The Hippo kinase, NDR2, plays a key role in the natural history of several human cancers, particularly lung cancer, by regulating processes such as proliferation, apoptosis, migration, invasion, vesicular trafficking, autophagy, ciliogenesis and immune response. To examine the specificity of NDR2's action, interaction and function in physiological or tumoral contexts, we first focus on the structural differences in the amino-acid sequence between NDR1 and NDR2. We then establish a correlation between these NDR1/2 differences and specific post-translational regulation, as well as the distinct action, interactions, and functions of NDR2 in physiological or tumoral paradigms, such as lung cancer. Furthermore, the full set of NDR2 partners and/or substrates remains to be identified. Given that it is hypothesized that NDR2 and its partners may offer new perspectives for anticancer therapies, we emphasize potential clustering or functional enrichment networks among the NDR2-specific interactants. Additionally, we provide an unpublished proteomic comparison of the NDR1 versus NDR2 interactome, focusing on human bronchial epithelial cells (HBEC-3), lung adenocarcinoma cells (H2030), and their brain metastasis-derived counterparts (H2030-BrM3). In conclusion, this study underscores the pivotal role of NDR2 in cancer progression, particularly lung cancer, and helps to better understand their specific functions and interactions in both normal and tumor contexts. The identification of NDR2 partners and substrates remains essential, with the potential to open new avenues for anticancer therapies.

The Hippo signaling pathway is critical for regulating cell growth, tissue homeostasis, and organ size. Dysregulation of this pathway has been associated with a range of pathologies, especially cancer, through its modulation of downstream effectors-Yes-associated protein (YAP) and the transcriptional coactivator with PDZ-binding motif (TAZ). These proteins bind to transcriptional enhanced associate domain (TEAD) proteins and function as transcription factors in the nucleus, producing oncogenic target genes such as CTGF and CYR61. TEAD proteins require palmitoylation via a covalent bond with cysteine in the central pocket to bind YAP/TAZ. Therefore, competitive inhibition that prevents palmitoylation could serve as an effective anticancer strategy. In this study, we analyzed the crystal structures of the known inhibitor VT-105 bound to TEAD3 to identify new binding spots that were previously unexplored, with the aim of discovering more potent compounds using structure-based drug design. Consequently, we identified a novel hydrogen-bonding site and discovered C-2, which effectively binds to this site, as confirmed by X-ray crystallography. Furthermore, C-2 exhibited stable pharmacokinetic properties and demonstrated impressive efficacy in a mouse xenograft model.

The Hippo signalling pathway is prominent and governs cell proliferation and stem cell activity, acting as a growth regulator and tumour suppressor. Defects in Hippo signalling and hyperactivation of its downstream effector's Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) play roles in cancer development, implying that pharmacological inhibition of YAP and TAZ activity could be an effective cancer treatment strategy. Conversely, YAP and TAZ can also have beneficial effects in promoting tissue repair and regeneration following damage, therefore their activation may be therapeutically effective in certain instances. Recently, a complex network of intracellular and extracellular signalling mechanisms that affect YAP and TAZ activity has been uncovered. The YAP/TAZ-TEAD interaction leads to tumour development and the protein structure of YAP/TAZ-TEAD includes three interfaces and one hydrophobic pocket. There are clinical and preclinical trial drugs available to inhibit the hippo signalling pathway, but these drugs have moderate to severe side effects, so researchers are in search of novel, potent, and selective hippo signalling pathway inhibitors. In this review, we have discussed the hippo pathway in detail, including its structure, activation, and role in cancer. We have also provided the various inhibitors under clinical and preclinical trials, and advancement of small molecules their detailed docking analysis, structure-activity relationship, and biological activity. We anticipate that the current study will be a helpful resource for researchers.

The receptor tyrosine kinase (RTK)/Ras/Raf/MEK/ERK signaling pathway is one of the most tumorigenic pathways in cancer, with its hyperactivation strongly linked to the aggressive nature of glioblastoma (GBM). Although extensive research has focused on developing therapeutics targeting this pathway, clinical success remains elusive due to the emergence of resistance mechanisms.

This review investigates how inhibition of the RTK/Ras/Raf/MEK/ERK pathway alters transcription factors, contributing to acquired resistance mechanisms in GBM. It also highlights the critical role of transcription factor dysregulation in therapeutic resistance.

Findings from key studies on the RTK/Ras/Raf/MEK/ERK pathway in GBM were synthesized to explore the role of transcription factor dysregulation in resistance to targeted therapies, radiation, and chemotherapy. The review highlights that transcription factors undergo significant dysregulation following RTK/Ras/Raf/MEK/ERK pathway inhibition, contributing to therapeutic resistance.

Transcription factors are promising targets for overcoming treatment resistance in GBM, with cotreatment strategies combining RTK/Ras/Raf/MEK/ERK pathway inhibitors and transcription factor-targeted therapies presenting a novel approach. Despite the challenges of targeting complex structures and interactions, advancements in drug development and precision technologies hold great potential. Continued research is essential to refine these strategies and improve outcomes for GBM and other aggressive cancers.

