title: Adenosine uptake is the major effector of extracellular ATP toxicity in human cervical cancer cells.
abstract: In cervical cancer, HPV infection and disruption of mechanisms involving cell growth, differentiation, and apoptosis are strictly linked with tumor progression and invasion. Tumor microenvironment is ATP and adenosine rich, suggesting a role for purinergic signaling in cancer cell growth and death. Here we investigate the effect of extracellular ATP on human cervical cancer cells. We find that extracellular ATP itself has a small cytotoxic effect, whereas adenosine formed from ATP degradation by ectonucleotidases is the main factor responsible for apoptosis induction. The level of P2 × 7 receptor seemed to define the main cytotoxic mechanism triggered by ATP, since ATP itself eliminated a small subpopulation of cells that express high P2 × 7 levels, probably through its activation. Corroborating these data, blockage or knockdown of P2 × 7 only slightly reduced ATP cytotoxicity. On the other hand, cell viability was almost totally recovered with dipyridamole, an adenosine transporter inhibitor. Moreover, ATP-induced apoptosis and signaling-p53 increase, AMPK activation, and PARP cleavage-as well as autophagy induction were also inhibited by dipyridamole. In addition, inhibition of adenosine conversion into AMP also blocked cell death, indicating that metabolization of intracellular adenosine originating from extracellular ATP is responsible for the main effects of the latter in human cervical cancer cells.
authors.affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.
authors.forename: Paola de Andrade
authors.initials: Pde A
authors.lastname: Mello
authors.affiliation: Department of Biophysics and Center of Biotechnology, Federal University of Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil.
authors.forename: Eduardo Cremonese
authors.initials: EC
authors.lastname: Filippi-Chiela
authors.affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.
authors.forename: Jéssica
authors.initials: J
authors.lastname: Nascimento
authors.affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Beckenkamp
authors.affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.
authors.forename: Danielle Bertodo
authors.initials: DB
authors.lastname: Santana
authors.affiliation: Department of Biophysics and Center of Biotechnology, Federal University of Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil.
authors.forename: Franciele
authors.initials: F
authors.lastname: Kipper
authors.affiliation: Department of Morphological Science and Department of Biochemistry, Institute of Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS 90000-000, Brazil.
authors.forename: Emerson André
authors.initials: EA
authors.lastname: Casali
authors.affiliation: Federal Institute of Education, Science and Technology, Porto Alegre, RS 90035-007, Brazil.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Nejar Bruno
authors.affiliation: International Center for Genetic Engineering and Biotechnology, Cancer Genomics Group, Cape Town 7925, South Africa.
authors.forename: Juliano Domiraci
authors.initials: JD
authors.lastname: Paccez
authors.affiliation: International Center for Genetic Engineering and Biotechnology, Cancer Genomics Group, Cape Town 7925, South Africa.
authors.forename: Luiz Fernando
authors.initials: LF
authors.lastname: Zerbini
authors.affiliation: Laboratory of Cell Biology, Federal University of Health Sciences of Porto Alegre, Porto Alegre, RS 90050-170, Brazil.
authors.forename: Marcia Rosângela
authors.initials: MR
authors.lastname: Wink
authors.affiliation: Department of Biophysics and Center of Biotechnology, Federal University of Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil.
authors.forename: Guido
authors.initials: G
authors.lastname: Lenz
authors.affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil andreia.buffon@ufrgs.br.
