Inhibition of focal adhesion kinase (FAK) activity prevents anchorage-independent ovarian carcinoma cell growth and tumor progression

Clin Exp Metastasis. 2013 Jun;30(5):579-94. doi: 10.1007/s10585-012-9562-5. Epub 2012 Dec 30.

Abstract

Recurrence and spread of ovarian cancer is the 5th leading cause of death for women in the United States. Focal adhesion kinase (FAK) is a cytoplasmic protein-tyrosine kinase located on chromosome 8q24.3 (gene is Ptk2), a site commonly amplified in serous ovarian cancer. Elevated FAK mRNA levels in serous ovarian carcinoma are associated with decreased (logrank P = 0.0007, hazard ratio 1.43) patient overall survival, but how FAK functions in tumor progression remains undefined. We have isolated aggressive ovarian carcinoma cells termed ID8-IP after intraperitoneal (IP) growth of murine ID8 cells in C57Bl6 mice. Upon orthotopic implantation within the peri-ovarian bursa space, ID8-IP cells exhibit greater tumor growth, local and distant metastasis, and elevated numbers of ascites-associated cells compared to parental ID8 cells. ID8-IP cells exhibit enhanced growth under non-adherent conditions with elevated FAK and c-Src tyrosine kinase activation compared to parental ID8 cells. In vitro, the small molecule FAK inhibitor (Pfizer, PF562,271, PF-271) at 0.1 uM selectively prevented anchorage-independent ID8-IP cell growth with the inhibition of FAK tyrosine (Y)397 but not c-Src Y416 phosphorylation. Oral PF-271 administration (30 mg/kg, twice daily) blocked FAK but not c-Src tyrosine phosphorylation in ID8-IP tumors. This was associated with decreased tumor size, prevention of peritoneal metastasis, reduced tumor-associated endothelial cell number, and increased tumor cell-associated apoptosis. FAK knockdown and re-expression assays showed that FAK activity selectively promoted anchorage-independent ID8-IP cell survival. These results support the continued evaluation of FAK inhibitors as a promising clinical treatment for ovarian cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Division / drug effects*
  • Disease Progression*
  • Female
  • Focal Adhesion Protein-Tyrosine Kinases / antagonists & inhibitors*
  • Focal Adhesion Protein-Tyrosine Kinases / genetics
  • Humans
  • Ovarian Neoplasms / enzymology
  • Ovarian Neoplasms / pathology*
  • Protein Kinase Inhibitors / pharmacology*
  • RNA, Messenger / genetics

Substances

  • Protein Kinase Inhibitors
  • RNA, Messenger
  • Focal Adhesion Protein-Tyrosine Kinases