Mechanism of regulatory effect of recombinant human HMGB1 on endothelial cell angiogenesis / 器官移植

Objective To unravel the possible mechanism of the role of recombinant human high mobility group box 1 (rhHMGB1) protein in regulating the angiogenesis of endothelial cells. Methods Endothelial cells were divided into the control group, bone marrow mesenchymal stem cells (MSC) supernatant group and rhHMGB1 group. The proliferation and survival of endothelial cells were detected by cell counting kit(CCK)-8 assay. The relative expression levels of vascular endothelial growth factor (VEGF), Yes-associated protein (YAP), CD31 and hypoxia inducible factor (HIF)-1α proteins were determined by Western blot. The relative expression levels of VEGF, YAP, CD31 and HIF-1α messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). The migration ability of endothelial cells was assessed by Transwell chamber test. The localization of YAP was detected by immunofluorescence staining. Results Compared with the control group, the migration rate of endothelial cells was increased in the rhHMGB1 group (P < 0.05), and the cell migration rate was enhanced over time. Compared with the control group, the relative expression levels of VEGF and p-YAP proteins were up-regulated in the MSC supernatant group, and the differences were statistically significant (both P < 0.05). Compared with the control group, the relative expression levels of VEGF and HIF-1α proteins, VEGF and CD31 mRNA and YAP and p-YAP proteins were up-regulated, and YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Compared with the MSC supernatant group, the relative expression levels of CD31 mRNA and YAP protein were up-regulated, and the YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Conclusions Exogenous high-concentration rhHMGB1 may promote the migration ability of endothelial cells and up-regulate the expression levels of angiogenesis-related proteins by regulating the recruitment of YAP to the nucleus.

β-catenin ameliorates myocardial infarction by preventing YAP-associated apoptosis

Abstract Objective: To explore whether the effect of β-catenin on MI and MI-induced cardiomyocyte apoptosis is YAP-dependent. Methods: The authors established an MI rat model by ligating the anterior descending branch of the left coronary artery, and an MI cell model by treating cardiomyocytes with H2O2. Results: β-catenin downregulation was observed in MI cardiac tissues and in H2O2-treated cardiomyocytes. Lentiviral-CTNNB1 was administered to MI rats to upregulate β-catenin expression in MI cardiac tissue. β-catenin recovery reduced the myocardial infarct area, fibrosis, and apoptotic cell death in MI rats. H2O2 treatment attenuated cell viability and induced cell death in cardiomyocytes, whereas β-catenin overexpression partially reversed these changes. Moreover, H2O2 treatment caused the deactivation of Yes-Associated Protein (YAP), as detected by increased YAP phosphorylation and reduced the nuclear localization of YAP. Upregulation of β-catenin expression reactivated YAP in H2O2-treated cardiomyocytes. Reactivation of YAP was achieved by administration of Mitochonic Acid-5 (MA-5) to H2O2-treated cardiomyocytes, and deactivation of YAP by CIL56 treatment in β-catenin-overexpressing H2O2-treated cardiomyocytes. MA-5 administration increased cell viability and repressed apoptosis in H2O2-treated cardiomyocytes, whereas CIL56 treatment counteracted the effects of β-catenin overexpression on cell survival and apoptosis. Conclusions: The present data indicate that β-catenin and YAP are effective treatment targets for MI, blocking the apoptotic death of cardiomyocytes.

Effect of Yes-associated protein in regulation of electroacupuncture pretreatment on cerebral ischemia reperfusion injury rats / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) pretreatment on inflammatory reaction, apoptosis and expression of Yes-associated protein (YAP) of ischemic penumbra of cerebral cortex in cerebral ischemia reperfusion injury rats, and to explore the possible mechanism of its neuroprotection effect.@*METHODS@#A total of 84 SD rats were randomized into a sham operation group (12 rats), a model group (18 rats), an EA group (18 rats), an EA+YAP virus transfection group (18 rats) and an EA+virus control group (18 rats). Except for the sham operation group, thread embolization method was adopted to establish the middle cerebral artery occlusion (MCAO) model in rats of the other groups. EA was applied at "Baihui" (GV 20) and "Dazhui" (GV 14) for 30 min in the 3 EA intervention groups 2 h before model establishment, disperse-dense wave, 2 Hz/15 Hz in frequency and 1 mA in intensity. Adenovirus transfection technique was used to induce gene silencing of YAP in the EA+YAP virus transfection group, and adenovirus vectors was injected as negative control in the EA+virus control group 4 d before model establishment. Twenty-four hours after model establishment, neurological function score was evaluated, the relative cerebral infarction area was observed by TTC staining, the apoptosis in the ischemic penumbra of cerebral cortex was detected by TUNEL staining, the levels of inflammatory factors IL-1β, IL-6 and TNF-α in the ischemic penumbra of cerebral cortex was detected by ELISA method, the expression of YAP was detected by Western blot and immunofluorescence.@*RESULTS@#Compared with the sham operation group, the expression of YAP was increased in the model group (@*CONCLUSION@#Electroacupuncture pretreatment can effectively improve the ischemia reperfusion injury, its mechanism may be related to up-regulating the expression of YAP in the ischemic penumbra of cerebral cortex and relieving the apoptosis and inflammatory reaction.

