Here, we found that PHGDH is universally increased in melanoma cells and required for melanomagenesis. While PHGDH amplification explained PHGDH overexpression in a subset of melanomas, oncogenic BRAFV600E also promoted PHGDH transcription through mTORC1-mediated translation of ATF4. Importantly, depletion of PHGDH in genetic mouse melanoma models blocked tumor formation. In addition to BRAFV600E-mediated upregulation, PHGDH was further induced by exogenous serine restriction. Surprisingly, BRAFV600E inhibition diminished serine restriction-mediated PHGDH expression by preventing ATF4 induction. Consequently, melanoma cells could be specifically starved of serine by combining BRAFV600E inhibition with exogenous serine restriction, which promoted cell death in vitro and attenuated melanoma growth in vivo. In summary, this study identified that PHGDH is essential for melanomagenesis and regulated by BRAFV600E, revealing a targetable vulnerability in BRAFV600E-mutant melanoma.

Toxicity, Antibacterial, Antioxidant, Antidiabetic, and DNA Cleavage Effects of Dextran-Graft-Polyacrylamide/Zinc Oxide Nanosystems.

Synthesis of metal oxide nanoparticles-polymer nanocomposites is an emerging strategy in nanotechnology to improve targeted delivery and reduce the toxicity of nanoparticles. In this study, we report biological effects of previously described hybrid nanocomposites containing dextran-graft-polyacrylamide/zinc oxide nanoparticles (D-PAA/ZnO NPs) prepared from zinc sulfate (D-PAA/ZnONPs(SO42-)) and zinc acetate (D-PAA/ZnONPs(-OAc)) focusing primarily on their antimicrobial activity. D-PAA/ZnONPs(SO42-) and D-PAA/ZnONPs(-OAc) nanosystems were tested in a complex way to assess their antioxidant activity (DPPH assay), antidiabetic potential (α-amylase inhibition), DNA cleavage activity, antimicrobial, and antibiofilm activity. In addition, the toxicity of D-PAA/ZnONPs(SO42-) and D-PAA/ZnONPs(-OAc) nanosystems against primary murine splenocytes was tested using MTT assay. The studied nanosystems inhibited E.coli growth. For all the investigated strains, minimum inhibitory concentrations (MICs) of D-PAA/ZnONPs(SO42-) and D-PAA/ZnONPs(-OAc) were in the range of 8mg/L-128mg/L and 16mg/L-128mg/L, respectively. The nanocomposites demonstrated effective antibiofilm properties as 94.27% and 86.43%. The compounds showed good antioxidant, anti-α-amylase, and DNA cleavage activities. D-PAA/ZnONPs(SO42-) and D-PAA/ZnONPs(-OAc) nanosystems reduced cell viability and promoted cell death of primary murine spleen cells at concentrations higher than those that proved to be antibacterial indicating the presence of therapeutic window. D-PAA/ZnONPs(SO42-) and D-PAA/ZnONPs(-OAc) nanosystems show antioxidant, antidiabetic, DNA cleavage, antimicrobial, and antibiofilm activity against the background of good biocompatibility suggesting the presence of therapeutic potential, which should be further investigated in vivo.

Combinatorial PARP and HDAC inhibition synergistically promotes cell death and overcomes cisplatin treatment tolerance in cervical cancer cell lines

Combinatorial PARP and HDAC inhibition synergistically promotes cell death and overcomes cisplatin treatment tolerance in cervical cancer cell lines

Prolonged glutamine starvation reactivates mTOR to inhibit autophagy and initiate autophagic lysosome reformation to maintain cell viability.

Autophagy, a cellular recycling mechanism, utilizes lysosomes for cellular degradation. Prolonged autophagy reduces the pool of functional lysosomes in the cell. However, lysosomal homeostasis is maintained through the regeneration of functional lysosomes during the terminal stage of autophagy, i.e. Autophagic lysosome reformation (ALR). Through confocal microscopy during glutamine starvation, we unravel the regeneration of tubules from autolysosomes by undertaking significant membrane remodeling, which majorly depends on mTOR reactivation, RAB7 dissociation, phosphatidyl inositol 3 phosphate (PI3P) dependent dynamin 2 and clathrin recruitment. In glutamine-starved cells, we found mTOR is the central modulator in regulating ALR initiation, and its pharmacological inhibition with rapamycin leads to a decrease in lysosomal tubulation. Moreover, RAB7 and Clathrin are essential for tubule elongation and it showed that siRNA targeting RAB7 and Clathrin restricts tubule initiation under glutamine starvation. In this setting, we examined the physiological relevance of ALR during prolonged glutamine deprivation and found that genetic and pharmacological inhibition of critical proteins involved in ALR promotes cell death in oral cancer cells, establishing ALR is essential for maintaining cell survival during stress.

