Publications by authors named "Ximei Wu"

55 Publications

RhoA/Rock activation represents a new mechanism for inactivating Wnt/β-catenin signaling in the aging-associated bone loss.

Cell Regen 2021 Mar 3;10(1). Epub 2021 Mar 3.

Department of Pharmacology, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, 310058, China.

The Wnt/β-catenin signaling pathway appears to be particularly important for bone homeostasis, whereas nuclear accumulation of β-catenin requires the activation of Rac1, a member of the Rho small GTPase family. The aim of the present study was to investigate the role of RhoA/Rho kinase (Rock)-mediated Wnt/β-catenin signaling in the regulation of aging-associated bone loss. We find that Lrp5/6-dependent and Lrp5/6-independent RhoA/Rock activation by Wnt3a activates Jak1/2 to directly phosphorylate Gsk3β at Tyr216, resulting in Gsk3β activation and subsequent β-catenin destabilization. In line with these molecular events, RhoA loss- or gain-of-function in mouse embryonic limb bud ectoderms interacts genetically with Dkk1 gain-of-function to rescue the severe limb truncation phenotypes or to phenocopy the deletion of β-catenin, respectively. Likewise, RhoA loss-of-function in pre-osteoblasts robustly increases bone formation while gain-of-function decreases it. Importantly, high RhoA/Rock activity closely correlates with Jak and Gsk3β activities but inversely correlates with β-catenin signaling activity in bone marrow mesenchymal stromal cells from elderly male humans and mice, whereas systemic inhibition of Rock therefore activates the β-catenin signaling to antagonize aging-associated bone loss. Taken together, these results identify RhoA/Rock-dependent Gsk3β activation and subsequent β-catenin destabilization as a hitherto uncharacterized mechanism controlling limb outgrowth and bone homeostasis.
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http://dx.doi.org/10.1186/s13619-020-00071-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7925793PMC
March 2021

COVID-19 and inhibitors of the renin-angiotensin-aldosterone system.

Expert Rev Anti Infect Ther 2020 Nov 26:1-2. Epub 2020 Nov 26.

Department of Pharmacology, School of Medicine, Zhejiang University , Hangzhou City, China.

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http://dx.doi.org/10.1080/14787210.2021.1851197DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711737PMC
November 2020

IRF3 prevents colorectal tumorigenesis via inhibiting the nuclear translocation of β-catenin.

Nat Commun 2020 11 13;11(1):5762. Epub 2020 Nov 13.

Institute of Immunology and Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, 310003, Hangzhou, China.

Occurrence of Colorectal cancer (CRC) is relevant with gut microbiota. However, role of IRF3, a key signaling mediator in innate immune sensing, has been barely investigated in CRC. Here, we unexpectedly found that the IRF3 deficient mice are hyper-susceptible to the development of intestinal tumor in AOM/DSS and Apc models. Genetic ablation of IRF3 profoundly promotes the proliferation of intestinal epithelial cells via aberrantly activating Wnt signaling. Mechanically, IRF3 in resting state robustly associates with the active β-catenin in the cytoplasm, thus preventing its nuclear translocation and cell proliferation, which can be relieved upon microbe-induced activation of IRF3. In accordance, the survival of CRC is clinically correlated with the expression level of IRF3. Therefore, our study identifies IRF3 as a negative regulator of the Wnt/β-catenin pathway and a potential prognosis marker for Wnt-related tumorigenesis, and describes an intriguing link between gut microbiota and CRC via the IRF3-β-catenin axis.
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http://dx.doi.org/10.1038/s41467-020-19627-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7666182PMC
November 2020

T851I mutation of human large tumor suppressor 1 disrupts its kinase activity and tumor-suppressor functions.

Life Sci 2021 Jan 24;264:118655. Epub 2020 Oct 24.

Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China. Electronic address:

Aim: Large tumor suppressor 1 (LATS1) is a Ser/Thr kinase to mediate Hippo signaling pathway and plays a pivotal role in tumor suppression. By searching the COSMIC database, we found a somatic missense mutation (NM_004690.4:c.2552C>T) of human LATS1 (NP_004681.1:p.851T>I) in two colorectal cancer cell lines, and investigated the role and underlying mechanism of this mutation in the colorectal tumorigenesis.

Main Methods: We performed structural and biochemistry analyses to investigate the role of LATS1 T851I mutation in Hippo signaling activation and used the mouse xenograft model to assess the role of this mutation in the colorectal tumorigenesis.

Key Findings: By structural and biochemistry approaches, we propose that T851 is an active residue other than Ser909 on the activation loop and is essential for LATS1 phosphorylation and kinase activity. We then reveal that T851I mutation in LATS1 not only destabilizes the phospho-Thr1079-LATS1, a prerequisite of LATS1 kinase activity, but also reduces its binding to the downstream effectors, YAP and TAZ. As a result, T851I mutation in LATS1 attenuates Hippo signaling and decreases its tumor-suppressor functions in the colorectal cancer.

Significance: The present study identifies the T851 as an essential residue for LATS1 kinase activity and uncovers the T851I mutation of LATS1 and consequent Hippo signaling suppression as a hitherto uncharacterized mechanism controlling colorectal tumorigenesis.
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http://dx.doi.org/10.1016/j.lfs.2020.118655DOI Listing
January 2021

Ascorbic acid enhances low-density lipoprotein receptor expression by suppressing proprotein convertase subtilisin/kexin 9 expression.

J Biol Chem 2020 11 10;295(47):15870-15882. Epub 2020 Sep 10.

Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, School of Food and Biological Engineering, Hefei University of Technology, Hefei, China. Electronic address:

Ascorbic acid, a water-soluble antioxidant, regulates various biological processes and is thought to influence cholesterol. However, little is known about the mechanisms underpinning ascorbic acid-mediated cholesterol metabolism. Here, we determined if ascorbic acid can regulate expression of proprotein convertase subtilisin/kexin 9 (PCSK9), which binds low-density lipoprotein receptor (LDLR) leading to its intracellular degradation, to influence low-density lipoprotein (LDL) metabolism. At cellular levels, ascorbic acid inhibited PCSK9 expression in HepG2 and Huh7 cell lines. Consequently, LDLR expression and cellular LDL uptake were enhanced. Similar effects of ascorbic acid on PCSK9 and LDLR expression were observed in mouse primary hepatocytes. Mechanistically, ascorbic acid suppressed PCSK9 expression in a forkhead box O3-dependent manner. In addition, ascorbic acid increased LDLR transcription by regulating sterol regulatory element-binding protein 2. , administration of ascorbic acid reduced serum PCSK9 levels and enhanced liver LDLR expression in C57BL/6J mice. Reciprocally, lack of ascorbic acid supplementation in L-gulono-γ-lactone oxidase deficient () mice increased circulating PCSK9 and LDL levels, and decreased liver LDLR expression, whereas ascorbic acid supplementation decreased PCSK9 and increased LDLR expression, ameliorating LDL levels in mice fed a high fat diet. Moreover, ascorbic acid levels were negatively correlated to PCSK9, total and LDL levels in human serum samples. Taken together, these findings suggest that ascorbic acid reduces PCSK9 expression, leading to increased LDLR expression and cellular LDL uptake. Thus, supplementation of ascorbic acid may ameliorate lipid profiles in ascorbic acid-deficient species.
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http://dx.doi.org/10.1074/jbc.RA120.015623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7681026PMC
November 2020

IL-4/IL-13 upregulates Sonic hedgehog expression to induce allergic airway epithelial remodeling.

Am J Physiol Lung Cell Mol Physiol 2020 05 4;318(5):L888-L899. Epub 2020 Mar 4.

Department of Respiratory Medicine, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.

We have previously demonstrated that upregulation of Sonic hedgehog (SHH) expression in allergic airway epithelia essentially contributes to the goblet cell metaplasia and mucous hypersecretion. However, the mechanism underlying the upregulation of SHH expression remains completely unknown. In cultured human airway epithelial cells, IL-4/IL-13 but not IL-5 robustly induces the mRNA and protein expression of SHH and in turn activates SHH signaling by promoting the JAK/STAT6-controlling transcription of gene. Moreover, intratracheal instillation of IL-4 and/or IL-13 robustly activates STAT6 and concomitantly upregulates SHH expression in mouse airway epithelia, whereas, in Club cell 10-kDa protein (CC10)-positive airway epithelial cells of children with asthma, activated STAT6 closely correlates with the increased expression of SHH and high activity of SHH signaling. Finally, intratracheal inhibition of STAT6 by AS-1517499 significantly diminished the allergen-induced upregulation of SHH expression, goblet cell phenotypes, and airway hyperresponsiveness, in an ovalbumin- or house dust mite-induced mouse model with allergic airway inflammation,. Together, upregulation of SHH expression by IL-4/IL-13-induced JAK/STAT6 signaling contributes to allergic airway epithelial remodeling, and this study thus provides insight into how morphogen signaling is coordinated with Th2 cytokine pathways to regulate tissue remodeling in chronic airway diseases.
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http://dx.doi.org/10.1152/ajplung.00186.2019DOI Listing
May 2020

Dengue control in Pakistan: prior planning is better than controlling too late.

BMJ 2019 12 12;367:l6912. Epub 2019 Dec 12.

Department of Pharmacology, Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City, 310058, China.

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http://dx.doi.org/10.1136/bmj.l6912DOI Listing
December 2019

Protein tyrosine phosphatase 11 acts through RhoA/ROCK to regulate eosinophil accumulation in the allergic airway.

FASEB J 2019 11 30;33(11):11706-11720. Epub 2019 Jul 30.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou, China.

Src homology domain 2-containing protein tyrosine phosphatase 2 (SHP2) participates in multiple cell functions including cell shape, movement, and differentiation. Therefore, we investigated the potential role of SHP2 in eosinophil recruitment into lungs in allergic airway inflammation and explored the underlying mechanism. Both SHP2 and Ras homolog family member A (RhoA) kinase were robustly activated in the airway eosinophils of children with allergic asthma and of a mouse model with allergic airway inflammation. Moreover, inhibition of SHP2 activity by its specific inhibitors reverses the dephosphorylation of p190-A Rho GTPase-activating protein and in turn attenuates RhoA/Rho-associated protein kinase (ROCK) signaling, resulting in the attenuation of eosinophil migration in response to platelet-activating factor stimulation. Specifically, deletion in myeloid cells did not affect the number and classification of circulating leukocytes but significantly attenuated the allergen-induced inflammatory cell, especially eosinophil, infiltration into lungs, and airway hyperreactivity. Notably, genetic interaction between and indicated that RhoA inactivation and deletion synergistically attenuated the allergen-induced eosinophil infiltration into lungs and airway hyperreactivity, whereas overexpression of active RhoA robustly restored the deletion-resultant attenuation of allergen-induced eosinophil recruitment into lungs and airway hyperreactivity as well. Thus, this study demonstrates that SHP2 RhoA/ROCK signaling regulates eosinophil recruitment in allergic airway inflammation and possibly in allergic asthma.-Xu, C., Wu, X., Lu, M., Tang, L., Yao, H., Wang, J., Ji, X., Hussain, M., Wu, J., Wu, X. Protein tyrosine phosphatase 11 acts through RhoA/ROCK to regulate eosinophil accumulation in the allergic airway.
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http://dx.doi.org/10.1096/fj.201900698RDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6902720PMC
November 2019

[Association of polymorphisms of miR-146a rs2910164 locus with clinical features of rheumatoid arthritis].

Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2019 May;36(5):505-507

Department of Rheumatology, People's Hospital of Longhua District of Shenzhen, Shenzhen, Guangdong 518109, China. Email:

Objective: To assess the association of single nucleotide polymorphisms (SNPs) of microRNA-146a (miR-146a) with clinical features of rheumatoid arthritis (RA).

Methods: In 126 patients with RA and 102 matched healthy controls, SNPs of miR-146a rs2910164 locus were determined with a high-resolution melting method. The association of such polymorphisms with disease activity score in 28 joints (DAS28) and clinical features of RA was assessed.

Results: The distribution of SNPs of miR-146a rs2910164 among RA patients did not differ from that of the control group. No significant association was found between miR-146a rs2910164 polymorphism with DAS28. However, RA patients with a GG genotype had a greater chance to develop extra-articular manifestations (P<0.01).

Conclusion: Polymorphisms of miR-146a rs2910164 locus is not an independent risk factor for RA, though its GG genotype may be associated with extra-articular manifestations of RA.
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http://dx.doi.org/10.3760/cma.j.issn.1003-9406.2019.05.023DOI Listing
May 2019

A CRTH2 antagonist, CT-133, suppresses NF-κB signalling to relieve lipopolysaccharide-induced acute lung injury.

