BACKGROUND: Temozolomide (TMZ) resistance is a significant challenge in treating glioblastoma (GBM). Collagen remodeling has been shown to be a critical factor for therapy resistance in other cancers. This study aimed to investigate the mechanism of TMZ chemoresistance by GBM cells reprogramming collagens. METHODS: Key extracellular matrix components, including collagens, were examined in paired primary and recurrent GBM samples as well as in TMZ-treated spontaneous and grafted GBM murine models. Human GBM cell lines (U251, TS667) and mouse primary GBM cells were used for in vitro studies. RNA-sequencing analysis, chromatin immunoprecipitation, immunoprecipitation-mass spectrometry, and co-immunoprecipitation assays were conducted to explore the mechanisms involved in collagen accumulation. A series of in vitro and in vivo experiments were designed to assess the role of the collagen regulators prolyl 4-hydroxylase subunit alpha 1 (P4HA1) and yes-associated protein (YAP) in sensitizing GBM cells to TMZ. RESULTS: This study revealed that TMZ exposure significantly elevated collagen type I (COL I) expression in both GBM patients and murine models. Collagen accumulation sustained GBM cell survival under TMZ-induced stress, contributing to enhanced TMZ resistance. Mechanistically, P4HA1 directly binded to and hydroxylated YAP, preventing ubiquitination-mediated YAP degradation. Stabilized YAP robustly drove collagen type I alpha 1 ( COL1A1) transcription, leading to increased collagen deposition. Disruption of the P4HA1-YAP axis effectively reduced COL I deposition, sensitized GBM cells to TMZ, and significantly improved mouse survival. CONCLUSION P4HA1 maintained YAP-mediated COL1A1 transcription, leading to collagen accumulation and promoting chemoresistance in GBM.
Temozolomide ; Humans ; Glioblastoma/drug therapy* ; Animals ; Mice ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; YAP-Signaling Proteins ; Hydroxylation ; Dacarbazine/pharmacology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Transcription Factors/metabolism* ; Collagen/biosynthesis* ; Collagen Type I/metabolism* ; Prolyl Hydroxylases/metabolism* ; Antineoplastic Agents, Alkylating/therapeutic use*

Ginsenoside Rg_2(GRg2) is a triterpenoid compound found in Panax notoginseng. This study explored its effects and mechanisms on diabetic retinopathy and angiogenesis. The study employed endothelial cell models induced by glucose or vascular endothelial growth factor(VEGF), the chorioallantoic membrane(CAM) model, the oxygen-induced retinopathy(OIR) mouse model, and the db/db mouse model to evaluate the therapeutic effects of GRg2 on diabetic retinopathy and angiogenesis. Transwell assays and endothelial tube formation experiments were conducted to assess cell migration and tube formation, while vascular area measurements were applied to detect angiogenesis. The impact of GRg2 on the retinal structure and function of db/db mice was evaluated through retinal thickness and electroretinogram(ERG) analyses. The study investigated the mechanisms of GRg2 by analyzing the activation of Yes-associated protein(YAP) and Toll-like receptors(TLRs) pathways. The results indicated that GRg2 significantly reduced cell migration numbers and tube formation lengths in vitro. In the CAM model, GRg2 exhibited a dose-dependent decrease in the vascular area ratio. In the OIR model, GRg2 notably decreased the avascular and neovascular areas, ameliorating retinal structural disarray. In the db/db mouse model, GRg2 increased the total retinal thickness and enhanced the amplitudes of the a-wave, b-wave, and oscillatory potentials(OPs) in the ERG, improving retinal structural disarray. Transcriptomic analysis revealed that the TLR signaling pathway was significantly down-regulated following YAP knockdown, with PCR results consistent with the transcriptome sequencing findings. Concurrently, GRg2 downregulated the expression of Toll-like receptor 4(TLR4), TNF receptor-associated factor 6(TRAF6), and nuclear factor-kappaB(NF-κB) proteins in high-glucose-induced endothelial cells. Collectively, GRg2 inhibits cell migration and tube formation and significantly reduces angiogenesis in CAM and OIR models, improving retinal structure and function in db/db mice, with its pharmacological mechanism likely involving the down-regulation of YAP expression.
Animals ; Ginsenosides/pharmacology* ; Diabetic Retinopathy/physiopathology* ; Mice ; YAP-Signaling Proteins ; Humans ; Male ; Signal Transduction/drug effects* ; Cell Movement/drug effects* ; Adaptor Proteins, Signal Transducing/genetics* ; Mice, Inbred C57BL ; Neovascularization, Pathologic/metabolism* ; Drugs, Chinese Herbal/administration & dosage* ; Panax notoginseng/chemistry* ; Endothelial Cells/metabolism* ; Transcription Factors/genetics* ; Angiogenesis

