YAP/TAZ at the Roots of Cancer

SQLE amplification accelerates esophageal squamous cell carcinoma tumorigenesis and metastasis through oncometabolite 2,3-oxidosqualene repressing Hippo pathway

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent cancers worldwide, characterized by a dismal prognosis and elusive therapeutic targets. Dysregulated cholesterol metabolism is a critical hallmark of cancer cells, facilitating tumor progression. Here, we used whole genome sequencing data from several ESCC cohorts to identify the important role of squalene epoxidase (SQLE) in promoting ESCC tumorigenesis and metastasis. Specifically, our findings highlight the significance of 2,3-oxidosqualene, an intermediate metabolite of cholesterol biosynthesis, synthesized by SQLE and metabolized by lanosterol synthase (LSS), as a key regulator of ESCC progression. Mechanistically, the interaction between 2,3-oxidosqualene and vinculin enhances the nuclear accumulation of Yes-associated protein 1 (YAP), thereby increasing YAP/TEAD-dependent gene expression and accelerating both tumor growth and metastasis. In a 4-nitroquinoline 1-oxide (4-NQO)-induced ESCC mouse model, overexpression of Sqle resulted in accelerated tumorigenesis compared to wild-type controls, highlighting the pivotal role of SQLE in vivo. Furthermore, elevated SQLE expression in ESCC patients correlates with a poorer prognoses, suggesting potential therapeutic avenues for treatment. In conclusion, our study elucidates the oncogenic function of 2,3-oxidosqualene as a naturally occurring metabolite and proposes modulation of its levels as a promising therapeutic strategy for ESCC.

A YAP-derived peptide blocks YAP-TEAD signaling and suppresses cell proliferation

Yes-associated protein (YAP), a pivotal transcriptional co-activator in cell growth regulation, exerts its function through interactions with transcriptional factors like TEAD. Ectopic activation of YAP causes excessive cell proliferation, leading to multiple human diseases, including cancers. However, current pharmacological YAP inhibition lacks specificity and may have unintended effects, necessitating the development of direct YAP-derived inhibitors. In this study, we designed a novel YAP-derived peptide, TBDi, that specifically disrupted YAP-TEAD interaction and exhibited robust inhibition of TEAD activity. Mechanistically, TBDi directly binds to TEAD, blocking the physical interaction between YAP and TEAD. Transcriptomic analysis revealed that TBDi significantly altered gene expression profiles associated with TEAD activity, including downregulation of signature genes like CYR61 and CTGF. Functionally, TBDi emerged as a potent suppressor of cell proliferation, inhibiting cell proliferation to a degree comparable to YAP/TAZ knockdown. Altogether, our study not only identifies TBDi as a promising tool to block YAP-TEAD axis, but also offers insights for potential therapeutic interventions in diseases.

Discovery and biological evaluation of carborane-containing derivatives as TEAD auto palmitoylation inhibitors

Transcriptional enhanced associate domain (TEAD) proteins are key downstream effectors of the Hippo signaling pathway that play a crucial role in various cell processes including tissue development, regeneration, cell proliferation and cancer. TEADs contain a hydrophobic auto-palmitoylation pocket that can bind palmitic acid and stabilize TEADs from being degraded. Inhibitors targeting this palmitoylation pocket typically consist of hydrophobic pharmacophores. Carboranes is a cage-shaped molecule exhibiting superior hydrophobicity compared to adamantane or phenyl groups. Herein, we incorporated carborane into known TEAD inhibitors for better interaction with the hydrophobic palmitate pocket. Compounds 1f and 1l are identified as TEAD transcription inhibitors with strong anti-proliferation and anti-migration activities toward prostate cancer cell lines. They also significantly reduced TEAD-regulated downstream gene expressions.

Cell confluency affects p53 dynamics in response to DNA damage

The tumor suppressor protein p53 plays a key role in the cellular response to DNA damage. In response to DNA double-strand breaks (DSB), cultured cells exhibit oscillations of p53 levels, which impact gene expression and cell fate. The dynamics of p53 in vivo have only been studied in fixed tissues or using reporters for p53's transcriptional activity. Here we established breast tumors expressing a fluorescent reporter for p53 levels and employed intravital imaging to quantify its dynamics in response to DSB in vivo. Our findings revealed large heterogeneity among individual cells, with most cells exhibiting a single prolonged pulse. We then tested how p53 dynamics might change under high cell confluency, one factor that differs between cell culture and tissues. We revealed that highly confluent cultured breast cancer cells also show one broad p53 pulse instead of oscillations. Through mathematical modeling, sensitivity analysis, and live-cell imaging, we identified low levels of the phosphatase Wip1, a transcriptional target and negative regulator of p53, as a key contributor to these dynamics. Because high cell confluency better reflects the microenvironment of tissues, the impact of cell confluency on p53 dynamics may have important consequences for cancerous tissues responding to DNA damage-inducing therapies.

Engineered bone-targeting apoptotic vesicles as a minimally invasive nanotherapy for heterotopic ossification

Heterotopic Ossification (HO), refers to pathological extra skeletal bone formation, and there are currently no reliable methods except surgery to reverse these unexpected calcified tissues. Apoptotic vesicles (ApoEVs) are membrane-bound vesicles released by apoptotic cells, which are involved in metabolism regulation and intercellular communication. Due to its superior trauma-healing ability, the hard palate mucosa is expected to become an essential resource for tissue engineering. This work presents a minimally invasive nanotherapy based on an engineered apoEV. Briefly, apoEVs were extracted from hard palate mucosa and engineered with bone-targeting peptide SDSSD to treat HO. This engineered apoEV not only can achieve directed localization of heterotopic bones but also has the compelling dual function of promoting osteoclastic differentiation while inhibiting osteogenic differentiation. The underlying mechanism involves the activation of Hippo and Notch pathways, as well as the regulation of pyrimidine metabolism. We envision that this engineered apoEV may be a feasible and effective strategy for reversing HO.

Integration of focal adhesion morphogenesis and polarity by DOCK5 promotes YAP/TAZ-driven drug resistance in TNBC

YAP and TAZ are transcriptional co-activators that are inhibited by sequestration in the cytoplasm. Cellular signalling pathways integrate soluble, mechanical (cytoskeleton, adhesion), and geometric (cell size, morphology) cues to regulate the translocation of YAP/TAZ to the nucleus. In triple-negative breast cancer (TNBC) cells, both signalling and morphogenesis are frequently rewired, leading to increased YAP/TAZ translocation, which drives proliferation, invasion, and drug resistance. However, whether this increased YAP/TAZ translocation is due to alterations in upstream signalling events or changes in cell morphology remains unclear. To gain insight into YAP/TAZ regulation in TNBC cells, we performed multiplexed quantitative genetic screens for YAP/TAZ localisation and cell shape, enabling us to determine whether changes in YAP/TAZ localisation following gene knockdown could be explained by alterations in cell morphology. These screens revealed that the focal adhesion (FA)-associated RhoGEF DOCK5 is essential for YAP/TAZ nuclear localisation in TNBC cells. DOCK5-defective cells exhibit defects in FA morphogenesis and fail to generate a stable, polarised leading edge, which we propose contributes to impaired YAP/TAZ translocation. Mechanistically, we implicate DOCK5's ability to act as a RacGEF and as a scaffold for NCK/AKT as key to its role in FA morphogenesis. Importantly, DOCK5 is essential for promoting the resistance of LM2 cells to the clinically used MEK inhibitor Binimetinib. Taken together, our findings suggest that DOCK5's role in TNBC cell shape determination drives YAP/TAZ upregulation and drug resistance.

Auranofin resensitizes ferroptosis-resistant lung cancer cells to ferroptosis inducers

Lung cancer, a major cause of cancer-related mortality, has limited therapeutic options, especially for advanced cases. Ferroptosis, an iron-dependent form of cell death, is a potential therapeutic strategy for this disease; however, resistance mechanisms in the tumor microenvironment impede its effectiveness. Therefore, in this study, we aimed to investigate the efficacy of sulfasalazine (SAS), a ferroptosis inducer, and auranofin (AUR), a Food and Drug Administration-approved anti-inflammatory agent, combination to counteract ferroptosis resistance in lung cancer. SAS induced ferroptosis in vitro; however, its efficacy in vivo was limited, possibly because of factors, such as nutrient deprivation and high cell density, in the microenvironment that suppressed the activities of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), key regulators of ferroptosis resistance. Screening of 2483 drugs revealed AUR as a compound resensitizing the YAP/TAZ-deficient lung cancer cells to ferroptosis. Moreover, SAS and AUR combination significantly enhanced lipid peroxidation and reactive oxygen species accumulation, further driving ferroptosis in cells. This combination effectively inhibited tumor growth and enhanced survival in a murine lung cancer model. Overall, our findings suggest that AUR potentiates ferroptosis-based therapies, serving as an effective candidate to overcome ferroptosis resistance in lung cancer.