Eur J Pharmacol 2019 Jul 3;854:79-91. Epub 2019 Apr 3.

Department of Critical Care Medicine and Orthopedics, The First Affiliated Hospital, Zhejiang University, School of Medicine, Hangzhou City, 310009, China. Electronic address:

Acute lung injury (ALI) and acute respiratory distress syndrome are life-threatening conditions that still have no definite pharmacotherapy. Hence, we investigate the potential effectiveness and underlying mechanism of CT-133, a newly developed selective antagonist of prostaglandin D2 receptor 2 (DP2) or of chemoattractant receptor homologous molecule expressed on Th2 cells (CRTH2), against lipopolysaccharide (LPS)-induced ALI. CT-133 (10 or 30 mg/kg) or dexamethasone (1 mg/kg, positive control) were intragastrically administered 1 h before and 12 h after intratracheal LPS instillation, and primary neutrophils and macrophages and RAW264.7 macrophages were used to investigate the role of CT-133 in regulation of their functions. LPS induced a significant secretion of PGD from primary macrophages, however, CT-133 dose-dependently and markedly decreased the infiltration of neutrophils and macrophages into lungs, reduced the IL-1β, TNF-α, IL-6, and KC levels in broncho-alveolar lavage (BAL) fluids, decreased the wet weight and myeloperoxidase activity of lungs, reduced Evans blue and albumin exudation into lungs, and improved the lung histopathological changes and hypoxemia. Moreover, CT-133 significantly suppressed the primary neutrophil migration toward the PGD and robustly inhibited the mRNA and protein expression of IL-1β, TNF-α, IL-6, and KC in primary and RAW264.7 macrophages in response to either LPS- or PGD stimulation. Finally, CT-133 significantly blocked the LPS-induced P65 activation in both RAW264.7 macrophages and mouse lungs. Thus, This is the first report that a CRTH2 antagonist, CT-133, is capable of significantly alleviating LPS-induced lung injury by probably down-regulating the NF-κB signalling.
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http://dx.doi.org/10.1016/j.ejphar.2019.03.053DOI Listing
July 2019

CRTH2 antagonist, CT‑133, effectively alleviates cigarette smoke-induced acute lung injury.

Life Sci 2019 Jan 22;216:156-167. Epub 2018 Nov 22.

Department of Pharmacology, Zhejiang University, School of Medicine, Hangzhou City 310058, China. Electronic address:

Aims: Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), characterized by overwhelming lung inflammation, are associated with high mortality. Cigarette smoke (CS) is one of the major causes of ALI/ARDS. Since high expression of prostaglandin (PG) D has been observed in CS-induced lung injury. Currently, no effective pharmacological therapies are available to treat ALI, and supportive therapies remain the mainstay of treatment. Therefore, we investigated the protective effect of CT‑133, a newly discovered selective CRTH2 antagonist, on CS-induced ALI in vivo and in vitro.

Main Methods: CT‑133 (10 and 30 mg/kg), dexamethasone (1 mg/kg) and normal saline were intratracheally administrated 1 hr prior to whole-body CS-exposure for seven consecutive days to study the key characteristics of ALI. Subsequently, CSE (4%)- and PGD-stimulated RAW 264.7 macrophages were used to evaluate the protective effect of CT‑133.

Key Findings: CT‑133 remarkably attenuated infiltration of inflammatory cells, neutrophils, and macrophages in the BALF, albumin contents, expression of IL‑1β, IL‑6, TNF‑α and KC, lung myeloperoxidase (MPO) activity and lung histopathological alterations caused by CS exposure in mice. Moreover, CT‑133 not only reversed the uncontrolled secretion of IL‑1β, IL-6, TNF‑α and KC from CSE- and PGD-stimulated RAW 264.7 macrophages but also augmented IL-10 production in both in vivo and in vitro studies. Additionally, CT‑133 alleviated in vitro neutrophil migration chemoattracted by PGD.

Significance: Our results provide the first evidence that targeting CRTH2 could be a new potential therapeutic option to treat CS-induced ALI.
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http://dx.doi.org/10.1016/j.lfs.2018.11.039DOI Listing
January 2019

Antenatal exposure to betamethasone induces placental 11β-hydroxysteroid dehydrogenase type 2 expression and the adult metabolic disorders in mice.

PLoS One 2018 13;13(9):e0203802. Epub 2018 Sep 13.

Department of Endocrinology, the Children Hospital, School of Medicine, Zhejiang University, Hangzhou, China.

Antenatal overexposure to glucocorticoids causes fetal intrauterine growth restriction (IUGR) and adult metabolic disorders. 11β-hydroxysteroid dehydrogenase (11β-HSD) 1 and 2 are key enzymes for glucocorticoid metabolism, however, the detailed effects of antenatal overexposure to glucocorticoids on placental 11β-HSD1 and 2 expression and adult metabolic disorders remain obscure. Here, we report that, in placenta 11β-HSD1 is diffusely localized, whereas 11β-HSD2 is specifically expressed in labyrinthine layer. Exposure of pregnant dams to betamethasone significantly increases the expression of placental 11β-HSD2 but not 11β-HSD1, and decreases the weights of fetuses but not placentas. Antenatal exposure to betamethasone leads to either significant weight loss in the offspring younger than 10-week-old, or weight gain in those older than 14-week-old. Furthermore, antenatal exposure to betamethasone results in coexistence of various metabolic disorders in adult offspring, including hyperglycemia, glucose intolerance, low insulin secretory capacity and hyperlipidemia. The present study demonstrates that exposure of pregnant dams to betamethasone induces the expression of placental 11β-HSD2 but not 11β-HSD1, leads to fetal IUGR and causes adult metabolic disorders, providing evidence for fetal origins of adult diseases and the potential role of placental 11β-HSD2 in them.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0203802PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6136781PMC
March 2019

Inhibition of p21-activated kinase 1 attenuates the cardinal features of asthma through suppressing the lymph node homing of dendritic cells.

Biochem Pharmacol 2018 08 12;154:464-473. Epub 2018 Jun 12.