Ewing sarcoma (EwS) is an aggressive cancer of adolescents in need of effective treatment. Insulin-like growth factor (IGF)-1 is an autocrine growth factor for EwS, but only 10% of patients respond to IGF-1 receptor (IGF-1R) blockade. Although EwS is presumed to originate from mesenchymal progenitors during bone development, targeting of the EwS driver oncogene EWS::FLI1 to the mesenchymal lineage in a mouse model does not result in tumor formation but in skeletal malformations and perinatal death. We report that transient exposure to IGF-1 concentrations mimicking serum levels during puberty reprograms limb-derived mesenchymal cells of EWS::FLI1-mutant mice to stable transformation and tumorigenicity. We identify a modular mechanism of IGF-1-driven tumor promotion in the early steps of EwS pathogenesis, in which Yap1 plays a central role. Pharmacologic Yap1/Tead inhibition reverses the transformed phenotype of EWS::FLI1-expressing cells. Our data provide a rationale for combined IGF-1R and YAP/TEAD inhibition in the treatment of EwS patients.

The Hippo signaling pathway is a pivotal regulator of tissue homeostasis, organ size, and cell proliferation. Its dysregulation is profoundly implicated in various forms of cancer, making it a highly promising target for therapeutic intervention. This review extensively evaluates the mechanisms underlying the dysregulation of the Hippo pathway in cancer cells and the molecular processes linking these alterations to tumorigenesis. Under normal physiological conditions, the Hippo pathway is a guardian, ensuring controlled cellular proliferation and programmed cell death. However, numerous mutations and epigenetic modifications can disrupt this equilibrium in cancer cells, leading to unchecked cell proliferation, enhanced survival, and metastatic capabilities. The pathway's interaction with other critical signaling networks, including Wnt/β-catenin, PI3K/Akt, TGF-β/SMAD, and EGFR pathways, further amplifies its oncogenic potential. Central to these disruptions is the activation of YAP and TAZ transcriptional coactivators, which drive the expression of genes that promote oncogenesis. This review delves into the molecular mechanisms responsible for the dysregulation of the Hippo pathway in cancer, elucidating how these disruptions contribute to tumorigenesis. We also explore potential therapeutic strategies, including inhibitors targeting YAP/TAZ activity and modulators of upstream signaling components. Despite significant advancements in understanding the Hippo pathway's role in cancer, numerous questions remain unresolved. Continued research is imperative to unravel the complex interactions within this pathway and to develop innovative and effective therapies for clinical application. In conclusion, the comprehensive understanding of the Hippo pathway's regulatory mechanisms offers significant potential for advancing cancer therapies, regenerative medicine, and treatments for chronic diseases. The translation of these insights into clinical practice will necessitate collaborative efforts from researchers, clinicians, and pharmaceutical developers to bring novel and effective therapies to patients, ultimately improving clinical outcomes and advancing the field of oncology.

The Hippo signaling pathway is an evolutionarily conserved, tumor suppressor, stem cell pathway. This is the very less explored pathway in Breast Cancer. It is a crucial regulator of several biological processes, such as organ size, differentiation, tissue homeostasis, cellular proliferation, and stemness. Interestingly, deregulation of this pathway leads to tumorigenesis. Hence, the present study aims to identify the role of the Hippo signaling pathway in Breast Cancer.

The mRNA expression of the Hippo signaling pathway molecules was evaluated in 120 pre-therapeutic patients by quantitative real-time PCR. Statistical analysis was carried out using SPSS 23. The association between the gene expression and clinicopathological parameters was analyzed by the paired sample t-test, and Pearson chi-square test. ROC curve analysis was carried out using Med Cal. A p-value of ≤ 0.05 was considered statistically significant.

The hippo signaling pathway contains 10 core components i.e.SAV1, MOB1A, MOB1B, MST1, MST2, LATS1, LATS2, YAP, TAZ, and TEAD1 which were downregulated in malignant tissues as compared to adjacent normal tissue in breast cancer. In the correlation of hippo signaling pathway molecules with clinico pathological parameters, only LATS1, MST1, and SAV1 were found to be significantly negatively associated with stages of Breast Cancer. MOB1B was found to be significantly positively correlated with stages of Breast Cancer. ROC curve analysis of YAP, TAZ, LATS2, and TEAD showed significant discrimination between adjacent normal and malignant tissue.

In the current study, all the molecules of the hippo signaling pathway i.e. YAP, TAZ, LATS1, LATS2, MST1, MST2, SAV1, MOB1, MOB1B, TEAD1 were downregulated in BC suggesting the activation of hippo pathway which played a significant role in tumor suppression.

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers, with high rates of metastasis and lethality. EF-hand domain-containing protein D1 (EFHD1) and salt-inducible kinase 3 (SIK3) have been studied in several cancer types. Aberrant expression of EFHD1 and SIK3 has been observed in CRC, but little research has addressed their regulatory abilities and signaling pathways. In this study, we aimed to explore the efficacy of EFHD1 in inhibiting CRC proliferation and metastasis and to elucidate the underlying mechanisms involved in the upregulation of SIK3 expression. Cell viability, colony formation, wound healing, Transwell assay, orthotopic xenograft, and pulmonary metastasis mouse models were used to detect the antiproliferative and anti-metastatic effects of EFHD1 against CRC in vitro and in vivo. The Gene Expression Profiling Interactive Analysis (GEPIA) database was used to determine EFHD1 and SIK3 expression in CRC. The regulatory roles of EFHD1 and SIK3 in mediating anti-metastatic effects in CRC were measured using western blotting, immunohistochemical, and immunofluorescence analyses. The results showed that EFHD1 expression was significantly repressed in the clinical CRC samples. EFHD1 markedly suppressed cell proliferation, migration, and invasion in vitro and inhibited tumor growth and metastasis in vivo. Analysis of the GEPIA database revealed that EFHD1 expression positively correlated with SIK3 expression. SIK3 overexpression inhibited the migration of CRC cells, and SIK3 knockdown partially eliminated the inhibitory effects of EFHD1 on CRC metastasis. EFHD1 exerted anti-metastatic effects against CRC via upregulating SIK3 and inhibiting epithelial-mesenchymal transition (EMT) processing through modulating the Hippo signaling pathway. Collectively, these findings identify EFHD1 as a potent SIK3 agonist and highlight the EFHD1-SIK3 axis as a key modulator of the Hippo signaling pathway in CRC. EFHD1 serves as a novel regulator and is worthy of further development as a novel therapeutic target in CRC.