Dynamic structure and function of nuclear pore protein complex: Potential roles of lipid and lamins regulated nuclear membrane curvature

The nuclear pore complex (NPC), a massive and highly sophisticated protein assembly, forms a channel embedded in the nuclear envelope (NE) of eukaryotic cells. As a critical gateway, the NPC mediates the bidirectional transport of macromolecules between the cytoplasm and the nucleus. Here, we overview the structure and transport function of this protein complex, and highlight the selective barrier model of NPC transport functional modules. Nuclear membrane curvature (NMC) is a critical parameter for quantifying nuclear deformation. We discuss the mechanism by which NMC regulates dynamic NPC structure, function and distribution. Furthermore we highlight the role of two key factors, i.e. lipid composition and lamins distribution, in NPC dynamics while elucidating their regulatory mechanisms. The investigations on the dynamic structure and function of NPC modulated by NMC provide a new avenue for understanding the role of NPC in different pathological conditions. This knowledge could contribute to the development of novel therapeutic strategies.

3D pancreatic ductal adenocarcinoma desmoplastic model: Glycolysis facilitating stemness via ITGAV-PI3K-AKT-YAP1

The distinctive desmoplastic tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) is crucial in determining the stemness of tumor cells. And the conventional two-dimensional (2D) culture does not adequately mimic the TME. Therefore, a three-dimensional (3D) PDAC desmoplastic model was constructed using GelMA and HAMA, which provides benefits in terms of simulating both the main components (COL and HA) and the crosslinking of the extracellular matrix. We found that the 3D PDAC desmoplastic model upregulated the expression of the markers for stemness (NANOG and OCT4) and glycolysis (HK2 and GLUT2), and elevated the level of glycolysis, including increased glucose consumption and lactic acid production. Additionally, YAP1 played a crucial role in promoting glycolysis, which boosted stemness. Furthermore, RNA sequencing (RNA-seq) was employed to explore the underlying mechanisms associated with stemness within the 3D desmoplastic model. Subsequent KEGG pathway analysis indicated the activation of the PI3K-AKT signaling pathway, providing insights into the molecular processes at play. Using bioinformatics, qRT-PCR and western blot, we proposed that ITGAV-PI3K-AKT-YAP1 axis may account for the glycolysis mediated the stemness. Collectively, the 3D desmoplastic model may serve as a new platform for understanding the underlying mechanism by which the TME induces stemness.

Phosphoinositide signalling in cell motility and adhesion

Cell motility and adhesion are fundamental components for diverse physiological functions, including embryonic development, immune responses and tissue repair. Dysregulation of these processes can lead to a range of diseases, including cancer. Cell motility and adhesion are complex and often require regulation by an intricate network of signalling pathways, with phosphatidylinositol phosphates (PIPs) having a central role. PIPs are derived from phosphatidylinositol phosphorylation and are instrumental in mediating membrane dynamics, intracellular trafficking, cytoskeletal organization and signal transduction, all of which are crucial for cellular responses to environmental stimuli. Here we discuss the mechanisms through which PIPs modulate cell motility and adhesion by examining their roles at focal adhesions, within the cytoskeleton, at protein scaffolds and in the nucleus. By providing a comprehensive overview of PIP signalling, this Review underscores their significance in maintaining cellular homeostasis and highlights their potential as therapeutic targets in diseases characterized by aberrant cell motility and adhesion.

CDK4/6-mediated phosphorylation of DUB3 promotes YAP1 stability and hepatocellular carcinoma progression

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies, frequently characterized by high expression and activation of Yes-associated protein 1 (YAP1), a key effector in the Hippo signaling pathway. Despite its crucial role in HCC progression, effective therapies directly targeting YAP1 remain challenging, underscoring the need to explore the regulatory mechanisms underlying its aberrant expression and activation. In this study, we identify cyclin-dependent kinase 4 and 6 (CDK4/6) as uncharacterized regulators of YAP1 in HCC. Genetic ablation or pharmacological inhibition of CDK4/6 significantly destabilizes YAP1 and attenuates its oncogenic functions both in vitro and in vivo. Furthermore, we establish DUB3 as a bona fide deubiquitinase of YAP1. Mechanistically, CDK4/6 directly phosphorylates DUB3, enhancing its deubiquitinase activity towards YAP1, which promotes tumor growth and contributes to chemo-resistance in HCC. Collectively, our findings unveil the previously unrecognized function and significance of the CDK4/6-DUB3 axis in stabilizing YAP1 and provide a rationale for potential therapeutic interventions in the treatment of HCC.

Novel hydrogel-based cancer-on-a-chip models for growth of 3D multi-cellular structures and investigation of early angiogenesis in pancreatic ductal adenocarcinoma

Cancer-on-a-chip models have enormous potential for the study of tumour development events. Here, we investigated hydrogels of egg white (EW) and gelatin for growth of 3D multi-cellular structures and investigation of early angiogenesis inside microfluidic devices. We focused on pancreatic ductal adenocarcinoma (PDAC), a devastating gastrointestinal malignancy. EW/gelatin hydrogels were stiffer and showed porous globular structures compared to the fibrous network of collagen I molecules. PANC-1 cells preferentially formed significantly larger spheroids in collagen I than in EW/gelatin hydrogels, whilst cell aggregates in the shape of grape-like clusters were significantly larger and more abundant in EW/gelatin. Cells inside the aggregates showed active cell unions, secreted matrix, and formed active unions with the surrounding EW/gelatin hydrogel. Early stages of PDAC were recreated by co-culture of two different microenvironments, one for PANC-1 and another one for fibroblasts, for investigating the secretion of soluble angiogenic factors, which depended on the role of each factor in the angiogenic and tumorigenic processes. Overall, cancer cell proliferation and establishment of a tumour vasculature were favoured. This study demonstrates the importance of the microenvironment in tumour cells behaviour as well as the complex interplay between the different cells present in PDAC to establish a tumoural vasculature.

The cardiac glycoside periplocymarin sensitizes gastric cancer to ferroptosis via the ATP1A1-Src-YAP/TAZ-TFRC axis

BACKGROUND

Targeting ferroptosis vulnerabilities in tumors has become an increasingly promising therapeutic strategy. While the regulatory effects of natural products on ferroptosis are progressively being elucidated, the role of cardiac glycosides in modulating ferroptosis remains poorly understood.

PURPOSE

This study aims to investigate the ferroptosis-sensitizing effects of periplocymarin (PPM), a cardiac glycoside derived from the traditional plant Periploca sepium, and to elucidate the underlying molecular mechanisms.

METHODS

The effects of PPM on ferroptosis regulation were comprehensively assessed through functional assays, followed by sequencing analysis to identify associated signaling pathways. Subsequent mechanistic validation experiments were conducted to confirm the upstream and downstream regulatory components involved in this ferroptosis-modulating axis.

RESULTS

PPM induced slow and mild apoptosis in gastric cancer cells through the inhibition of glycolysis. However, when combined with ferroptosis inducers, it promoted rapid and robust ferroptosis. In vivo, PPM sensitized gastric cancer xenografts to cisplatin-induced ferroptosis with no observable cardiotoxicity or renal impairment. Mechanistically, PPM targeted the α1 subunit of the Na+/K+-ATPase (ATP1A1), leading to the activation of Src, which subsequently induced tyrosine phosphorylation of YAP/TAZ in a Hippo-independent manner, promoting their nuclear translocation. The YAP/TAZ-TEAD transcriptional complex directly bound to the TFRC promoter region between nucleotides 401-409 upstream of the transcription start site, thereby activating TFRC transcription. This resulted in increased iron influx, elevated lipid peroxidation, and heightened sensitivity to ferroptosis. Notably, ATP1A1 was essential for ferroptosis resistance, as its knockdown mimicked the sensitizing effect of PPM on ferroptosis. Moreover, the oncogenic Src-YAP/TAZ-TFRC axis may have represented a ferroptosis vulnerability and a potential biomarker in ferroptosis therapy for cancer. Importantly, other cardiac glycosides targeting Na+/K+-ATPase, such as digitoxin and bufalin, also enhanced ferroptosis sensitivity in gastric cancer cells through activation of YAP/TAZ signaling.

CONCLUSION

Our findings establish the cardiac glycoside PPM as a novel ferroptosis sensitizer that targets ATP1A1 to activate the Src-YAP/TAZ-TFRC axis, providing mechanistic insights for repurposing cardiac glycosides as ferroptosis modulators in precision combinatorial cancer therapy.