Department of Pharmacology and Key Laboratory of CFDA for Respiratory Drug Research, Zhejiang University School of Medicine, Hangzhou 310058, China. Electronic address:

Dendritic cell (DC) trafficking from lung to the draining mediastinal lymph nodes (MLNs) is a key step for initiation of T cell responses in allergic asthma. In the present study, we investigate the role of DC-mediated airway inflammation after inhibition of p21-activated kinase-1 (PAK1), an effector of Rac and Cdc42 small GTPases, in the allergen-induced mouse models of asthma. Systemic administration of PAK1 specific inhibitor IPA-3 significantly attenuates not only the airway inflammation but also the airway hyperresponsiveness in a mouse model of ovalbumin-induced asthma. Specifically, intratracheal administration of low dosage of IPA-3 consistently decreases not only the airway inflammation but also the DC trafficking from lung to the MLNs. Importantly, intratracheal instillation of IPA-3-treated and ovalbumin-pulsed DCs behaves largely the same as that of either Rac inhibitor-treated and ovalbumin-pulsed DCs or Cdc42 inhibitor-treated and ovalbumin-pulsed DCs in attenuation of the airway inflammation in ovalbumin-challenged mice. Mechanistically, PAK1 is not involved in the maturation, apoptosis, antigen uptake, and T cell activation of cultured DCs, but PAK1 dose lie on the downstream of Rac and Cdc42 to regulate the DC migration toward the chemokine C-C motif chemokine ligand 19. Taken together, this study demonstrates that inhibition of PAK1 attenuates the cardinal features of asthma through suppressing the DC trafficking from lung to the MLN, and that interfere with DC trafficking by a PAK1 inhibitor thus holds great promise for the therapeutic intervention of allergic diseases.
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http://dx.doi.org/10.1016/j.bcp.2018.06.012DOI Listing
August 2018

High expression of Sonic hedgehog in allergic airway epithelia contributes to goblet cell metaplasia.

Mucosal Immunol 2018 09 4;11(5):1306-1315. Epub 2018 Jun 4.

Department of Pharmacology, Zhejiang University School of Medicine, 310058, Hangzhou, China.

Sonic hedgehog (SHH) is abundantly expressed and critical for morphogenesis in embryonic lungs; however, SHH expression drops to a much lower level in mice from E17.5 and in humans from the 21st gestational week. We find that SHH expression is robustly upregulated in the airway epithelia of children with asthma or mouse models with allergic airway disease. Specifically, airway-specific SMO loss of function significantly suppresses allergen-induced goblet cell phenotypes, whereas an airway-specific SMO gain of function markedly enhances the goblet cell phenotypes in mouse models with allergic airway disease. Notably, intratracheal administration with SHH-neutralizing antibody or cyclopamine robustly attenuates goblet cell phenotypes in mouse models with allergic airway disease. Finally, we identify that Muc5AC gene encoding MUC5AC mucin serves as a direct target of GLI transcriptional factors in response to SHH, whereas the SAM-pointed domain-containing ETS transcription factor and Forkhead box A2, critical transcriptional factors for goblet cell phenotypes, both function as the effectors of GLIs in response to SHH stimulation. Together, the upregulation of SHH expression in allergic bronchial epithelia contributes to goblet cell metaplasia; thus, blockage of SHH signaling is a rational approach in a therapeutic intervention of epithelial remodeling in chronic airway diseases.
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http://dx.doi.org/10.1038/s41385-018-0033-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6160330PMC
September 2018

Acute Respiratory Distress Syndrome: Bench-to-Bedside Approaches to Improve Drug Development.

Clin Pharmacol Ther 2018 09 27;104(3):484-494. Epub 2018 Feb 27.

Department of Pharmacology, Hangzhou City, 310058, China.

Despite 50 years of extensive research, no definite drug is currently available to treat acute respiratory distress syndrome (ARDS), and the supportive therapies remain the mainstay of treatment. To improve drug development for ARDS, researchers need to deeply analyze the "omics" approaches, reevaluate the suitable therapeutic targets, resolve the problems of inadequate animal modeling, develop the strategies to reduce the heterogeneity, and reconsider new therapeutic and analytical approaches for better designs of clinical trials.
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http://dx.doi.org/10.1002/cpt.1034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7162218PMC
September 2018

Cdc42 Is Essential for Both Articular Cartilage Degeneration and Subchondral Bone Deterioration in Experimental Osteoarthritis.

J Bone Miner Res 2018 05 15;33(5):945-958. Epub 2018 Feb 15.

Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou, China.

Cdc42, a member of Rho family small guanosine triphosphatases (GTPases), is critical for cartilage development. We investigated the roles of Cdc42 in osteoarthritis and explored the potential mechanism underlying Cdc42-mediated articular cartilage degeneration and subchondral bone deterioration. Cdc42 is highly expressed in both articular cartilage and subchondral bone in a mouse osteoarthritis model with surgical destabilization of the medial meniscus (DMM) in the knee joints. Specifically, genetic disruption of Cdc42, knockdown of Cdc42 expression, or inhibition of Cdc42 activity robustly attenuates the DMM-induced destruction, hypertrophy, high expression of matrix metallopeptidase-13 and collagen X, and activation of Stat3 in articular cartilages. Notably, genetic disruption of Cdc42, knockdown of Cdc42 expression or inhibition of Cdc42 activity significantly restored the increased numbers of mesenchymal stem cells, osteoprogenitors, osteoblasts, osteoclasts, and neovascularized vessels, the increased bone mass, and the activated Erk1/2, Smad1/5 and Smad2 in subchondral bone of DMM-operated mice. Mechanistically, Cdc42 mediates interleukin-1β-induced interleukin-6 production and subsequent Jak/Stat3 activation to regulate chondrocytic inflammation, and also lies upstream of Erk/Smads to regulate subchondral bone remodeling during transform growth factor-β1 signaling. Cdc42 is apparently required for both articular cartilage degeneration and subchondral bone deterioration of osteoarthritis, thus, interventions targeting Cdc42 have potential in osteoarthritic therapy. © 2018 American Society for Bone and Mineral Research.
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http://dx.doi.org/10.1002/jbmr.3380DOI Listing
May 2018

Notch Signaling: Linking Embryonic Lung Development and Asthmatic Airway Remodeling.

Mol Pharmacol 2017 12 12;92(6):676-693. Epub 2017 Oct 12.

Department of Pharmacology and The Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City, China (M.H., C.X., M.A., Xim.W.); The Second People's Hospital of Wenling, Wenling City, Zhejiang Province, China (Y.Y.); and Department of Respiratory Medicine, the Affiliated Children Hospital, School of Medicine, Zhejiang University, Hangzhou City, China (M.L., Xil.W., L.T.)