Over the last decade, Hippo signaling has emerged as a major tumor-suppressing pathway. Its dysregulation is associated with abnormal expression of YAP1 and TEAD-family genes. Recent works have highlighted the role of YAP1/TEAD activity in several cancers and its potential therapeutic implications. Therefore, identifying patients with a dysregulated Hippo pathway is key to enhancing treatment impact. Although recent studies have derived RNA-seq-based signatures, there remains a need for a reproducible and cost-effective method to measure the pathway activation. In recent years, deep learning applied to histology slides have emerged as an effective way to predict molecular information from a data modality available in clinical routine. Here, we trained models to predict YAP1/TEAD activity from H&E-stained histology slides in multiple cancers. The robustness of our approach was assessed in seven independent validation cohorts. Finally, we showed that histological markers of disease aggressiveness were associated with dysfunctional Hippo signaling.

Glioblastoma multiforme (GBM) is one of the most aggressive and treatment-resistant forms of brain cancer. Current therapeutic strategies, including surgery, chemotherapy, and radiotherapy, often fail due to the tumor's ability to develop resistance. The proteins YAP-1 (Yes-associated protein 1) and PARP-1 (Poly-(ADP-ribose)-polymerase-1) have been implicated in this resistance, playing crucial roles in cell proliferation and DNA repair mechanisms, respectively. This study explored the inhibitory potential of natural compounds from Lepidium meyenii (Peruvian Maca) on the YAP-1 and PARP-1 protein systems to develop novel therapeutic strategies for GBM. By molecular dynamics simulations, we identified N-(3-Methoxybenzyl)-(9Z,12Z,15Z)- octadecatrienamide (DK5) as the most promising natural inhibitor for PARP-1 and stearic acid (GK4) for YAP-1. Although synthetic inhibitors, such as Olaparib (ODK) for PARP-1 and Verteporfin (VER) for YAP-1, only VER was superior to the naturally occurring molecule and proved a promising alternative. In conclusion, natural compounds from Lepidium meyenii (Peruvian Maca) offer a potentially innovative approach to improve GBM treatment, complementing existing therapies with their inhibitory action on PARP-1 and YAP-1.

Fenamates as classical nonsteroidal anti-inflammatory agents are widely used for relieving pain. Preclinical studies and epidemiological data highlight their chemo-preventive and chemotherapeutic potential for cancer. However, comprehensive reviews of fenamates in cancer are limited. To accelerate the repurposing of fenamates, this review summarizes the results of fenamates alone or in combination with existing chemotherapeutic agents. This paper also explores targets of fenamates in cancer therapy, including COX, AKR family, AR, gap junction, FTO, TEAD, DHODH, TAS2R14, ion channels, and DNA. Besides, this paper discusses other mechanisms, such as regulating Wnt/β-catenin, TGF-β, p38 MAPK, and NF-κB pathway, and the regulation of the expressions of Sp, EGR-1, NAG-1, ATF-3, ErbB2, AR, as well as the modulation of the tumor immune microenvironment. Furthermore, this paper outlined the structural modifications of fenamates, highlighting their potential as promising leads for anticancer drugs.

The Hippo pathway, a kinase cascade, coordinates with many intracellular signals and mediates the regulation of the activities of various downstream transcription factors and their coactivators to maintain homeostasis. Therefore, the aberrant activation of the Hippo pathway and its associated molecules imposes significant stress on tissues and cells, leading to cancer, immune disorders, and a number of diseases. Cellular senescence, the mechanism by which cells counteract stress, prevents cells from unnecessary damage and leads to sustained cell cycle arrest. It acts as a powerful defense mechanism against normal organ development and aging-related diseases. On the other hand, the accumulation of senescent cells without their proper removal contributes to the development or worsening of cancer and age-related diseases. A correlation was recently reported between the Hippo pathway and cellular senescence, which preserves tissue homeostasis. This review is the first to describe the close relationship between aging and the Hippo pathway, and provides insights into the mechanisms of aging and the development of age-related diseases. In addition, it describes advanced findings that may lead to the development of tissue regeneration therapies and drugs targeting rejuvenation.

The Hippo pathway plays a tumorigenic role in highly angiogenic glioblastoma (GBM), whereas little is known about clinically relevant Hippo pathway inhibitors' ability to target adaptive mechanisms involved in GBM chemoresistance. Their molecular impact was investigated here in vitro against an alternative process to tumour angiogenesis termed vasculogenic mimicry (VM) in GBM-derived cell models. In silico analysis of the downstream Hippo signalling members YAP1, TAZ and TEAD1 transcript levels in low-grade glioblastoma (LGG) and GBM tumour tissues was performed using GEPIA. TAZ transcript levels did not differ between the healthy and tumour tissues data analysed. In contrast, YAP1 transcript levels were elevated in GBM tissues, whereas TEAD1 levels were high in both LGG and GBM. All three Hippo pathway inhibitors tested, GNE7883, VT107 and IAG933 effectively inhibited U87 and U251 cell migration and in vitro VM as assessed on Cultrex matrix. YAP1 gene and protein expression were induced upon VM, and its translocation to the nucleus was inhibited by the Hippo pathway inhibitors tested. SiRNA-mediated transient silencing of YAP1 repressed cell migration, VM formation and CTGF and Cyr61 transcription. In conclusion, targeting of VM using Hippo pathway inhibitors could help circumvent GBM chemoresistance and effectively complement other brain cancer treatments.

