{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T11:03:49Z","timestamp":1792839829614,"version":"4.5.0"},"reference-count":34,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"5","license":[{"start":{"date-parts":[[2015,9,1]],"date-time":"2015-09-01T00:00:00Z","timestamp":1441065600000},"content-version":"tdm","delay-in-days":1949,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2010,5]]},"abstract":"<jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      <jats:bold>Polycystic liver disease may complicate autosomal dominant polycystic kidney disease (ADPKD), a disease caused by mutations in polycystins, which are proteins that regulate signaling, morphogenesis, and differentiation in epithelial cells. The cystic biliary epithelium [liver cystic epithelium (LCE)] secretes vascular endothelial growth factor (VEGF), which promotes liver cyst growth via autocrine and paracrine mechanisms. The expression of insulin-like growth factor 1 (IGF1), insulin-like growth factor 1 receptor (IGF1R), and phosphorylated mammalian target of rapamycin (p-mTOR) and the protein kinase A (PKA)\u2013dependent phosphorylation of extracellular signal-regulated kinase 1\/2 (ERK1\/2) are also up-regulated in LCE. We have hypothesized that mammalian target of rapamycin (mTOR) represents a common pathway for the regulation of hypoxia-inducible factor 1 alpha (HIF1\u03b1)\u2013dependent VEGF secretion by IGF1 and ERK1\/2. Conditional polycystin-2\u2013knockout (Pkd2KO) mice were used for in vivo studies and to isolate cystic cholangiocytes [liver cystic epithelial cells (LCECs)]. The expression of p-mTOR, VEGF, cleaved caspase 3 (CC3), proliferating cell nuclear antigen (PCNA), IGF1, IGF1R, phosphorylated extracellular signal-regulated kinase, p-P70S6K, HIF1\u03b1, and VEGF in LCE, LCECs, and wild-type cholangiocytes was studied with immunohistochemistry, western blotting, or enzyme-linked immunosorbent assays. The cystic area was measured by computer-assisted morphometry of pancytokeratin-stained sections. Cell proliferation in vitro was studied with 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2<\/jats:bold>\n                      <jats:bold>H<\/jats:bold>\n                      <jats:bold>-tetrazolium and bromodeoxyuridine assays. The treatment of Pkd2KO mice with the mTOR inhibitor rapamycin significantly reduced the liver cyst area, liver\/body weight ratio, pericystic microvascular density, and PCNA expression while increasing expression of CC3. Rapamycin inhibited IGF1-stimulated HIF1\u03b1 accumulation and VEGF secretion in LCECs. IGF1-stimulated LCEC proliferation was inhibited by rapamycin and SU5416 (a vascular endothelial growth factor receptor 2 inhibitor). Phosphorylation of the mTOR-dependent kinase P70S6K was significantly reduced by PKA inhibitor 14-22 amide and by the mitogen signal-regulated kinase inhibitor U1026.<\/jats:bold>\n                      <jats:bold>Conclusion:<\/jats:bold>\n                      <jats:bold>These data demonstrate that PKA-dependent up-regulation of mTOR has a central role in the proliferative, antiapoptotic, and pro-angiogenic effects of IGF1 and VEGF in polycystin-2\u2013defective mice. This study also highlights a mechanistic link between PKA, ERK, mTOR, and HIF1\u03b1-mediated VEGF secretion and provides a proof of concept for the potential use of mTOR inhibitors in ADPKD and conditions with aberrant cholangiocyte proliferation. (Hepatology 2010.)