Cell Signaling Pathways Research Articles

Radixin: Roles in the Nervous System and Beyond.

Radixin is an ERM family protein that includes radixin, moesin, and ezrin. The importance of ERM family proteins has been attracting more attention, and studies on the roles of ERM in biological function and the pathogenesis of some diseases are accumulating. In particular, we have found that radixin is the most dramatically changed ERM protein in elevated glucose-treated Schwann cells. We systemically review the literature on ERM, radixin in focus, and update the roles of radixin in regulating cell morphology, interaction, and cell signaling pathways. The potential of radixin as a therapeutic target in neurodegenerative diseases and cancer was also discussed. Radixin research has focused on its cell functions, activation, and pathogenic roles in some diseases. Radixin and other ERM proteins maintain cell shape, growth, and motility. In the nervous system, radixin has been shown to prevent neurodegeneration and axonal growth. The activation of radixin is through phosphorylation of its conserved threonine residues. Radixin functions in cell signaling pathways by binding to membrane proteins and relaying the cell signals into the cells. Deficiency of radixin has been involved in the pathogenic process of diseases in the central nervous system and diabetic peripheral nerve injury. Moreover, radixin also plays a role in cell growth and drug resistance in multiple cancers. The trials of therapeutic potential through radixin modulation have been accumulating. However, the exact mechanisms underlying the roles of radixin are far from clarification. Radixin plays various roles in cells and is involved in developing neurodegenerative diseases and many types of cancers. Therefore, radixin may be considered a potential target for developing therapeutic strategies for its related diseases. Further elucidation of the function and the cell signaling pathways that are linked to radixin may open the avenue to finding novel therapeutic strategies for diseases in the nervous system and other body systems.

Pan-cancer and single-cell analysis reveal dual roles of lymphocyte activation gene-3 (LAG3) in cancer immunity and prognosis

Lymphocyte activating gene-3 (LAG3) is a distinctive T cell co-receptor that is expressed on the surface of lymphocytes. It plays a special inhibitory immune checkpoint role due to its unique domain and signaling pattern. Our aim is to explore the correlation between LAG3 in cancers and physiological processes related to a range of cancers, as well as build LAG3-related immunity and prognostic models. By comprehensively using of datasets and methods from TCGA, GTE-x and GEO databases, cBioPortal, HPA, Kaplan-Meier Plotter, Spearman, CellMinerTM, we delved deeper into the potential impact of the LAG3 in cancer development. These include expression differences, Localization of tumor cell subsets, immune infiltration, matrix infiltration, gene mutations, DNA methylation, signaling pathways and prognosis. Furthermore, we explored LAG3 interactions with different drugs. LAG3 is highly expressed in ACC (p < 0.001), BRCA (p < 0.001), DLBC (p < 0.001), ESCA (p < 0.001), GBM (p < 0.001), HNSC (p < 0.001), KIRC (p < 0.001), LGG (p < 0.001), LUAD (p < 0.01), LUSC (p < 0.001), PAAD (p < 0.001), PCPG (p < 0.01), SKCM (p < 0.001), STAD (p < 0.001), TGCT (p < 0.001) and THCA (p < 0.05), while lowly expressed in COAD (p < 0.001), LIHC (p < 0.05), OV (p < 0.001), PRAD (p < 0.001), READ (p < 0.001), UCEC (p < 0.001) and UCS (p < 0.001). High expression of LAG3 correlates with longer overall survival (OS) in BLCA (HR = 0.67, p < 0.05), CESC (HR = 0.3, p < 0.001), HNSC (HR = 0.67, p < 0.01), LUSC (HR = 0.71, p < 0.05), OV (HR = 0.65, p < 0.01), STAD (HR = 0.68, p < 0.05), and UCEC (HR = 0.57, p < 0.01). Conversely, in KIRC (HR = 1.85, p < 0.001), KIRP (HR = 2.81, p < 0.001), and THYM (HR = 8.92, p < 0.001), high LAG3 expression corresponds to shorter OS. Comprehensive results for recurrence-free survival (RFS) indicate that LAG3 acts as a protective factor in BLCA, CESC, OV, and UCEC. Moreover, LAG3 is widely expressed in tumor-associated lymphocytes, positively correlating with tumor immune scores and stromal scores, and significantly present in the C2 immune subtype across various tumors. High LAG3 expression correlates with increased immune infiltration. LAG3 shows associations with MSI, TMB, and the MMR system, participating in multiple signaling pathways including the T cell receptor pathway. It also demonstrates positive correlations with sensitivity to eleven different drugs. Unlike traditional inhibitory immune checkpoints, LAG3 exhibits dual roles in clinical and immune prognostication across pan-cancers, making it a significant predictive factor. In some cancers, LAG3 serves as a risk factor, indicating adverse clinical outcomes. Conversely, in BLCA, CESC, OV, and UCEC, LAG3 acts as a protective factor associated with longer patient survival. LAG3 demonstrates strong associations within tumor immunity, participating in a range of immune and inflammatory signaling pathways. Elevated levels of LAG3 are linked not only to T cell exhaustion but also to increased immune infiltration and polarization towards M1 macrophages.

