Semisynthesis and biological evaluation of novel honokiol thioethers against colon cancer cells HCT116 via inhibiting the transcription and expression of YAP protein.

Honokiol, derived from Magnolia officinalis (a traditional Chinese medicine), has been reported to have anticancer activity. Here, a series of novel honokiol thioethers bearing a 1,3,4-oxadiazole moiety were prepared and evaluated for their anticancer activities against three types of digestive system tumor cells. Biological evaluation showed that honokiol derivative 3k exhibited the best antiproliferative activity against HCT116 cells with an IC50 value of 6.1 µmol/L, superior to the reference drug 5-fluorouracil (IC50: 9.63 ± 0.27 µmol/L). The structure-activity relationships (SARs) indicated that the introduction of -(4-NO2)Ph, 3-pyridyl, -(2-F)Ph, -(4-F)Ph, -(3-F)Ph, -(4-Cl)Ph, and -(3-Cl)Ph groups was favorable for enhancing the anticancer activity of the title honokiol thioethers. Further study revealed that honokiol thioether 3k can well inhibit the proliferation of colon cancer cells HCT116, arresting the cells in G1 phase and inducing cell death. Moreover, a preliminary mechanism study indicated that 3k directly inhibits the transcription and expression of YAP protein without activating the Hippo signaling pathway. Thus, honokiol thioether 3k could be deeply developed for the development of honokiol-based anticancer candidates.

gp130 Controls Cardiomyocyte Proliferation and Heart Regeneration.

BACKGROUND: A key cause of the high mortality of cardiovascular diseases is the cardiomyocyte inability to renew after cardiac injury. As a promising strategy to supplement functional myocytes for cardiac repair, there is a pressing need to understand the cellular and molecular mechanisms of heart regeneration. METHODS: Seven genetic mouse lines were used: global OSM (oncostatin M) knockout, monocyte-/macrophage-specific OSM deletion, cardiomyocyte-specific lines, including OSM receptor deletion, gp130 (glycoprotein 130) deletion, gp130 activation, and Yap (yes-associated protein) ablation with gp130 activation mice. A series of molecular signaling experiments, including RNA sequencing, immunostaining, coimmunoprecipitation, and imaging flow cytometry, were conducted. Two models of cardiac injury, apical resection and myocardial infarction operation, were performed in neonatal, juvenile, and adult mice. Heart regeneration and cardiac function were evaluated by Masson staining and echocardiography, respectively. Gene recombinant adenovirus-associated virus was constructed and infected myocardial-infarcted mice as a gene therapy. RESULTS: OSM was identified by RNA sequencing as a key upstream regulator of cardiomyocyte proliferation during neonatal heart regeneration in mice. Cardiomyocyte proliferation and heart regeneration were suspended in neonatal mice after cardiac injury when OSM was conditionally knockout in macrophages. The cardiomyocyte-specific deficiency of the OSM receptor heterodimers, OSM receptor and gp130, individually in cardiomyocytes reduced myocyte proliferation and neonatal heart regeneration. Conditional activation of gp130 in cardiomyocytes promoted cardiomyocyte proliferation and heart regeneration in juvenile and adult mice. Using RNA sequencing and functional screening, we found that Src mediated gp130-triggered cardiomyocyte proliferation by activating Yap (yes-associated protein) with Y357 phosphorylation independently of the Hippo pathway. Cardiomyocyte-specific deletion of Yap in Myh6-gp130ACT mice blocked the effect of gp130 activation-induced heart regeneration in juvenile mice. Gene therapy with adenovirus-associated virus encoding constitutively activated gp130 promoted cardiomyocyte proliferation and heart regeneration in adult mice after myocardial infarction. CONCLUSIONS: Macrophage recruitment is essential for heart regeneration through the secretion of OSM, which promotes cardiomyocyte proliferation. As the coreceptor of OSM, gp130 activation is sufficient to promote cardiomyocyte proliferation by activating Yap through Src during heart regeneration. gp130 is a potential therapeutic target to improve heart regeneration after cardiac injury.

Alpha-catenins control cardiomyocyte proliferation by regulating Yap activity.