The mechanism of YAP/TAZ transactivation and dual targeting for cancer therapy

Transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) play key roles in cancers through transcriptional outputs. However, their transactivation mechanisms remain unclear, and effective targeting strategies are lacking. Here, we show that YAP/TAZ possess a hydrophobic transactivation domain (TAD). TAD knockout prevents tumor establishment due to growth defects and enhances immune attack. Mechanistically, TADs facilitate preinitiation complex (PIC) assembly by recruiting the TATA-binding protein-associated factor 4 (TAF4)-dependent TFIID complex and enhance RNA polymerase II (Pol II) elongation through mediator complex subunit 15 (MED15)-dependent mediator recruitment for the expressions of oncogenic/immune-suppressive programs. The synthesized peptide TJ-M11 selectively disrupts TAD interactions with MED15 and TAF4, suppressing tumor growth and sensitizing tumors to immunotherapy. Our findings demonstrate that YAP/TAZ TADs exhibit dual functions in PIC assembly and Pol II elongation via hydrophobic interactions, which represent actionable targets for cancer therapy and combination immunotherapy.

Long non-coding RNA LRTOR drives osimertinib resistance in non-small cell lung cancer by boosting YAP positive feedback loop

The therapeutic efficacy of osimertinib (OSI) in EGFR-mutant lung cancer is ultimately limited by the onset of acquired resistance, of which the mechanisms remain poorly understood. Here, we identify a novel long non-coding RNA, LRTOR, as a key driver of OSI resistance in non-small cell lung cancer (NSCLC). Clinical data indicate that elevated LRTOR expression correlates with poor prognosis in OSI-resistant patients. Functionally, LRTOR promotes tumor growth and confers OSI resistance both in vitro and in vivo. Mechanistically, LRTOR shields YAP from LATS-mediated phosphorylation at Ser127 and Ser381, preventing its proteasomal degradation. Furthermore, LRTOR facilitates the interaction between YAP and KCMF1, promoting K63-linked ubiquitination, nuclear translocation of YAP, and formation of the YAP/TEAD1 transcriptional complex, which in turn triggers the transcription of LRTOR, establishing a positive feedback loop that amplifies oncogenic signaling of YAP and consequently induces OSI resistance. LRTOR depletion by siRNA restores OSI sensitivity in resistant tumors, as demonstrated in patient-derived organoid xenograft models. Our findings unveil LRTOR as a central regulator of OSI resistance in NSCLC and propose it as a promising therapeutic and prognostic target for overcoming acquired OSI resistance in EGFR-mutant lung cancer.

Targeting the Hippo Pathway in Breast Cancer: A Proteomic Analysis of Yes-Associated Protein Inhibition

The dysregulation of the Hippo signaling pathway leads to the aberrant activation of oncogenic YAP and TAZ, driving tumor progression. In breast cancer, this disruption promotes proliferation and metastasis. This study investigates the effects of CA3, a selective YAP inhibitor, on the proteome of triple-negative breast cancer MDA-MB-231 and luminal-A-like MCF7 cells. Proteomic changes were analyzed via nano-LC-MS/MS, while cytotoxicity, apoptosis, and autophagy were assessed through WST-1 assays, flow cytometry, and Western blot analyses. Bioinformatics tools were employed to identify enriched pathways. MDA-MB-231 cells exhibited an increased expression of DNA repair proteins (p < 0.05), indicating a compensatory response to maintain genomic stability. In contrast, MCF7 cells showed a downregulation of DNA repair factors (p < 0.005). Additionally, metabolic reprogramming was apparent in MCF7 cells (p < 0.001). Apoptosis assays revealed a rise in cell death, while cell cycle analysis indicated pronounced G1-phase arrest in MDA-MB-231 cells (p < 0.01). Moreover, autophagic suppression was particularly evident in MCF7 cells. This study, for the first time, provides evidence that breast cancer subtypes exhibit distinct dependencies on YAP-driven pathways, revealing potential therapeutic vulnerabilities. Targeting Hippo signaling alongside DNA repair in triple-negative breast cancer or combining YAP inhibition with metabolic blockade in luminal breast cancer holds significant potential to enhance treatment efficacy.

Mechanisms of bone regeneration repair and potential and efficacy of small molecule drugs

Bone regeneration and repair is a complex physiological process of bone formation. To date, existing research has greatly enhanced our understanding of bone regeneration and repair, achieving significant success in treating bone injuries. However, extensive bone defects, bone nonunion, and metabolic bone diseases remain incompletely solved challenges in modern medicine. With the emergence of High-Throughput Screening (HTS) technology, previous studies have identified numerous small molecule compounds with potential for inducing bone formation and enhancing bone metabolism. However, the effects of these small molecules on bone regeneration and repair through related signaling pathways have not been systematically elaborated. Therefore, in this literature review, we focus on summarizing the classical signaling pathways affecting bone regeneration and repair, as well as the research progress and applications of related small molecule drugs.

Celastrol loaded nanocomplex for painless tumor therapy via YAP inhibition

Cancer-related pain is prevalent and severely impairs patients' quality of life. However, conventional cancer therapies primarily target tumor cell destruction, often overlooking the management of cancer pain. Thus, there is an immediate necessity to develop therapeutic agents that can both suppress tumor growth and alleviate cancer pain. In this study, we report a celastrol (CEL)-based nanocomposites (PDA-BSA-MnO2-CEL) for pain-less cancer immunotherapy. Results from in vitro and in vivo experiments demonstrate the efficacy and mechanism of the nanocomposites in pain-less immunotherapy. MnO2 and CEL induce immunogenic cell death (ICD), mediating immunotherapy. Additionally, CEL significantly reduces the secretion of the immunosuppressive factor Yes-associated protein (YAP) within the tumor microenvironment, thereby enhancing the efficacy of immunotherapy. The downregulation of YAP leads to reduced expression of vascular endothelial growth factor (VEGF), inhibiting tumor growth and decreasing activation of the pain-associated VEGF receptor 1 (VEGFR1), thus providing an analgesic effect. Moreover, CEL reduces inflammatory pain by lowering levels of inflammatory factors in tumors. The design of this nanocomposites system integrates immunotherapy with cancer pain inhibition, offering a novel approach to patient-centered tumor therapy.

Peptide-Modified Lipid Nanoparticles Boost the Antitumor Efficacy of RNA Therapeutics

RNA therapeutics offer a promising approach to cancer treatment by precisely regulating cancer-related genes. While lipid nanoparticles (LNPs) are currently the most advanced nonviral clinically approved vectors for RNA therapeutics, their antitumor efficacy is limited by their unspecific hepatic accumulation after systemic administration. Thus, there is an urgent need to enhance the delivery efficiency of LNPs to target tumor-residing tissues. Here, we conjugated the cluster of differentiation 44 (CD44)-specific targeting peptide A6 (KPSSPPEE) to the cholesterol of LNPs via PEG, named AKPC-LNP, enabling specific tumor delivery. This modification significantly improved delivery to breast cancer cells both in vitro and in vivo, as shown by flow cytometry and confocal microscopy. We further used AKPC-siYT to codeliver siRNAs targeting the transcriptional coactivators YAP and TAZ, achieving potent gene silencing and increased cell death in both 2D cultures and 3D tumor spheroids, outperforming unmodified LNPs. In a breast tumor cell xenografted zebrafish model, systemically administered AKPC-siYT induced robust silencing of YAP/TAZ and downstream genes and significantly enhanced tumor suppression compared to unmodified LNPs. Additionally, AKPC-siYT effectively reduced proliferation in prostate cancer organoids and tumor growth in a patient-derived xenograft (PDX) model. Overall, we developed highly efficient AKPC-LNPs carrying RNA therapeutics for targeted cancer therapy.

Hyperactivated YAP1 is essential for sustainable progression of renal clear cell carcinoma

The most notable progress in renal clear cell carcinoma (ccRCC) in the past decades is the introduction of drugs targeting the VHL-HIF signaling pathway-associated angiogenesis. However, mechanisms underlying the development of VHL mutation-independent ccRCC are unclear. Here we provide evidence that the disrupted Hippo-YAP signaling contributes to the development of ccRCC independent of VHL alteration. We found that YAP1 and its primary target genes are frequently upregulated in ccRCC and the upregulation of these genes is associated with unfavorable patient outcomes. Research results derived from our in vitro and in vivo experimental models demonstrated that, under normoxic conditions, hyperactivated YAP1 drives the expression of FGFs to stimulate the proliferation of tumor and tumor-associated endothelial cells in an autocrine/paracrine manner. When rapidly growing cancer cells create a hypoxic environment, hyperactivated YAP1 in cancer cells induces the production of VEGF, which promotes the angiogenesis of tumor-associated endothelial cells, leading to improved tumor microenvironment and continuous tumor growth. Our study indicates that hyperactivated YAP1 is essential for maintaining ccRCC progression, and targeting the dual role of hyperactivated YAP1 represents a novel strategy to improve renal carcinoma therapy.