<\/jats:bold>\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/hep.23511","type":"journal-article","created":{"date-parts":[[2009,12,23]],"date-time":"2009-12-23T09:18:15Z","timestamp":1261559895000},"page":"1778-1788","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":81,"title":["Mammalian Target of Rapamycin Regulates Vascular Endothelial Growth Factor\u2013Dependent Liver Cyst Growth in Polycystin-2\u2013Defective Mice"],"prefix":"10.1097","volume":"51","author":[{"given":"Carlo","family":"Spirli","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Okolicsanyi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Romina","family":"Fiorotto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luca","family":"Fabris","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Massimiliano","family":"Cadamuro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Lecchi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Tian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Somlo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Strazzabosco","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"R1-35-20250312","doi-asserted-by":"crossref","first-page":"64","DOI":"10.2215\/CJN.00080605","article-title":"Magnetic resonance imaging evaluation of hepatic cysts in early autosomaldominant polycystic kidney disease: the Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease cohort.","volume":"1","author":"Bae","year":"2006","journal-title":"Clin J Am Soc Nephrol"},{"key":"R2-35-20250312","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1038\/ncpneph0070","article-title":"Mechanisms of disease: autosomal dominant and recessive polycystic kidney diseases.","volume":"2","author":"Torres","year":"2006","journal-title":"Nat Clin Pract Nephrol"},{"key":"R3-35-20250312","doi-asserted-by":"crossref","first-page":"6454","DOI":"10.1073\/pnas.0610324104","article-title":"Regulation of ryanodine receptordependent calcium signaling by polycystin2.","volume":"104","author":"Anyatonwu","year":"2007","journal-title":"Proc Natl Acad Sci U S A"},{"key":"R4-35-20250312","doi-asserted-by":"crossref","first-page":"41298","DOI":"10.1074\/jbc.M510082200","article-title":"Polycystin 2 interacts with type I inositol 1,4,5trisphosphate receptor to modulate intracellular Ca2 signaling.","volume":"280","author":"Li","year":"2005","journal-title":"J Biol Chem"},{"key":"R5-35-20250312","doi-asserted-by":"crossref","first-page":"321","DOI":"10.2353\/ajpath.2008.070293","article-title":"Morphological and functional features of hepatic cyst epithelium in autosomal dominant polycystic kidney disease.","volume":"172","author":"Alvaro","year":"2008","journal-title":"Am J Pathol"},{"key":"R6-35-20250312","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1002\/hep.21143","article-title":"Effects of angiogenic factor overexpression by human and rodent cholangiocytes in polycystic liver diseases.","volume":"43","author":"Fabris","year":"2006","journal-title":"HEPATOLOGY"},{"key":"R8-35-20250312","first-page":"372","article-title":"Synergy between PI3KAkt and RafMEKERK pathways in IGF1R mediated cell cycle progression and prevention of apoptosis in hematopoietic cells.","volume":"3","author":"Shelton","year":"2004","journal-title":"Cell Cycle"},{"key":"R9-35-20250312","doi-asserted-by":"crossref","first-page":"2255","DOI":"10.1038\/sj.onc.1210019","article-title":"AKT activity regulates the ability of mTOR inhibitors to prevent angiogenesis and VEGF expression in multiple myeloma cells.","volume":"26","author":"Frost","year":"2007","journal-title":"Oncogene"},{"key":"R10-35-20250312","doi-asserted-by":"crossref","first-page":"1304","DOI":"10.1210\/me.2004-0239","article-title":"Regulation of hypoxiainducible factor (HIF)1 activity and expression of HIF hydroxylases in response to insulinlike growth factor I.","volume":"19","author":"Treins","year":"2005","journal-title":"Mol Endocrinol"},{"key":"R11-35-20250312","doi-asserted-by":"crossref","first-page":"5466","DOI":"10.1073\/pnas.0509694103","article-title":"The mTOR pathway is regulated by polycystin1, and its inhibition reverses renal cystogenesis in polycystic kidney disease.","volume":"103","author":"Shillingford","year":"2006","journal-title":"Proc Natl Acad Sci U S A"},{"key":"R12-35-20250312","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1681\/ASN.2004080660","article-title":"Rapamycin markedly slows disease progression in a