Expression and responsiveness of P2Y2 receptors in human endometrial cancer cell lines.
In single endometrial carcinoma HEC-1A and Ishikawa cells, ATP induced a rapid and extracellular Ca2+-independent rise in cytosolic Ca2+ concentration ([Ca2+]i) in a dose-dependent manner, with an ED50 of about 10 microM. The spike phase was followed by a sustained plateau phase that was dependent on Ca2+ influx through voltage-insensitive Ca2+ channels, whose gating was controlled by a capacitative Ca2+ entry mechanism. ADP was less potent in raising the cystolic Ca2+ concentration, and AMP and adenosine were ineffective. The order of agonist potency for this receptor was ATP = UTP > ATP-gamma-S >> ADP. Several other agonists, including beta,gamma-methylene-ATP, 2-MeS-ATP, and BzATP were ineffective. This ligand-selective profile indicates the expression of the P2Y2R subtype in endometrial cells. Accordingly, reverse transcription-PCR using P2Y2 primers amplified the expected transcript from both cell lines. The coupling of these receptors to phospholipase C was confirmed by the ability of ATP to increase inositol 1,4,5-trisphosphate and diacylglycerol productions. These receptors are also coupled to the phospholipase D-1 pathway, leading to accumulation of phosphatidic acid. Activation of P2Y2 receptors by a slowly degradable ATP analog, ATP-gamma-S, was associated with a significant suppression of cell proliferation without affecting the cellular apoptosis. These results indicate that P2Y2 receptors may participate in control of the cell cycle of endometrial carcinoma cells.
Katzur
A C
AC
Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-4510, USA.
Koshimizu
T
T
Tomić
M
M
Schultze-Mosgau
A
A
Ortmann
O
O
Stojilkovic
S S
SS
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D017209:Apoptosis; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D015220:Calcium Channels / Q000502:physiology; D002455:Cell Division; D004075:Diglycerides / Q000096:biosynthesis; D016889:Endometrial Neoplasms / Q000378:metabolism*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis; D015640:Ion Channel Gating; D010712:Phosphatidic Acids / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D058473:Receptors, Purinergic P2Y2; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism; D014544:Uridine Triphosphate / Q000494:pharmacology
D015220:Calcium Channels; D004075:Diglycerides; C546385:P2RY2 protein, human; D010712:Phosphatidic Acids; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; D000244:Adenosine Diphosphate; D015544:Inositol 1,4,5-Trisphosphate; D000255:Adenosine Triphosphate; D010738:Type C Phospholipases; D002118:Calcium; D014544:Uridine Triphosphate