RNA interference: a potential strategy for isoform-specific phosphatidylinositol 3-kinase targeted therapy in ovarian cancer

Cancer Biol Ther. 2004 Dec;3(12):1283-9. doi: 10.4161/cbt.3.12.1388. Epub 2004 Dec 15.


Phosphatidylinositol 3-kinase (PI3-kinase) is a novel intracellular transducer involved in a wide range of cancer-associated signaling pathways, which comprises various isoforms and splice variants with distinct biologic activities and clinical implications. Especially, the class Ia PI3-kinase 110 kD catalytic subunit alpha (PIK3CA) is the most important isoform in tumorigenesis and possibly, tumor angiogenesis. Several strategies have been developed to block PI3-kinase for cancer therapy; however, the approach to target specific PI3-kinase isoform has not been explored to date. In the present study, we show that RNA interference (RNAi) through small interfering (siRNA) sequences targeting PIK3CA has potential applications in isoform-specific "knock-down" of PI3-kinase. This strategy provides a novel tool to study the function of various PI3-kinase isoforms and may contribute to isoform-specific targeting of PI3-kinase in human cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers, Tumor / metabolism
  • Blotting, Western
  • Cell Proliferation*
  • Class I Phosphatidylinositol 3-Kinases
  • Female
  • Genetic Vectors*
  • Humans
  • Mice
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / metabolism
  • Phosphatidylinositol 3-Kinases / genetics*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoinositide-3 Kinase Inhibitors
  • Protein Isoforms
  • RNA Interference
  • RNA, Small Interfering / pharmacology*
  • Tumor Cells, Cultured


  • Biomarkers, Tumor
  • Phosphoinositide-3 Kinase Inhibitors
  • Protein Isoforms
  • RNA, Small Interfering
  • Class I Phosphatidylinositol 3-Kinases
  • PIK3CA protein, human