The Hippo signaling governs the expression of genes critically important for cell proliferation and survival. The components of this pathway are considered antitumor drug targets. However, the design of Hippo inhibitors is a challenge given the complexity of the network and redundancy of its elements.

We review the current state-of-the-art in the structure of the Hippo pathway, the microenvironment-induced extracellular cues, the strategies to design pharmacological instruments for inactivation of the Hippo signaling using small molecular weight modulators, as well as the results of initial clinical trials.

One special characteristic of the Hippo signaling is the adverse role of phosphorylation: opposite to classical kinase cascades that activate the transcription factors, the Hippo kinases retain their partners in a transcriptionally inactive state. Therefore, approaches for pharmacological or genetic inhibition of Hippo protein kinases are counterproductive. The developing alternatives such as disruption of protein-protein interactions or PROTAC techniques are straightforward for preventing the Hippo signaling in cancer therapy.

Colorectal cancer (CRC) stands as a significant global health issue, marked by elevated occurrence and mortality statistics. Despite the availability of various treatments, including chemotherapy, radiotherapy, and targeted therapy, CRC cells often exhibit resistance to these interventions. As a result, it is imperative to identify the disease at an earlier stage and enhance the response to treatment by acquiring a deeper comprehension of the processes driving tumor formation, aggressiveness, metastasis, and resistance to therapy. The Hippo pathway plays a critical role in facilitating the initiation of tumorigenesis and frequently experiences disruption within CRC because of genetic mutations and modified expression in its fundamental constituents. Targeting upstream regulators or core Hippo pathway components may provide innovative therapeutic strategies for modulating Hippo signaling dysfunction in CRC. To advance novel therapeutic techniques for CRC, it is imperative to grasp the involvement of the Hippo pathway in CRC and its interaction with alternate signaling pathways, noncoding RNAs, gut microbiota, and the immune microenvironment. This review seeks to illuminate the function and control of the Hippo pathway in CRC, ultimately aiming to unearth innovative therapeutic methodologies for addressing this ailment.

The transcription factors, TEAD1-4 together with their co-activator YAP/TAZ function as key downstream effectors of the Hippo pathway. Hyperactivation of TEAD-YAP/TAZ activity is observed in many human cancers. TEAD1-4 possess distinct physiological and pathological functions, with conserved sequences and structures. Targeting specific isoforms within TEAD1-4 can serve as valuable chemical probes for investigating TEAD-related functions in both development and diseases. We report the TEAD-targeting proteolysis targeting chimera (PROTAC), HC278, which achieves effective and specific targeting of TEAD1 and TEAD3 at low nanomolar doses while weakly degrading TEAD2 and TEAD4 at higher doses. Proteomic analysis of >6000 proteins confirmed their highly selective TEAD1 and TEAD3 degradation. Consistently, HC278 can suppress the proliferation of YAP-dependent NCI-H226 mesothelioma cells. Mechanistic exploration revealed that both CRBN and proteasome systems are involved in the TEAD degradation induced by HC278. Moreover, RNA-seq and Gene Set Enrichment Analysis (GSEA) revealed that the YAP signature genes such as CTGF, CYR61, and ANKRD1 are significantly downregulated by HC278 treatment. Overall, HC278 serves as a valuable chemical tool for unraveling the intricate biological roles of TEAD1 and TEAD3 and holds the potential as a lead compound for developing targeted therapy for TEAD1/3-driven pathologies.

Many tumor types harbor alterations in the Hippo pathway, including mesothelioma, where a high percentage of cases are considered YAP1/TEAD dependent. Identification of autopalmitoylation sites in the hydrophobic palmitate pocket of TEADs, which may be necessary for YAP1 protein interactions, has enabled modern drug discovery platforms to generate compounds that allosterically inhibit YAP1/TEAD complex formation and transcriptional activity. We report the discovery and characterization of a novel YAP1/TEAD inhibitor MRK-A from an aryl ether chemical series demonstrating potent and specific inhibition of YAP1/TEAD activity. In vivo, MRK-A showed a favorable tolerability profile in mice and demonstrated pharmacokinetics suitable for twice daily oral dosing in preclinical efficacy studies. Importantly, monotherapeutic targeting of YAP1/TEAD in preclinical models generated regressions in a mesothelioma CDX model; however, rapid resistance to therapy was observed. RNA-sequencing of resistant tumors revealed mRNA expression changes correlated with the resistance state and a marked increase of hepatocyte growth factor (HGF) expression. In vitro, exogenous HGF was able to fully rescue cytostasis induced by MRK-A in mesothelioma cell lines. In addition, co-administration of small molecule inhibitors of the MET receptor tyrosine kinase suppressed the resistance generating effect of HGF on MRK-A induced growth inhibition. In this work, we report the structure and characterization of MRK-A, demonstrating potent and specific inhibition of YAP1/TAZ-TEAD-mediated transcriptional responses, with potential implications for treating malignancies driven by altered Hippo signaling, including factors resulting in acquired drug resistance.