Apoptosis and genotoxicity effects of Zygophyllum album and Suaeda palaestina extracts on Ehrlich solid carcinoma in mice

BackgroundVarious medicinal plants and their bioactive compounds exhibited promising anticancer activities by inducing apoptosis, inhibiting angiogenesis, and modulating several signaling pathways in cancer cells. This study aims to assess whether two medicinal plant extracts have anticancer properties, Suaeda Palaestina and Zygophyllum album.MethodsThis study used Ehrlich solid tumor mice as its in vivo model. We divided male mice into five groups (n = 5 per group). Group I was used as a control for Ehrlich ascites carcinoma (EAC). Groups 2 and 3 were given Z. album extract 180 mg/kg and 360 mg/kg body weight intraperitoneally. Groups 4 and 5 were given the same dose of S. palaestina and treated three times a week for 2 weeks, starting on day 10 after EAC implantation. After 3 weeks, we collected blood samples and thigh skeletal muscle, homogenized them, and processed them for analysis. The results showed that Ehrlich solid rats (EST) treated with low-dose dichloromethane extracts from Z. album and S. palaestina had significantly smaller tumor sizes than the control group. Protein expression levels of p53, caspase 3, and Bcl-2 were quantified by western blotting.ResultsThe extracts from both plants induced the hunger mechanism, leading to increased expression of p53 and caspase 3 and decreased expression of Bcl-2 at the protein level in EST mice treated with Z. album and S. palaestina. In addition, the comet assay indicated that these plants have a genotoxic potential for solid tumor cells. The T3 and T4 levels in EST blood samples revealed that both plants had significantly reduced the concentration of T3 and significantly increased T4 compared to the EST mice untreated group. Furthermore, these results showed that Z. album and S. palaestina had antiproliferative effects in EST mice through apoptosis-mediated genotoxicity.ConclusionsThese findings indicated that S. palaestina and Z. album could be considered potential natural sources of anticancer agents.

Copper Nanoparticles Green-Formulated byCurcuma longa Extract Induce Apoptosis via P53 and STAT3 Signaling Pathways in Bladder Carcinoma Cell.

The study outlines the production of new copper nanoparticles infused with Curcuma longa extract to trigger apoptosis through P53 and signal transducer and activator of transcription 3 (STAT3) signaling pathways in bladder carcinoma cells. The structural characteristics of the nanoparticles that were synthesized were analyzed through various sophisticated methods such as transmission electron microscopy (TEM), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). During the antioxidant evaluation, the IC50 values for copper nanoparticles and butylated hydroxytoluene (BHT) against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals were found to be 116µg/mL and 31µg/mL, respectively. The cells treated with copper nanoparticles underwent evaluation through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay for 48h to determine their anticancer properties on TCCSUP bladder carcinoma cell. The TCCSUP cell line exhibited an IC50 of 290µg/mL when exposed to copper nanoparticles. The viability of malignant cells decreased upon treatment with copper nanoparticles. Furthermore, the copper nanoparticles presence led to a 65-75% increase in cell apoptosis, along with an increase in Bax and cleaved caspase-8 and a decrease in the Bcl-2. Furthermore, the copper nanoparticles presence resulted in the suppression of colony formation. Notably, the molecular pathway analysis in cells treated with copper NPs demonstrated an increase in p53 expression, along with a decrease in the expression of both total and phosphorylated STAT3. This offers that p53 and STAT3 play a crucial role in the biological efficacies induced by the nanoparticles in human carcinoma cells. The data of our research suggest that copper NPs could have significant potential as an anticancer treatment for human bladder carcinoma cells.