Dextran-Graft-Polyacrylamide/Zinc Oxide Nanoparticles Inhibit of Cancer Cells in vitro and in vivo.

Tumor drug resistance and systemic toxicity are major challenges of modern anticancer therapy. Nanotechnology makes it possible to create new materials with the required properties for anticancer therapy. In this research, Dextran-graft-Polyacrylamide/ZnO nanoparticles were used. The study was carried out using prostate (DU-145, LNCaP, PC-3), breast (MDA-MB-231, MCF-7, MCF-7 Dox) cancer cells and non-malignant (MAEC, BALB/3T3 clone A31) cells. Zinc was visualized with fluorescence in vitro and in vivo. ROS and apoptotic markers were identified by cytometry. Zinc accumulation and histopathological changes in the tumor, liver, kidney, and spleen were evaluated in a rat model. ZnO nanoparticles dissociation and release of Zn2+ into the cytosol occurs in 2-3hours for cancerous and non-cancerous cells. ROS upregulation was detected in all cells. For non-malignant cells, the difference between the initial ROS level was insignificant. The rate of carbohydrate metabolism in cancer cells was reduced by nanosystems. Zinc level in the tumor was upregulated by 25% and 39% after treatment with nanosystems and doxorubicin combined, respectively. The tumor Walker-256 carcinosarcoma volume was reduced twice following mono-treatment with the nanocomplex and 65-fold lower when the nanocomplex was combined with doxorubicin compared with controls. In the liver, kidney and spleen, the zinc level increased by 10-15% but no significant pathological alterations in the tissues were detected. D-PAA/ZnO NPs nanosystems were internalized by prostate, breast cancer cells and non-malignant cells via endocytosis after short time, but cytotoxicity against non-cancer cells were significantly lower in vitro and in vivo. D-PAA/ZnO NPs nanocomplex efficiently promoted cell death of tumor cells without showing cytotoxicity against non-malignant cells making it a promising anti-cancer agent.

Palmitoylation licenses RIPK1 kinase activity and cytotoxicity in the TNF pathway

Tumor necrosis factor (TNF)-induced receptor-interacting serine/threonine protein kinase 1 (RIPK1)-mediated cell death, including apoptosis and necroptosis, is increasingly recognized as a major driver of inflammatory diseases. Cell death checkpoints normally suppress RIPK1 kinase to safeguard the organism from its detrimental consequences. However, the mechanisms licensing RIPK1 kinase activity when a protective checkpoint is disabled remain unclear. Here, we identified S-palmitoylation as a licensing modification for RIPK1 kinase. TNF induces RIPK1 palmitoylation, mediated by DHHC5 and dependent on K63-linked ubiquitination of RIPK1, which enhances RIPK1 kinase activity by promoting the homo-interaction of its kinase domain and promotes cell death upon cell death checkpoint blockade. Furthermore, DHHC5 is amplified by fatty acid in the livers of mice with metabolic dysfunction-associated steatohepatitis, contributing to increased RIPK1 cytotoxicity observed in this condition. Our findings reveal that ubiquitination-dependent palmitoylation licenses RIPK1 kinase activity to induce downstream cell death signaling and suggest RIPK1 palmitoylation as a feasible target for inflammatory diseases.

Developmental cues are encoded by the combinatorial phosphorylation of Arabidopsis RETINOBLASTOMA-RELATED protein RBR1.

