Peritoneal fluids from patients with certain gynecologic tumor contain elevated levels of bioactive lysophospholipase D activity.
Levels of lysophosphatidic acid (LPA), an important phospholipid mediator, in serum and ascitic fluid from ovarian cancer patients were shown to be higher than those from healthy women and from patients with other type of cancer, respectively. Although LPA in human serum seems mainly to be generated by lysophospholipase D (lysoPLD), the source and pathway for LPA in the ascitic fluid remain still obscure. In this study, we examined whether lysoPLD activity producing bioactive LPA in human peritoneal fluid was significantly elevated under pathological statuses. Lysophospholipase D activity in human peritoneal fluids was measured by quantifying choline released from exogenous lysophosphatidylcholine on their incubation at 37 degrees C. We also compared the activity of lysoPLD in sera from patients with different gynecologic diseases. We found relatively high lysoPLD activity in peritoneal fluids from patients with ovarian cancer, dermoid cyst or mucinous cystadenoma, whereas there were no significant differences in the serum lysoPLD activity among clinical groups and healthy subjects. The lysoPLD in the peritoneal fluid was found to have similar substrate specificity and metal ion requirement to those of serum lysoPLD, that has been identified as autotaxin, a tumor cell-motility stimulating protein. Our results suggest that increased lysoPLD activity in peritoneal fluid from patients with certain gynecologic tumors might be relevant to its potential of tumor progression.
Tokumura
Akira
A
Department of Health Chemistry, Institute of Health Biosciences, University of Tokushima Graduate School, 1-78-1 Shomachi, Tokushima, Japan. tokumura@ph.tokushima-u.ac.jp
Kume
Tetsuya
T
Fukuzawa
Kenji
K
Tahara
Masahiro
M
Tasaka
Keiichi
K
Aoki
Junken
J
Arai
Hiroyuki
H
Yasuda
Katsuhiko
K
Kanzaki
Hideharu
H
D000328:Adult; D001202:Ascitic Fluid / Q000201:enzymology*; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood; D002794:Choline / Q000032:analysis; D018291:Cystadenoma, Mucinous / Q000097:blood / Q000201:enzymology*; D003884:Dermoid Cyst / Q000097:blood / Q000201:enzymology*; D005260:Female; D006801:Humans; D008246:Lysophospholipids / Q000032:analysis / Q000097:blood; D009097:Multienzyme Complexes / Q000032:analysis / Q000097:blood; D010051:Ovarian Neoplasms / Q000097:blood / Q000201:enzymology*; D043264:Phosphodiesterase I / Q000032:analysis / Q000097:blood; D010727:Phosphoric Diester Hydrolases / Q000032:analysis* / Q000097:blood; D011755:Pyrophosphatases / Q000032:analysis / Q000097:blood; D000099189:Lysophospholipase D
D014408:Biomarkers, Tumor; D002794:Choline; D008246:Lysophospholipids; D009097:Multienzyme Complexes; D043264:Phosphodiesterase I; D010727:Phosphoric Diester Hydrolases; D011755:Pyrophosphatases; D000099189:Lysophospholipase D; C032881:lysophosphatidic acid