Monitoring Calcium-Sensing Receptor (CaSR)-Induced Intracellular Calcium Flux Using an Indo-1 Flow Cytometry Assay.

The calcium-sensing receptor (CaSR) has a critical role in maintaining serum calcium concentrations within the normal physiological range, and mutations in the receptor, or components of its signaling and trafficking pathway, cause disorders of calcium homeostasis. Inactivating mutations cause neonatal severe hyperparathyroidism or familial hypocalciuric hypercalcemia (FHH), while gain-of-function mutations cause autosomal dominant hypocalcemia (ADH). Characterizing the functional impact of mutations of the CaSR, and components of the CaSR-signaling pathway, is clinically important to enable correct diagnoses of FHH and ADH, optimize management, and prevent inappropriate parathyroidectomy or vitamin D supplementation. CaSR signals predominantly by activating the G-alpha subunit-11 to mobilize calcium release from intracellular stores. Thus, measurement of CaSR-induced intracellular calcium (Ca2+i) signaling is the gold standard method to investigate the pathogenicity of CaSR genetic variants. This protocol describes a method to assess CaSR-induced Ca2+I signaling using the Indo-1 calcium indicator dye and flow cytometry. This method has been used to assess multiple genetic variants in CaSR and components of its signaling and trafficking pathway in HEK293 cells.

Interleukin-1 Receptor-Associated Kinase 1 in Cancer Metastasis and Therapeutic Resistance: Mechanistic Insights and Translational Advances.

Interleukin-1 Receptor Associated Kinase 1 (IRAK1) is a serine/threonine kinase that plays a critical role as a signaling transducer of the activated Toll-like receptor (TLR)/Interleukin-1 receptor (IL-1R) signaling pathway in both immune cells and cancer cells. Upon hyperphosphorylation by IRAK4, IRAK1 forms a complex with TRAF6, which results in the eventual activation of the NF-κB and MAPK pathways. IRAK1 can translocate to the nucleus where it phosphorylates STAT3 transcription factor, leading to enhanced IL-10 gene expression. In immune cells, activated IRAK1 coordinates innate immunity against pathogens and mediates inflammatory responses. In cancer cells, IRAK1 is frequently activated, and the activation is linked to the progression and therapeutic resistance of various types of cancers. Consequently, IRAK1 is considered a promising cancer drug target and IRAK1 inhibitors have been developed and evaluated preclinically and clinically. This is a comprehensive review that summarizes the roles of IRAK1 in regulating metastasis-related signaling pathways of importance to cancer cell proliferation, cancer stem cells, and dissemination. This review also covers the significance of IRAK1 in mediating cancer resistance to therapy and the underlying molecular mechanisms, including the evasion of apoptosis and maintenance of an inflammatory tumor microenvironment. Finally, we provide timely updates on the development of IRAK1-targeted therapy for human cancers.

Revealing the molecular mechanism of baohuoside I for the treatment of breast cancer based on network pharmacology and molecular docking

Ethnopharmacological relevanceIn Traditional Chinese Medicine (TCM), there are many prescriptions for treating breast cancer (BC) that utilize the herb Epimedium brevicornum Maxim, which warms and replenishes kidney yang. Baohuoside I (BI) is a flavonoid compound found in Epimedium brevicornum Maxim. As a single glycoside, it is not easily hydrolyzed in the intestine and is typically absorbed as a precursor. As a natural product with potential anti-cancer properties, studies have shown that BI possesses anti-cancer activity and can inhibit the invasion and migration of BC cells. However, its underlying mechanisms remain unclear, thus further research is needed to validate its modern mechanisms for traditional uses. Aim of the studyThis study aimed to explore the regulatory mechanism of BI in the signaling pathways of BC cells through network pharmacology (NP), molecular docking (MD) techniques and cellular experiments. MethodsPotential targets were predicted using public databases, and a protein-protein interaction (PPI) network was constructed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. Key signaling pathways were validated through MD techniques, cellular experiments, RNA interference and Western blot (WB) analysis. ResultsTreatment-associated targets included SRC, MAPK1, HSP90AA1, PIK3CA, TP53, AKT1, and EGFR. GO enrichment, KEGG enrichment analyses, and MD results indicated that BI exerts its anti-breast cancer effects by inhibiting the tyrosine kinase activity of EGFR, as well as through downstream MAPK signaling pathway and PI3K-Akt signaling pathway pathways. In vitro experiments confirmed that BI primarily induce cell apoptosis through the EGFR-mediated MAPK signaling pathway and PI3K-Akt signaling pathway. ConclusionBI can inhibit EGFR activation and promote BC cell apoptosis through the MAPK signaling pathway and PI3K-Akt signaling pathway, thereby exerting therapeutic effects on BC. This study not only provides experimental evidence for the accuracy of NP but also offers an effective approach for rational utilization of Baohuoside I-like flavonoid compounds as anti-breast cancer drugs.