RETINOBLASTOMA-RELATED (RBR) proteins orchestrate cell division, differentiation, and survival in response to environmental and developmental cues through protein-protein interactions that are governed by multisite phosphorylation. Here we explore, using a large collection of transgenic RBR phosphovariants to complement protein function in Arabidopsis thaliana, whether differences in the number and position of RBR phosphorylation events cause a diversification of the protein's function. While the number of point mutations influence phenotypic strength, phosphosites contribute differentially to distinct phenotypes. RBR pocket domain mutations associate primarily with cell proliferation, while mutations in the C-region are linked to stem cell maintenance. Both phospho-mimetic and a phospho-defective variants promote cell death, suggesting that distinct mechanisms can lead to similar cell fates. We observed combinatorial effects between phosphorylated T406 and phosphosites in different protein domains, suggesting that specific, additive, and combinatorial phosphorylation events fine-tune RBR function. Suppression of dominant phospho-defective RBR phenotypes with a mutation that inhibits RBR interacting with LXCXE motifs, and an exhaustive protein-protein interaction assay, not only revealed the importance of DREAM complex members in phosphorylation-regulated RBR function but also pointed to phosphorylation-independent RBR roles in environmental responses. Thus, combinatorial phosphorylation defined and separated developmental, but not environmental, functions of RBR.

Loss of miR-200c-3p promotes resistance to radiation therapy via the DNA repair pathway in prostate cancer

Radiotherapy represents a major curative treatment for prostate cancer (PCa), but some patients will develop radioresistance (RR) and relapse. The underlying mechanisms remain poorly understood, and miRNAs might be key players in the acquisition and maintenance of RR. Through their encapsulation in small extracellular vesicles (EVs), they can also be relevant biomarkers of radiation response. Using next-generation sequencing, we found that miR-200c-3p was downregulated in PCa RR cells and in their small EVs due to a gain of methylation on its promoter during RR acquisition. We next showed that its exogenous overexpression restores the radiosensitivity of RR cells by delaying DNA repair through the targeting of HP1α. Interestingly, we also observed downregulation of miR-200c-3p expression by DNA methylation in radiation-resistant lung and breast cancer cell lines. In summary, our study demonstrates that the downregulation of miR-200c-3p expression in PCa cells and in their small EVs could help distinguish radioresistant from sensitive tumor cells. This miRNA targets HP1α to delay DNA repair and promote cell death.

BcIRF5 activates bcTBK1 phosphorylation to enhance PANoptosis during GCRV infection

TBK1 is an important IFN antiviral signalling factor, and in previous work black carp TBK1 (bcTBK1) and black carp IRF5 (bcIRF5) together promoted cell death in GCRV-infected cells. In this research, bcTBK1 and bcIRF5 were investigated both in vivo and in vitro to delineate their individual and combined functions. This study demonstrated that both bcTBK1 and bcIRF5 expressions were modulated in response to GCRV infection across the intestine, gill, kidney and spleen. In bcgill cells, overexpression of bcTBK1 and bcIRF5 initially suppressed the expression of cell death-related genes, including RIPK1, caspase1, caspase3 and bax, but this suppression was negated upon GCRV infection. In vivo, mRNA expression levels of RIPK1 and related genes varied by tissue following bcTBK1 or bcIRF5 overexpression and GCRV infection. Notably, intracellular co-overexpression of bcTBK1 and bcIRF5 led to significant upregulation of caspase3, caspase1, bax, and IL1β, along with enhanced caspase3 activity post-GCRV infection. This co-expression correlated with higher survival rates in black carp during GCRV infection and increased caspase3 mRNA in the spleen and gills. Hematoxylin-eosin (HE) staining indicated disorganized spleen tissue and edematous, hyperplastic gill changes in co-transfected groups after infection. TUNEL staining of tissue sections showed that DNA breakage was significantly stronger in the co-transfected group than in the other groups during GCRV infection. Further phosphorylation experiments showed that bcIRF5 promoted phosphorylation modification of bcTBK1. Thus, these data suggest that bcIRF5 activates bcTBK1 by enhancing its phosphorylation and promotes PANoptosis in GCRV-infected cells.

Activating the NFE2L1-ubiquitin-proteasome system by DDI2 protects from ferroptosis.