RGFP966 inactivation of the YAP pathway attenuates cardiac dysfunction induced by prolonged hypothermic preservation / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Oxidative stress and apoptosis are the key factors that limit the hypothermic preservation time of donor hearts to within 4–6 h. The aim of this study was to investigate whether the histone deacetylase 3 (HDAC3) inhibitor RGFP966 could protect against cardiac injury induced by prolonged hypothermic preservation. Rat hearts were hypothermically preserved in Celsior solution with or without RGFP966 for 12 h followed by 60 min of reperfusion. Hemodynamic parameters during reperfusion were evaluated. The expression and phosphorylation levels of mammalian STE20-like kinase-1 (Mst1) and Yes-associated protein (YAP) were determined by western blotting. Cell apoptosis was measured by the terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) method. Addition of RGFP966 in Celsior solution significantly inhibited cardiac dysfunction induced by hypothermic preservation. RGFP966 inhibited the hypothermic preservation-induced increase of the phosphorylated (p)-Mst1/Mst1 and p-YAP/YAP ratios, prevented a reduction in total YAP protein expression, and increased the nuclear YAP protein level. Verteporfin (VP), a small molecular inhibitor of YAP-transcriptional enhanced associate domain (TEAD) interaction, partially abolished the protective effect of RGFP966 on cardiac function, and reduced lactate dehydrogenase activity and malondialdehyde content. RGFP966 increased superoxide dismutase, catalase, and glutathione peroxidase gene and protein expression, which was abolished by VP. RGFP966 inhibited hypothermic preservation-induced overexpression of B-cell lymphoma protein 2 (Bcl-2)-associated X (Bax) and cleaved caspase-3, increased Bcl-2 mRNA and protein expression, and reduced cardiomyocyte apoptosis. The antioxidant and anti-apoptotic effects of RGFP966 were cancelled by VP. The results suggest that supplementation of Celsior solution with RGFP966 attenuated prolonged hypothermic preservation-induced cardiac dysfunction. The mechanism may involve inhibition of oxidative stress and apoptosis via inactivation of the YAP pathway.

Long non-coding RNA AGAP2-AS1 affects biological behavior of colon cancer cells through the YAP signaling pathway / 中国肿瘤临床

To investigate the expression of AGAP2-AS1 in colon cancer, its influence on the malignant behavior of colon cancer cells, and its effects on the Yes-associated protein (YAP) signaling pathway. Methods: The expression of AGAP2-AS1 in 457 colon cancer samples and 42 healthy samples was obtained from TCGA. Twenty matched colon cancer and adjacent cancer tissues were collected from patients diagnosed in Yiwu Central Hospital and confirmed by pathology department from January 2018 to March 2019. The expression of AGAP2-AS1 in these tissues, as well as in SW480, HCT-116, and NCM460 cells, was detected by real-time fluorescent quantitative PCR. The changes in cell proliferation, migration and apoptosis were analyzed and detected using a CCK-8 kit, and clone formation, wound-healing assay, and flow cytometry experiments. The levels of YAP, p-YAP, matrix metalloproteinase-2 (MMP2), and MMP9 were evaluated by Western blot. Immunofluorescence was used to examine the localization of YAP in HCT-116 cells. The levels of YAP, p-YAP, MMP2, and MMP9 proteins were evaluated after the co-transfection of pcDNA3.1-AGAP2-AS1 and si-YAP plasmids. Results: TCGA indicated that the expression of AGAP2-AS1 was significantly increased in colon cancer tissues. Similarly, in the present study, AGAP2-AS1 expression was significantly increased in colon cancer tissues and cells. After AGAP2-AS1 knockdown/overexpression, the capacity of migration and proliferation was significantly reduced/increased, and apoptosis was significantly increased/inhibited in colon cancer cells. Moreover, AGAP2-AS1 knockdown triggered the phosphorylation of YAP, and a significant reduction in the expression of MMP2 and MMP9 (P<0.05). Co-transfection studies revealed that AGAP2-AS1 upregulated the expression of MMP2 and MMP9 via activation of the YAP pathway (P<0.05). Conclusions: AGAP2-AS1 was highly expressed in colon cancer tissues and cell lines. AGAP2- AS1 can induce proliferation and migration, and inhibit apoptosis in colon cancer cells. In addition, AGAP2- AS1 regulated MMP2 and MMP9 expression by activating the YAP pathway, thereby affecting colon cancer metastasis.

