Cordycepin alleviates hepatic fibrosis in association with the inhibition of glutaminolysis to promote hepatic stellate cell senescence.

Cordycepin (CRD) is an active component derived from Cordyceps militaris, which possesses multiple biological activities and uses in liver disease. However, whether CRD improves liver fibrosis by regulating hepatic stellate cell (HSC) activation has remained unknown. The study aims further to clarify the activities of CRD on liver fibrosis and elucidate the possible mechanism. Our results demonstrated that CRD significantly relieved hepatocyte injury and inhibited HSC activation, alleviating hepatic fibrogenesis in the Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC)-induced mice model. In vitro, CRD exhibited dose-dependent repress effects on HSC proliferation, migration, and pro-fibrotic function in TGF-ß1-activated LX-2 and JS-1 cells. The functional enrichment analysis of RNA-seq data indicated that the pathway through which CRD alleviates HSC activation involves cellular senescence and cell cycle-related pathways. Furthermore, it was observed that CRD accumulated the number of senescence-associated a-galactosidase positive cells and the levels of senescencemarker p21, and provoked S phasearrestof activated HSC. Remarkably, CRD treatment abolished TGF-ß-induced yes-associated protein (YAP) nuclear translocation that acts upstream of glutaminolysis in activated HSC. On the whole, CRD significantly inhibited glutaminolysis of activated-HSC and induced cell senescence through the YAP signaling pathway, consequently alleviating liver fibrosis, which may be a valuable supplement for treating liver fibrosis.

The Ethyl acetate extract from Celastrus orbiculatus suppresses non-small-cell lung cancer by activating Hippo signaling and inhibiting YAP nuclear translocation.

BACKGROUND: Celastrus orbiculatus Thunb. is a medicinal plant that has been widely used for thousands of years in China, and the ethyl acetate extract (Celastrus orbiculatus Thunb. Extract, COE) from its stem was reported to exert antitumor and anti-inflammatory effects in various preclinical studies. However, the anti-non-small-cell lung cancer activity of COE and its potential mechanism are not yet fully understood. PURPOSE: To investigate the antitumor effects of COE on non-small-cell lung cancer (NSCLC) cells and explore its molecular mechanism from the perspective of Hippo signaling, YAP nuclear translocation, and reactive oxygen species (ROS) generation. METHODS: The effects of COE on proliferation, cell cycle arrest, apoptosis, stemness, and senescence in NSCLC cell lines were determined by CCK-8, clone formation, flow cytometry, and ß-galactosidase staining assays. The effects of COE on Hippo signaling were investigated by Western blotting. The intracellular expression and distribution of YAP were analyzed by immunofluorescence assay. DCFH-DA probe combined with flow cytometry was used to detect intracellular total ROS levels in NSCLC cells after COE treatment. Xenograft tumor model was established, and the animal living image system was employed to analyze the effects of COE on the Hippo-YAP signaling in vivo. RESULT: COE significantly inhibited NSCLC activity in vitro and in vivo, mainly by proliferation inhibition, cycle arrest, apoptosis promotion, senescence promotion, and stemness downregulation. COE strongly activated Hippo signaling and inhibited YAP expression and nuclear retention. Activation of Hippo signaling induced by COE was associated with ROS-mediated phosphorylation of MOB1. CONCLUSION: This study demonstrated that COE inhibited NSCLC through activating Hippo signaling and suppressing YAP nuclear translocation, in which ROS may play a role in the phosphorylation of the MOB1 protein.

Transmembrane protein KIRREL1 regulates Hippo signaling via a feedback loop and represents a therapeutic target in YAP/TAZ-active cancers.

The Hippo tumor-suppressor pathway is frequently dysregulated in human cancers and represents a therapeutic target. However, strategies targeting the mammalian Hippo pathway are limited because of the lack of a well-established cell-surface regulator. Here, we show that transmembrane protein KIRREL1, by interacting with both SAV1 and LATS1/2, promotes LATS1/2 activation by MST1/2 (Hippo kinases), and LATS1/2 activation, in turn, inhibits activity of YAP/TAZ oncoproteins. Conversely, YAP/TAZ directly induce the expression of KIRREL1 in a TEAD1-4-dependent manner. Indeed, KIRREL1 expression positively correlates with canonical YAP/TAZ target gene expression in clinical tumor specimens and predicts poor prognosis. Moreover, transgenic expression of KIRREL1 effectively blocks tumorigenesis in a mouse intrahepatic cholangiocarcinoma model, indicating a tumor-suppressor role of KIRREL1. Hence, KIRREL1 constitutes a negative feedback mechanism regulating the Hippo pathway and serves as a cell-surface marker and potential drug target in cancers with YAP/TAZ dependency.

Discovering inhibitors of TEAD palmitate binding pocket through virtual screening and molecular dynamics simulation.