Ferroptosis is an iron-dependent, non-apoptotic form of cell death initiated by oxidative stress and lipid peroxidation. Recent evidence has linked ferroptosis to the action of the transcription factor Nuclear factor erythroid-2 derived,-like-1 (NFE2L1). NFE2L1 regulates proteasome abundance in an adaptive fashion, maintaining protein quality control to secure cellular homeostasis, but the regulation of NFE2L1 during ferroptosis and the role of the ubiquitin-proteasome system (UPS) herein are still unclear. In the present study, using an unbiased proteomic approach charting the specific ubiquitylation sites, we show that induction of ferroptosis leads to recalibration of the UPS. RSL3-induced ferroptosis inhibits proteasome activity and leads to global hyperubiquitylation, which is linked to NFE2L1 activation. As NFE2L1 resides in the endoplasmic reticulum tethered to the membrane, it undergoes complex posttranslational modification steps to become active and induce the expression of proteasome subunit genes. We show that proteolytic cleavage of NFE2L1 by the aspartyl protease DNA-damage inducible 1 homolog 2 (DDI2) is a critical step for the ferroptosis-induced feed-back loop of proteasome function. Cells lacking DDI2 cannot activate NFE2L1 in response to RSL3 and show global hyperubiquitylation. Genetic or chemical induction of ferroptosis in cells with a disrupted DDI2-NFE2L1 pathway diminishes proteasomal activity and promotes cell death. Also, treating cells with the clinical drug nelfinavir, which inhibits DDI2, sensitized cells to ferroptosis. In conclusion, our results provide new insight into the importance of the UPS in ferroptosis and highlight the role of the DDI2-NFE2L1 as a potential therapeutic target. Manipulating DDI2-NFE2L1 activity through chemical inhibition might help sensitizing cells to ferroptosis, thus enhancing existing cancer therapies.

The role of Imp and Syp RNA-binding proteins in precise neuronal elimination by apoptosis through the regulation of transcription factors.

Neuronal stem cells generate a limited and consistent number of neuronal progenies, each possessing distinct morphologies and functions, which are crucial for optimal brain function. Our study focused on a neuroblast (NB) lineage in Drosophila known as Lin A/15, which generates motoneurons (MNs) and glia. Intriguingly, Lin A/15 NB dedicates 40% of its time to producing immature MNs (iMNs) that are subsequently eliminated through apoptosis. Two RNA-binding proteins, Imp and Syp, play crucial roles in this process. Imp+ MNs survive, while Imp-, Syp+ MNs undergo apoptosis. Genetic experiments show that Imp promotes survival, whereas Syp promotes cell death in iMNs. Late-born MNs, which fail to express a functional code of transcription factors (mTFs) that control their morphological fate, are subject to elimination. Manipulating the expression of Imp and Syp in Lin A/15 NB and progeny leads to a shift of TF code in late-born MNs toward that of early-born MNs, and their survival. Additionally, introducing the TF code of early-born MNs into late-born MNs also promoted their survival. These findings demonstrate that the differential expression of Imp and Syp in iMNs links precise neuronal generation and distinct identities through the regulation of mTFs. Both Imp and Syp are conserved in vertebrates, suggesting that they play a fundamental role in precise neurogenesis across species.

REDOX SIGNALLING IN THE PANCREAS IN HEALTH AND DISEASE.

This review addresses oxidative stress and redox signaling in the pancreas under physiological conditions as well as in acute pancreatitis, chronic pancreatitis, pancreatic cancer, and diabetes. Physiological redox homeodynamics is maintained mainly by NRF2/KEAP1, NF-κB, protein tyrosine phosphatases, peroxisome proliferator-activated receptor-γ co-activator 1α (PGC1α), and normal autophagy. Depletion of reduced glutathione in the pancreas is a hallmark of acute pancreatitis and is initially accompanied by disulfide stress, which is characterized by protein cysteinylation without increased glutathione oxidation. A cross-talk between oxidative stress, MAPKs, and NF-κB amplifies the inflammatory cascade, acting PP2A and PGC1α as key redox regulatory nodes. In acute pancreatitis, nitration of cystathionine-β synthase causes blockade of the trans-sulfuration pathway leading to increased homocysteine levels, whereas p53 triggers necroptosis in the pancreas through downregulation of sulfiredoxin, PGC1α, and peroxiredoxin 3. Chronic pancreatitis exhibits oxidative distress mediated by NADPH oxidase 1 and/or CYP2E1, which promotes cell death, fibrosis, and inflammation. Oxidative stress cooperates with mutant KRAS to initiate and promote pancreatic adenocarcinoma. Mutant KRAS increases mitochondrial ROS, which trigger acinar-to-ductal metaplasia and progression to PanIN. ROS are maintained at sufficient level to promote cell proliferation, whilst avoiding cell death or senescence through formation of NADPH and GSH, and activation of NRF-2, HIF-1/2α, and CREB. Redox signalling also plays a fundamental role in differentiation, proliferation, and insulin secretion of β-cells. However, ROS overproduction promotes β-cell dysfunction and apoptosis in type 1 and type 2 diabetes.