Neurofibromatosis Type II (NFII) is a genetic condition caused by loss of the NF2 gene, resulting in activation of the YAP/TAZ pathway and recurrent Schwann cell tumors, as well as meningiomas and ependymomas. Unfortunately, few pharmacological options are available for NFII. Here, we undertake a genome-wide CRISPR/Cas9 screen to search for synthetic-lethal genes that, when inhibited, cause death of NF2 mutant Schwann cells but not NF2 wildtype cells. We identify ACSL3 and G6PD as two synthetic-lethal partners for NF2, both involved in lipid biogenesis and cellular redox. We find that NF2 mutant Schwann cells are more oxidized than control cells, in part due to reduced expression of genes involved in NADPH generation such as ME1. Since G6PD and ME1 redundantly generate cytosolic NADPH, lack of either one is compatible with cell viability, but not down-regulation of both. Since genetic deficiency for G6PD is tolerated in the human population, G6PD could be a good pharmacological target for NFII.

Lung cancer is the primary contributor to cancer-related deaths globally, and non-small cell lung cancer (NSCLC) constitutes around 85% of all lung cancer cases. Recently, the emergence of targeted therapy and immunotherapy revolutionized the treatment of NSCLC and greatly improved patients' survival. However, drug resistance is inevitable, and extensive research has demonstrated that the Hippo pathway plays a crucial role in the development of drug resistance in NSCLC. The Hippo pathway is a highly conserved signaling pathway that is essential for various biological processes, including organ development, maintenance of epithelial balance, tissue regeneration, wound healing, and immune regulation. This pathway exerts its effects through two key transcription factors, namely Yes-associated protein (YAP) and transcriptional co-activator PDZ-binding motif (TAZ). They regulate gene expression by interacting with the transcriptional-enhanced associate domain (TEAD) family. In recent years, this pathway has been extensively studied in NSCLC. The review summarizes a comprehensive overview of the involvement of this pathway in NSCLC, and discusses the mechanisms of drug resistance, potential targets, and biomarkers associated with this pathway in NSCLC.

Targeted therapies are effective cancer treatments when accompanied by accurate diagnostic tests that can help identify patients that will respond to those therapies. The YAP/TAZ-TEAD axis is activated and plays a causal role in several cancer types, and TEAD inhibitors are currently in early-phase clinical trials in cancer patients. However, a lack of a reliable way to identify tumors with YAP/TAZ-TEAD activation for most cancer types makes it difficult to determine which tumors will be susceptible to TEAD inhibitors. Here, we used a combination of RNA-seq and bioinformatic analysis of metastatic melanoma cells to develop a YAP/TAZ gene signature. We found that the genes in this signature are TEAD-dependent in several melanoma cell lines, and that their expression strongly correlates with YAP/TAZ activation in human melanomas. Using DepMap dependency data, we found that this YAP/TAZ signature was predictive of melanoma cell dependence upon YAP/TAZ or TEADs. Importantly, this was not limited to melanoma because this signature was also predictive when tested on a panel of over 1000 cancer cell lines representing numerous distinct cancer types. Our results suggest that YAP/TAZ gene signatures like ours may be effective tools to predict tumor cell dependence upon YAP/TAZ-TEAD, and thus potentially provide a means to identify patients likely to benefit from TEAD inhibitors.

Irisin is a hormone-like factor secreted by muscle cells and produced by cleavage of the membrane protein fibronectin type III domain protein 5 (FNDC5), which exerts anti-inflammatory and anti-proliferative effects. However, the effects and the underlying mechanisms of irisin in rheumatoid arthritis (RA) are still unclear.

Collagen-induced arthritis (CIA) model was induced in DBA/1 mice and then treated with irisin. Arthritis index, paw thickness, weight, number of affected paws, serum inflammatory factors and related pathological tests were measured. RA fibroblast-like synoviocytes (RA-FLSs) were pretreated with IL-1β and irisin, and the migration, proliferation, invasion, oxidative stress and mitochondrial related function of RA-FLSs were detected.

Irisin significantly improved arthritis symptoms in CIA mice, as indicated by reduced arthritis index, alleviated paw thickness, decreased the number of affected paws and inhibited release of inflammatory factors. Irisin alleviated joint destruction, FLSs proliferation and the expression of YES-associated protein (YAP) and mitochondrial dynamic related protein 1 (Drp1) in the FLSs of CIA mice. In vitro experiment, irisin inhibited the proliferation, migration and invasion of RA-FLSs and improved oxidative stress induced by IL-1β, thereby restraining the pathogenic transformation of RA-FLSs. Mechanically, irisin suppressed the nuclear translocation of YAP, in turn, could reduce the synthesis of Drp1 protein and inhibit the mitochondrial fission of RA-FLSs, which was reversed by YAP agonists. Therefore, irisin has a protective effect on RA.

Irisin inhibits the proliferation, migration, invasion and inflammatory response of RA-FLSs by inhibiting the YAP-Drp1 signaling pathway, which implies a potential therapeutic effect on RA.

The immune system is an important defense against diseases, and it is essential to maintain the homeostasis of the body's internal environment. Under normal physiological conditions, the steady state of the immune system should be sustained to play normal immune response and immune function. Exploring the molecular mechanism of maintaining immune homeostasis under physiological and pathological conditions will provides understanding of the pathogenesis of autoimmune diseases, infections, metabolic disorders, and tumors, as well as new ideas and molecular targets for the prevention and treatment of these diseases. Hippo signaling pathway can not only regulate immune cells such as macrophages, T cells and dendritic cells, but also interact with immune-related signaling pathways such as NF-kB signaling pathway, TGF-β signaling pathway and Toll-like receptor signaling pathway, so as to resist the internal environment disorder caused by the invasion of exogenous pathogenic microorganisms and maintain the internal environment stability and physiological balance of the body. Hippo signaling pathway is also involved in the pathological process of immune system-related diseases such as rheumatoid arthritis, inflammatory bowel disease and psoriasis. Hippo pathway is closely related to organ development, stem cell biology, regeneration, and tumor biology. It affects cell differentiation by participating in extracellular and intracellular physiological signal reactions, sensing cell environment, and coordinating cell reactions. This pathway is crucial in maintaining immune homeostasis. This review summarizes the mechanism of Hippo pathway in different immune cells and some autoimmune diseases and the interaction between different immune signaling pathways and Hippo signaling pathway. It aims to explore the role of Hippo in autoimmune diseases and provide theoretical and practical basis for the treatment of autoimmune diseases through Hippo signaling pathway.