MiR-27 and MiR-145 mediate neural differentiation signaling pathways in dental pulp stem cells

MiR-27 and MiR-145 mediate neural differentiation signaling pathways in dental pulp stem cells

Synergistic Effect of Some Molecular Biomarkers in The Development of Preeclampsia and Abortion in Pregnant Women Suffer from Toxoplasmosis

The current study summarized the effect of toxoplasmosis, which is caused by parasitic infection with protozoan known as Toxoplasma gondii, on pregnant women who suffer from repeated miscarriages, especially in the first trimester of pregnancy, this research documented the reduction of sex hormones values in healthy pregnant women, association with down ROP16 regulation(T.gondii-I virulence factor). While the average of the same parameters was increased in pregnant women who suffered from toxoplasmosis, which in turn led to inhibition of the transcription factor NFKB in parasite`s infected women, and inhibition of the patient's immune response. On the other hand, both of ROP16 and NFKB genes play a critical role in an increase of miR146 transcription, it consider a significant factor that activate epigenetic effect perhaps play role in reducing of host's immune system. At the end the placental cell signaling pathway was modified and increased atrophy of placental trophoblast with association of serious complications led at the end to emergence of early abortion.

Lymphocytes Change Their Phenotype and Function in Systemic Lupus Erythematosus and Lupus Nephritis.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease, characterized by considerable changes in peripheral lymphocyte structure and function, that plays a critical role in commencing and reviving the inflammatory and immune signaling pathways. In healthy individuals, B lymphocytes have a major role in guiding and directing defense mechanisms against pathogens. Certain changes in B lymphocyte phenotype, including alterations in surface and endosomal receptors, occur in the presence of SLE and lead to dysregulation of peripheral B lymphocyte subpopulations. Functional changes are characterized by loss of self-tolerance, intra- and extrafollicular activation, and increased cytokine and autoantibody production. T lymphocytes seem to have a supporting, rather than a leading, role in the disease pathogenesis. Substantial aberrations in peripheral T lymphocyte subsets are evident, and include a reduction of cytotoxic, regulatory, and advanced differentiated subtypes, together with an increase of activated and autoreactive forms and abnormalities in follicular T cells. Up-regulated subpopulations, such as central and effector memory T cells, produce pre-inflammatory cytokines, activate B lymphocytes, and stimulate cell signaling pathways. This review explores the pivotal roles of B and T lymphocytes in the pathogenesis of SLE and Lupus Nephritis, emphasizing the multifaceted mechanisms and interactions and their phenotypic and functional dysregulations.

Pleiotrophin Activates cMet- and mTORC1-Dependent Protein Synthesis through PTPRZ1-The Role of ανβ3 Integrin.

Pleiotrophin (PTN) is a secreted factor that regulates endothelial cell migration through protein tyrosine phosphatase receptor zeta 1 (PTPRZ1) and αvβ3 integrin. Genetic deletion of Ptprz1 results in enhanced endothelial cell proliferation and migration, due to the decreased expression of β3 integrin and the subsequent, enhanced cMet phosphorylation. In the present study, we investigated the effect of PTN and PTPRZ1 on activating the mTORC1 kinase and protein synthesis and identified part of the implicated signaling pathway in endothelial cells. PTN or genetic deletion of Ptprz1 activates protein synthesis in a mTORC1-dependent manner, as shown by the enhanced phosphorylation of the mTORC1-downstream targets ribosomal protein S6 kinase 1 (SK61) and 4E-binding protein 1 (4EBP1) and the upregulation of HIF-1α. The cMet tyrosine kinase inhibitor crizotinib abolishes the stimulatory effects of PTN or PTPRZ1 deletion on mTORC1 activation and protein synthesis, suggesting that mTORC1 activation is downstream of cMet. The mTORC1 inhibitor rapamycin abolishes the stimulatory effect of PTN or PTPRZ1 deletion on endothelial cell migration, suggesting that mTORC1 is involved in the PTN/PTPRZ1-dependent cell migration. The αvβ3 integrin blocking antibody LM609 and the peptide PTN112-136, both known to bind to ανβ3 and inhibit PTN-induced endothelial cell migration, increase cMet phosphorylation and activate mTORC1, suggesting that cMet and mTORC1 activation are required but are not sufficient to stimulate cell migration. Overall, our data highlight novel aspects of the signaling pathway downstream of the PTN/PTPRZ1 axis that regulates endothelial cell functions.