Extracellular matrix stiffness: mechanisms in tumor progression and therapeutic potential in cancer

Tumor microenvironment (TME) is a complex ecosystem composed of both cellular and non-cellular components that surround tumor tissue. The extracellular matrix (ECM) is a key component of the TME, performing multiple essential functions by providing mechanical support, shaping the TME, regulating metabolism and signaling, and modulating immune responses, all of which profoundly influence cell behavior. The quantity and cross-linking status of stromal components are primary determinants of tissue stiffness. During tumor development, ECM stiffness not only serves as a barrier to hinder drug delivery but also promotes cancer progression by inducing mechanical stimulation that activates cell membrane receptors and mechanical sensors. Thus, a comprehensive understanding of how ECM stiffness regulates tumor progression is crucial for identifying potential therapeutic targets for cancer. This review examines the effects of ECM stiffness on tumor progression, encompassing proliferation, migration, metastasis, drug resistance, angiogenesis, epithelial-mesenchymal transition (EMT), immune evasion, stemness, metabolic reprogramming, and genomic stability. Finally, we explore therapeutic strategies that target ECM stiffness and their implications for tumor progression.

"Putting the cart before the horse": an update on promiscuous gene fusions in soft tissue tumors

The ever-increasing availability and affordability of molecular genetic testing has revolutionized our understanding of the pathogenesis and proper classification of soft tissue tumors but has also brought new challenges. As is known, many soft tissue tumors harbor gene fusion events, and while it was initially thought that individual entities would be defined by single, specific fusions, it quickly became clear that some entities could be caused by several different fusion events (e.g., EWSR1::FLI1, EWSR1::ERG, EWSR1:FEV and others in Ewing sarcoma). More recently, it has become apparent that these fusion events themselves are "promiscuous", appearing in more than one discrete entity (e.g., EWSR1::CREB1 in clear cell sarcoma, angiomatoid fibrous histiocytoma and others). This review article will briefly discuss the best known examples of genetic promiscuity, the EWSR1/FUS::ATF1/CREB1 and ETV6::NTRK3 fusions, and more comprehensively cover recently discovered and less well-known examples of genetic promiscuity, including EWSR1::WT1, MALAT1::GLI1, YAP1::TFE3 and fusions involving members of the FET and ETS gene families.

CDK5 interacts with MST2 and modulates the Hippo signalling pathway

MST2 (STK3) is a major upstream kinase in the Hippo signalling pathway, an evolutionary conserved pathway in regulation of organ size, self-renewal and tissue homeostasis. Its downstream effectors are the transcriptional regulators YAP and TAZ. This pathway is regulated by a variety of factors, such as substrate stiffness or cell-cell contacts. Using a yeast two-hybrid screen, we detected a novel interaction between the kinases MST2 and CDK5, which we further confirmed by co-immunoprecipitation experiments. Cyclin-dependent kinase 5 (CDK5) is an unusual member of the family of cyclin-dependent kinases, involved in tumour growth and angiogenesis. Although a link between CDK5 and Hippo has been previously postulated, the mode of action is still elusive. Here, we show that knockdown of CDK5 causes reduced transcriptional activity of YAP and that CDK5 influences the phosphorylation levels of the Hippo upstream kinase LATS1. Moreover, a phosphoproteomics approach revealed that CDK5 interferes with the phosphorylation of DLG5, another upstream kinase, which regulates the Hippo pathway. Hence, CDK5 seems to act as a signalling hub for integrating the Hippo pathway and other signalling cascades. These interactions might have important implications for the use of CDK5 inhibitors, which are already in clinical use for tumour diseases.

Phospho-cofilin predicts efficiency of Fasudil for oral squamous cell carcinoma treatment through Yes-associated protein inhibition

OBJECTIVES

This study evaluates Fasudil, a Rho-associated coiled-coil-containing protein kinase (ROCK) inhibitor, for its potential to inhibit oral squamous cell carcinoma (OSCC) growth and explores phospho-cofilin as a potential biomarker for prediction treatment efficiency of Fasudil in OSCC.

DESIGN

A cohort of 109 OSCC patients provided tissue samples for phospho-cofilin expression analysis and survival analysis. The study examined the effect of Fasudil on OSCC cell lines HSC-3, UM1, and CAL33, assessing tumor growth inhibition through various in vitro and in vivo experiments. ROCK inhibition response and downstream mechanisms were explored by RNA sequencing, q-PCR, and immunofluorescence.

RESULTS

High phospho-cofilin expression in OSCC tissues correlated with poor patient outcomes and was a reliable biomarker for ROCK activity. Fasudil inhibited growth in OSCC cell lines, particularly those with high phospho-cofilin expression. ROCK inhibition led to downregulation of Yes-associated protein (YAP) activity, resulting in suppressed tumor proliferation and increased apoptosis both in vitro and in vivo.

CONCLUSIONS

Inhibition of ROCK/phospho-cofilin/YAP by Fasudil could suppress OSCC proliferation, while phospho-cofilin served as a potential biomarker of OSCC.

Phase separation of EEF1E1 promotes tumor stemness via PTEN/AKT-mediated DNA repair in hepatocellular carcinoma

This study aimed to investigate the associations of liquid-liquid phase separation (LLPS) and tumor stemness in hepatocellular carcinomas (HCC). LLPS-related genes were extracted from DrLLPS, LLPSDB and PhaSepDB databases. Stemness index (mRNAsi) was calculated based on the data from TCGA and Progenitor Cell Biology Consortium. Through some series of bioinformatics methods, we first found that stemness index mRNAsi was associated with worse survival outcomes, immune infiltration and therapy sensitivity in HCC. G2M checkpoint and DNA repair pathways were significantly activated with high mRNAsi. Totally, 71 differentially expressed LLPS genes in HCC were correlated with mRNAsi, and a mRNAsi-associated LLPS gene signature (KPNA2, EEF1E1 and ATIC) was identified to predict prognosis for HCC patients. mRNAsi-associated LLPS genes contributed to cluster HCC patients into four molecular clusters that markedly differed on survival, immune infiltration and therapy sensitivity. Further in vivo and in vitro experiments showed that EEF1E1 was highly expressed in HepG2 and HCCLM3 cells, and EEF1E1 silencing observably inhibited tumor cell growth, liver cancer stem cells (CSCs) markers (CD133, EpCAM and SOX2) expression, enhanced DNA damage marker γH2AX expression by activating PTEN/AKT pathway. EEF1E1 could undergo LLPS condensates, and roles of EEF1E1 on tumor cells were partly reversed after inhibiting LLPS using 1, 6-hexanediol. In conclusion, EEF1E1 was identified as a phase separation protein and involves in tumor stemness and DNA damage repair in HCC. EEF1E1 and its LLPS condensate may be novel targets to elaborate the underlying mechanisms of CSCs propagation in HCC.

DROSOPHILA: THE CENTURY-LONG FLIGHT FROM THE WILD TO THE PATIENT

Background: Evolutionary conservation of key biological pathways between the fruit fly Drosophila melanogaster and humans and reduced genetic redundancy have long made flies a valuable genetic model organism. Thanks to the arsenal of sophisticated genetic tools developed and refined by the fly community, the use of Drosophila has expanded well beyond basic research. From the fundamental notion that genes are located on chromosomes to modeling human complex diseases such as cancer and neurological disorders, to designing fly "avatar" lines that precisely reproduce the specific mutations found in single cancer patients for personalized medicine, Drosophila continues to fuel biomedical advances. Numerous examples of drug testing in flies have yielded novel drug candidates, new uses for approved drugs, and applications for rapid drug optimization in modern approaches combining biology with medicinal chemistry. Thanks to the effectiveness of "fly pharmacology" approaches, Drosophila is also proficiently used to study the mechanism of action of environmental pollutants that represent a serious concern to human health. This review traces the history of some of the main advances in Drosophila biomedical and cancer research.

