RRC ID 43957
Author Mooi LY, Yew WT, Hsum YW, Soo KK, Hoon LS, Chieng YC.
Title Suppressive effect of maslinic acid on PMA-induced protein kinase C in human B-lymphoblastoid cells.
Journal Asian Pac J Cancer Prev
Abstract Protein kinase C (PKC) has been implicated in carcinogenesis and displays variable expression profiles during cancer progression. Studies of dietary phytochemicals on cancer signalling pathway regulation have been conducted to search for potent signalling regulatory agents. The present study was designed to evaluate any suppressive effect of maslinic acid on PKC expression in human B-lymphoblastoid cells (Raji cells), and to identify the PKC isoforms expressed. Effects of maslinic acid on PKC activity were determined using a PepTag assay for non-radioactive detection of PKC. The highest expression in Raji cells was obtained at 20 nM PMA induced for 6 hours. Suppressive effects of maslinic acid were compared with those of four PKC inhibitors (H- 7, rottlerin, sphingosine, staurosporine) and two triterpenes (oleanolic acid and ursolic acid). The IC₅₀ values achieved for maslinic acid, staurosporine, H-7, sphingosine, rottlerin, ursolic acid and oleanolic acid were 11.52, 0.011, 0.767, 2.45, 5.46, 27.93 and 39.29 μM, respectively. Four PKC isoforms, PKC βI, βII, δ, and ζ, were identified in Raji cells via western blotting. Maslinic acid suppressed the expression of PKC βI, δ, and ζ in a concentration-dependent manner. These preliminary results suggest promising suppressive effects of maslinic acid on PKC activity in Raji cells. Maslinic acid could be a potent cancer chemopreventive agent that may be involved in regulating many downstream signalling pathways that are activated through PKC receptors.
Volume 13(4)
Pages 1177-82
Published 2012-1-1
DOI 10.7314/apjcp.2012.13.4.1177
PMID 22799301
MeSH 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / pharmacology Acetophenones / pharmacology Anticarcinogenic Agents / pharmacology Benzopyrans / pharmacology Cells, Cultured Enzyme Inhibitors / pharmacology* Humans Inhibitory Concentration 50 Isoenzymes / drug effects Isoenzymes / isolation & purification Oleanolic Acid / pharmacology Precursor Cells, B-Lymphoid / drug effects* Precursor Cells, B-Lymphoid / enzymology* Protein Kinase C / drug effects Protein Kinase C / metabolism* Sphingosine / pharmacology Staurosporine / pharmacology Tetradecanoylphorbol Acetate / pharmacology Triterpenes / pharmacology*
Times Cited 9
Human and Animal Cells