rat model of polycystic kidney disease.","volume":"16","author":"Tao","year":"2005","journal-title":"J Am Soc Nephrol"},{"key":"R13-35-20250312","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1159\/000104818","article-title":"Everolimus retards cyst growth and preserves kidney function in a rodent model for polycystic kidney disease.","volume":"30","author":"Wu","year":"2007","journal-title":"Kidney Blood Press Res"},{"key":"R14-35-20250312","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1681\/ASN.2007050626","article-title":"Sirolimus reduces polycystic liver volume in ADPKD patients.","volume":"19","author":"Qian","year":"2008","journal-title":"J Am Soc Nephrol"},{"key":"R15-35-20250312","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1038\/nm0202-128","article-title":"Rapamycin inhibits primary and metastatic tumor growth by antiangiogenesis: involvement of vascular endothelial growth factor.","volume":"8","author":"Guba","year":"2002","journal-title":"Nat Med"},{"key":"R16-35-20250312","doi-asserted-by":"crossref","first-page":"6680","DOI":"10.1038\/sj.onc.1204091","article-title":"The rapamycinsensitive signal transduction pathway as a target for cancer therapy.","volume":"19","author":"Hidalgo","year":"2000","journal-title":"Oncogene"},{"key":"R17-35-20250312","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1002\/gene.10021","article-title":"A Cre recombinase transgene with mosaic, widespread tamoxifeninducible action.","volume":"32","author":"Guo","year":"2002","journal-title":"Genesis"},{"key":"R18-35-20250312","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1111\/j.1365-2613.2007.00533.x","article-title":"Vascular endothelial growth factor (VEGF), VEGF receptors expression and microvascular density in benign and malignant thyroid diseases.","volume":"88","author":"Jebreel","year":"2007","journal-title":"Int J Exp Pathol"},{"key":"R19-35-20250312","doi-asserted-by":"crossref","first-page":"2359","DOI":"10.1128\/MCB.01259-08","article-title":"Polycystin1 regulates extracellular signalregulated kinasedependent phosphorylation of tuberin to control cell size through mTOR and its downstream effectors S6K and 4EBP1.","volume":"29","author":"Distefano","year":"2009","journal-title":"Mol Cell Biol"},{"key":"R20-35-20250312","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1016\/j.cell.2006.01.016","article-title":"TOR signaling in growth and metabolism.","volume":"124","author":"Wullschleger","year":"2006","journal-title":"Cell"},{"key":"R21-35-20250312","doi-asserted-by":"crossref","first-page":"13489","DOI":"10.1073\/pnas.0405659101","article-title":"Tumorpromoting phorbol esters and activated Ras inactivate the tuberous sclerosis tumor suppressor complex via p90 ribosomal S6 kinase.","volume":"101","author":"Roux","year":"2004","journal-title":"Proc Natl Acad Sci U S A"},{"key":"R22-35-20250312","doi-asserted-by":"crossref","first-page":"4258","DOI":"10.2741\/3003","article-title":"The RSK factors of activating the RasMAPK signaling cascade.","volume":"13","author":"Carriere","year":"2008","journal-title":"Front Biosci"},{"key":"R23-35-20250312","doi-asserted-by":"crossref","first-page":"14056","DOI":"10.1074\/jbc.M700906200","article-title":"RASERK signaling promotes sitespecific ribosomal protein S6 phosphorylation via RSK and stimulates capdependent translation.","volume":"282","author":"Roux","year":"2007","journal-title":"J Biol Chem"},{"key":"R24-35-20250312","doi-asserted-by":"crossref","first-page":"2128","DOI":"10.1007\/s10620-008-0605-3","article-title":"Antitumoral activity of rapamycin mediated through inhibition of HIF1alpha and VEGF in hepatocellular carcinoma.","volume":"54","author":"Wang","year":"2009","journal-title":"Dig Dis Sci"},{"key":"R25-35-20250312","doi-asserted-by":"crossref","first-page":"598","DOI":"10.1093\/ndt\/gfi181","article-title":"Inhibition of mTOR with sirolimus slows disease progression in Han:SPRD rats