A novel clinically relevant antagonistic interplay between prolactin and oncogenic YAP-CCN2 pathways as a differentiation therapeutic target in breast cancer

Cellular differentiation limits cellular plasticity allowing cells to attain their specialized functional characteristics and phenotypes, whereas loss of differentiation is a hallmark of cancer. Thus, characterizing mechanisms underlying differentiation is key to discover new cancer therapeutics. We report a novel functional antagonistic relationship between the prolactin (PRL)/prolactin receptor (PRLR) differentiation pathway and YAP-CCN2 oncogenic pathway in normal mammary epithelial cells and breast cancer cells that is essential for establishing/maintaining acinar morphogenesis, cell-cell junctions and the intracellular localization of apical-basal polarity protein complexes (Par, Crumb and Scrib). Importantly, using CRISPR knockout of the PRLR in MCF7, HR+ breast cancer cells, further revealed that the negative relationship between PRL/PRLR pathway and YAP-CCN2 pathway is critical in suppressing luminal-to-basal stem-like lineage plasticity. Furthermore, the clinical relevance of this interplay was evaluated using bioinformatics approaches on several human datasets, including samples from normal breast epithelium, breast cancer, and 33 other cancer types. This analysis revealed a positive correlation between PRLR and the YAP suppressor Hippo pathway and a co-expression gene network driving favourable patients' survival outcomes in breast cancer. The therapeutic potential of this interplay was also evaluated in vitro using MDA-MB-231 cells, a preclinical model of human triple-negative breast cancer, where treatment with PRL and Verteporfin, an FDA-approved pharmacological YAP-inhibitor, alone or their combination suppressed the expression of the mesenchymal marker vimentin and the stem cell marker CD44 as well as reduced their Ki67 proliferative marker expression. Collectively, our results emphasize the pro-differentiation role of PRL/PRLR pathway in mammary and breast cancer cells and highlight that promoting PRL/PRLR signaling while inhibiting the YAP-CCN2 oncogenic pathway can be exploited as a differentiation-based combination therapeutic strategy in breast cancer.

PDLIM3 Regulates Migration and Invasion of Head and Neck Squamous Cell Carcinoma via YAP-Mediated Epithelial-Mesenchymal Transition

Despite significant progress in characterizing the omics landscape of head and neck squamous cell carcinoma (HNSCC), the development of precision therapies remains limited. One key factor contributing to this challenge is the marked molecular heterogeneity of HNSCC. Further investigation of molecular profiles within HNSCC may facilitate the improvement in more effective precision treatments. Here, we focus on the dysregulation of PDZ and LIM domain protein 3 (PDLIM3) in HNSCC. The expression levels of PDLIM3 were analyzed using public datasets to assess its potential role in tumor progression. We found that PDLIM3 was downregulated in pan-cancer and HNSCC. The prognostic significance of PDLIM3 was evaluated through tissue microarray, and the downregulation of PDLIM3 was correlated with poor HNSCC prognosis. Investigating the implications of PDLIM3 for tumor metastatic ability in vitro, we found that PDLIM3 suppressed the migration and invasion of HNSCC, accompanied by partially impeding the process of epithelial-mesenchymal transition (EMT). Furthermore, PDLIM3 inhibited the transcriptional activity of Yes-associated protein (YAP), suggesting that YAP may be involved in the PDLIM3-mediated suppression of HNSCC metastatic ability. Our findings identify a potential signaling axis wherein PDLIM3 regulates YAP-EMT, thereby influencing tumor metastatic ability, and suggest the potential role of PDLIM3 as a tumor suppressor and prognostic biomarker for HNSCC.

Glycolysis-related lncRNA FTX upregulates YAP1 to facilitate colorectal cancer progression via sponging miR-215-3p

Increased evidence reveals that glycolysis is one of the key metabolic hallmarks of cancer cells. However, the roles of lncRNA FTX in energy metabolism and cancer progression remain unclear. In this study we aim to show that lncRNA FTX was significantly upregulated in cancer tissues and serum of CRC patients and CRC cell lines. Function study indicated that it could promote aerobic glycolysis, cell proliferation, migration and invasion in colorectal cancer cells. Further mechanistic studies showed, lncRNA FTX was found to function as a sponge for miR-215-3p, which reduced the ability of miR-215-3p to repress the YAP1 oncoprotein. Additionally, a negative correlation was observed between lncRNA FTX and miR-215-3p expression, and the knockdown of lncRNA FTX or miR-215-3p overexpression yielded opposite effects. In conclusion, this study demonstrates that FTX could directly combine with miR-215-3p as a competitive endogenous RNA, thus promoting the aerobic glycolysis and progression of CRC in vitro and in vivo.

The Role of Connections Between Cellular and Tissue Mechanical Elements and the Importance of Applied Energy in Mechanotransduction in Cancerous Tissue

In the presence of cellular mutations and impaired mechanisms of energy transmission to the attached cells and tissues, excess energy is available to upregulate some of the mechanotransduction pathways that maintain cell and tissue structure and function. The ability to transfer applied energy through integrin-mediated pathways, cell ion channels, cell membrane, cytoskeleton-nucleoskeleton connections, cell junctions, and cell-extracellular matrix attachments provides an equilibrium for energy storage, transmission, and dissipation in tissues. Disruption in energy storage, transmission, or dissipation via genetic mutations blocks mechanical communication between cells and tissues and impairs the mechanical energy equilibrium that exists between cells and tissues. This results in local structural changes through altered regulatory pathways, which produce cell clustering, collagen encapsulation, and an epithelial-mesenchymal transition (EMT), leading to increased cellular motility along newly reorganized collagen fibers (fibrosis). The goal of this review is to postulate how changes in energy transfer between cells and the extracellular matrix may alter local energy equilibrium and mechanotransduction pathways. The changes along with cellular mutations lead to cell and ECM changes reported in cancer, which is postulated to modify mechanical equilibria between cells and their ECM. This leads to uncontrolled cancer cellular proliferation and collagen remodeling.

Elevated VRK1 levels after androgen deprivation therapy promote prostate cancer progression by upregulating YAP1 expression

PURPOSE

Vaccinia-related kinase 1 (VRK1) is a serine-threonine kinase involved in the proliferation and migration of various cancer cells. However, its role in prostate cancer (PCa), particularly in the development of therapeutic resistance, remains unclear.

METHODS

We established an androgen-independent PCa cell line derived from LNCaP prostate cancer cells and conducted transcriptome and proteome sequencing together with bioinformatic analyses of large clinical sample databases to investigate the potential role of VRK1 in PCa progression. The correlation between VRK1 and androgen receptor (AR) signaling was evaluated under simulated clinical treatment conditions. The effects of VRK1 on cell proliferation were assessed in vitro and in vivo using Cell Counting Kit-8 and colony formation assays. Additionally, proteome and transcriptome sequencing, combined with rescue experiments were performed to explore VRK1-regulated signaling pathways related to cell proliferation and therapeutic resistance.

RESULTS

VRK1 expression was elevated during the progression of androgen-dependent prostate cancer to castration-resistant prostate cancer under therapeutic conditions, and high VRK1 expression was associated with a poor prognosis in patients with PCa. VRK1 was regulated by AR signaling, and its silencing suppressed PCa cell proliferation both in vitro and in vivo. VRK1 drove cell proliferation and therapeutic resistance in PCa by modulating yes-associated protein 1 (YAP1).

CONCLUSIONS

VRK1 serves as a prognostic marker in PCa, regulated by AR signaling. VRK1 depletion inhibited cell proliferation both in vitro and in vivo, while elevated VRK1 upregulated YAP1, promoting cell proliferation and therapeutic resistance.

[Research Advances in Targeting the YAP/TAZ Signaling Pathway to Improve Cancer Immunotherapy]

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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The Hippo pathway effector YAP inhibits NF-κB signaling and ccRCC growth by opposing ZHX2

The prevailing view in the cancer field is that Hippo (Hpo) signaling pathway functions as a tumor suppressor pathway by blocking the oncogenic potential of the pathway effectors Yes1-associated transcriptional regulator (YAP)/transcriptional coactivator with PDZ-binding motif. However, YAP can also function as a context-dependent tumor suppressor in several types of cancer including clear cell renal cell carcinomas (ccRCCs). We find that, in addition to inhibiting hypoxia-inducible factor 2α, a major oncogenic driver in Von Hippel-Lindau-/- ccRCC, YAP also blocks nuclear factor κB (NF-κB) signaling in ccRCC to inhibit cancer cell growth under conditions where hypoxia-inducible factor 2α is dispensable. Mechanistically, YAP inhibits the expression of Zinc fingers and homeoboxes 2 (ZHX2), a Von Hippel-Lindau substrate and critical cofactor of NF-κB in ccRCC. Furthermore, YAP competes with ZHX2 for binding to the NF-κB subunit p65. Consequently, elevated nuclear YAP blocks the cooperativity between ZHX2 and the NF-κB subunit p65, leading to diminished NF-κB target gene expression. Pharmacological inhibition of Hpo kinase blocked NF-κB transcriptional program and suppressed ccRCC cell growth, which can be rescued by overexpression of ZHX2 or p65. Our study uncovers a crosstalk between the Hpo and NF-κB/ZHX2 pathways and its involvement in ccRCC growth inhibition, suggesting that targeting the Hpo pathway may provide a therapeutical opportunity for ccRCC treatment.

