ATP stimulates the proliferation of MCF-7 cells through the PI3K/Akt signaling pathway.
We studied the modulation of the PI3K/Akt signaling pathway by ATP in MCF-7 cells. Western blot analysis showed that ATP stimulated the phosphorylation of Akt in a dose- and time-dependent manner. Akt phosphorylation in response to nucleotides followed the potency order ATP=UTP=ATPgammaS>>ADP=UDP>ADPbetaS=adenosine, suggesting participation of P2Y(2/4) receptors. Inhibitors of PI3K, PLC, PKC and Src or Src antisense oligonucleotides prevented ATP-induced phosphorylation of Akt. Incubation of cells with 2-APB or in a nominally Ca(2+)-free medium plus EGTA showed that Akt phosphorylation by ATP depends on intracellular calcium release but is independent of calcium influx. The PI3K inhibitor was not effective in reducing MAPKs phosphorylation by ATP. ATP and UTP stimulated MCF-7 cell proliferation, effect that was inhibited by PI3K, PLC, PKC, Src and MAPKs inhibitors. These findings suggest that ATP modulation of P2Y(2/4) receptors increases MCF-7 cell proliferation by activation of the PI3K/Akt signaling pathway through PLC/IP(3)/Ca(2+), PKC and Src.
Bilbao
Paola Scodelaro
PS
Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, (B8000ICN) Bahía Blanca, Argentina.
Santillán
Graciela
G
Boland
Ricardo
R
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D020013:Calcium Signaling; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D005260:Female; D016391:Genes, src; D006801:Humans; D020935:MAP Kinase Signaling System; D009711:Nucleotides / Q000494:pharmacology; D020319:Oligodeoxyribonucleotides, Antisense / Q000235:genetics; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000378:metabolism; D058473:Receptors, Purinergic P2Y2; D015398:Signal Transduction / Q000187:drug effects
D009711:Nucleotides; D020319:Oligodeoxyribonucleotides, Antisense; C546385:P2RY2 protein, human; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; C104749:purinoceptor P2Y4; D000255:Adenosine Triphosphate; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D011493:Protein Kinase C