Lung development is mediated by assorted signaling proteins and orchestrated by complex mesenchymal-epithelial interactions. Notch signaling is an evolutionarily conserved cell-cell communication mechanism that exhibits a pivotal role in lung development. Notably, both aberrant expression and loss of regulation of Notch signaling are critically linked to the pathogenesis of various lung diseases, in particular, pulmonary fibrosis, lung cancer, pulmonary arterial hypertension, and asthmatic airway remodeling; implying that precise regulation of intensity and duration of Notch signaling is imperative for appropriate lung development. Moreover, evidence suggests that Notch signaling links embryonic lung development and asthmatic airway remodeling. Herein, we summarized all-recent advances associated with the mechanistic role of Notch signaling in lung development, consequences of aberrant expression or deletion of Notch signaling in linking early-impaired lung development and asthmatic airway remodeling, and all recently investigated potential therapeutic strategies to treat asthmatic airway remodeling.
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http://dx.doi.org/10.1124/mol.117.110254DOI Listing
December 2017

Wnt/β-catenin signaling links embryonic lung development and asthmatic airway remodeling.

Biochim Biophys Acta Mol Basis Dis 2017 12 1;1863(12):3226-3242. Epub 2017 Sep 1.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou City 310058, China; The Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City 310058, China. Electronic address:

Embryonic lung development requires reciprocal endodermal-mesodermal interactions; mediated by various signaling proteins. Wnt/β-catenin is a signaling protein that exhibits the pivotal role in lung development, injury and repair while aberrant expression of Wnt/β-catenin signaling leads to asthmatic airway remodeling: characterized by hyperplasia and hypertrophy of airway smooth muscle cells, alveolar and vascular damage goblet cells metaplasia, and deposition of extracellular matrix; resulting in decreased lung compliance and increased airway resistance. The substantial evidence suggests that Wnt/β-catenin signaling links embryonic lung development and asthmatic airway remodeling. Here, we summarized the recent advances related to the mechanistic role of Wnt/β-catenin signaling in lung development, consequences of aberrant expression or deletion of Wnt/β-catenin signaling in expansion and progression of asthmatic airway remodeling, and linking early-impaired pulmonary development and airway remodeling later in life. Finally, we emphasized all possible recent potential therapeutic significance and future prospectives, that are adaptable for therapeutic intervention to treat asthmatic airway remodeling.
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http://dx.doi.org/10.1016/j.bbadis.2017.08.031DOI Listing
December 2017

Twa1/Gid8 is a β-catenin nuclear retention factor in Wnt signaling and colorectal tumorigenesis.

Cell Res 2017 Dec 22;27(12):1422-1440. Epub 2017 Aug 22.

Department of Cell Biology and Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.

Hyperactivation of Wnt/β-catenin signaling is one of the major causes of human colorectal cancer (CRC). A hallmark of Wnt signaling is the nuclear accumulation of β-catenin. Although β-catenin nuclear import and export have been widely investigated, the underlying mechanism of β-catenin's nuclear retention remains largely unknown. Here, we report that Twa1/Gid8 is a key nuclear retention factor for β-catenin during Wnt signaling and colorectal carcinogenesis. In the absence of Wnt, Twa1 exists together with β-catenin in the Axin complex and undergoes ubiquitination and degradation. Upon Wnt signaling, Twa1 translocates into the nucleus, where it binds and retains β-catenin. Depletion of Twa1 attenuates Wnt-stimulated gene expression, dorsal development of zebrafish embryos and xenograft tumor growth of CRC cells. Moreover, nuclear Twa1 is significantly upregulated in human CRC tissues, correlating with the nuclear accumulation of β-catenin and poor prognosis. Thus, our results identify Twa1 as a previously undescribed regulator of the Wnt pathway for promoting colorectal tumorigenesis by facilitating β-catenin nuclear retention.
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http://dx.doi.org/10.1038/cr.2017.107DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5717399PMC
December 2017

Vitamin C deficiency exacerbates diabetic glomerular injury through activation of transforming growth factor-β signaling.

Biochim Biophys Acta Gen Subj 2017 Sep 23;1861(9):2186-2195. Epub 2017 Jun 23.

Department of Pharmacology, Zhejiang University Medical School, Hangzhou 310058, China. Electronic address:

Background: The hyperglycemia and hyperoxidation that characterize diabetes lead to reduced vitamin C (VC) in diabetic humans and experimentally diabetic animals. Herein, we access the effects of VC deficiency on the diabetic kidney injury and explore the underlying mechanism.

Methods: l-gulonolactone oxidase conventional knockout (Gulo) mice genetically unable to synthesize VC were subjected to streptozotocin-induced diabetic kidney injury and the role of VC deficiency was evaluated by biochemical and histological approaches. Rat mesangial cells were cultured to investigate the underlying mechanism.

Results: Functionally, VC deficiency aggravates the streptozotocin-induced renal insufficiency, exhibiting the increased urine albumin, water intake, and urine volume in Gulo mice. Morphologically, VC deficiency exacerbates the streptozotocin-induced kidney injury, exhibiting the increased glomerular expansion, deposition of Periodic Acid-Schiff- and Masson-positive materials, and expression of α-smooth muscle actin, fibronectin and type 4 collagen in glomeruli of Gulo mice. Mechanistically, VC activates protein kinase B (Akt) to destabilize Ski and thereby induce the expression of Smad7, resulting in suppression of TGF-β/Smad signaling and extracellular matrix deposition in mesangial cells.

Conclusions: VC is essential for the renal function maintenance in diabetes.

General Significance: Compensation for the loss of VC could be an effective remedy for diabetic kidney injury.
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http://dx.doi.org/10.1016/j.bbagen.2017.06.018DOI Listing
September 2017

Inhibition of heat shock protein 90 rescues glucocorticoid-induced bone loss through enhancing bone formation.

J Steroid Biochem Mol Biol 2017 07 10;171:236-246. Epub 2017 Apr 10.

Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou, 310058, China. Electronic address:

Endogenous glucocorticoids (GCs) support normal bone development and bone mass maintenance, whereas long-term exposure to pharmacological dosages of GCs uncouples bone formation and resorption, resulting in GC-induced osteoporosis (GIOP). Heat shock protein 90 (HSP90) chaperoning glucocorticoid receptor (GR) signaling prompts us to speculate that HSP90 plays critical roles in GC-mediated bone formation and GIOP. In the present study, inhibition of HSP90 activity by 17-Demethoxy-17-allyaminogeldanmycin (17-AAG) or knockdown of HSP90 expression by siRNAs attenuated dexamethasone(Dex)-induced GR nuclear accumulation and transcriptional output of GR signaling, whereas overexpression of HSP90α or HSP90β enhanced GR transactivity in C3H10T1/2 cells. Though 17-AAG itself enhanced osteoblastic differentiation, it restored the Dex(10M)-induced and Dex(10M)-negated osteoblastic differentiation in C3H10T1/2 cells and primary calvarial osteoblasts. Moreover, systemic administration of 17-AAG to mice induced not only osteoclastogenesis but also osteoblastogenesis, whereas bone formation possibly exceeded bone resorption, eventually leading to the increased bone masses. Likewise, systemic administration of 17-AAG to mice restored GC-negated osteoblastogenesis and enhanced GC-induced osteoclastogenesis, similarly, 17-AAG-induced bone formation possibly exceeded both 17-AAG- and GC-induced bone resorption, eventually resulting in rescue of GIOP. Together, the present study has revealed that inhibition of HSP90 restores GIOP through enhancing bone formation, and our findings may help to shed light on the pathogenesis of GIOP and provide targets for the therapeutic intervention of the disease.
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http://dx.doi.org/10.1016/j.jsbmb.2017.04.004DOI Listing
July 2017

Inhibition of Myosin Light-Chain Kinase Enhances the Clearance of Lipopolysaccharide-Induced Lung Inflammation Possibly by Accelerating Neutrophil Apoptosis.

Shock 2017 09;48(3):377-386

*Department of Critical Care Medicine, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou City, China †Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou City, China ‡Department of Paediatrics, The First People's Hospital of Wenling City, Wenling City, China §Department of Respiratory Medicine, The Affiliated Children's Hospital, Zhejiang University School of Medicine, Hangzhou City, China.

Neutrophils are a population of inflammatory cells involved in acute lung injury (ALI), and lipopolysaccharide (LPS)-induced prolonged neutrophil survival and delayed neutrophil apoptosis hinder the alleviation of lung inflammation. Myosin light-chain kinase (MLCK) involved the RhoA/Rho kinase signaling pathway responsible for the cytoskeletal arrangement, and previous studies have revealed that inhibition of MLCK induces apoptosis in vitro and in vivo. In this study, glycogen-induced neutrophils isolated from rats or mice were incubated with ML-7, a MLCK-specific inhibitor, and LPS-induced ALI mice administrated with ML-7 were investigated, to demonstrate the roles of MLCK in neutrophil apoptosis as well as its possibility of contributing to the clearance of inflammation. We found that ML-7 dramatically promoted neutrophil apoptosis that possibly signal through the p38 to upregulate the expression of the apoptotic proteins caspase-9 and B-cell lymphoma 2 and to downregulate the expression of the antiapoptotic protein Bcl-2-associated X protein and myeloid cell leukemia-1. In mice, ML-7 accelerated the clearance of inflammation in LPS-induced ALI through attenuating neutrophil accumulation, histopathological changes, and pulmonary edema. ML-7 promoted elimination of inflammation possibly by accelerating neutrophil apoptosis and macrophage-mediated clearance. Moreover, ML-7 also reduced the LPS-induced production of proinflammatory cytokines interleukin-1β and tumor necrosis factor-α, and the activity of myeloperoxidase. Taken together, the present study uncovers a hitherto uncharacterized role of MLCK in neutrophil apoptosis that contributes to the alleviation of inflammation in response to LPS.
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http://dx.doi.org/10.1097/SHK.0000000000000863DOI Listing
September 2017

VEGF165 induces differentiation of hair follicle stem cells into endothelial cells and plays a role in in vivo angiogenesis.

J Cell Mol Med 2017 08 28;21(8):1593-1604. Epub 2017 Feb 28.

Research Institute of Orthopedics, The Second Affiliated Hospital, School of Medical, Zhejiang University, Hangzhou, China.

Within the vascular endothelial growth factor (VEGF) family of five subtypes, VEGF165 secreted by endothelial cells has been identified to be the most active and widely distributed factor that plays a vital role in courses of angiogenesis, vascularization and mesenchymal cell differentiation. Hair follicle stem cells (HFSCs) can be harvested from the bulge region of the outer root sheath of the hair follicle and are adult stem cells that have multi-directional differentiation potential. Although the research on differentiation of stem cells (such as fat stem cells and bone marrow mesenchymal stem cells) to the endothelial cells has been extensive, but the various mechanisms and functional forms are unclear. In particular, study on HFSCs' directional differentiation into vascular endothelial cells using VEGF165 has not been reported. In this study, VEGF165 was used as induction factor to induce the differentiation from HFSCs into vascular endothelial cells, and the results showed that Notch signalling pathway might affect the differentiation efficiency of vascular endothelial cells. In addition, the in vivo transplantation experiment provided that HFSCs could promote angiogenesis, and the main function is to accelerate host-derived neovascularization. Therefore, HFSCs could be considered as an ideal cell source for vascular tissue engineering and cell transplantation in the treatment of ischaemic diseases.
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http://dx.doi.org/10.1111/jcmm.13089DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5542910PMC
August 2017

[Cigarette smoking in different manners induces acute lung injury in rats].

Zhejiang Da Xue Xue Bao Yi Xue Ban 2016 May;45(5):522-529

Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China.

To investigate the effects of cigarette smoking in different manners on acute lung injury in rats. The commercially available cigarettes with tar of 1,5, 11 mg were smoked in Canada depth smoking (health canada method, HCM) manner, and those with tar of 11 mg were also smoked in international standard (ISO) smoking manner. Rats were fixed and exposed to mainstream in a manner of nose-mouth exposure. After 28 days, the bronchoalveolar lavage fluids from left lung were collected for counting and classification of inflammatory cells and determination of pro-inflammatory cytokines IL-1β and TNF-α. The right lungs were subjected to histological examination and determination of myeloperoxidase (MPO) and superoxide dismutase (SOD) activities and glutathione, reactive oxygen species (ROS) and malondialdehyde (MDA) levels. In both HCM and ISO manners, the degree of lung injury was closely related to the tar content of cigarettes, and significant decrease in the body weight of rats was observed after smoking for one week. In a HCM manner, smoking with cigarette of 11 mg tar resulted in robust infiltration of macrophages, lymphocytes and neutrophils into lungs, significant increase in IL-1β and TNF-α levels and MPO activities, and significant decrease in GSH levels and SOD activities and increase in ROS and MDA levels (all <0.05). Smoking with cigarette of 5 mg tar led to moderate increase in IL-1β and TNF-α levels, and MPO activities (all <0.05), and moderate decrease in GSH levels and SOD activities and increase of ROS and MDA levels (all <0.05). However, smoking with cigarette of 1 mg tar affected neither inflammatory cell infiltration nor IL-1β and TNF-α levels. Cigarette smoking in nose-mouth exposure manner can induce acute lung injury in rats; and the degree of lung injury is closely related to the content of tar and other hazards in cigarettes.
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May 2016

SUMOylation of large tumor suppressor 1 at Lys751 attenuates its kinase activity and tumor-suppressor functions.