Antitumor potential of polyamines in cancer

The dysregulation of polyamines in tumors has made polyamine metabolism an appealing target for cancer therapy. Gene mutations drive the reprogramming of polyamine metabolism in tumors, presenting promising opportunities for clinical treatment. The proposed strategies involve inhibiting polyamine biosynthesis while also targeting the polyamine transport system as antitumor approaches. A growing number of drugs aimed at polyamine biosynthesis and transport systems are undergoing clinical trials. Polyamine metabolism plays a role in regulating cancer signaling pathways, suggesting potential combination therapies for cancer treatment. Furthermore, supplemental polyamine substances have demonstrated antitumor activity, indicating that combining polyamines with downstream targets or immunotherapy could offer significant clinical benefits. These discoveries open new avenues for leveraging polyamine metabolism in anticancer therapy.

Mechanism of Lung Fibrosis Caused by Rare Earth Samarium Oxide Through Hippo Signaling Pathway and the Intervention of GBE

With the ongoing advancement and utilization of rare earth elements, human and environmental exposure to these materials has risen substantially. Samarium oxide (Sm₂O₃), a rare earth element, has been shown to induce pulmonary fibrosis, but the mechanisms are not clear. This study aimed to investigate the primary mechanisms by which rare earth Sm2O3 contributes to pulmonary fibrosis in relation to the Hippo signaling pathway and to assess the interventional effects of Ginkgo biloba extract (GBE). A mouse model of pulmonary fibrosis was established through intratracheal administration of a Sm2O3 suspension, while human embryonic lung fibroblasts were also treated for intervention studies. The results indicated that compared with the control group, the expression of SAV1, LATS1/2, MST1, YAP1, and TEAD1 genes was significantly up-regulated in the Sm2O3 group, while the expression of TAZ gene was down-regulated. Additionally, the levels of p-LATS1, LATS1, YAP, and p-YAP were elevated, suggesting that Sm2O3 promotes pulmonary fibrosis through an imbalance and abnormal regulation of the Hippo signaling pathway. Furthermore, human embryonic lung fibroblasts stained with Sm2O3 were treated with different dose gradients of GBE, and the expression level of p-LATS1, LATS1, YAP, and p-YAP was decreased as the dose of Sm2O3 increased, whereas treatment with GBE increased the expression of these proteins. GBE can mitigate the fibrotic response induced by Sm₂O₃ exposure. These findings demonstrate that Sm₂O₃ induces pulmonary fibrosis, at least in part, by inactivating the Hippo signaling pathway. Further investigation is warranted to fully elucidate the protective mechanisms of GBE and its therapeutic potential in this context.

A skin organoid-based infection platform identifies an inhibitor specific for HFMD

The EV-A71 poses a serious threat to the health and lives of children. The EV-A71 can be transmitted by direct and indirect skin contact. Therefore, there is an urgent need to create novel skin models using human-derived cells to study the biology and pathogenesis of the virus and facilitate drug screening. Here, we use human induced pluripotent stem cells-derived skin organoids (hiPSC-SOs) as a model for EV-A71 infection and find that multiple cell types within the skin organoids, including epidermal cells, hair follicle cells, fibroblasts, and nerve cells, express EV-A71 receptors and are susceptible to EV-A71 infection. We elucidate the specific response of different cell types to EV-A71 and reveal that EV-A71 infection can degrade extracellular collagen and affect fibroblasts. We find that EV-A71 can mediate epidermal cell damage through autophagy and Integrin/Hippo-YAP/TAZ signaling pathways, thereby promoting hyperproliferation of progenitor cells. Based on this finding, we identify an autophagy-associated protein as a drug target of EV-A71 and discover an EV-A71 replication inhibitor. Altogether, these data suggest that hiPSC-SOs can be used as an infectious disease model to study skin infectious diseases, providing a valuable resource for drug screening to identify candidate virus therapeutics.

Microbial metabolites control self-renewal and precancerous progression of human cervical stem cells

Cervical cancer is the fourth most common female cancer, with the uterine ectocervix being the most commonly affected site. However, cervical stem cells, their differentiation, and their regulation remain poorly understood. Here, we report the isolation of a population enriched for human cervical stem cells and their regulatory mechanisms. Using single-cell RNA sequencing, we characterize the cellular heterogeneity of the human ectocervix and identify cluster-specific cell surface markers. By establishing normal and precancerous cervical organoids and an intralingual transplantation system, we show that ITGB4 and CD24 enable enrichment of human and murine ectocervical stem cells. We discover that Lactobacilli-derived lactic acid regulates cervical stem cells' self-renewal and early tumorigenesis through the PI3K-AKT pathway and YAP1. Finally, we show that D-lactic acid suppresses growth of normal and precancerous organoids, while L-lactic acid does not. Our findings reveal roles of human cervical stem cells and microbial metabolites in cervical health and diseases.

Gracillin suppresses cancer progression through inducing Merlin/LATS protein-protein interaction and activating Hippo signaling pathway

Gene therapy, epigenetic therapies, natural compounds targeted therapy, photodynamic therapy, nanoparticles, and precision medicines are becoming available to diagnose and treat cancer. Gracillin, a natural steroidal saponin extracted from herbs, has shown potent efficacy against a range of malignancies. In this study, we investigated the molecular anticancer mechanisms of gracillin. We showed that gracillin dose-dependently suppressed proliferation, migration, and invasion in breast cancer, liver cancer, and glioblastoma cells with IC50 values around 1 μM, which were associated with MST-independent activation of Hippo signaling pathway and subsequent decreased YAP activity. We demonstrated that gracillin activated the Hippo signaling by inducing Merlin/LATS protein-protein interaction (PPI). A competitive inhibitory peptide (SP) derived from the binding interface of the PPI, disrupted the interaction, abolishing the anticancer activity of gracillin. In nude mice bearing MDA-MB-231, HCCLM3, or U87MG xenograft tumor, administration of gracillin (5, 10 mg·kg-1·d-1, i.g. for 21 days) dose-dependently suppressed the tumor growth, associated with the induced Merlin/LATS PPI, activated Hippo signaling, as well as decreased YAP activity in tumor tissues. Our data demonstrate that gracillin is an efficacious therapeutic agent for cancer treatment, induction of Merlin/LATS PPI might provide proof-of-concept in developing therapeutic agent for cancer treatment.

Integrative research on the mechanisms of acupuncture mechanics and interdisciplinary innovation

As a traditional therapeutic approach, acupuncture benefits from modern biomechanics, which offers a unique perspective for understanding its mechanisms by investigating the mechanical properties of biological tissues and cells under force, deformation, and movement. This review summarizes recent advancements in the biomechanics of acupuncture, focusing on three main areas: the mechanical effects of acupuncture, the transmission mechanisms of mechanical signals, and the personalization and precision of acupuncture treatments. First, the review introduces the structural basis of the tissues involved in acupuncture; analyzes the mechanical responses of the skin, dermis, and subcutaneous tissues from needle insertion to point activation; and discusses how these responses impact acupuncture efficacy. Second, the phenomenon of mechanical coupling during acupuncture is discussed in detail, especially the role of connective tissues, including the wrapping and self-locking of collagen fibers, the remodeling of the cytoskeleton and the regulation of mitochondrial function triggered by acupuncture. Third, this article examines the mechanisms of mechanical signal transmission in acupuncture, explaining how mechanosensitive ion channels are activated during the procedure and subsequently initiate a cascade of biochemical responses. Finally, the review highlights the numerical simulation methods used in acupuncture, including the mechanical modeling of skin tissues, the exploration of the mechanical mechanisms of acupuncture, and visualization studies of the needling process. By integrating multidisciplinary research findings, this paper delves into the entire mechanical process of acupuncture, from skin penetration to point stimulation, and analyzes tissue responses to provide a solid theoretical foundation for the scientific study of acupuncture. In addition, directions for future research to further refine acupuncture techniques for clinical applications are proposed.