This study aims to explore the mechanism of Buyang Huanwu Decoction(BHD) in promoting angiogenesis after oxygen-glucose deprivation/reoxygenation(OGD/R) of mouse brain microvascular endothelial cell line(brain-derived Endothelial cells.3, bEnd.3) based on the caveolin-1(Cav1)/Yes-associated protein 1(YAP1)/hypoxia-inducible factor-1α(HIF-1α) signaling pathway. Ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to analyze the blood components of BHD. The cell counting kit-8(CCK-8) method was used to detect the optimal intervention concentration of drug-containing serum of BHD after OGD/R injury of bEnd.3. The lentiviral transfection method was used to construct a Cav1 silent stable strain, and Western blot and polymerase chain reaction(PCR) methods were used to verify the silencing efficiency. The control bEnd.3 cells were divided into a normal group(sh-NC control group), an OGD/R model + blank serum group(sh-NC OGD/R group), and an OGD/R model + drug-containing serum group(sh-NC BHD group). Cav1 silent cells were divided into an OGD/R model + blank serum group(sh-Cav1 OGD/R group) and an OGD/R model + drug-containing serum group(sh-Cav1 BHD group). The cell survival rate was detected by the CCK-8 method. The cell migration ability was detected by a cell migration assay. The lumen formation ability was detected by an angiogenesis assay. The apoptosis rate was detected by flow cytometry, and the expression of YAP1/HIF-1α signaling pathway-related proteins in each group was detected by Western blot. Finally, co-immunoprecipitation was used to verify the interaction between YAP1 and HIF-1α. The results showed astragaloside Ⅳ, formononetin, ferulic acid, and albiflorin in BHD can all enter the blood. The drug-containing serum of BHD at a mass fraction of 10% may be the optimal intervention concentration for OGD/R-induced injury of bEnd.3 cells. Compared with the sh-NC control group, the sh-NC OGD/R group showed significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, significantly increased cell apoptotic rate, significantly lowered phosphorylation level of YAP1 at S127 site, and significantly elevated nuclear displacement level of YAP1 and protein expression of HIF-1α, vascular endothelial growth factor(VEGF), and vascular endothelial growth factor receptor 2(VEGFR2). Compared with the same type of OGD/R group, the sh-NC BHD group and sh-Cav1 BHD group had significantly increased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly decreased cell apoptotic rate, a further decreased phosphorylation level of YAP1 at S127 site, and significantly increased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. Compared with the sh-NC OGD/R group, the sh-Cav1 OGD/R group exhibited significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly increased cell apoptotic rate, a significantly increased phosphorylation level of YAP1 at S127 site, and significantly decreased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. Compared with the sh-NC BHD group, the sh-Cav1 BHD group showed significantly decreased cell survival rate, cell migration rate, mesh number, node number, and lumen length, a significantly increased cell apoptotic rate, a significantly increased phosphorylation level of YAP1 at the S127 site, and significantly decreased nuclear displacement level of YAP1 and protein expression of HIF-1α, VEGF, and VEGFR2. YAP1 protein was present in the protein complex precipitated by the HIF-1α antibody, and HIF-1α protein was also present in the protein complex precipitated by the YAP1 antibody. The results confirmed that the drug-containing serum of BHD can increase the activity of YAP1/HIF-1α pathway in bEnd.3 cells damaged by OGD/R through Cav1 and promote angiogenesis in vitro.
Drugs, Chinese Herbal/pharmacology* ; Animals ; Mice ; Signal Transduction/drug effects* ; Glucose/metabolism* ; Caveolin 1/genetics* ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; YAP-Signaling Proteins ; Oxygen/metabolism* ; Endothelial Cells/metabolism* ; Cell Line ; Adaptor Proteins, Signal Transducing/genetics* ; Neovascularization, Physiologic/drug effects* ; Cell Hypoxia/drug effects* ; Angiogenesis

