Clinical & Experimental Metastasis

, Volume 21, Issue 8, pp 685–697

Ovarian carcinoma spheroids disaggregate on type I collagen and invade live human mesothelial cell monolayers

  • Kathryn M. Burleson
  • Linda K. Hansen
  • Amy P. N. Skubitz

DOI: 10.1007/s10585-004-5768-5

Cite this article as:
Burleson, K.M., Hansen, L.K. & Skubitz, A.P.N. Clin Exp Metastasis (2005) 21: 685. doi:10.1007/s10585-004-5768-5


Ovarian carcinoma patients frequently develop malignant ascites containing single and aggregated tumor cells, or spheroids. Spheroids have been shown to be resistant to many therapies, but their contribution to ovarian cancer dissemination remains undetermined. We have previously shown that ascites spheroids adhere to extracellular matrix (ECM) proteins and live human mesothelial cells via β1 integrin subunits. Here, we assessed the ability of spheroids that were generated from the human ovarian carcinoma cell line NIH: OVCAR5 to disseminate and invade in vitro. Spheroids were seeded on ECM proteins for 24 h. While laminin and type IV collagen stimulated some cell migration, spheroids completely disaggregated on type I collagen substrates. A monoclonal antibody against the β1 integrin subunit significantly inhibited disaggregation on all proteins tested. To test their invasive ability, spheroids were added to monolayers of live human LP9 mesothelial cells. Within 24 h, the spheroids adhered and disaggregated on top of the monolayers, and within a week had established foci of invasion encompassing a 200-fold larger surface area. Addition of a monoclonal antibody against the β1 integrin subunit drastically reduced spheroid invasion into the mesothelial cell monolayers. GM 6001, a broad-scale matrix metalloproteinase inhibitor, also significantly blocked spheroid invasion into the mesothelial cell monolayers. ɛ-amino-N-caproic acid, a serine protease inhibitor, partially inhibited spheroid invasion. Based on their ability to attach to, disaggregate on, and invade into live human mesothelial cell monolayers, spheroids should thus be regarded as potential contributors to the dissemination of ovarian cancer.


cell adhesion moleculesextracellular matrixintegrinsovarian carcinomaspheroids



bovine serum albumin


dimethyl sulfoxide


extracellular matrix


ethylenediaminetetraacetic acid




fetal bovine serum


monoclonal antibody


normal mouse immunoglobulin


matrix metalloproteinase


phosphate buffered saline


ɛ–amino-n-caproic acid


urinary-type plasminogen activator

Copyright information

© Springer 2005

Authors and Affiliations

  • Kathryn M. Burleson
    • 1
  • Linda K. Hansen
    • 1
  • Amy P. N. Skubitz
    • 1
  1. 1.Department of Laboratory Medicine and PathologyUniversity of MinnesotaMinneapolisUSA