USP43 drives cervical carcinoma progression through regulation of the Hippo/TAZ pathway

BACKGROUND

Cervical carcinoma (CC) poses significant health challenges, with its pathogenesis not fully understood. While ubiquitin specific peptidase 43 (USP43) is implicated in various cancers, its role in CC and regulation of the Hippo/Transcriptional Co-Activator With PDZ-Binding Motif (TAZ) pathway remain unexplored. This study examines USP43's impact on CC progression and its interaction with TAZ.

METHODS

USP43 expression levels in CC tissues and cell lines were assessed using reverse transcription real-time polymerase chain reaction (RT-qPCR) and Western blot. The effects of USP43 silencing on cell proliferation, migration, and invasion were evaluated through cell counting Kit-8 (CCK-8), 5-ethynyl-2'deoxyuridine (EdU), colony formation, and transwell assays. Immunofluorescence staining and co-immunoprecipitation (Co-IP) assays were used to explore the interaction between USP43 and TAZ. Polyubiquitination assays were performed to evaluate ubiquitination and stability of TAZ, and cycloheximide (CHX) chase experiments determined the half-life of TAZ. In vivo studies using BALB/c nude mice examined the impact of USP43 knockdown on tumor growth and metastasis.

RESULTS

USP43 was overexpressed in CC tissues and cell lines. Silencing of USP43 reduced cell proliferation, migration, invasion, and the epithelial-mesenchymal transition (EMT) process. Co-IP and ubiquitination assays revealed that USP43 interacted with and stabilized TAZ by inhibiting TAZ ubiquitination. CHX chase experiments confirmed that USP43 prolonged TAZ protein stability. In vivo, USP43 knockdown led to reduced tumor growth and lung metastasis. Overexpression of TAZ reversed the inhibitory effects of USP43 silencing on CC cell proliferation, migration, invasion and EMT CONCLUSION: USP43 promotes CC cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) by activating the Hippo/TAZ pathway. These findings enhance our understanding of USP43's role in CC progression and highlight potential therapeutic targets for the treatment of CC.

Targeting YAP/TAZ-TEAD signaling as a therapeutic approach in head and neck squamous cell carcinoma

Genetic alterations in Hippo pathway and the consequent activation of YAP/TAZ-TEAD are frequently observed in HPV-negative head and neck squamous cell carcinoma (HNSCC) patients. These include loss-of-function mutation and/or copy number loss of FAT1, and amplification of YAP1 and WWTR1 (encoding TAZ), thus raising the possibility that HNSCC cells may be dependent on YAP/TAZ-TEAD-mediated transcriptional programs. In this regard, the recent development of small molecule TEAD inhibitors (smTEADi) provides an opportunity to therapeutically target Hippo pathway dysregulation in human malignancies. This prompted us to explore the potential benefit of pharmacologically targeting the YAP/TAZ-TEAD axis in this disease. Here, we provide the pre-clinical evidence for the antitumor activity of novel smTEADi, SW-682 in HPV-negative HNSCC. By the use of multiple complementary experimental approaches, including siRNA knockdown, expression of a genetically encoded TEAD inhibitor peptide (pTEADi), and SW-682, we revealed that disruption of YAP/TAZ-TEAD interaction suppresses YAP/TAZ-TEAD-dependent target gene transcription and growth of HNSCC tumors. HNSCC cells with genetic alterations in FAT1 were more sensitive to TEADi compared to FAT1-wild type cells. Mechanistically, TEADi suppressed cell cycle progression and promoted the expression of terminal differentiation gene programs, resulting in tumor growth inhibition. A HNSCC-specific TEADi target gene set was defined from RNA-seq data, which is highly expressed in HNSCC tissues and predicts poor prognosis of HPV-negative HNSCC patients. Our results underscore that YAP/TAZ-TEAD-mediated growth-promoting programs represent a vulnerability in HPV-negative HNSCC, thus providing a pre-clinical rationale for the future evaluation of YAP/TAZ-TEAD targeting strategies as a therapeutic approach for HPV-negative HNSCC patients.

TAZ-hTrap: A Rationally Designed, Disulfide-Stapled Tead Helical Hairpin Trap to Selectively Capture Hippo Signaling Taz With Potent Antigynecological Tumor Activity

Transcriptional enhanced associate domain (Tead)-mediated Hippo signaling pathway regulates diverse physiological processes; its dysfunction has been implicated in an increasing number of human gynecological cancers. The transcriptional coactivator with PDZ-binding motif (Taz) binds to and then activates Tead through forming a three-helix bundle (THB) at their complex interface. The THB is defined by a double-helical hairpin from Tead and a single α-helix from Taz, serving as the key interaction hotspot between Tead and Taz. In the present study, the helical hairpin was derived from Tead protein to generate a hairpin segment, which is a 25-mer polypeptide consisting of a longer helical arm-1 and a shorter helical arm-2 as well as a flexible loop linker between them. Dynamics simulation and energetics characterization revealed that the hairpin peptide is intrinsically disordered when splitting from its protein context, thus incurring a large entropy penalty upon binding to Taz α-helix. A disulfide bridge was introduced across the two helical arms of hairpin peptide to obtain a strong binder termed TAZ-hTrap, which can maintain in a considerably structured, native-like conformation in unbound state, and the entropy penalty was minimized by disulfide stapling to effectively improve its affinity toward the α-helix. These computational findings can be further substantiated by circular dichroism and fluorescence polarization at molecular level, and viability assay also observed a potent cytotoxic effect on diverse human gynecological tumors at cellular level. In addition, we further demonstrated that the TAZ-hTrap has a good selectivity for its cognate Taz over other noncognate proteins that share a high conservation with the Taz α-helix.

The Role of Yes-Associated Protein in Inflammatory Diseases and Cancer

Yes-associated protein (YAP) plays a central role in the Hippo pathway, primarily governing cell proliferation, differentiation, and apoptosis. Its significance extends to tumorigenesis and inflammatory conditions, impacting disease initiation and progression. Given the increasing relevance of YAP in inflammatory disorders and cancer, this study aims to elucidate its pathological regulatory functions in these contexts. Specifically, we aim to investigate the involvement and molecular mechanisms of YAP in various inflammatory diseases and cancers. We particularly focus on how YAP activation, whether through Hippo-dependent or independent pathways, triggers the release of inflammation and inflammatory mediators in respiratory, cardiovascular, and digestive inflammatory conditions. In cancer, YAP not only promotes tumor cell proliferation and differentiation but also modulates the tumor immune microenvironment, thereby fostering tumor metastasis and progression. Additionally, we provide an overview of current YAP-targeted therapies. By emphasizing YAP's role in inflammatory diseases and cancer, this study aims to enhance our understanding of the protein's pivotal involvement in disease processes, elucidate the intricate pathological mechanisms of related diseases, and contribute to future drug development strategies targeting YAP.

Ultraviolet B Exposure Does Not Influence the Expression of YAP mRNA in Human Epidermal Keratinocytes-Preliminary Study

Background: The causal relationship between exposure to ultraviolet radiation and the development of skin cancers requires constant research for possible orchestrating mechanisms. In recent years, the Hippo pathway, along with its effector protein YAP, became implicated in cutaneous carcinogenesis; however, Hippo pathway regulation by ultraviolet radiation has not been described thoroughly. In order to address this issue, we focused on how different doses of ultraviolet B affect Hippo signaling pathway components and its upstream regulators, JNK1/2 and ABL1, in human keratinocytes. Additionally, we decided to determine how silencing of YAP influences Hippo pathway component expression. Methods: Primary epidermal keratinocytes were irradiated using UVB lamps with increasing doses of ultraviolet B radiation (including 311 nm UVB). Real-time PCR was used to determine the mRNA levels of each investigated gene. The experiment was then performed after YAP silencing using siRNA transfection. Additionally, we determined the mRNA expression of Hippo pathway components in an A431 cSCC cell line. Results: We observed that YAP mRNA expression in the A431 cell line was insignificant in comparison to control, while in the case of LATS1/2, a significant increase was noted. UVB irradiation did not change the levels of YAP mRNA expression in human epidermal keratinocytes. LATS1, LATS2, ABL1 and MAP4K4 mRNA expression was significantly upregulated after UVB irradiation in non-YAP-silenced keratinocytes in a dose-dependent manner, while after YAP silencing, only LATS2 and ABL1 showed significant mRNA upregulation. The 311 nm UVB irradiation resulted in significant, dose-dependent mRNA upregulation in non-YAP-silenced keratinocytes for LATS1, ABL1 and MAP4K4. After YAP silencing, a significant change in mRNA expression was present only in the case of ABL1. Conclusions: YAP mRNA expression does not significantly increase after exposure to UVB; however, it upregulates the expression of its proven (LATS1/2, JNK1/2) regulators, suggesting that in real-life settings, UV-induced dysregulation of the Hippo pathway may not be limited to YAP.