Osteoarthritis (OA) is the most common degenerative joint disease. Its pathological process is related to inflammatory response, chondrocyte apoptosis, and cartilage degeneration. Hippo-yes-associate protein(YAP) signaling pathway plays an important role in mediating organ size and tissue homeostasis. In recent years, the key effector protein YAP in the Hippo-YAP pathway has become a research hotspot in osteoarthritis. This article introduces the activation process of Hippo-YAP signaling pathway and the biological role of YAP. It reviews the progress of YAP in regulating osteoarthritis by influencing the proliferation and differentiation of mesenchymal stem cells and the proliferation, differentiation, and apoptosis of articular chondrocytes. It analyzed the problems encountered in YAP research in OA, introduces the research potential of YAP in other orthopedic diseases, and provides new ideas for subsequent research in Osteoarthritis.
Osteoarthritis/metabolism* ; Humans ; Signal Transduction ; Protein Serine-Threonine Kinases/physiology* ; Hippo Signaling Pathway ; YAP-Signaling Proteins ; Adaptor Proteins, Signal Transducing/physiology* ; Animals ; Transcription Factors ; Chondrocytes/cytology* ; Cell Cycle Proteins

Despite the groundbreaking advances in cancer immunotherapy achieved by immune checkpoint inhibitors (ICIs), their efficacy remains limited by the immunosuppressive tumor microenvironment (TME). Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), key effectors of the Hippo signaling pathway, play pivotal roles in tumor immune evasion. They directly regulate the expression of immune checkpoints, mediate the formation of an immunosuppressive microenvironment, inhibit T cell function, and interact with other signaling pathways to promote immune escape. Diverse strategies targeting YAP/TAZ have been developed, including direct inhibition, modulation of upstream regulators, and suppression of downstream target genes. Preclinical studies have demonstrated that combining YAP/TAZ inhibition with ICIs significantly enhances therapeutic efficacy across various tumor models. This review summarizes recent advances in understanding the role of YAP/TAZ in immune evasion within the TME and explores the potential of targeting this pathway to improve immunotherapy outcomes. Furthermore, it discusses the translational value of combination therapies based on YAP/TAZ inhibition, providing a theoretical framework and practical guidance for the development of innovative immunotherapeutic strategies and precision medicine approaches.
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Humans ; Immunotherapy/methods* ; Neoplasms/metabolism* ; Signal Transduction/drug effects* ; Adaptor Proteins, Signal Transducing/immunology* ; Animals ; Transcriptional Coactivator with PDZ-Binding Motif Proteins ; Transcription Factors/immunology* ; YAP-Signaling Proteins ; Tumor Microenvironment

Hippo signaling is a highly conserved pathway central to diverse cellular processes. Dysregulation of this pathway not only leads to developmental abnormalities but is also closely related to the occurrence and progression of various cancers. Recent studies have uncovered that, in addition to the classical signaling cascade regulation, biomolecular condensates formed via phase separation play a key role in the spatiotemporal regulation of Hippo signaling. In this review, we provide a summary of the latest research progress on the regulation of the Hippo signaling pathway by phase separation, with a particular focus on transcriptional activation mediated by Yes-associated protein (YAP)/transcriptional coactivator with post-synaptic density-95, disks-large, and zonula occludens-1 (PDZ)-binding domain (TAZ) condensates. Furthermore, we discuss the utility of chemical crosslinking combined with mass spectrometry to analyze the TAZ condensate interactome and examine the role of the protein fused in sarcoma (FUS) in modulating the biophysical properties of TAZ condensates, which in turn influence their transcriptional activity and pro-tumorigenic functions. These insights not only advance our understanding of Hippo signaling but also offer new perspectives for therapeutic interventions targeting diseases linked to dysregulated YAP/TAZ activity.
Humans ; Signal Transduction ; Hippo Signaling Pathway ; Protein Serine-Threonine Kinases/physiology* ; Animals ; Biomolecular Condensates/metabolism* ; Transcription Factors/metabolism* ; YAP-Signaling Proteins ; Adaptor Proteins, Signal Transducing/metabolism* ; Neoplasms ; Transcriptional Activation ; Intracellular Signaling Peptides and Proteins/metabolism*

