title: Complex regulation of the cyclin-dependent kinase inhibitor p27kip1 in thyroid cancer cells by the PI3K/AKT pathway: regulation of p27kip1 expression and localization.
abstract: Functional inactivation of the tumor suppressor p27(kip1) in human cancer occurs either through loss of expression or through phosphorylation-dependent cytoplasmic sequestration. Here we demonstrate that dysregulation of the PI3K/AKT pathway is important in thyroid carcinogenesis and that p27(kip1) is a key target of the growth-regulatory activity exerted by this pathway in thyroid cancer cells. Using specific PI3K inhibitors (LY294002, wortmannin, and PTEN) and a dominant active AKT construct (myrAKT), we demonstrated that the PI3K/AKT pathway controlled thyroid cell proliferation by regulating the expression and subcellular localization of p27. Results obtained with phospho-specific antibodies and with transfection of nonphosphorylable p27(kip1) mutant constructs demonstrated that PI3K/AKT-dependent regulation of p27(kip1) mislocalization in thyroid cancer cells occurred via phosphorylation of p27(kip1) at T157 and T198 (but not at S10 or T187). Finally, we evaluated whether these results were applicable to human tumors. Analysis of 100 thyroid carcinomas indicated that p27(kip1) phosphorylation at T157/T198 and cytoplasmic mislocalization were preferentially associated with activation of the PI3K/AKT pathway. Thus the PI3/AKT pathway and its effector p27(kip1) play major roles in thyroid carcinogenesis.
authors.affiliation: Dipartimento di Biologia e Patologia Cellulare e Molecolare L. Califano, Università di Napoli Federico II, via S. Pansini 5, 80131 Napoli, Italy.
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Motti
authors.forename: Daniela
authors.initials: D
authors.lastname: Califano
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Troncone
authors.forename: Carmela
authors.initials: C
authors.lastname: De Marco
authors.forename: Ilenia
authors.initials: I
authors.lastname: Migliaccio
authors.forename: Emiliano
authors.initials: E
authors.lastname: Palmieri
authors.forename: Luciano
authors.initials: L
authors.lastname: Pezzullo
authors.forename: Lucio
authors.initials: L
authors.lastname: Palombini
authors.forename: Alfredo
authors.initials: A
authors.lastname: Fusco
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Viglietto
mesh_terms: D000730:Androstadienes / Q000494:pharmacology; D015153:Blotting, Western; D001973:Bromodeoxyuridine / Q000494:pharmacology; D018797:Cell Cycle Proteins / Q000096:biosynthesis* / Q000378:metabolism; D045744:Cell Line, Tumor; D002867:Chromones / Q000494:pharmacology; D050760:Cyclin-Dependent Kinase Inhibitor p27; D003593:Cytoplasm / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004789:Enzyme Activation; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008856:Microscopy, Fluorescence; D009025:Morpholines / Q000494:pharmacology; D051059:PTEN Phosphohydrolase; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D020133:Reverse Transcriptase Polymerase Chain Reaction; D044786:S-Phase Kinase-Associated Proteins / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis* / Q000378:metabolism; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D001973:Bromodeoxyuridine; D018797:Cell Cycle Proteins; D002867:Chromones; D050760:Cyclin-Dependent Kinase Inhibitor p27; D009025:Morpholines; D051059:PTEN Phosphohydrolase; D019869:Phosphatidylinositol 3-Kinases; D010744:Phosphoric Monoester Hydrolases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D044786:S-Phase Kinase-Associated Proteins; D025521:Tumor Suppressor Proteins; D000077191:Wortmannin; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C494918:AKT1 protein, human; C494929:PTEN protein, human
references.citation: J Natl Cancer Inst. 2003 Apr 16;95(8):625-7
references.pmid: 12697856
references.citation: EMBO J. 1999 Mar 1;18(5):1223-34
references.pmid: 10064589
references.citation: Eur J Endocrinol. 1999 Jan;140(1):94-103
references.pmid: 10037258
references.citation: J Cell Physiol. 2000 Apr;183(1):18-27
references.pmid: 10699962
references.citation: Genes Dev. 1994 Jan;8(1):9-22
references.pmid: 8288131
references.citation: Oncogene. 2000 Jun 29;19(28):3146-55
references.pmid: 10918569
references.citation: Thyroid. 2001 Apr;11(4):339-51
references.pmid: 11349832
references.citation: J Biol Chem. 2000 Dec 15;275(50):39223-30
references.pmid: 11010972