RATIONALE: Shortly after birth, muscle cells of the mammalian heart lose their ability to divide. Thus, they are unable to effectively replace dying cells in the injured heart. The recent discovery that the transcriptional coactivator Yes-associated protein (Yap) is necessary and sufficient for cardiomyocyte proliferation has gained considerable attention. However, the upstream regulators and signaling pathways that control Yap activity in the heart are poorly understood. OBJECTIVE: To investigate the role of α-catenins in the heart using cardiac-specific αE- and αT-catenin double knockout mice. METHODS AND RESULTS: We used 2 cardiac-specific Cre transgenes to delete both αE-catenin (Ctnna1) and αT-catenin (Ctnna3) genes either in the perinatal or in the adult heart. Perinatal depletion of α-catenins increased cardiomyocyte number in the postnatal heart. Increased nuclear Yap and the cell cycle regulator cyclin D1 accompanied cardiomyocyte proliferation in the α-catenin double knockout hearts. Fetal genes were increased in the α-catenin double knockout hearts indicating a less mature cardiac gene expression profile. Knockdown of α-catenins in neonatal rat cardiomyocytes also resulted in increased proliferation, which could be blocked by knockdown of Yap. Finally, inactivation of α-catenins in the adult heart using an inducible Cre led to increased nuclear Yap and cardiomyocyte proliferation and improved contractility after myocardial infarction. CONCLUSIONS: These studies demonstrate that α-catenins are critical regulators of Yap, a transcriptional coactivator essential for cardiomyocyte proliferation. Furthermore, we provide proof of concept that inhibiting α-catenins might be a useful strategy to promote myocardial regeneration after injury.

α-Hederin Inhibits the Proliferation of Hepatocellular Carcinoma Cells via Hippo-Yes-Associated Protein Signaling Pathway.

Aims: Yes-associated protein (YAP), a downstream protein in the Hippo signaling pathway, plays an important role in tumor proliferation, including in hepatocellular carcinoma (HCC). α-hederin, a monodesmosidic triterpenoid saponin isolated from Fructus akebiae, displayed anti-cancer effects on several cancer cell lines but the precise mechanism has not been ascertained. In the present study, we explored the effects of α-hederin on cell proliferation and apoptosis in human HCC cell lines and the underlying mechanisms. Main Method: Cell proliferation and apoptosis were assessed using 5-ethynyl-2'-deoxyuridine staining, colony formation, flow cytometry. The expression patterns of components of Hippo signaling pathway and apoptotic genes were further examined via RT-qPCR and immunoblotting. A xenograft tumor model in nude mice was used to evaluate the anti-HCC effects of α-hederin in vivo. Results: α-hederin promoted the apoptosis and inhibited the proliferation of SMMC-7721 and HepG2 cells in vitro, and remarkably inhibited the tumor size and weight in the xenograft mouse model. Additionally, α-hederin increased the expression of pro-apoptosis proteins and suppressed the expression of anti-apoptosis proteins. Moreover, α-hederin treatment upregulated the expression of Hippo signaling pathway-related proteins and genes, while, effectively reduced the level of nuclear YAP, which resulted in the inhibition of proliferation and the induction of apoptosis of HCC cells. Finally, the effects of α-hederin on HCC cell proliferation and apoptosis were alleviated by XMU-MP-1, a Mst1/2 inhibitor in vitro. Significance: We identified α-hederin is a novel agonist of Hippo signaling pathway and possesses an anti-HCC efficacy through inhibiting YAP activity.

Hippo-YAP pathway is involved in the effect of NaAsO / 中国药理学通报

Aim To explore the effects of NaAsO

Overexpression of PIK3CA in head and neck squamous cell carcinoma is associated with poor outcome and activation of the YAP pathway.

OBJECTIVES: Phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) is commonly altered in many human tumors, leading to the activation of p110α enzymatic activity that stimulates growth factor-independent cell growth. PIK3CA alterations such as mutation, gene amplification and overexpression are common in head and neck squamous cell carcinoma (HNSCC) and. We aim to explore how these alterations and clinical outcome are associated, as well as the molecular mechanisms involved. MATERIAL AND METHODS: Mutation and copy-number variation in PIK3CA, and whole-genome expression profiles, were analyzed in primary HNSCC tumors from The Cancer Genome Atlas (TCGA) cohort (n = 243). The results were validated in an independent cohort form the University Hospital of A Coruña (UHAC, n = 62). Expression of the PIK3CA gene protein product (PI3K p110α) and nuclear YAP were assessed in tissue microarrays in a cohort from the University Hospital 12 de Octubre (UH12O, n = 91). RESULTS: Only high expression of the PIK3CA gene was associated with poor clinical outcome. The study of gene expression, transcription factor and protein signatures suggested that the activation of the Hippo-YAP pathway, involved in organ size, stem cell maintenance and tumorigenesis, could underlie tumor progression in PI3KCA overexpressing tumors. Tissue arrays showed that PI3K p110α levels correlated with YAP nuclear localization in HNSCC tumors. CONCLUSIONS: High expression of PIK3CA in HNSCC primary tumors identifies patients at high risk for recurrence. In these tumors, progression could rely on the Hippo-YAP pathway instead of the canonical Akt/mTOR pathway. This observation could have important implications in the therapeutic options for patients.