Super-resolution imaging reveals the role of DDR1 cluster in NSCLC proliferation

Discoidin domain receptor 1 (DDR1), a transmembrane protein, is crucial in tumor development. Prior studies have demonstrated a significant correlation between protein cluster distribution on the cell membrane and tumor evolution. However, the precise spatial distribution characteristics of DDR1 on cell membranes and their impact on tumor development remain unclear. In this study, we conducted gene expression analysis to investigate DDR1 expression in non-small cell lung cancer (NSCLC) and its association with patient prognosis. We also employed direct stochastic optical reconstruction microscopy (dSTORM) imaging to examine DDR1's spatial distribution in NSCLC cells and tissues. Our findings indicate that DDR1 forms larger, tighter, and more abundant clusters in cancer cells and tissues compared to their normal counterparts. Notably, we observed that the enhanced aggregation of DDR1 clusters increased the likelihood of interaction with SRC, thereby activating the SRC-STAT3 signaling pathway in NSCLC cells and promoting cell proliferation. This study provides novel insights into the role of DDR1 aggregation in tumor proliferation, confirms DDR1 as a potential tumor marker, and serves as a valuable resource for future drug development.

The β2-adrenergic biased agonist nebivolol inhibits the development of Th17 and the response of memory Th17 cells in an NF-κB-dependent manner.

Adrenergic receptors regulate metabolic, cardiovascular, and immunological functions in response to the sympathetic nervous system. The effect of β2-adrenergic receptor (AR) as a high expression receptor on different subpopulations of T cells is complex and varies depending on the type of ligand and context. While traditional β2-AR agonists generally suppress T cells, they potentially enhance IL-17A production by Th17 cells. The effects of pharmacological drugs that count as biased agonists of AR like nebivolol are not completely understood. We investigated the impact of nebivolol on human memory CD4+ T (Th1, Th2, Th17) cells and polarized naive Th17 cells, highlighting its potential for IL-17A suppression via a non-canonical β2-AR cell signaling pathway. The effects of nebivolol were tested on healthy human peripheral blood mononuclear cells, purified memory Th cells, and polarized naive Th17 cells activated with anti-CD3/anti-CD28/anti-CD2 ImmunoCult reagent. IFN-γ, IL-4, and IL-17A, which are primarily derived from Th1, Th2, and Th17 cells, respectively, were quantified by ELISA and flow cytometry. IL-10 was measured by ELISA. Gene expression of RORC, ADRB1, ADRB2, and ADRB3 was evaluated by qPCR. The ADRB2 gene was knocked out in memory Th cells using CRISPR/Cas9. Protein expression of phosphorylated serine133-CREB and phosphorylated NF-κB p65 was assessed by Western blot. Proliferation was assessed by fluorescent dye loading and flow cytometry. Nebivolol treatment decreased IL-17A and IFN-γ secretion by activated memory Th cells and elevated IL-4 levels. Nebivolol reduced the proportion of IL-17A+ Th cells and downregulated RORC expression. Unlike the β2-AR agonist terbutaline, nebivolol inhibited the shift of naive CD4+ T cells toward the Th17 phenotype. IL-10 and the proliferation index remained unchanged. Nebivolol-treated β2-knockout memory Th cells showed significant inhibition of β2-AR-mediated signaling, evidenced by the absence of IL-17A suppression compared to controls. Phosphorylation of the NF-κB p65 subunit was inhibited by nebivolol, but CREB phosphorylation was not changed, suggesting a selective transcriptional control. The findings demonstrate that nebivolol acts through a β2-AR-mediated signaling pathway, as a distinctive anti-inflammatory agent capable of selectively shifting Th17 cells and suppressing the phosphorylation of NF-κB. This highlights nebivolol's potential for therapeutic interventions in chronic autoimmune conditions with elevated IL-17A levels.