The transcription factor YAP-TEAD is the downstream effector of the Hippo pathway which controls cell proliferation, apoptosis, tissue repair, and organ growth. Dysregulation of the Hippo pathway has been correlated with carcinogenic processes. A co-crystal structure of TEAD with its endogenous ligand palmitic acid (PA) as well as with flufenamic acid (FA) has been disclosed. Here we report the development of HC-258, which derives from FA and possesses an oxopentyl chain that mimics a molecule of PA as well as an acrylamide that reacts covalently with TEAD's cysteine. HC-258 reduces the CTGF, CYR61, AXL, and NF2 transcript levels and inhibits the migration of MDA-MB-231 breast cancer cells. Co-crystallization with hTEAD2 confirmed that HC-258 binds within TEAD's PA pocket, where it forms a covalent bond with its cysteine.

Cancer cells exhibit aberrant extracellular matrix mechanosensing due to the altered expression of mechanosensory cytoskeletal proteins. Such aberrant mechanosensing of the tumor microenvironment (TME) by cancer cells is associated with disease development and progression. In addition, recent studies show that such mechanosensing changes the mechanobiological properties of cells, and in turn cells become susceptible to mechanical perturbations. Due to an increasing understanding of cell biomechanics and cellular machinery, several approaches have emerged to target the mechanobiological properties of cancer cells and cancer-associated cells to inhibit cancer growth and progression. In this Perspective, we summarize the progress in developing mechano-based approaches to target cancer by interfering with the cellular mechanosensing machinery and overall TME.

The Hippo pathway regulates organ size and tissue homeostasis by controlling cell proliferation and apoptosis. The YAP-TEAD transcription factor, the downstream effector of the Hippo pathway, regulates the expression of genes such as CTGF, Cyr61, Axl and NF2. Aberrant Hippo activity has been identified in multiple types of cancers. Flufenamic acid (FA) was reported to bind in a liphophilic TEAD palmitic acid (PA) pocket, leading to reduction of the expression of Axl and NF2. Here, we show that the replacement of the trifluoromethyl moiety in FA by aromatic groups, directly connected to the scaffold or separated by a linker, leads to compounds with better affinity to TEAD. Co-crystallization studies show that these compounds bind similarly to FA, but deeper within the PA pocket. Our studies identified LM-41 and AF-2112 as two TEAD binders that strongly reduce the expression of CTGF, Cyr61, Axl and NF2. LM-41 gave the strongest reduction of migration of human MDA-MB-231 breast cancer cells.

Yes-associated Protein (YAP) and its paralog Transcriptional Coactivator with PDZ-binding Motif (TAZ) are major regulators of gene transcription/expression, primarily controlled by the Hippo pathway and the cytoskeleton. Integrating an array of chemical and mechanical signals, they impact growth, differentiation, and regeneration. Accordingly, they also play key roles in tumorigenesis and metastasis formation. Their activity is primarily regulated by their localization, that is, Hippo pathway- and/or cytoskeleton-controlled cytosolic or nuclear sequestration. While many details of such prevailing retention models have been elucidated, much less is known about their actual nuclear traffic: import and export. Although their size is not far from the cutoff for passive diffusion through the nuclear pore complex (NPC), and they do not contain any classic nuclear localization (NLS) or nuclear export signal (NES), evidence has been accumulating that their shuttling involves mediated and thus regulatable/targetable processes. The aim of this review is to summarize emerging information/concepts about their nucleocytoplasmic shuttling, encompassing the relevant structural requirements (NLS, NES), nuclear transport receptors (NTRs, karyophererins), and NPC components, along with the potential transport mechanisms and their regulation. While dissecting retention vs. transport is often challenging, the emerging picture suggests that YAP/TAZ shuttles across the NPC via multiple, non-exclusive, mediated mechanisms, constituting a novel and intriguing facet of YAP/TAZ biology.

The MAPK pathway is important in human lung cancer and is improperly activated in a substantial proportion through number of ways. Strategies on dual-targeting RAF and MEK are an alternative option to diminish the limitations in this pathway inhibition. Hence, we implemented parallel pharmacophore screening of 11,808 DrugBank compounds against RAF and MEK. ADHRR and DHHRR were modeled as a pharmacophore hypothesis for RAF and MEK respectively. Importantly, these hypotheses resulted an AUC value of > 0.90 with the external data set. As a result of phase screening, glide docking, and prime-MM/GBSA scoring, it is determined that DB08424 and DB08907 have the best chances of acting as multi-kinase inhibitors. The pi-cation interaction with key amino acid residues of both target receptors may responsible for the stronger binding with these kinases. Cumulative 600 ns MD simulation studies validate the binding ability of these compounds. Significantly, the hit compounds resulted higher number of stable conformational state with less atomic movements than the reference compound against both targets. The anti-cancer efficacy of the lead compounds was validated through machine learning-based approaches. These findings suggest that DB08424 and DB08907 might be novel molecules to be explored further experimentally to block the MAPK signaling in lung cancer patients.