references.citation: Biochim Biophys Acta. 2002 Mar 14;1602(1):73-87
references.pmid: 11960696
references.citation: EMBO J. 2001 Dec 3;20(23):6672-82
references.pmid: 11726503
references.citation: Cancer Res. 2004 Jun 1;64(11):3823-9
references.pmid: 15172989
references.citation: J Med Genet. 2004 Mar;41(3):161-70
references.pmid: 14985374
references.citation: Biochem J. 2000 Jun 1;348 Pt 2:351-8
references.pmid: 10816429
references.citation: Nat Med. 2002 Oct;8(10):1076-8
references.pmid: 12357238
references.citation: Am J Pathol. 2000 May;156(5):1693-700
references.pmid: 10793080
references.citation: Int J Oncol. 1998 Mar;12(3):701-10
references.pmid: 9472113
references.citation: Science. 1995 Aug 4;269(5224):682-5
references.pmid: 7624798
references.citation: Nat Med. 1997 Feb;3(2):227-30
references.pmid: 9018244
references.citation: J Clin Invest. 1999 Oct;104(7):865-74
references.pmid: 10510327
references.citation: Cell Cycle. 2002 Nov-Dec;1(6):391-3
references.pmid: 12548011
references.citation: J Immunol. 2004 May 1;172(9):5522-7
references.pmid: 15100294
references.citation: Cell Cycle. 2004 Aug;3(8):1074-80
references.pmid: 15280662
references.citation: Mol Cell Biol. 2000 Aug;20(15):5690-9
references.pmid: 10891505
references.citation: Cancer Res. 1998 Apr 15;58(8):1730-5
references.pmid: 9563491
references.citation: Genes Dev. 1999 Jun 15;13(12):1501-12
references.pmid: 10385618
references.citation: J Cell Physiol. 2000 Apr;183(1):10-7
references.pmid: 10699961
references.citation: Nature. 2001 May 17;411(6835):355-65
references.pmid: 11357143
references.citation: Mol Endocrinol. 2002 May;16(5):903-11
references.pmid: 11981026
references.citation: Biochem Biophys Res Commun. 2000 Jul 21;274(1):37-42
references.pmid: 10903892
references.citation: Genes Dev. 1997 Jun 1;11(11):1464-78
references.pmid: 9192873
references.citation: Nature. 2000 Apr 13;404(6779):782-7
references.pmid: 10783894
references.citation: Cell Cycle. 2002 Nov-Dec;1(6):394-400
references.pmid: 12548012
references.citation: Oncogene. 2003 Jul 17;22(29):4578-80
references.pmid: 12881714
references.citation: J Biol Chem. 2002 Aug 9;277(32):28706-13
references.pmid: 12042314
references.citation: Genes Dev. 1999 May 1;13(9):1181-9
references.pmid: 10323868
references.citation: Endocr Pathol. 2002 Spring;13(1):3-16
references.pmid: 12114746
references.citation: Cancer Res. 1997 Aug 15;57(16):3381-5
references.pmid: 9270000
references.citation: Nat Med. 2002 Oct;8(10):1145-52
references.pmid: 12244301
references.citation: Cancer Res. 1999 Aug 1;59(15):3790-4
references.pmid: 10446997
references.citation: Oncogene. 1999 Nov 4;18(46):6241-51
references.pmid: 10597222
references.citation: EMBO J. 2002 Jul 1;21(13):3390-401
references.pmid: 12093740
references.citation: Nat Cell Biol. 1999 Aug;1(4):193-9
references.pmid: 10559916
references.citation: Oncogene. 1992 Dec;7(12):2549-53
references.pmid: 1334253
references.citation: Endocr Rev. 2001 Oct;22(5):631-56
references.pmid: 11588145
references.citation: J Clin Endocrinol Metab. 2003 Sep;88(9):4393-7
references.pmid: 12970315
references.citation: Nat Med. 2002 Oct;8(10):1136-44
references.pmid: 12244303
references.citation: Curr Opin Cell Biol. 1998 Apr;10(2):262-7
references.pmid: 9561851
references.citation: Cancer Res. 1997 Nov 1;57(21):4710-3
references.pmid: 9354427
references.citation: Genes Chromosomes Cancer. 1998 Nov;23(3):239-43
references.pmid: 9790504
references.citation: J Clin Endocrinol Metab. 2003 May;88(5):2318-26
references.pmid: 12727991
references.citation: Science. 1991 Oct 11;254(5029):274-7
references.pmid: 1833819
references.citation: Mol Cell Biol. 2000 Dec;20(24):9138-48
references.pmid: 11094066
references.citation: Cancer Res. 1998 Jan 1;58(1):114-22
references.pmid: 9426067
references.citation: J Immunol. 2002 May 15;168(10):5024-31
references.pmid: 11994454
references.citation: Cancer Res. 2001 Aug 15;61(16):6105-11
references.pmid: 11507060
references.citation: EMBO J. 1997 Sep 1;16(17):5334-44
references.pmid: 9311993
references.citation: Nat Med. 1997 Feb;3(2):231-4
references.pmid: 9018245
references.citation: EMBO J. 2004 May 5;23(9):1934-42
references.pmid: 15057270
references.citation: Science. 1996 Dec 6;274(5293):1672-7
references.pmid: 8939849
references.citation: Nat Med. 2002 Oct;8(10):1153-60
references.pmid: 12244302
references.citation: Genes Dev. 1998 Nov 15;12(22):3499-511
references.pmid: 9832503