with autosomal dominant polycystic kidney disease (ADPKD).","volume":"21","author":"Wahl","year":"2006","journal-title":"Nephrol Dial Transplant"},{"key":"R26-35-20250312","doi-asserted-by":"crossref","first-page":"451","DOI":"10.7326\/0003-4819-147-7-200710020-00003","article-title":"Serum and biliary insulinlike growth factor I and vascular endothelial growth factor in determining the cause of obstructive cholestasis.","volume":"147","author":"Alvaro","year":"2007","journal-title":"Ann Intern Med"},{"key":"R27-35-20250312","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1369\/jhc.6R7125.2006","article-title":"Activation of the IGF1 system characterizes cholangiocyte survival during progression of primary biliary cirrhosis.","volume":"55","author":"Onori","year":"2007","journal-title":"J Histochem Cytochem"},{"key":"R28-35-20250312","doi-asserted-by":"crossref","first-page":"875","DOI":"10.1016\/j.jhep.2005.04.011","article-title":"The intrahepatic biliary epithelium is a target of the growth hormoneinsulinlike growth factor 1 axis.","volume":"43","author":"Alvaro","year":"2005","journal-title":"J Hepatol"},{"key":"R29-35-20250312","doi-asserted-by":"crossref","first-page":"185","DOI":"10.2478\/v10042-008-0028-1","article-title":"The effect of tyrosine kinase inhibitors, tyrphostins: AG1024 and SU1498, on autocrine growth of prostate cancer cells (DU145).","volume":"46","author":"Kisielewska","year":"2008","journal-title":"Folia Histochem Cytobiol"},{"key":"R30-35-20250312","doi-asserted-by":"crossref","first-page":"19138","DOI":"10.1073\/pnas.0705964104","article-title":"Cholangiocyte cilia express TRPV4 and detect changes in luminal tonicity inducing bicarbonate secretion.","volume":"104","author":"Gradilone","year":"2007","journal-title":"Proc Natl Acad Sci U S A"},{"key":"R31-35-20250312","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1038\/ncb1850","article-title":"Storeoperated cyclic AMP signalling mediated by STIM1.","volume":"11","author":"Lefkimmiatis","year":"2009","journal-title":"Nat Cell Biol"},{"key":"R32-35-20250312","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1053\/j.gastro.2006.07.003","article-title":"Cholangiocyte cilia detect changes in luminal fluid flow and transmit them into intracellular Ca2 and cAMP signaling.","volume":"131","author":"Masyuk","year":"2006","journal-title":"Gastroenterology"},{"key":"R33-35-20250312","doi-asserted-by":"crossref","first-page":"1983","DOI":"10.1046\/j.1523-1755.2003.00023.x","article-title":"Cyclic AMP activates BRaf and ERK in cyst epithelial cells from autosomaldominant polycystic kidneys.","volume":"63","author":"Yamaguchi","year":"2003","journal-title":"Kidney Int"},{"key":"R34-35-20250312","doi-asserted-by":"crossref","first-page":"S90","DOI":"10.1097\/01.mcg.0000155549.29643.ad","article-title":"Pathophysiology of cholangiopathies.","volume":"39","author":"Strazzabosco","year":"2005","journal-title":"J Clin Gastroenterol"},{"key":"R35-35-20250312","doi-asserted-by":"crossref","first-page":"3537","DOI":"10.3748\/wjg.v12.i22.3537","article-title":"Estrogens and the pathophysiology of the biliary tree.","volume":"12","author":"Alvaro","year":"2006","journal-title":"World J Gastroenterol"}],"container-title":["Hepatology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fhep.23511","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.lww.com\/01515467-201005000-00035","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,12]],"date-time":"2025-03-12T07:13:57Z","timestamp":1741763637000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.lww.com\/01515467-201005000-00035"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5]]},"references-count":34,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2010]]}},"URL":"https:\/\/doi.org\/10.1002\/hep.23511","relation":{},"ISSN":["0270-9139"],"issn-type":[{"value":"0270-9139","type":"print"}],"subject":[],"published":{"date-parts":[[2010,5]]}}}