Induction of cytochrome P450 (CYP) genes constitutes an important cause of drug-drug interactions and preclinical evaluation of induction liability is mandatory for novel drug candidates. YAP/TEAD signaling has emerged as an attractive target for various oncological indications and multiple chemically distinct YAP/TEAD inhibitors are rapidly progressing towards clinical stages. Here, we tested the liability for CYP induction of a diverse set of YAP/TEAD inhibitors with different modes of action and TEAD isoform selectivity profiles in monolayers and 3D spheroids of primary human hepatocytes (PHH). We found that YAP/TEAD inhibition resulted in broad induction of CYPs in 2D monolayers, whereas, if at all, only marginal induction was seen in spheroid culture. Comprehensive RNA-Seq indicated that YAP/TEAD signaling was increased in 2D culture compared to spheroids, which was paralleled by elevated activities of the interacting transcription factors LXR and ESRRA, likely at least in part due to altered mechanosensing. Inhibition of this YAP/TEAD hyperactivation resulted in an overall reduction of hepatocyte dedifferentiation marked by increased hepatic functionality, including CYPs. These results thus demonstrate that the observed induction is due to on-target effects of the compounds rather than direct activation of xenobiotic sensing nuclear receptors. Combined, the presented data link hepatocyte dedifferentiation to YAP/TEAD dysregulation, reveal a novel non-canonical pathway of CYP induction and highlight the advantage of organotypic 3D cultures to predict clinically relevant pharmacokinetic properties, particularly for atypical induction mechanisms.

YAP is a key transcriptional co-activator of TEADs, it regulates cell growth and is frequently activated in cancer. In Malignant Pleural Mesothelioma (MPM), YAP is activated by loss-of-function mutations in upstream components of the Hippo pathway, while, in Uveal Melanoma (UM), YAP is activated in a Hippo-independent manner. To date, it is unclear if and how the different oncogenic lesions activating YAP impact its oncogenic program, which is particularly relevant for designing selective anti-cancer therapies. Here we show that, despite YAP being essential in both MPM and UM, its interaction with TEAD is unexpectedly dispensable in UM, limiting the applicability of TEAD inhibitors in this cancer type. Systematic functional interrogation of YAP regulatory elements in both cancer types reveals convergent regulation of broad oncogenic drivers in both MPM and UM, but also strikingly selective programs. Our work reveals unanticipated lineage-specific features of the YAP regulatory network that provide important insights to guide the design of tailored therapeutic strategies to inhibit YAP signaling across different cancer types.

Glioblastoma is a highly aggressive brain tumor with a poor prognosis. Recent studies have suggested that mechanobiology, the study of how physical forces influence cellular behavior, plays an important role in glioblastoma progression. Several signaling pathways, molecules, and effectors, such as focal adhesions, stretch-activated ion channels, or membrane tension variations, have been studied in this regard. Also investigated are YAP/TAZ, downstream effectors of the Hippo pathway, which is a key regulator of cell proliferation and differentiation. In glioblastoma, YAP/TAZ have been shown to promote tumor growth and invasion by regulating genes involved in cell adhesion, migration, and extracellular matrix remodeling. YAP/TAZ can be activated by mechanical cues such as cell stiffness, matrix rigidity, and cell shape changes, which are all altered in the tumor microenvironment. Furthermore, YAP/TAZ have been shown to crosstalk with other signaling pathways, such as AKT, mTOR, and WNT, which are dysregulated in glioblastoma. Thus, understanding the role of mechanobiology and YAP/TAZ in glioblastoma progression could provide new insights into the development of novel therapeutic strategies. Targeting YAP/TAZ and mechanotransduction pathways in glioblastoma may offer a promising approach to treating this deadly disease.

Literature data on glioblastoma ongoingly underline the link between metabolism and cancer stemness, the latter is one responsible for potentiating the resistance to treatment, inter alia due to increased invasiveness. In recent years, glioblastoma stemness research has bashfully introduced a key aspect of cytoskeletal rearrangements, whereas the impact of the cytoskeleton on invasiveness is well known. Although non-stem glioblastoma cells are less invasive than glioblastoma stem cells (GSCs), these cells also acquire stemness with greater ease if characterized as invasive cells and not tumor core cells. This suggests that glioblastoma stemness should be further investigated for any phenomena related to the cytoskeleton and metabolism, as they may provide new invasion-related insights. Previously, we proved that interplay between metabolism and cytoskeleton existed in glioblastoma. Despite searching for cytoskeleton-related processes in which the investigated genes might have been involved, not only did we stumble across the relation to metabolism but also reported genes that were found to be implicated in stemness. Thus, dedicated research on these genes in GSCs seems justifiable and might reveal novel directions and/or biomarkers that could be utilized in the future. Herein, we review the previously identified cytoskeleton/metabolism-related genes through the prism of glioblastoma stemness.

The Hippo pathway is an evolutionary conserved signaling network involved in several cellular regulatory processes. Dephosphorylation and overexpression of Yes-associated proteins (YAPs) in the Hippo-off state are common in several types of solid tumors. YAP overexpression results in its nuclear translocation and interaction with transcriptional enhanced associate domain 1-4 (TEAD1-4) transcription factors. Covalent and non-covalent inhibitors have been developed to target several interaction sites between TEAD and YAP. The most targeted and effective site for these developed inhibitors is the palmitate-binding pocket in the TEAD1-4 proteins. Screening of a DNA-encoded library against the TEAD central pocket was performed experimentally to identify six new allosteric inhibitors. Inspired by the structure of the TED-347 inhibitor, chemical modification was performed on the original inhibitors by replacing secondary methyl amide with a chloromethyl ketone moiety. Various computational tools, including molecular dynamics, free energy perturbation, and Markov state model analysis, were employed to study the effect of ligand binding on the protein conformational space. Four of the six modified ligands were associated with enhanced allosteric communication between the TEAD4 and YAP1 domains indicated by the relative free energy perturbation to original molecules. Phe229, Thr332, Ile374, and Ile395 residues were revealed to be essential for the effective binding of the inhibitors.