Cancer Lett 2017 02 12;386:1-11. Epub 2016 Nov 12.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, China. Electronic address:

Large tumor suppressor (Lats) plays a critical role in maintaining cellular homeostasis and is the core to mediate Hippo growth-inhibitory signaling pathway. SUMOylation is a reversible and dynamic process that regulates a variety of cell functions. Here, we show that SUMOylation of Lats1 affects its kinase activity specifically towards Hippo signaling. Small ubiquitin-like modifier (SUMO) 1 interacts with and directly SUMOylates Lats1, whereas loss of SUMOylation pathway function disrupts Lats1 SUMOylation. Among potential SUMOylation sites on hLats1, K751 and K830 are conversed and essential for maintaining the transcriptional output of Hippo signaling, whereas K751 mutation more significantly abolishes SUMO1-induced Lats1 SUMOylation than K830 mutation. Though Lats1 SUMOylation at K751 affects neither its subcellular distribution nor its interactions with YAP and TAZ, it significantly destabilizes the phosphorylated Lats1 (Thr1079 but not Ser909), resulting in the attenuation of Lats1 kinase activity and inhibition of Hippo signaling. Moreover, HepG2 hepatocellular carcinoma cells express significantly more SUMOylated Lats1 than LO2 normal human hepatic cells, and in HepG2 cells or HepG2 cells xenografts, Lats1 SUMOylation at K751 consistently attenuates Lats1 kinase activity and subsequently suppresses Hippo signaling, resulting in not only the promotion of cell proliferation and colony formation but also the suppression of cell apoptosis. Together, we demonstrate that Lats1 SUMOylation at K751 suppresses its kinase activity and subsequently attenuates its tumor-suppressor functions. Thus, this study provides additional insight into how Hippo signaling is regulated and highlights the potentially critical role of Lats1 SUMOylation in tumor development.
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http://dx.doi.org/10.1016/j.canlet.2016.11.009DOI Listing
February 2017

Chemical constituents of tobacco smoke induce the production of interleukin-8 in human bronchial epithelium, 16HBE cells.

Tob Induc Dis 2016 19;14:24. Epub 2016 Jul 19.

Department of Pharmacology, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China.

Background: Interleukin-8 (IL-8) functions as a major chemoattractant and plays pivotal roles in the initiation and development of chronic obstructive pulmonary disease (COPD), and tobacco smoke is a most risk factor contributing to the development of COPD. Hence, we have screened some of the tobacco smoke-derived chemical compounds that potentially induce the production of IL-8 in human bronchial epithelium, 16HBE cells.

Methods: Twenty-eight hazardous smoke components belonging to 9 classes including nicotine, ammonia, aromatic amines, polycyclic aromatic hydrocarbons, phenols, carbonyls, hydrocyanic acid, nitrosamines and other volatile organics were used in the experiments. Proliferation of 16HBE cells was determined by cell counting kit-8 kit, luciferase activity was measured in IL-8 reporter gene-expressing 16HBE cells, and IL-8 levels in culture supernatants were quantified by enzyme-linked immunosorbent assay.

Results: At the non-toxic dosages, chemical compounds belonging to nicotine, aromatic amines, benzopyrene, phenols, aldehydes, and some other volatile organics dose-dependently increased IL-8 reporter gene expression. Consistently, the representative compounds belonging to nicotine, aromatic amines, benzopyrene, phenols, aldehydes, and some other volatile organics significantly and dose-dependently increased IL-8 levels in the culture supernatants of 16HBE cells, among these compounds, benzopyrene is a most potent stimulator for inducing IL-8 production.

Conclusions: The present study has identified particular tobacco smoke constituents responsible for inducing the IL-8 production in human bronchial epithelium, which might help shed light on the pathogenesis of tobacco smoke-induced COPD.
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http://dx.doi.org/10.1186/s12971-016-0089-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950078PMC
July 2016

Up-regulation of 11β-Hydroxysteroid Dehydrogenase Type 2 Expression by Hedgehog Ligand Contributes to the Conversion of Cortisol Into Cortisone.

Endocrinology 2016 09 5;157(9):3529-39. Epub 2016 Jul 5.

Department of Obstetrics and Gynaecology (H.Z.), The First Affiliated Hospital, and Department of Endocrinology (C.Z., W.X., L.T.), The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, People's Republic of China; and Department of Pharmacology (X.F., X.W., C.T.), School of Medicine, Zhejiang University, Hangzhou 310058, People's Republic of China.

The cortisol-inactivating enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) that catalyzes the intracellular inactivation of glucocorticoids plays a pivotal role in human pregnant maintenance and normal fetal development. Given the fact that the main components of Hedgehog (HH) signaling pathway are predominantly expressed in syncytial layer of human placental villi where 11β-HSD2 is robustly expressed, in the present study, we have investigated the potential roles and underlying mechanisms of HH signaling in 11β-HSD2 expression. Activation of HH signaling by a variety of approaches robustly induced 11β-HSD2 expression as well as the 11β-HSD2 activity, whereas suppression of HH signaling significantly attenuated 11β-HSD2 expression as well as the 11β-HSD2 activity in both human primary cytotrophoblasts and trophoblast-like BeWo cells. Moreover, among glioma-associated oncogene (GLI) family transcriptional factors in HH signaling, knockdown of GLI2 but not GLI1 and GLI3 significantly attenuated HH-induced 11β-HSD2 expression and activity, and overexpression of GLI2 activator alone was sufficient to induce 11β-HSD2 expression and activity. Finally, GLI2 not only directly bound to the promoter region of gene hsd11b2 to transactivate hsd11b2 but also formed a heterodimer with RNA polymerase II, an enzyme that catalyzes the transcription of DNA to synthesize mRNAs, resulting in up-regulation of hsd11b2 gene transcription. Taken together, the present study has uncovered a hitherto uncharacterized role of HH/GLI2 signaling in 11β-HSD2 regulation, implicating that HH signaling through GLI2 could be required for the human pregnant maintenance and fetal development.
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http://dx.doi.org/10.1210/en.2016-1286DOI Listing
September 2016

Smoothened-independent activation of hedgehog signaling by rearranged during transfection promotes neuroblastoma cell proliferation and tumor growth.