Transcriptional enhanced associate domain (TEAD) proteins bind to YAP/TAZ and mediate YAP/TAZ-induced gene expression. TEADs are not only the key transcription factors and final effector of the Hippo signaling pathway, but also the proteins that regulate cell proliferation and apoptosis. Disorders of Hippo signaling pathway occur in liver cancer, breast cancer, colon cancer and other cancers. S-palmitylation can stabilize the structure of TEADs and is also a necessary condition for the binding of TEADs to YAP/TAZ. The absence of TEAD palmitoylation prevents TEADs from binding to chromatin, thereby inhibiting the transcription and expression of downstream target genes in the Hippo pathway through a dominant-negative mechanism. Therefore, disrupting the S-palmitylation of TEADs has become an attractive and very feasible method in cancer treatment. The palmitate binding pockets of TEADs are conservative, and the crystal structures of TEAD2-palmitoylation inhibitor complexes and the potential TEAD2 inhibitors are more than other TEADs, TEAD2 can be selected to be the target receptor. In this study, structure-based and ligand-based virtual screening, molecular dynamics simulations, Molecular Mechanics Poisson-Boltzmann Surface Area (MM/PBSA) calculations, residue decomposition binding energy calculations, and ADME predictions have been performed to discover 11 potential TEAD2 S-palmitylation inhibitors. ChEBML196567 and ZINC000013942794 are the most recommended, because they formed strong binding energies and stable hydrogen bonds with TEAD2 and have good drugbility and high human oral absorption. We found that it was easier to find the targeting small molecules using a combination of structure-based and ligand-based virtual screening methods. Besides, a new core structure has been found in the selected small molecules. In addition, we analyzed the binding modes of these small molecules to TEAD2, and confirmed the hot spot residues Cys380, Ser345, Tyr426, Phe428, Ile408, and Met379. AVAILABILITY OF DATA AND MATERIAL: Supplementary materials are available online.

Transcriptional repression of estrogen receptor alpha by YAP reveals the Hippo pathway as therapeutic target for ER+ breast cancer.

Extensive knowledge has been gained on the transcription network controlled by ERα, however, the mechanism underlying ESR1 (encoding ERα) expression is less understood. We recently discovered that the Hippo pathway is required for the proper expression of ESR1. YAP/TAZ are transcription coactivators that are phosphorylated and inhibited by the Hippo pathway kinase LATS. Here we delineated the molecular mechanisms underlying ESR1 transcription repression by the Hippo pathway. Mechanistically, YAP binds to TEAD to increase local chromatin accessibility to stimulate transcription of nearby genes. Among the YAP target genes, Vestigial-Like Protein 3 (VGLL3) competes with YAP/TAZ for binding to TEAD transcription factor and recruits the NCOR2/SMRT repressor to the super-enhancer of ESR1 gene, leading to epigenetic alteration and transcriptional silencing. We developed a potent LATS inhibitor VT02956. Targeting the Hippo pathway by VT02956 represses ESR1 expression and inhibits the growth of ER+ breast cancer cells as well as patient-derived tumour organoids. Moreover, histone deacetylase inhibitors, such as Entinostat, induce VGLL3 expression to inhibit ER+ breast cancer cells. Our study suggests LATS as unexpected cancer therapeutic targets, especially for endocrine-resistant breast cancers.

Trehangelins ameliorate inflammation-induced skin senescence by suppressing the epidermal YAP-CCN1 axis.

Trehangelins (THG) are newly identified trehalose compounds derived from broth cultures of an endophytic actinomycete, Polymorphospora rubra. THG are known to suppress Cellular Communication Network factor 1 (CCN1), which regulates collagen homeostasis in the dermis. Although the physical properties of THG suggest a high penetration of the stratum corneum, the effect of THG on the epidermis has not been reported. Here we describe a possible mechanism involved in skin aging focusing on the effect of THG on epidermal CCN1. This study shows that: (1) THG suppress epidermal CCN1 expression by inhibiting the translocation of Yes-Associated Protein (YAP) to nuclei. (2) Epidermal CCN1, localized at the basement membrane, regulates the balance between the growth and differentiation of keratinocytes. (3) Keratinocytes secrete more CCN1 than fibroblasts, which leads to disruption of the basement membrane and extracellular matrix components. (4) The secretion of CCN1 from keratinocytes is increased by ultraviolet B exposure, especially in aged keratinocytes, and deteriorates the elastic fiber structures in the underlying dermis. (5) Topical application of THG ameliorates the structure of the basement membrane in ex vivo human skin explants. Taken together, THG might be a promising treatment for aged skin by suppressing the aberrant YAP-CCN1 axis.

An innovative targeted therapy for fluoroscopy-induced chronic radiation dermatitis.