Changes in gene expression profile of normal human fibroblasts on P(VDF-TrFE) scaffolds highly doped with Fe3O4-CA nanoparticles under alternating magnetic field stimulation

The design of novel hybrid magnetoactive scaffolds based on biocompatible piezopolymers and magnetic nanoparticles is of interest for medicine, mainly for tissue regeneration, because application of an external either static or alternating magnetic field to cells that settled on a magnetoactive scaffold offers an opportunity for remote control of cellular functions. This study describes fabrication of electrospun magnetoactive poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] scaffolds highly doped with 20 wt% of magnetite nanoparticles modified with citric acid (Fe3O4-CA). The electrospun P(VDF-TrFE)/Fe3O4-CA scaffolds have defect-free morphology with a fiber diameter of approximately 1 μm and contain both an electroactive β-phase (predominantly) and a lesser amount of an γ-phase. A high content of uniformly distributed Fe3O4-CA nanoparticles within P(VDF-TrFE) fibrous scaffolds resulted in a high saturation magnetization of 12.1 emu/g and ferrimagnetic behavior of the composite P(VDF-TrFE)/Fe3O4-CA scaffolds. They were proved to be biocompatible with normal human cells: normal human fibroblasts and human mesenchymal stem cells adhered to the scaffold and retained their viability. According to high-throughput RNA-sequencing data, the adhesion of fibroblasts to the scaffolds upregulated genes related to key stages of tissue regeneration such as coagulation (genes THBD and SERPINB2) and wound healing (IL24, PDGFB, F3, and PLAU) and affected TGFβ, BMP, and Wnt signaling pathways. Alternating-magnetic-field exposure of the magnetoactive P(VDF-TrFE)/Fe3O4-CA scaffolds with fibroblasts settled on the surface activated extracellular and intracellular cell signaling pathways.

Repurposing of c-MET Inhibitor Tivantinib Inhibits Pediatric Neuroblastoma Cellular Growth

Background: Dysregulation of receptor tyrosine kinase c-MET is known to promote tumor development by stimulating oncogenic signaling pathways in different cancers, including pediatric neuroblastoma (NB). NB is an extracranial solid pediatric cancer that accounts for almost 15% of all pediatric cancer-related deaths, with less than a 50% long-term survival rate. Results: In this study, we analyzed a large cohort of primary NB patient data and revealed that high MET expression strongly correlates with poor overall survival, disease progression, relapse, and high MYCN levels in NB patients. To determine the effects of c-MET in NB, we repurposed a small molecule inhibitor, tivantinib, and found that c-MET inhibition significantly inhibits NB cellular growth. Tivantinib significantly blocks NB cell proliferation and 3D spheroid tumor formation and growth in different MYCN-amplified and MYCN-non-amplified NB cell lines. Furthermore, tivantinib blocks the cell cycle at the G2/M phase transition and induces apoptosis in different NB cell lines. As expected, c-MET inhibition by tivantinib inhibits the expression of multiple genes in PI3K, STAT, and Ras cell signaling pathways. Conclusions: Overall, our data indicate that c-MET directly regulates NB growth and 3D spheroid growth, and c-MET inhibition by tivantinib may be an effective therapeutic approach for high-risk NB. Further developing c-MET targeted therapeutic approaches and combining them with current therapies may pave the way for effectively translating novel therapies for NB and other c-MET-driven cancers.

The syntaxin-binding protein STXBP5 regulates progerin expression.

Hutchinson-Gilfor progeria syndrome (HGPS) is caused by a mutation in Lamin A resulting in the production of a protein called progerin. The accumulation of progerin induces inflammation, cellular senescence and activation of the P53 pathway. In this study, through public dataset analysis, we identified Syntaxin Binding Protein 5 (STXBP5) as an influencing factor of progerin expression. STXBP5 overexpression accelerated the onset of senescence, while STXBP5 deletion suppressed progerin expression, delayed senility, and decreased the expression of senescence-related factors. STXBP5 and progerin have synergistic effects and a protein-protein interaction. Through bioinformatics analysis, we found that STXBP5 affects ageing-related signalling pathways such as the mitogen-activated protein kinase (MAPK) pathway, the hippo pathway and the interleukin 17 (IL17) signalling pathway in progerin-expressing cells. In addition, STXBP5 overexpression induced changes in transposable elements (TEs), such as the human endogenous retrovirus H internal coding sequence (HERVH-int) changes. Our protein coimmunoprecipitation (Co-IP) results indicated that STXBP5 bound directly to progerin. Therefore, decreasing STXBP5 expression is a potential new therapeutic strategy for treating ageing-related phenotypes in patients with HGPS.