OBJECTIVES: To investigate the inhibitory effect of Zheng GanDecoction (ZGF) on tumor progression in a rat model of diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) and explore the possible mechanism. METHODS: Seventy SD rats were subjected to regular intraperitoneal injections of DEN (50 mg/kg) for 12 weeks to induce HCC tumorigenesis, with another 10 rats receiving saline injections as the normal control. After successful modeling, the rats were randomized into 5 groups (n=10) for daily treatment with distilled water ( model group), Huaier Granules (4 g/kg; positive control group), or ZGF at low, medium, and high doses (2, 4, and 8 g/kg, respectively) via gavage for 17 weeks. Body weight changes of the rats were monitored, and after completion of the treatments, the rats were euthanized for measurement of liver, spleen and thymus indices and morphological and histopathological examinations of the liver tissues using HE staining. The expressions of YAP, p-YAP, MST1, LATS1 and p-LATS1 in the liver tissues were detected using immunohistochemistry and Western blotting. RESULTS: Compared with the normal control rats, the rat models with DEN-induced HCC exhibited much poorer general condition with a significantly reduced survival rate, increased body weight and liver and spleen indices, and a lowered thymus index. ZGF treatment obviously reduced liver and spleen indices, increased the thymus index, and improved pathologies of the liver tissues of the rat models. Immunohistochemistry and Western blotting showed a dose-dependent reduction of YAP expression and an increment of p-YAP expression in ZGF-treated rats, which also exhibited significantly upregulated hepatic expressions of MST1, LATS1 and p-LATS1. CONCLUSIONS ZGF inhibits DEN-induced HCC in rats by activating the Hippo/YAP pathway via upregulating MST1 and LATS1 expression, which promotes YAP phosphorylation and degradation to suppress proliferation and induce apoptosis of the tumor cells.
Animals ; Drugs, Chinese Herbal/pharmacology* ; Diethylnitrosamine ; Rats, Sprague-Dawley ; Rats ; Signal Transduction/drug effects* ; Protein Serine-Threonine Kinases/metabolism* ; Carcinoma, Hepatocellular/drug therapy* ; YAP-Signaling Proteins ; Liver Neoplasms/drug therapy* ; Hippo Signaling Pathway ; Male ; Liver Neoplasms, Experimental/metabolism* ; Transcription Factors/metabolism* ; Adaptor Proteins, Signal Transducing/metabolism*

Yes-associated protein (YAP), the key transcriptional co-factor and downstream effector of the Hippo pathway, has emerged as one of the primary regulators of neural as well as glial cells. It has been detected in various glial cell types, including Schwann cells and olfactory ensheathing cells in the peripheral nervous system, as well as radial glial cells, ependymal cells, Bergmann glia, retinal Müller cells, astrocytes, oligodendrocytes, and microglia in the central nervous system. With the development of neuroscience, understanding the functions of YAP in the physiological or pathological processes of glia is advancing. In this review, we aim to summarize the roles and underlying mechanisms of YAP in glia and glia-related neurological diseases in an integrated perspective.
Humans ; Animals ; Neuroglia/metabolism* ; Signal Transduction/physiology* ; YAP-Signaling Proteins ; Nerve Regeneration/physiology* ; Nervous System Diseases/metabolism* ; Adaptor Proteins, Signal Transducing/metabolism*

