Linkage of reduction in 1-phosphatidylinositol 4-kinase activity and inositol 1,4,5-trisphosphate concentration in human ovarian carcinoma cells treated with quercetin

Noemi Prajda, Radhey L. Singhal, Y. Albert Yeh, Edith Olah, Katherine Y. Look, George Weber

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30 Citations (Scopus)


Quercetin inhibited 1 -phosphatidylinositol (PI) 4-kinase, EC (PI kinase) activity in a concentration-dependent manner (IC50 = 4 μM) in participate extracts from human ovarian carcinoma. In OVCAR-5 cells quercetin produced growth inhibition (IC 50 = 63 μM) and cytotoxicity (LC50 = 17μM). The growth inhibition by quercetin was accompanied by an 80% decrease in PI kinase activity and a 65% decrease in the concentration of the second messenger, inositol 1,4,5-trisphosphate (IP3). When human OVCAR-5 cells were plated and expressed their neoplastic proliferative program in the log phase, PI kinase and PI 4-phosphate 5-kinase, EC (PIP kinase) activities coordinately increased to a peak of 5.8- and 4.5-fold, respectively. The results demonstrate for the first time inhibition by quercetin of the enhanced capacity for operation of signal transduction in human ovarian carcinoma cells, thus providing a novel target in cancer cells.

Original languageEnglish
Pages (from-to)1587-1593
Number of pages7
JournalLife Sciences
Issue number19
Publication statusPublished - Mar 31 1995



  • IP
  • PI kinase
  • ovarian carcinoma
  • quercetin

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)

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