RGFP966 inactivation of the YAP pathway attenuates cardiac dysfunction induced by prolonged hypothermic preservation / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Oxidative stress and apoptosis are the key factors that limit the hypothermic preservation time of donor hearts to within 4-6 h. The aim of this study was to investigate whether the histone deacetylase 3 (HDAC3) inhibitor RGFP966 could protect against cardiac injury induced by prolonged hypothermic preservation. Rat hearts were hypothermically preserved in Celsior solution with or without RGFP966 for 12 h followed by 60 min of reperfusion. Hemodynamic parameters during reperfusion were evaluated. The expression and phosphorylation levels of mammalian STE20-like kinase-1 (Mst1) and Yes-associated protein (YAP) were determined by western blotting. Cell apoptosis was measured by the terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) method. Addition of RGFP966 in Celsior solution significantly inhibited cardiac dysfunction induced by hypothermic preservation. RGFP966 inhibited the hypothermic preservation-induced increase of the phosphorylated (p)-Mst1/Mst1 and p-YAP/YAP ratios, prevented a reduction in total YAP protein expression, and increased the nuclear YAP protein level. Verteporfin (VP), a small molecular inhibitor of YAP-transcriptional enhanced associate domain (TEAD) interaction, partially abolished the protective effect of RGFP966 on cardiac function, and reduced lactate dehydrogenase activity and malondialdehyde content. RGFP966 increased superoxide dismutase, catalase, and glutathione peroxidase gene and protein expression, which was abolished by VP. RGFP966 inhibited hypothermic preservation-induced overexpression of B-cell lymphoma protein 2 (Bcl-2)-associated X (Bax) and cleaved caspase-3, increased Bcl-2 mRNA and protein expression, and reduced cardiomyocyte apoptosis. The antioxidant and anti-apoptotic effects of RGFP966 were cancelled by VP. The results suggest that supplementation of Celsior solution with RGFP966 attenuated prolonged hypothermic preservation-induced cardiac dysfunction. The mechanism may involve inhibition of oxidative stress and apoptosis via inactivation of the YAP pathway.

miR-375 affects the proliferation and invasion of hepatoma cells via targetingYAP / 中国肿瘤生物治疗杂志

@# Objective: To investigate the mechanisms of miR-375 affecting the proliferation and invasion of hepatoma cells via targeting YAP (Yes-associated protein). Methods: The cancerous tissues and corresponding para-cancerous tissues of 70 patients with hepatocellular carcinoma (HCC) who underwent surgical resection at the Second Affiliated Hospital of Henan University of Traditional Chinese Medicine from January 2015 to December 2016, as well as the hepatoma cell lines SMMC-7721, Hb611, HepG2 and BEL-7405 were collected for this study. qPCR method was used to detect the expression level of miR-375 in collected HCC tissues and different hepatoma cell lines; Dual luciferase reporter gene assay was used to verify the interaction between miR-375 and YAP; The relationship between miR-375 and clinicopathological features of HCC patients was also analyzed; MTT assay was used to detect the effect of miR375 on the proliferation of hepatoma cells; Transwell invasion assay was used to detect the invasive ability of hepatoma cells after inhibiting the expression of miR-375; Western blotting was used to detect the expression of YAP in HepG2 cells. The nude mouse model of subcutaneously transplanted xenograft was established, and the tumor volume and mass of transplanted hepatoma cells were detected after inhibiting the expression of miR-375. The expression of YAP in xenograft of nude mice was detected by immunohistochemistry and Western blotting. Results: The expression of miR-375 and YAP in HCC tissues was significantly higher than that in para-cancerous tissues (all P<0.05). The expression of miR-375 in HepG2 cells was the highest (P<0.05). miR-375 could specifically bind to the 3' UTR of YAP and regulate the expression activity of YAP. After inhibiting the expression of miR-375, the proliferation and invasion abilities of HepG2 cells were reduced (all P<0.05); The tumor volume and mass of transplanted xenografts were significantly reduced (both P<0.05); The expression of YAP protein in the transplanted xenografts was down-regulated (P<0.05). Conclusion: miR-375 plays an important role in the occurrence and development of liver cancer, and can influence the malignant biological behaviors of hepatoma cells by targeting and regulating the expression ofYAP.