Gaining or cutting SLAC: the evolution of plant guard cell signalling pathways.

The evolution of adjustable stomatal pores, enabling CO2 acquisition, was one of the most significant events in the development of life on land. Here, we investigate how the guard cell signalling pathways that regulate stomatal movements evolved. We compare fern and angiosperm guard cell transcriptomes and physiological responses, and examine the functionality of ion channels from diverse plant species. We find that, despite conserved expression in guard cells, fern anion channels from the SLAC/SLAH family are not activated by the same abscisic acid (ABA) pathways that provoke stomatal closure in angiosperms. Accordingly, we find an insensitivity of fern stomata to ABA. Moreover, our analysis points to a complex evolutionary history, featuring multiple gains and/or losses of SLAC activation mechanisms, as these channels were recruited to a role in stomatal closure. Our results show that the guard cells of flowering and nonflowering plants share similar core features, with lineage-specific and ecological niche-related adaptations, likely underlying differences in behaviour.

Modulatory Effects of Chalcone Thio-Derivatives on NF-κB and STAT3 Signaling Pathways in Hepatocellular Carcinoma Cells: A Study on Selected Active Compounds.

Our previous studies demonstrated the modulatory effects of new synthetic thio-chalcone derivatives in dishes on the Nrf2, NF-κB, and STAT3 signaling pathways in colon cancer cells. This study aimed to evaluate the effect of four selected active chalcone thio-derivatives on the NF-κB and STAT3 signaling pathways involved in inflammatory processes and cell proliferation in human liver cancer cells. Cell survival was assessed for cancer (HepG2) and normal (THLE-2) cell lines. Activation of NF-κB and STAT3 signaling pathways and the expression of proteins controlled by these pathways were estimated by Western blot, and qRT-PCR assessed the expression of NF-κB and STAT3 target genes. We also evaluated the impact on the selected kinases responsible for the phosphorylation of the studied transcription factors by MagneticBead-Based Multiplex Immunoassay. Among the thio-derivatives tested, especially derivatives 1 and 5, there was an impact on cell viability, cell cycle, apoptosis, and activation of NF-κB and STAT3 pathways in hepatocellular carcinoma (HCC), which confirms the possibilities of using them in combinatorial molecular targeted therapy of HCC. The tested synthetic thio-chalcones exhibit anticancer activity by initiating proapoptotic processes in HCC while showing low toxicity to non-cancerous cells. These findings confirm the possibility of using chalcone thio-derivatives in molecularly targeted combination therapy for HCC.

8649 Ablation of Leptin Receptors in Somatotropes Impacts Transcriptomic Plasticity in the Pou1f1 Lineage of Female Pituitary Cells