YAP induces cisplatin resistance through activation of autophagy in human ovarian carcinoma cells.

OBJECTIVE: To identify the role of YAP in cisplatin resistance in human ovarian cancer cells and in the regulation of autophagy in these cancer cells. MATERIALS AND METHODS: The cisplatin-sensitive OV2008 parental cell line and its cisplatin-resistant variant C13K were cultured. RNA interference was used to knock down the YAP gene. Accumulation of GFP-LC3 puncta was performed by fluorescence microscopy. The formation of autophagosomes was observed by transmission electron microscopy. Drug sensitivity was examined using CCK-8 assay, while apoptosis, the level of intracellular rhodamine 123 and lysosomal acidification were analyzed by fluorescence-activated cell sorting. Acid phosphatase activity was measured using an acid phosphatase-assay kit. Real-time polymerase chain reaction, Western blotting, and immunofluorescence detection were used to detect the protein and messenger RNA expression of YAP, YAP target genes, CCND1, cleaved PARP, and caspase 3, Atg-3 and -5, and the LC3B protein. RESULTS: YAP signaling may regulate cisplatin resistance in ovarian cancer cells by augmenting cellular autophagic flux. After knockdown of YAP-sensitized C13K cells to cisplatin by inducing a decrease in autophagy, YAP led to an increase in autophagy via enhancement of autolysosome degradation. CONCLUSION: YAP-mediated autophagy may play a protective role in cisplatin-resistant human ovarian cancer cells. Therefore, YAP-mediated autophagy should be explored as a new target for enhancing the efficacy of cisplatin against ovarian cancer and other types of malignancies.

Hippo signaling pathway and colorectal cancer / 国际肿瘤学杂志

Hippo signaling pathway plays a significant role in the development of colorectal cancer,and acts as an important regulatory pathway which regulates cell proliferation and cell differentiation.Multiple proteins and genes in Hippo signaling pathway,especially the downstream YAP protein,play important roles in the occurrence,metastasis,drug resistance and recurrence of colorectal cancer.YAP and other related genes can be used as targeted markers for predicting drug resistance to colorectal cancer.Hippo signaling pathway gene network can be used as targeted therapy or combination therapy,thus providing new ideas for the treatment of colorectal cancer.

Regulation effect of F-actin on senescence of mesenchymal stem cells and its mechanism / 吉林大学学报(医学版)

Objective: To investigate the regulation effects of fibrous-actin (F-actin) on senescent of the human bone marrow mesenchymal stem cells (hBMSCs), and to elucidate the molecular mechanisms of senescence the of hBMSCs. Methods: The hBMSCs were cultured in vitro and divided into control group (P2 hBMSCs), F-actin inhibitor group (P2 hBMSCs were treated with 2. 5 μmol · L-1 F-actin inhibitor Latrunculin B for 1 h) and Pll hBMSCs group (Pll hBMSCs passaged from P2 hBMSCs continuously). The hBMSCs in various groups were induced by osteogenic, adipogenic and chondrogenic induction mediums and the induction effects were identified by Alizarin red staining, SO staining and oil red O staining. The number of Ki67 positive cells, polymerization and morphology of F-actin and YAP subcellular localization were detected by immunofluorescence staining. SA-β-Gal staining was uesd to detect the SA-β-Gal staining positive cells in the hBMSCs in various groups. Results: The Alizarin red staining, SO staining and oil red O staining results showed that the hBMSCs in various groups had the osteogenic, adipogenic and chondrogenic abilities. The immunofluorescence staining and SA-β-Gal staining results showed that the microfilament bundles in the hBMSCs in control group were more thick, the F-actin length was longer, and the YAP mainly concentrated in the nucleus (YAP was activated in the nucleus). Compared with control group, the number of Ki67 positive cells in Pll hBMSCs group was less and the number of SA-β-Gal positive cells was more; the Factin was shorter and thinner, the YAP mainly concentrated in the cytoplasm, and the high cytoplasmic YAP cells was positive for SA-β-Gal staining; in F-actin inhibitor group, the high cytoplasmic YAP inactivation was found in the hBMSCs and the SA-β-Gal staining positive hBMSCs had more senescent cells. Conclusion: To inhibit the entering of YAP into the nucleus can promote the senescence of hBMSCs and F-actin can affect the senescence of hBMSCs by regulating the YAP activity.

