title: Platelets increase the proliferation of ovarian cancer cells.
abstract: Platelets promote metastasis and angiogenesis, but their effect on tumor cell growth is uncertain. Here we report a direct proliferative effect of platelets on cancer cells both in vitro and in vivo. Incubation of platelets with ovarian cancer cells from murine (ID8 and 2C6) or human (SKOV3 and OVCAR5) origin increased cell proliferation. The proliferative effect of platelets was not dependent on direct contact with cancer cells, and preincubation of platelets with blocking antibodies against platelet adhesion molecules did not alter their effect on cancer cells. The proliferative effect of platelets was reduced by fixing platelets with paraformaldehyde, preincubating platelets with a TGF-β1-blocking antibody, or reducing expression of TGF-βR1 receptor on cancer cells with siRNA. Infusing platelets into mice with orthotopic ovarian tumors significantly increased the proliferation indices in these tumors. Ovarian cancer patients with thrombocytosis had higher tumor proliferation indices compared with patients with normal platelet counts.
authors.affiliation: Departments of Benign Hematology, University of Texas MD Anderson CancerCenter, Houston, TX 77030, USA.
authors.forename: Min Soon
authors.initials: MS
authors.lastname: Cho
authors.forename: Justin
authors.initials: J
authors.lastname: Bottsford-Miller
authors.forename: Hernan G
authors.initials: HG
authors.lastname: Vasquez
authors.forename: Rebecca
authors.initials: R
authors.lastname: Stone
authors.forename: Behrouz
authors.initials: B
authors.lastname: Zand
authors.forename: Michael H
authors.initials: MH
authors.lastname: Kroll
authors.forename: Anil K
authors.initials: AK
authors.lastname: Sood
authors.forename: Vahid
authors.initials: V
authors.lastname: Afshar-Kharghan
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D010051:Ovarian Neoplasms / Q000150:complications / Q000473:pathology* / Q000628:therapy; D010976:Platelet Count; D017713:Platelet Transfusion; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D013922:Thrombocytosis / Q000150:complications
chemical_list: D019394:Ki-67 Antigen; D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I