Abstract Disclosure: T.K. Miles: None. A.K. Odle: None. S. Byrum: None. A. Lagasse: None. A. Haney: None. V.G. Ortega: None. A. Herdman: None. M.C. MacNicol: None. A.M. MacNicol: None. G.V. Childs: None. Anterior pituitary somatotropes produce growth hormone (GH) to optimize body composition, receiving tropic signals from leptin about the metabolic state. When leptin receptors are ablated in somatotropes, GH proteins, serum GH and GHRH receptors are reduced. Unexpectedly, POU1F1, Prolactin, and TSH-beta proteins are also reduced in pituitaries of Somatotrope LEPR-null females (mutants), suggesting a tropic role for leptin in differentiation. To test this hypothesis, single cell RNA-seq analysis compared the pituitary transcriptome of 6-month-old control and mutant female mice housed under thermoneutral conditions (28°C). Following scRNA-seq, cells were clustered computationally with the use of Seurat; all cell types were identified in separate UMAP clusters. Mutants showed increases in cell numbers in somatotrope (4.7X) and Pou1f1 (5.7x) clusters, but no change in thyrotrope or lactotrope clusters. In LEPR-null female somatotropes, the 516 differentially expressed genes (DEGs; adj p&amp;lt;0.05) included upregulated Pomc, Prl, Lhb, Tshb and Cga (Log2FC+0.5-1.7) and downregulated Pou1f1, Ghrhr, and Gh (Log2FC -0.5—1.5). In the lactotrope cluster from mutants, Pomc, Cga, and Gh were upregulated (Log2FC+1.1-1.5) and Pou1f1 and Prl were downregulated. The thyrotrope cluster was unchanged. Prl, Pomc, and Gh were upregulated in the Pou1f1 cluster. The down regulation of Gh, Pou1f1, and Ghrhr in somatotropes and Prl in lactotropes correlates with the lower serum levels of GH and Prl in mutant females. However, the upregulated DEGs do not correlate with increased secretory activity suggesting that the multihormonal cells are not fully functional. This was confirmed with Ingenuity Pathway Analysis (IPA) showing downregulation of canonical pathways involved in secretion in mutant somatotropes. Unexpectedly, mutant females exposed to a HFD (60% fat) for 16 weeks (+16.6g) showed a reversal of the changes in somatotrope cell numbers and multihormonal expression seen in control fed mutants. The increase in genes belonging to IPA canonical cytoplasmic translation pathways in mutant somatotropes were also completely reversed following a HFD. Furthermore, the downregulated secretory/signaling pathways seen in control fed mutant female somatotropes and lactotropes (endocytosis, vesicle transport, Gaq, GnRH) were upregulated modestly following a HFD. The high serum leptin in the HFD fed mutant mice may activate signaling pathways in cells still expressing LEPR. Collectively, these results confirm a role for leptin in maintaining differentiated somatotropes. They also suggest that leptin may limit expansion of multihormonal progenitor cells. The decreased multihormonal expression and protein synthesis in lactotrope clusters from mutant mice exposed to a HFD are also seen in lactotropes from control mice on a HFD, which suggests that a HFD may compromise pituitary plasticity. Presentation: 6/3/2024

The molecular mechanisms of Caulophyllum robustum Maxim extract inhibition by regulating FAK/PI3K signaling pathway in gastric cancer HGC-27 cells

Ethnopharmacological relevanceCaulophyllumrobustum Maxim extract (CRME), as recorded in traditional Chinese medicine, has the function of dispelling Feng, regulating Qi and dredging collaterals, promoting blood circulation and regulating menstruation, gingering up and relieving pain, clearing heat simultaneously detoxifying, lowering blood pressure and hemostasis. CRME is often used as Chinese materia medica preparation for rheumatoid arthritis, traumatic injury, irregular menstruation, abdominal pain, and hypertension treatment. Since gastric cancer (GC) existed as a health problem of human over the years, we are committed to the development of potential components of Chinese herbal medicine curing cancer, and we found CRME is expected to be one of the effective anti-tumor traditional Chinese medicine preparations. Aims of the studyTo investigate the molecular mechanisms of CRME anticancer effects and the potential links between CRME and FAK. Materials and methodsCaulophyllumrobustum Maxim was extracted to obtain CRME, high-performance liquid chromatography (HPLC) was used for qualitative analysis. Information about CRME was collected from traditional Chinese medicine records and local surveys unpublished internationally. Series of cellular function experiments were applied to detect cell proliferation, migration, apoptosis, autophagy, cell cycle, angiogenesis. The xenograft model is employed in vivo. ResultsCRME can significantly inhibit HGC-27 cells on proliferation, migration and angiogenic capacity. Xenograft model indicated CRME inhibited cell proliferation in vivo. Annexin V-FITC/PI double staining assay and PI single staining assay depicted that CRME induces cell apoptosis, and arrests cell cycle at G0/G1 phase. AO (acridine orange) staining assay showed that CRME promoted autophagosome formation and inhibited autophagic flow. HPLC indicated Cauloside A and Cauloside C are components of CRME. Western blot indicated that FAK/PI3K signaling pathway is critical in the inhibition of CRME on HGC-27 cells. ConclusionsThe anti-tumor components of CRME, Cauloside A and Cauloside C, inhibited tumor progression in HGC-27 cells. This inhibition is achieved by decreasing the phosphorylation levels of FAK, thereby modulating PI3K/AKT signaling pathway.