Research progress of relation between Hippo-YAP signaling pathway and tumor / 肿瘤研究与临床

The Hippo-YAP signaling pathway,an important signaling pathway of tumor suppressor,is featured by functions of adjusting the organ size and maintaining the dynamic balance between cell proliferation and apoptosis.Several researches have revealed that the Hippo-YAP signaling pathway can affect cell proliferation and apoptosis so as to participate in the development of tumor.This paper will review the effect and mechanism of Hippo-YAP signaling pathway in tumor.

Effects of Hippo pathway component on tumor recurrence after liver transplantation / 中华消化外科杂志

Objective To investigate the expression of Hippo pathway component in hepatic cancer tissues and investigate its effects on the tumor recurrence after Iiver transplantation.Methods The clinical data of 105 patients with liver cancer who were admitted to the Third Affiliated Hospital of Sun Yat-Sen University from July 2004 to September 2009 were retrospectively analyzed.The samples of liver cancer tissues were collected.The maximum diameter,number of foci,blood vessel involvement,preoperative level of alpha-fetoprotein (AFP),results of postoperative pathological examination were analyzed.All the patients were followed up via out-patient examination,mail and phone call.Patients were followed up once a week within the first month after operation,and once a month within the 6 months after operation,and then once every 3 months at 1 year later.The follow-up ended in December 2012 or tumor recurrence.The disease-free survival time began at the date of operation and ended at the time of tumor recurrence.The expressions of Yes-associated protein (YAP),phosphorylated YAP,Hippo pathway component (Lats1/2,pLats1/2,Mst1,pMst1/2) were detected by immunohistochemical staining.All data were analyzed using the chi-square test or Student t test.Factors might influence the postoperative tumorfree survival time after liver transplantation were analyzed using the Cox regression model.The survival curve was drawn by Kaplan-Meier method,and the disease-free survival was analyzed using Log-rank test.Results Positive expressions of YAP and phosphorylated YAP were detected in the nucleus and cytoplasm,and the positive expressions of Lats1/2,pLats1/2,Mst1 and pMst1/2 were detected in the cytoplasm.The positive expressions of YAP,phosphorylated YAP,Latsl/2,pLats1/2,Mst1 and pMst1/2 protein were 51.43％ (54/105),55.24％ (58/105),45.71％ (48/105),9.52％ (10/105),64.76％ (68/105) and 20.00％ (21/105),respectively.The positive expression of YAP was correlated with the tumor diameter,venous infiltration and AJCC stage (x2=4.173,9.611,7.233,P ＜ 0.05).The positive expression of Lats1/2 protein was correlated with tumor diameter and AJCC stages (x2=14.413,7.969,P ＜ 0.05).The positive expression of Mst1 protein was correlated with the tumor diameter (x2=4,129,P ＜0.05).The results of univariate analysis showed that the protein expressions of YAP,Lats1/2,pMst1/2,age,tumor diameter,tissue differentiation,preoperative level of AFP,venous infiltration and AJCC stages were risk factors influencing tumor recurrence after liver transplantation (HR =2.603,0.502,1.802,0.955,3.559,2.395,2.414,2.915,2.086,95％ CI:1.452-4.666,0.287-0.880,1.040-3.123,0.931-0.981,1.921-6.595,1.475-3.889,1.313-4.337,1.604-5.229,1.370-3.176,P ＜ 0.05).The results of multivariate analysis showed that the positive expression of YAP,tumor diameter ＞ 5 cm,low differentiation of tissue and AJCC stages Ⅲ were independent risk factors influencing tumor recurrence after liver transplantation (HR=2.011,2.176,2.390,1.574,95％CI:1.115-3.628,1.125-4.206,1.448-3.945,1.041-2.381,P ＜ 0.05).The median time of follow-up was 13.0 months (range,1.0-96.0 months).Eight patients missed follow-up.Fifty-four patients had tumor recurrence,and the mean time of tumor recurrence was 6.7 months (range,1.0-41.0 months).The disease-free survival time of patients with positive expression of YAP were significantly shorter than those with negative expression of YAP (Log-rank value =12.890,P ＜ 0.05).Conclusions Positive expressions of YAP and phosphorylated YAP were detected in the nucleus and cytoplasm,and the positive expressions of Lats1/2,pLats1/2,Mst1 and pMst1/2 were detected in the cytoplasm.The positive expression of YAP is the independent risk factor for tumor recurrence after liver transplantation.