Yes-Associated Protein Expression Is Correlated to the Differentiation of Prostate Adenocarcinoma

BACKGROUND: Yes-associated protein (YAP) in the Hippo signaling pathway is a growth control pathway that regulates cell proliferation and stem cell functions. Abnormal regulation of YAP was reported in human cancers including liver, lung, breast, skin, colon, and ovarian cancer. However, the function of YAP is not known in prostate adenocarcinoma. The purpose of this study was to investigate the role of YAP in tumorigenesis, differentiation, and prognosis of prostate adenocarcinoma. METHODS: The nuclear and cytoplasmic expression of YAP was examined in 188 cases of prostate adenocarcinoma using immunohistochemistry. YAP expression levels were evaluated in the nucleus and cytoplasm of the prostate adenocarcinoma and the adjacent normal prostate tissue. The presence of immunopositive tumor cells was evaluated and interpreted in comparison with the patients’ clinicopathologic data. RESULTS: YAP expression levels were not significantly different between normal epithelial cells and prostate adenocarcinoma. However, YAP expression level was significantly higher in carcinomas with a high Gleason grades (8–10) than in carcinomas with a low Gleason grades (6–7) (p < .01). There was no statistical correlation between YAP expression and stage, age, prostate-specific antigen level, and tumor volume. Biochemical recurrence (BCR)–free survival was significantly lower in patients with high YAP expressing cancers (p = .02). However high YAP expression was not an independent prognostic factor for BCR in the Cox proportional hazards model. CONCLUSIONS: The results suggested that YAP is not associated with prostate adenocarcinoma development, but it may be associated with the differentiation of the adenocarcinoma. YAP was not associated with BCR.

The effect of occult HBV infection on carcinogenesis of cryptogenic hepatocellular carcinoma / 中华肝胆外科杂志

Objective To investigate the effect of occult HBV infection (OBI) on carcinogenesis of cryptogenic hepatocellular carcinoma.Methods Samples of hepatocellular carcinoma (HCC) and pericarcinomatous tissues obtained after hepatectomy from January 2011 to November 2013 at the Third Affiliated Hospital of Sun Yat-Sen University were collected.They were divided into two groups:the cryptogenic HCC group (the CH group,n =26) and the HBV related HCC group (the HH group,n =40).These samples were compared with the normal liver tissues obtained in 30 patients.HBV DNA was identified by the nested polymerase chain reaction and the immunohistochemical method was taken to examine the hepatitis B virus X protein (HBx) and Yes-associated protein (YAP) expressions.Results OBI was identified in 20 (77.8％) cryptogenic HCC patients and 8 (26.7％) in the control group.There was a significant difference between the two groups (x2 =14.072,P ＜ 0.05).HBV DNA was detected in all the HBV-related HCC patients.The HBx protein expression was mainly located in the cytoplasm of liver cells and liver cancer cells,but YAP was expressed in the nucleus.Both of them showed diffuse brown or tan particles.In the HH group and the CH group,the positive expression rates of HBx protein in the tumorous tissues were 80.0％ and 90.0％,respectively,and 85.0％ and 82.5％ in the nontumorous tissues,but only in 40.0％ in the control group.The positive expression rates of YAP in the tumorous tissues were 65.0％ and 67.5％,respectively,15.0％ and 20.0％ in the nontumorous tissues,respectively,but only in 12.5％ in the control group.The HBx expression in the cancerous tissues and para-cancerous tissues of the HH group and the CH group showed no significant difference (P ＞ 0.05),but the YAP expression in the tumor tissues was significantly higher than that in the nontumorous tissues (P ＜ 0.05).The HBx and YAP expressions in the HH group were comparable to the CH group (P ＞ 0.05).However,their expressions in the cancerous tissue of the HH group and the CH group were significantly higher than in the normal liver tissues (P ＜ 0.05).Conclusion A high prevalence of HBV infection was observed in HBsAg-negative HCC and the high expressions of HBx and YAP might be involved in the process of cryptogenic hepatocellular carcinoma.