The role of C1orf50 in breast cancer progression and prognosis

Although the prognosis of breast cancer has significantly improved compared to other types of cancer, there are still some patients who expire due to recurrence or metastasis. Therefore, it is necessary to develop a method to identify patients with poor prognosis at the early stages of cancer. In the process of discovering new prognostic markers from genes of unknown function, we found that the expression of C1orf50 determines the prognosis of breast cancer patients, especially for those with Luminal A breast cancer. This study aims to elucidate the molecular role of C1orf50 in breast cancer progression. Bioinformatic analyses of the breast cancer dataset of TCGA, and in vitro analyses, reveal the molecular pathways influenced by C1orf50 expression. C1orf50 knockdown suppressed the cell cycle of breast cancer cells and weakened their ability to maintain the undifferentiated state and self-renewal capacity. Interestingly, upregulation of C1orf50 increased sensitivity to CDK4/6 inhibition. In addition, C1orf50 was found to be more abundant in breast cancer cells than in normal breast epithelium, suggesting C1orf50's involvement in breast cancer pathogenesis. Furthermore, the mRNA expression level of C1orf50 was positively correlated with the expression of PD-L1 and its related factors. These results suggest that C1orf50 promotes breast cancer progression through cell cycle upregulation, maintenance of cancer stemness, and immune evasion mechanisms. Our study uncovers the biological functions of C1orf50 in Luminal breast cancer progression, a finding not previously reported in any type of cancer.

LATS1/2 inactivation in the mammary epithelium drives the evolution of a tumor-associated niche

Basal-like breast cancers exhibit distinct cellular heterogeneity that contributes to disease pathology. In this study we used a genetic mouse model of basal-like breast cancer driven by epithelial-specific inactivation of the Hippo pathway-regulating LATS1 and LATS2 kinases to elucidate epithelial-stromal interactions. We demonstrate that basal-like carcinoma initiation in this model is accompanied by the accumulation of distinct cancer-associated fibroblasts and macrophages and dramatic extracellular matrix remodeling, phenocopying the stromal diversity observed in human triple-negative breast tumors. Dysregulated epithelial-stromal signals were observed, including those mediated by TGF-β, PDGF, and CSF. Autonomous activation of the transcriptional effector TAZ was observed in LATS1/2-deleted cells along with non-autonomous activation within the evolving tumor niche. We further show that inhibition of the YAP/TAZ-associated TEAD family of transcription factors blocks the development of the carcinomas and associated microenvironment. These observations demonstrate that carcinomas resulting from Hippo pathway dysregulation in the mammary epithelium are sufficient to drive cellular events that promote a basal-like tumor-associated niche and suggest that targeting dysregulated YAP/TAZ-TEAD activity may offer a therapeutic opportunity for basal-like mammary tumors.

The IGF2BP1 oncogene is a druggable m6A-dependent enhancer of YAP1-driven gene expression in ovarian cancer

The Hippo/YAP1 signaling pathway regulates normal development by controlling contact inhibition of growth. In cancer, YAP1 activation is often dysregulated, leading to excessive tumor growth and metastasis. SRC kinase can cross talk to Hippo signaling by disrupting adherens junctions, repressing the Hippo cascade, or activating YAP1 to promote proliferation. Here, we demonstrate that the IGF2 messenger RNA-binding protein 1 (IGF2BP1) impedes the repression of YAP1 by Hippo signaling in carcinomas. IGF2BP1 stabilizes the YAP1 messenger RNA (mRNA) and enhances YAP1 protein synthesis through an m6A-dependent interaction with the 3' untranslated region of the YAP1 mRNA, thereby increasing YAP1/TAZ-driven transcription to bypass contact inhibition of tumor cell growth. Inhibiting IGF2BP1-mRNA binding using BTYNB reduces YAP1 levels and transcriptional activity, leading to significant growth inhibition in carcinoma cells and ovarian cancer organoids. In contrast, SRC inhibition with Saracatinib fails to inhibit YAP1/TAZ-driven transcription and cell growth in general. This is particularly significant in de-differentiated, rather mesenchymal carcinoma-derived cells, which exhibit high IGF2BP1 and YAP1 expression, rendering them less reliant on SRC-directed growth stimulation. In such invasive carcinoma models, the combined inhibition of SRC, IGF2BP1, and YAP1/TAZ proved superior over monotherapies. These findings highlight the therapeutic potential of targeting IGF2BP1, a key regulator of oncogenic transcription networks.

Prognostic and Immunotherapeutic Predictive Value of CAD Gene in Hepatocellular Carcinoma: Integrated Bioinformatics and Experimental Analysis

Hepatocellular carcinoma (HCC) is a common type of cancer that ranks first in cancer-associated death worldwide. Carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase (CAD) are the key components of the pyrimidine pathway, which promotes cancer development. However, the function of CAD in HCC needs to be clarified. In this study, the clinical and transcriptome data of 424 TCGA-derived HCC cases were analyzed. The results demonstrated that high CAD expression was associated with poor prognosis in HCC patients. The effect of CAD on HCC was then investigated comprehensively using GO annotation analysis, KEGG enrichment analysis, Gene Set Enrichment Analysis (GSEA), and CIBERSORT algorithm. The results showed that CAD expression was correlated with immune checkpoint inhibitors and immune cell infiltration. In addition, low CAD levels in HCC patients predicted increased sensitivity to anti-CTLA4 and PD1, while HCC patients with high CAD expression exhibited high sensitivity to chemotherapeutic and molecular-targeted agents, including gemcitabine, paclitaxel, and sorafenib. Finally, the results from clinical sample suggested that CAD expression increased remarkably in HCC compared with non-cancerous tissues. Loss of function experiments demonstrated that CAD knockdown could significantly inhibit HCC cell growth and migration both in vitro and in vivo. Collectively, the results indicated that CAD is a potential oncogene during HCC metastasis and progression. Therefore, CAD is recommended as a candidate marker and target for HCC prediction and treatment.

Overexpression of YAP confers radioresistance to esophageal cancer by altering the tumor microenvironment

This study aimed to investigate the role of yes-associated protein (YAP) in the radiotherapy sensitivity of esophageal squamous cell carcinoma (ESCC). The clonogenic ability of ESCC cells was reduced after YAP silencing and radiotherapy. Overexpression of YAP promoted cell survival and had a synergistic effect with the hypoxic microenvironment. YAP was found to directly regulate hypoxia-inducible factor 1α (HIF-1α). Bioinformatics analysis revealed the involvement of YAP in modulating the tumor immune microenvironment. Inhibition of YAP expression reduced myeloid-derived suppressor cells (MDSCs) and influenced the immunosuppressive state, leading to radio resistance. These findings provide insights into the YAP-HIF-1α interaction and support YAP as a potential target for enhancing radiotherapy sensitivity in esophageal cancer.

Decoding chromosomal instability insights in CRC by integrating omics and patient-derived organoids

BACKGROUND

Chromosomal instability (CIN) is involved in about 70% of colorectal cancers (CRCs) and is associated with poor prognosis and drug resistance. From a clinical perspective, a better knowledge of these tumour's biology will help to guide therapeutic strategies more effectively.

METHODS

We used high-density chromosomal microarray analysis to evaluate CIN level of patient-derived organoids (PDOs) and their original mCRC tissues. We integrated the RNA-seq and mass spectrometry-based proteomics data from PDOs in a functional interaction network to identify the significantly dysregulated processes in CIN. This was followed by a proteome-wGII Pearson correlation analysis and an in silico validation of main findings using functional genomic databases and patient-tissues datasets to prioritize the high-confidence CIN features.

RESULTS

By applying the weighted Genome Instability Index (wGII) to identify CIN, we classified PDOs and demonstrated a good correlation with tissues. Multi-omics analysis showed that our organoids recapitulated genomic, transcriptomic and proteomic CIN features of independent tissues cohorts. Thanks to proteotranscriptomics, we uncovered significant associations between mitochondrial metabolism and epithelial-mesenchymal transition in CIN CRC PDOs. Correlating PDOs wGII with protein abundance, we identified a subset of proteins significantly correlated with CIN. Co-localisation analysis in PDOs strengthened the putative role of IPO7 and YAP, and, through in silico analysis, we found that some of the targets give significant dependencies in cell lines with CIN compatible status.

CONCLUSIONS

We first demonstrated that PDO models are a faithful reflection of CIN tissues at the genetic and phenotypic level. Our new findings prioritize a subset of genes and molecular processes putatively required to cope with the burden on cellular fitness imposed by CIN and associated with disease aggressiveness.