Lysophosphatidic acid (LPA) promotes E-cadherin ectodomain shedding and OVCA429 cell invasion in an uPA-dependent manner.
OBJECTIVE
To evaluate the role of LPA in regulating E-cadherin cell surface expression, adhesion, and invasion in epithelial ovarian carcinoma (EOC) cells.


METHODS
E-cadherin mRNA expression in OVCA429 and IOSE-29 cells was evaluated by real-time RT-PCR. Immunofluorescence and Western blot analysis were performed to determine cell surface expression and shedding of E-cadherin 80-kDa soluble fragment by LPA. Kinetics of LPA-induced uPA activity was followed with a colorimetric enzymatic assay. Invasion assays were performed in a modified Boyden chamber where cells were allowed to migrate to the bottom compartment through a porous filter coated with collagen. Additionally we measured the 80-kDa form from the ascites of women with stage III/IV EOC.


RESULTS
LPA induces E-cadherin shedding of a soluble 80-kDa fragment. We found that this process is mediated by the uPA proteolytic cascade. High levels of soluble E-cadherin were found in the ascites from women with advanced stage EOC. LPA and a soluble recombinant E-cadherin-Fc chimera promotes invasion of OVCA429 cells.


CONCLUSIONS
LPA induces shedding of an 80-kDa E-cadherin-soluble fragment in an uPA-dependent manner and promotes in vitro invasion. High levels of soluble E-cadherin in malignant ascites may also affect ovarian metastasis.
Gil
Orlando D
OD
Department of Obstetrics and Gynecology, New York University School of Medicine, 550 First Avenue, TH-528, New York, NY 10016, USA.
Lee
Catherine
C
Ariztia
Edgardo V
EV
Wang
Feng-Qiang
FQ
Smith
Phillip J
PJ
Hope
Joanie Mayer
JM
Fishman
David A
DA
D015820:Cadherins / Q000096:biosynthesis* / Q000235:genetics; D045744:Cell Line, Tumor; D015536:Down-Regulation; D005260:Female; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000235:genetics; D008246:Lysophospholipids / Q000494:pharmacology*; D009361:Neoplasm Invasiveness; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014568:Urokinase-Type Plasminogen Activator / Q000037:antagonists & inhibitors / Q000378:metabolism*
D015820:Cadherins; D007141:Immunoglobulin Fc Fragments; D008246:Lysophospholipids; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014568:Urokinase-Type Plasminogen Activator; C032881:lysophosphatidic acid