Objective: To explore the mechanism of Doublecortin-like kinase 1 (DCLK1) in promoting cell migration, invasion and proliferation in pancreatic cancer. Methods: The correlation between DCLK1 and Hippo pathway was analyzed using TCGA and GTEx databases and confirmed by fluorescence staining of pancreatic cancer tissue microarrays. At the cellular level, immunofluorescence staining of cell crawls and western blot assays were performed to clarify whether DCLK1 regulates yes associated protein1 (YAP1), a downstream effector of the Hippo pathway. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to analyze the expressions of YAP1 binding transcription factor TEA-DNA binding proteins (TEAD) and downstream malignant behavior-promoting molecules CYR61, EDN1, AREG, and CTGF. Transwell test of the DCLK1-overexpressing cells treated with the Hippo pathway inhibitor Verteporfin was used to examine whether the malignant behavior-promoting ability was blocked. Analysis of changes in the proliferation index of experimental cells used real-time label-free cells. Results: TCGA combined with GTEx data analysis showed that the expressions of DCLK1 and YAP1 molecules in pancreatic cancer tissues were significantly higher than those in adjacent tissues (P<0.05). Moreover, DCLK1was positively correlated with the expressions of many effectors in the Hippo pathway, including LATS1 (r=0.53, P<0.001), LATS2 (r=0.34, P<0.001), MOB1B (r=0.40, P<0.001). In addition, the tissue microarray of pancreatic cancer patients was stained with multicolor fluorescence, indicated that the high expression of DCLK1 in pancreatic cancer patients was accompanied by the up-regulated expression of YAP1. The expression of DCLK1 in pancreatic cancer cell lines was analyzed by the CCLE database. The results showed that the expression of DCLK1 in AsPC-1 and PANC-1 cells was low. Thus, we overexpressed DCLK1 in AsPC-1 and PANC-1 cell lines and found that DCLK1 overexpression in pancreatic cancer cell lines promoted YAP1 expression and accessible to the nucleus. In addition, DCLK1 up-regulated the expression of YAP1 binding transcription factor TEAD and increased the mRNA expression levels of downstream malignant behavior-promoting molecules. Finally, Verteporfin, an inhibitor of the Hippo pathway, could antagonize the cell's malignant behavior-promoting ability mediated by high expression of DCLK1. We found that the number of migrated cells with DCLK1 overexpressing AsPC-1 group was 68.33±7.09, which was significantly higher than 22.00±4.58 of DCLK1 overexpressing cells treated with Verteporfin (P<0.05). Similarly, the migration number of PANC-1 cells overexpressing DCLK1 was 65.66±8.73, which was significantly higher than 37.00±6.00 of the control group and 32.33±9.61 of Hippo pathway inhibitor-treated group (P<0.05). Meanwhile, the number of invasive cells in the DCLK1-overexpressed group was significantly higher than that in the DCLK1 wild-type group cells, while the Verteporfin-treated DCLK1-overexpressed cells showed a significant decrease. In addition, we monitored the cell proliferation index using the real-time cellular analysis (RTCA) assay, and the proliferation index of DCLK1-overexpressed AsPC-1 cells was 0.66±0.04, which was significantly higher than 0.38±0.01 of DCLK1 wild-type AsPC-1 cells (P<0.05) as well as 0.05±0.03 of DCLK1-overexpressed AsPC1 cells treated with Verteporfin (P<0.05). PANC-1 cells showed the same pattern, with a proliferation index of 0.77±0.04 for DCLK1-overexpressed PANC-1 cells, significantly higher than DCLK1-overexpressed PANC1 cells after Verteporfin treatment (0.14±0.05, P<0.05). Conclusion: The expression of DCLK1 is remarkably associated with the Hippo pathway, it promotes the migration, invasion, and proliferation of pancreatic cancer cells by activating the Hippo pathway.
Humans ; Doublecortin-Like Kinases ; Hippo Signaling Pathway ; Verteporfin/pharmacology* ; Cell Line, Tumor ; Protein Serine-Threonine Kinases/metabolism* ; Pancreatic Neoplasms/pathology* ; YAP-Signaling Proteins ; Transcription Factors/metabolism* ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic ; Tumor Suppressor Proteins/genetics*

Objective To investigate the effects of YAP on the occurrence and progression of acute liver failure by regulating the ferroptosis pathway and its underlying mechanism. Methods A total of 20 8-week-old C57BL/6 mice were randomly divided into four groups: a control group, an acute liver failure model group, a YAP agonist XMU-MP-1 treatment group and a YAP inhibitor verteporfin treatment group, five mice for each group. HE staining was used to observe the pathological changes of hepatic inflammation and necrosis. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were detected by liver biochemistry. Iron (Fe), malondialdehyde (MDA), glutathione (GSH) determination kits were used to measure their levels in liver tissues of each group. The changes of hepatocyte mitochondrial in each group were observed by electron microscopy. Real time PCR and Western blot analysis were used to detect the mRNA and protein expressions of YAP, glutathione peroxidase 4 (GPX4) and 5-lipoxygenase (5-LOX). Results Compared with the control group, mice in the acute liver failure model group and the YAP inhibitor verteporfin treatment group showed severe liver tissue congestion with inflammatory cell infiltration and structural damage to hepatic lobules. Liver injury was alleviated in the XMU-MP-1 treatment group. With the occurrence of liver failure, plasma ALT and AST levels significantly increased, and liver function was improved in XMU-MP-1 treatment group. Electron microscopy showed that mitochondria in hepatocytes of mice with liver failure became smaller and bilayer membrane density increased, while mitochondria changes in the XMU-MP-1 group were alleviated. In addition, the acute liver failure model group showed an increase in Fe and MDA contents, decreased protein expressions of GPX4, and enhanced expression of 5-LOX, suggesting that ferroptosis was involved in acute liver failure in C57BL/6 mice. Ferroptosis was inhibited by activation of YAP. Conclusion Activation of YAP may ameliorate liver injury by inhibiting ferroptosis.
Animals ; Mice ; Ferroptosis ; Glutathione ; Liver Failure ; Liver Failure, Acute/drug therapy* ; Mice, Inbred C57BL ; Verteporfin ; YAP-Signaling Proteins/metabolism*