Biochim Biophys Acta 2016 09 15;1860(9):1961-72. Epub 2016 Jun 15.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, China. Electronic address:

Background: Rearranged during transfection (RET) proto-oncogene encodes a receptor tyrosine kinase for glial cell line-derived neurotrophic factor (GDNF) signaling, and high RET expression is closely related to the tumorigenesis and malignancy of neuroblastoma(NB).

Methods: We have investigated whether RET signals through hedgehog (HH) pathway in NB cell proliferation and tumor growth by in vitro cell culture and in vivo xenograft approaches.

Results: The key members of both GDNF/RET and HH/GLI pathways are expressed in NB cell lines to different extents. Knockdown of RET in NB cells significantly attenuates the activity of HH signaling, whereas overexpression of RET robustly enhances the output of transcriptional activation by HH. Likewise, activation of RET by GDNF induces HH signaling, whereas knockdown of RET attenuates both basal and GDNF-induced activities of HH signaling. Moreover, protein kinase B lies on the downstream of GDNF/RET signaling module to inhibit the GSK3β, resulting in activation of HH signaling. Furthermore, either knockdown of RET by shRNA or inhibition of HH pathway by cyclopamine attenuates not only basal but also GDNF-induced proliferation of SH-SY5Y cells, and knockdown of either RET or smoothened in SH-SY5Y cell xenografts significantly attenuated the tumor growth. Finally, inhibition of HH signaling by GLI1 and GLI2 inhibitor, Gant61, reduces not only basal but also RET-induced proliferation of SH-SY5Y cells and outgrowth of xenografts.

Conclusion: GDNF/RET/AKT/GSK3β signaling module activates HH pathway to stimulate NB cells proliferation and tumor outgrowth.

General Significance: Targeting HH pathway is a rational approach for therapeutic intervention of NB with high RET expression.
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http://dx.doi.org/10.1016/j.bbagen.2016.06.017DOI Listing
September 2016

Ginkgolide B functions as a determinant constituent of Ginkgolides in alleviating lipopolysaccharide-induced lung injury.

Biomed Pharmacother 2016 Jul 11;81:71-78. Epub 2016 Apr 11.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou City 310058, China. Electronic address:

Ginkgolides are the major bioactive components of Ginkgo biloba extracts, however, the exact constituents of Ginkgolides contributing to their pharmacological effects remain unknown. Herein, we have determined the anti-inflammatory effects of Ginkgolide B (GB) and Ginkgolides mixture (GM) at equivalent dosages against lipopolysaccharide (LPS)-induced inflammation. RAW 264.7 cell culture model and mouse model of LPS-induced lung injury were used to evaluate in vitro and in vivo effects of GB and GM, respectively. In RAW 264.7 cells, GB and GM at equivalent dosages exhibit an identical capacity to attenuate LPS-induced inducible nitric oxide synthase mRNA and protein expression and subsequent NO production. Likewise, GB and GM possess almost the same potency in attenuating LPS-induced expression and activation of nuclear factor kappa B (p65) and subsequent increases in tumor necrosis factor-α mRNA levels. In LPS-induced pulmonary injury, GB and GM at the equivalent dosages have equal efficiency in attenuating the accumulation of inflammatory cells, including neutrophils, lymphocytes, and macrophages, and in improving the histological damage of lungs. Moreover, GB and GM at equivalent dosages decrease the exudation of plasma protein to the same degree, whereas GM is superior to GB in alleviating myeloperoxidase activities. Finally, though GB and GM at equivalent dosages appear to reduce LPS-induced IL-1β mRNA and protein levels and IL-10 protein levels to the same degree, GM is more potent than GB to attenuate the IL-10 mRNA levels. Taken together, this study demonstrates that GB functions as the determinant constituent of Ginkgolides in alleviating LPS-induced lung injury.
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http://dx.doi.org/10.1016/j.biopha.2016.03.048DOI Listing
July 2016

Phosphodiesterase 5/protein kinase G signal governs stemness of prostate cancer stem cells through Hippo pathway.

Cancer Lett 2016 08 11;378(1):38-50. Epub 2016 May 11.

Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou, China; Program of Molecular and Cellular Biology, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address:

Cancer stem cells (CSC) are critical for initiation, metastasis, and relapse of cancers, however, the underlying mechanism governing stemness of CSC remains unknown. Herein, we have investigated the roles of phosphodiesterase 5 (PDE5) in stemness of prostate cancer cells. Both PDE5 and WW domain-containing transcription regulator protein-1 (TAZ), a core effector of Hippo pathway, are highly expressed in the PC3-derived cancer stem cells (PCSC). Either TAZ knockdown or inhibition of PDE5 activity attenuated colony formation, altered expression patterns of stem cell markers, and enhanced cisplatin cytotoxicity, resulting in attenuation of stemness in PCSC. In addition, inhibition of PDE5 activity by its specific inhibitors activates cGMP-dependent protein kinase G (PKG), which in turn induces MST/LATS kinases, resulting in cytosolic degradation of TAZ and activation of Hippo pathway. Accordingly, knockdown of TAZ almost completely abolished PDE5 inhibitor-induced attenuation in stemness in cultured PCSC, whereas knockdown of TAZ not only abolished PDE5 inhibitor-induced attenuation in stemness but also facilitated PDE5 inhibitor-induced trans-differentiation in PCSC xenografts. Together, the present study has uncovered that PDE/cGMP/PKG signal targets to Hippo/TAZ pathway in maintaining stemness of PCSC, and suggested that PDE5 inhibitors in combination with chemotherapeutic agents could effectively prevent initiation, metastasis, and relapse of prostate cancer.
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http://dx.doi.org/10.1016/j.canlet.2016.05.010DOI Listing
August 2016