Fluoroscopy-induced chronic radiation dermatitis (FICRD) is a complication of fluoroscopy-guided intervention. Unlike acute radiation dermatitis, FICRD is different as delayed onset and usually appears without preexisting acute dermatitis. Unfortunately, the chronic and progressive pathology of FICRD makes it difficult to treat, and some patients need to receive wide excision and reconstruction surgery. Due to lack of standard treatment, investigating underlying mechanism is needed in order to develop an effective therapy. Herein, the Hippo pathway is specifically identified using an RNA-seq analysis in mild damaged skin specimens of patients with FICRD. Furthermore, specific increase of the Yes-associated protein (YAP1), an effector of the Hippo pathway, in skin region with mild damage plays a protective role for keratinocytes via positively regulating the numerous downstream genes involved in different biological processes. Interestingly, irradiated-keratinocytes inhibit activation of fibroblasts under TGF-ß1 treatment via remote control by an exosome containing YAP1. More importantly, targeting one of YAP1 downstream genes, nuclear receptor subfamily 3 group C member 1 (NR3C1), which encodes glucocorticoid receptor, has revealed its therapeutic potential to treat FICRD by inhibiting fibroblasts activation in vitro and preventing formation of radiation ulcers in a mouse model and in patients with FICRD. Taken together, this translational research demonstrates the critical role of YAP1 in FICRD and identification of a feasible, effective therapy for patients with FICRD. KEY MESSAGES: • YAP1 overexpression in skin specimens of radiation dermatitis from FICRD patient. • Radiation-induced YAP1 expression plays protective roles by promoting DNA damage repair and inhibiting fibrosis via remote control of exosomal YAP1. • YAP1 positively regulates NR3C1 which encodes glucocorticoid receptor expression. • Targeting glucocorticoid receptor by prednisolone has therapeutic potential for FICRD patient.

Traditional Chinese medicine Yiqi Huoxue recipe attenuates hepatic fibrosis via YAP/TAZ signaling.

BACKGROUND/AIMS: The Yiqi Huoxue (YQHX) recipe has been shown to attenuate liver fibrosis, but precise mechanisms have not yet been elucidated. Recently, Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) signaling has been implicated in liver fibrogenesis. This study investigated whether the YAP/TAZ signaling is involved in the therapeutic effect of YQHX on hepatic fibrosis. MATERIALS AND METHODS: Wistar rats were used to generate a model of carbon tetrachloride (CCl4)-induced liver fibrosis. Chronic hepatitis B (CHB) patients with liver fibrosis were enrolled and assigned to receive either nucleoside/nucleotide analogues (NAs) or NAs plus YQHX. Histology, immunohistochemistry, qRT-PCR, and western blotting were conducted to mechanistically assess the therapeutic effects of YQHX on liver fibrosis. RESULTS: YQHX markedly alleviated morphological alterations in CCl4-induced liver fibrosis and decreased markers of hepatic fibrosis in rats. Furthermore, YQHX significantly suppressed CCl4-meidated activation of the transforming growth factor-beta (TGF-ß)/Smad signaling pathway. Notably, CCl4 induced up-regulation of YAP, TAZ, and connective tissue growth factor (CTGF), which were significantly abrogated by YQHX. Consistent with the above major findings in rats, CHB patients treated with NAs plus YQHX had greater improvement in liver fibrosis than those given NAs alone (71.4% vs. 28.6%; P = 0.057). In addition, hepatic and plasma levels of YAP were significantly decreased after YQHX treatment in CHB patients with liver fibrosis. CONCLUSION: YAP/TAZ signaling plays a role, at least in part, in the anti-fibrotic activity of YQHX. The findings may help to better understand the mechanisms of YQHX in the treatment of liver fibrosis.

The novel FAT4 activator jujuboside A suppresses NSCLC tumorigenesis by activating HIPPO signaling and inhibiting YAP nuclear translocation.

FAT atypical cadherin 4 (FAT4) has been identified as a tumor suppressor in lung cancers. However, no agent for lung cancer treatment targeting FAT4 has been used in the clinic. Jujuboside A (JUA) is a major active compound in Semen Ziziphi Spinosae. Semen Ziziphi Spinosae is a traditional Chinese herbal medicine used clinically for tumor treatment to improve patients' quality of life. However, the anti-lung cancer activity and the underlying mechanisms of JUA are not yet fully understood. Here, we demonstrated the anti-lung cancer activity of JUA in two lung cancer mice models and three non-small cell lung cancer (NSCLC) cell lines, and further illustrated its underlying mechanisms. JUA suppressed the occurrence and development of lung cancer and extended mice survival in vivo, and suppressed NSCLC cell activities through cell cycle arrest, proliferation suppression, stemness inhibition and senescence promotion. Moreover, JUA directly bound with and activated FAT4, subsequently activating FAT4-HIPPO signaling and inhibiting YAP nuclear translocation. Knockdown of FAT4 diminished JUA's effects on HIPPO signaling, YAP nuclear translocation, cell proliferation and cellular senescence. In conclusion, JUA significantly suppressed NSCLC tumorigenesis by regulating FAT4-HIPPO-YAP signaling. Our findings suggest that JUA is a novel FAT4 activator that can be developed as a promising NSCLC therapeutic agent targeting the FAT4-HIPPO-YAP pathway.