Lanostane triterpenoids from Ganoderma calidophilum exhibit potent anti-tumor activity by inhibiting PTP1B

The species Ganoderma calidophilum represents a distinct variety within the genus Ganoderma and used by the indigenous Li ethnic group as a medicinal agent for the prevention and treatment of cancer. However, the precise biological activity and role of G. calidophilum in antitumor treatment remain largely unresolved. Several lanostane triterpenoids have been isolated from G. calidophilum. The enzyme activity analysis revealed that four lanostane triterpenoids exhibited PTP1B inhibition activity, with minimal inhibition towards SHP2, SHP1, PTPN5, PTPRA, STEP and TCPTP. Molecular docking analysis demonstrated that these compounds primarily bind to the substrate recognition and entry regions of PTP1B. Further analysis indicated that among them, ganoderic aldehyde A (GAA) is a selective and non-competitive PTP1B inhibitor. GAA inhibited the proliferation, colony formation and migration of C33A and MDA-MB-231 cells in a dose-dependent manner. GAA has the capacity to induce apoptosis in a cell-type-specific manner, both in a caspase-dependent and -independent manner. PTP1B siRNA significantly reduced the cytotoxic effect of GAA, while overexpression of PTP1B significantly increased cell growth after GAA treatment. These findings confirm that PTP1B is a functional target of GAA. Research into the mechanisms of action of GAA has revealed that it could inhibit the activation of AKT by inhibiting PTP1B, while simultaneously activating p38, which promotes cell death. It is possible to develop specific PTP1B inhibitors based on the lanosterol triterpene skeleton. G. calidophilum has the potential to be developed into functional foods or drugs with the aim of preventing and treating cancer.

Mechanistic Regulation of Epidermal Growth Factor and Hormonal Receptors by Kinase Inhibitors and Organofluorines in Breast Cancer Therapy.

Differential expression patterns of growth factor (EGFR, HER-2) and hormonal (ER, PR) receptors in breast cancer (BC) remain crucial for evaluating and tailoring therapeutic interventions. This study investigates differential expression profiles of hormonal and growth factor receptors in BC patients and across age groups, major subclasses, disease stages and tumor histology and survival rates, the efficacy of emerging clinical trial drugs (Dabrafenib and Palbociclib) and elucidating their molecular interaction mechanisms for efficient therapeutic strategies. Gene and protein expression analysis in the normal vs BC and across age groups and major subclasses reveals divergent patterns as EGFR and HER-2 levels are reduced in tumors versus normal tissue, while ER and PR levels are higher, particularly in luminal subtypes. However, there was no significant difference in survival rates among high and low/medium expression levels of EGFR and PR receptors. Conversely, patients with high HER-2 and ER expression exhibited poorer survival rates compared to low or medium expression levels. The in vitro findings indicate that Dabrafenib exhibits greater effectiveness than Palbociclib in suppressing various BC cells such as MCF-7 (Luminal), MDA-MB-231 (Triple-Negative), SKBR-3 (HER-2 + ) proliferation, promoting cell death, (IC50 of Dab < Pal) at 24 and 48 h, ROS production, and reduced ER and PR, elevated HER-2 with no change in EGFR expression. Molecular simulation studies revealed Dabrafenib's thermodynamically stable interactions (ΔG), tighter binding, and less structural deviation in the order EGFR > HER-2 > ER > PR as compared to Palbociclib (HER-2 > ER > PR = EGFR). These results indicate that Dabrafenib, compared to Palbociclib, more effectively regulates breast cancer cell proliferation through specific interactions with hormonal and growth factor receptors towards a repurposing approach.