authors.forename: Andréia
authors.initials: A
authors.lastname: Buffon
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism; D000241:Adenosine / Q000378:metabolism*; D000249:Adenosine Monophosphate / Q000096:biosynthesis*; D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004176:Dipyridamole / Q000494:pharmacology; D005260:Female; D006367:HeLa Cells; D006801:Humans; D033703:Nucleoside Transport Proteins / Q000037:antagonists & inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis; D034741:RNA, Small Interfering; D058486:Receptors, Purinergic P2X7 / Q000235:genetics / Q000378:metabolism; D059016:Tumor Microenvironment; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy*
chemical_list: D033703:Nucleoside Transport Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D058486:Receptors, Purinergic P2X7; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; C444719:adenosine transporter; D000249:Adenosine Monophosphate; D004176:Dipyridamole; D000255:Adenosine Triphosphate; D011065:Poly(ADP-ribose) Polymerases; D055372:AMP-Activated Protein Kinases; D000241:Adenosine
references.citation: Curr Opin Cell Biol. 2010 Apr;22(2):124-31
references.pmid: 20034776
references.citation: PLoS One. 2008 Jul 09;3(7):e2599
references.pmid: 18612415
references.citation: Mol Cell. 2011 Oct 21;44(2):279-89
references.pmid: 22017874
references.citation: J Virol. 1998 Nov;72(11):8463-71
references.pmid: 9765382
references.citation: Methods Enzymol. 2009;453:273-86
references.pmid: 19216911
references.citation: CA Cancer J Clin. 2011 Mar-Apr;61(2):69-90
references.pmid: 21296855
references.citation: Clin Chem. 2000 Apr;46(4):537-42
references.pmid: 10759478
references.citation: J Biol Chem. 2007 Aug 17;282(33):24131-45
references.pmid: 17580304
references.citation: Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13132-7
references.pmid: 16916931
references.citation: Biochem Pharmacol. 2004 May 15;67(10):2005-11
references.pmid: 15130776
references.citation: Am J Physiol Cell Physiol. 2004 Nov;287(5):C1349-58
references.pmid: 15269006
references.citation: J Biomed Biotechnol. 2012;2012:473712
references.pmid: 23133312
references.citation: Purinergic Signal. 2009 Sep;5(3):351-68
references.pmid: 19399640
references.citation: Cell Mol Neurobiol. 2011 Nov;31(8):1171-86
references.pmid: 21643997
references.citation: J Cell Sci. 2004 Jun 1;117(Pt 13):2805-12
references.pmid: 15169837
references.citation: Cancer Res. 2012 Nov 1;72(21):5441-7
references.pmid: 23090120
references.citation: J Natl Cancer Inst. 2011 Mar 2;103(5):368-83
references.pmid: 21282563
references.citation: Purinergic Signal. 2013 Dec;9(4):491-540
references.pmid: 23797685
references.citation: Mol Cell Biochem. 2003 May;247(1-2):111-9
references.pmid: 12841638
references.citation: Biochem Cell Biol. 2014 Apr;92(2):95-104
references.pmid: 24697693
references.citation: Annu Rev Genet. 2009;43:67-93
references.pmid: 19653858
references.citation: Nucleosides Nucleotides Nucleic Acids. 2008 Jun;27(6):816-20
references.pmid: 18600545
references.citation: Br J Pharmacol. 2003 Nov;140(6):1009-18
references.pmid: 14530217
references.citation: PLoS One. 2013;8(4):e60184
references.pmid: 23565201
references.citation: Leuk Lymphoma. 2011 Jun;52 Suppl 2:43-5
references.pmid: 21463108
references.citation: Pflugers Arch. 2004 Feb;447(5):735-43
references.pmid: 12838422
references.citation: Methods Enzymol. 1983;91:95-119
references.pmid: 6855607
references.citation: Neoplasia. 2011 Mar;13(3):206-16
references.pmid: 21390184
references.citation: J Invest Dermatol. 2012 Mar;132(3 Pt 1):526-46
references.pmid: 22158558
references.citation: Autophagy. 2008 Feb;4(2):151-75
references.pmid: 18188003
references.citation: J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Jan 25;784(1):101-9
references.pmid: 12504187
references.citation: J Cell Biochem. 2010 Apr 1;109(5):983-91
references.pmid: 20069573
references.citation: Nat Protoc. 2006;1(5):2315-9
references.pmid: 17406473
references.citation: Cell Physiol Biochem. 2012;30(1):61-74
references.pmid: 22759956
references.citation: Cancer Chemother Pharmacol. 2008 Jul;62(2):215-26
references.pmid: 17896107
references.citation: Neurotoxicology. 2006 Jul;27(4):458-67
references.pmid: 16469385
references.citation: Eur J Obstet Gynecol Reprod Biol. 2006 Jul;127(1):110-4
references.pmid: 16815472
references.citation: Cancer Res. 2003 May 1;63(9):2206-15
references.pmid: 12727841
references.citation: J Physiol. 2006 Jul 1;574(Pt 1):7-15
references.pmid: 16644800
references.citation: Cancer Lett. 2012 Aug 1;321(1):65-72
references.pmid: 22388174