TY - JOUR
T1 - Role of phospholipase D in agonist-stimulated lysophosphatidic acid synthesis by ovarian cancer cells
AU - Luquain, Céline
AU - Singh, Anurag
AU - Wang, Lixin
AU - Natarajan, Vishwanathan
AU - Morris, Andrew J.
PY - 2003/10
Y1 - 2003/10
N2 - Lysophosphatidic acid (LPA) is a receptor-active lipid mediator with a broad range of biological effects. Ovarian cancer cells synthesize LPA, which promotes their motility, growth, and survival. We show that a murine homolog of a human protein previously reported to hydrolyze LPA is a highly selective detergent-stimulated LPA phosphatase that can be used to detect and quantitate LPA. Use of this protein in novel enzymatic assay demonstrates that SK-OV-3 ovarian cancer cells release physiologically relevant levels of biologically active LPA into the extracellular space. LPA release is markedly increased by nucleotide agonists acting through a P2Y4 purinergic receptor. Promotion of LPA formation by nucleotides is accompanied by stimulation of phospholipase D (PLD) activity. Overexpression of both PLD1 and PLD2 in SK-OV-3 cells produces active enzymes, but only overexpression of PLD2 results in significant amplification of both nucleotide-stimulated PLD activity and LPA production. SK-OV-3 cells express and secrete a phospholipase A2 activity that can generate LPA from the lipid product of PLD, phosphatidic acid. Our results identify a novel role for nucleotides in the regulation of ovarian cancer cells and suggest an indirect but critical function for PLD2 in agonist-stimulated LPA production.
AB - Lysophosphatidic acid (LPA) is a receptor-active lipid mediator with a broad range of biological effects. Ovarian cancer cells synthesize LPA, which promotes their motility, growth, and survival. We show that a murine homolog of a human protein previously reported to hydrolyze LPA is a highly selective detergent-stimulated LPA phosphatase that can be used to detect and quantitate LPA. Use of this protein in novel enzymatic assay demonstrates that SK-OV-3 ovarian cancer cells release physiologically relevant levels of biologically active LPA into the extracellular space. LPA release is markedly increased by nucleotide agonists acting through a P2Y4 purinergic receptor. Promotion of LPA formation by nucleotides is accompanied by stimulation of phospholipase D (PLD) activity. Overexpression of both PLD1 and PLD2 in SK-OV-3 cells produces active enzymes, but only overexpression of PLD2 results in significant amplification of both nucleotide-stimulated PLD activity and LPA production. SK-OV-3 cells express and secrete a phospholipase A2 activity that can generate LPA from the lipid product of PLD, phosphatidic acid. Our results identify a novel role for nucleotides in the regulation of ovarian cancer cells and suggest an indirect but critical function for PLD2 in agonist-stimulated LPA production.
KW - Adenosine 5′-triphosphate
KW - Enzymatic assay
KW - Lysophosphatidic acid phosphatase
KW - Phosphatidic acid
KW - Phospholipase A
KW - Phospholipase D1/phospholipase D2 isoforms
KW - Purinergic receptor
KW - Uridine 5′ triphosphate
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U2 - 10.1194/jlr.M300188-JLR200
DO - 10.1194/jlr.M300188-JLR200
M3 - Article
C2 - 12837850
AN - SCOPUS:0242290818
SN - 0022-2275
VL - 44
SP - 1963
EP - 1975
JO - Journal of Lipid Research
JF - Journal of Lipid Research
IS - 10
ER -