Breast cancer (BCa) is the most prevalent type of cancer in women. Several therapies used in the treatment of breast cancer are associated with clinically important rates of cardiovascular toxicity during or after treatment exposure, including anthracyclines. There is a need for new BCa therapeutics and treatments that mitigate chemotherapy-induced cardiotoxicity in BCa. In this study, we examine the effects of Serine/Threonine Kinase 3 (STK3) inhibition in the context of BCa therapy and cardioprotection from doxorubicin. STK3 (also known as MST2) is a key member of the Hippo Tumor-Suppressor Pathway, which regulates cell growth and proliferation by inhibiting YAP/TAZ co-transcription factors. Canonically, STK3 should restrict BCa growth; however, we observed that STK3 is amplified in BCa and associated with worse patient outcomes, suggesting a noncanonical pro-tumorigenic role. We found BCa cell lines have varying dependence on STK3. SUM52PE cells had the highest expression and dependence on STK3 in genetic and pharmacological assays. MCF-7 and MDA-MB-231 were less sensitive to STK3 targeting in standard proliferation assays, but were STK3 dependent in colony formation and matrigel invasion assays. In contrast, STK3 inhibition mitigated the toxic effects of doxorubicin in H9C2 rat cardiomyocytes by increasing YAP expression. Importantly, STK3 inhibition in BCa cells did not interfere with the therapeutic effects of doxorubicin. Our studies highlight STK3 is a potential molecular target for BCa with dual therapeutic effects: suppression of BCa growth and progression, and chemoprotection in cardiomyocytes.

The Hippo signaling pathway is a highly conserved pathway that plays important roles in the regulation of cell proliferation and apoptosis. Transcription factors TEAD1-4 and transcriptional coregulators YAP/TAZ are the downstream effectors of the Hippo pathway and can modulate Hippo biology. Dysregulation of this pathway is implicated in tumorigenesis and acquired resistance to therapies. The emerging importance of YAP/TAZ-TEAD interaction in cancer development makes it a potential therapeutic target. In the past decade, disrupting YAP/TAZ-TEAD interaction as an effective approach for cancer treatment has achieved great progress. This approach followed a trajectory wherein peptidomimetic YAP-TEAD protein-protein interaction disruptors (PPIDs) were first designed, followed by the discovery of allosteric small molecule PPIDs, and currently, the development of direct small molecule PPIDs. YAP and TEAD form three interaction interfaces. Interfaces 2 and 3 are amenable for direct PPID design. One direct YAP-TEAD PPID (IAG933) that targets interface 3 has entered a clinical trial in 2021. However, in general, strategically designing effective small molecules PPIDs targeting TEAD interfaces 2 and 3 has been challenging compared with allosteric inhibitor development. This review focuses on the development of direct surface disruptors and discusses the challenges and opportunities for developing potent YAP/TAZ-TEAD inhibitors for the treatment of cancer.

Gastric cancer (GC) is an aggressive malignant disease which still lacks effective early diagnosis markers and targeted therapies, representing the fourth-leading cause of cancer-associated death worldwide. The Hippo signaling pathway plays crucial roles in organ size control and tissue homeostasis under physiological conditions, yet its aberrations have been closely associated with several hallmarks of cancer. The last decade witnessed a burst of investigations dissecting how Hippo dysregulation contributes to tumorigenesis, highlighting the therapeutic potential of targeting this pathway for tumor intervention. In this review, we systemically document studies on the Hippo pathway in the contexts of gastric tumor initiation, progression, metastasis, acquired drug resistance, and the emerging development of Hippo-targeting strategies. By summarizing major open questions in this field, we aim to inspire further in-depth understanding of Hippo signaling in GC development, as well as the translational implications of targeting Hippo for GC treatment.

The Hippo signaling pathway inhibits the activity of the oncogenic YAP (Yes-associated protein)/TAZ (transcriptional co-activator with PDZ-binding motif)-TEAD (TEA/ATTS domain) transcriptional complex. In cancers, inactivating mutations in upstream Hippo components and/or enhanced activity of YAP/TAZ and TEAD have been observed. The activity of this transcriptional complex can be effectively inhibited by targeting the TEAD family of transcription factors. The development of TEAD inhibitors has been driven by the discovery that TEAD has druggable hydrophobic pockets, and is currently at the clinical development stage. Three small molecule TEAD inhibitors are currently being tested in Phase I clinical trials. In this review, we highlight the role of TEADs in cancer, discuss various avenues through which TEAD activity can be inhibited, and outline the opportunities for the administration of TEAD inhibitors.

Our understanding of the function of the transcriptional regulators YAP and TAZ (YAP/TAZ) in cancer is advancing. In this Review, we provide an update on recent progress in YAP/TAZ biology, their regulation by Hippo signaling and mechanotransduction and highlight open questions. YAP/TAZ signaling is an addiction shared by multiple tumor types and their microenvironments, providing many malignant attributes. As such, it represents an important vulnerability that may offer a broad window of therapeutic efficacy, and here we give an overview of the current treatment strategies and pioneering clinical trials.