Clinical Significance of Heparin-Binding Epidermal Growth Factor^Like Growth Factor and A Disintegrin and Metalloprotease17 Expressionin Human Ovarian Cancer Yoshihiro Tanaka, 1 ShingoMiyamoto, 1 Satoshi O. Suzuki, 2 Eiji Oki, 3 Hiroshi Yagi, 1 Kenzo Sonoda, 1 Ayano Yamazaki, 4 HirotoMizushima, 4 YoshihikoMaehara, 3 EisukeMekada, 4 and Hitoo Nakano 1 Abstract Purpose: Lysophosphatidic acid, which is enriched in the peritoneal fluid of ovarian cancer patients,playsakeyroleintheprogressionofovariancancer.Lysophosphatidicacidcangenerate epidermal growth factor receptor (EGFR) signal transactivation involving processing of EGFR ligands byADAM (a disintegrin and metalloprotease) family metalloproteases.We aimed to investigate the clinical significance of EGFR ligands and ADAM family in the lysophosphatidic acid^induced pathogenesis of ovarian cancer. Experimental Design: We examined the expression of EGFR ligands and ADAM family members in108 patients with normal ovaries or ovarian cancer, using real-time PCR, immuno- histochemistry, and in situ hybridization, and analyzed the clinical roles of these molecules. StatisticalanalysesofthesedataweredoneusingtheMann-Whitneytest,Kaplan-Meiermethod, orSpearman’scorrelationanalysis. Results: Large differences in expression were found for heparin-binding EGF-like growth factor (HB-EGF) and other EGFR ligands and forADAM17 and otherADAM family members. HB-EGF expression was significantly increased in advanced ovarian cancer compared with that in normal ovaries ( P < 0.01).HB-EGFexpressionwassignificantlyassociatedwiththeclinicaloutcome(P < 0.01).ADAM17expressionwassignificantlyenhancedinbothearlyandadvancedovariancancer compared with that in normal ovaries (both P < 0.01), although it had no clinical significance in the progression-free survival. HB-EGF expression was significantly correlated with ADAM17 expression(c =0.437, P < 0.01). Conclusions: Our findings suggest that HB-EGFand ADAM17 contribute to the progressionof ovariancancerandthatHB-EGFplaysapivotalroleintheaggressivebehaviorofatumorinovarian cancer. Ovarian cancer is the most common cause of death from a gynecologic malignancy in most countries (1). The high mortality is predominantly due to occult progression of the tumor in the peritoneal cavity, with the initial diagnosis usually being made at an advanced stage. Currently, f75% of ovarian cancers are diagnosed at International Federation of Gynecology and Obstetrics stages III and IV (2). Extensive dissemination of a tumor is caused by the peritoneal fluid following the circulatory pathway in the abdominal cavity, and the peritoneal fluid acts as a rich source of growth factor activity for ovarian cancer cells (3). Thus, the dissemination of cancer cells activated by ovarian cancer – activating factors results in an exaggerated increase in peritoneal fluid, which in turn leads to tumor extension in ovarian cancer. Therefore, to develop a targeting therapy, it would be extremely useful to understand the ovarian cancer – activating factor – mediated molecular mechanisms for activating ovar- ian cancer cells. Lysophosphatidic acid (LPA) is a simple phospholipid with numerous cellular effects, including growth promotion, cell cycle progression, and cytoskeletal organization (4), and is generated from precursors in membranes. LPA is elevated in the plasma and peritoneal fluid from patients with ovarian cancer in all stages, suggesting that it is a possible candidate for an ovarian cancer – activating factor (5–8). In principle, LPA-induced signaling is mediated by G protein – coupled receptors, includ- ing LPA1, LPA2, LPA3, and LPA4 (4). Recent investigations have shown that G protein – coupled receptors are able to use the epidermal growth factor receptor (EGFR) as a downstream signaling partner in the generation of mitogenic signals (9), and Imaging, Diagnosis, Prognosis Authors’Affiliations: Departments of 1 Obstetrics and Gynecology, 2 Neuropathology, 3 Surgery and Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan and 4 Department of Cell Biology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan Received7/21/04;revised12/7/04;accepted12/15/04. Grant support: Ministry of Health andWelfare ofJapan Grant-in-Aid for Cancer Research16591667 (S. Miyamoto) and Ministry of Education, Culture, Sports, Science and Technology Grant-in-aid for Scientific Research on PriorityAreas 14032202(E.Mekada). Thecostsofpublicationofthisarticleweredefrayedinpartbythepaymentofpage charges.This article must therefore be hereby marked advertisement in accordance with18U.S.C.Section1734solely toindicatethisfact. Requests for reprints: Shingo Miyamoto, Department of Obstetrics and Gynecology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Phone: 81-92-642-5395; Fax: 81-92-642-5414;E-mail:smiya@ @cis.fukuoka-u.ac.jp. F 2005AmericanAssociationforCancerResearch. www.aacrjournals.org Clin Cancer Res 2005;11(13) July1, 2005 4783