Tumor-specificity and apoptosis-inducing activity of stilbenes and flavonoids.
A total of eleven stilbenes [1-6] and flavonoids [7-11] were investigated for their tumor- specific cytotoxicity and apoptosis-inducing activity, using four human tumor cell lines (squamous cell carcinoma HSC-2, HSC-3, submandibular gland carcinoma HSG and promyelocytic leukemia HL-60) and three normal human oral cells (gingival fibroblast HGF, pulp cell HPC, periodontal ligament fibroblast HPLF). All of the compounds, especially sophorastilbene A [1], (+)-alpha-viniferin [2], piceatannol [5], quercetin [9] and isoliquiritigenin [10], showed higher cytotoxicity against the tumor cell lines than normal cells, yielding tumor-specific indices of 3.6, 4.7, >3.5, >3.3 and 4.0, respectively. Among the seven cell lines, HSC-2 and HL-60 cells were the most sensitive to the cytotoxic action of these compounds. Sophorastilbene A [1], piceatannol [5], quercetin [9] and isoliquiritigenin [10] induced internucleosomal DNA fragmentation and activation of caspases -3, -8 and -9 dose-dependently in HL-60 cells. (+)-alpha-Viniferin [2] showed similar activity, but only at higher concentrations. All the compounds failed to induce DNA fragmentation and activated caspases to much lesser extents in HSC-2 cells. Western blot analysis showed that sophorastilbene A [1], piceatannol [5] and quercetin [9] did not induce any consistent changes in the expression of pro-apoptotic proteins (Bax, Bad) and antiapoptotic protein (Bcl-2) in HL-60 and HSC-2 cells. An undetectable expression of Bcl-2 protein in control and drug-treated HSC-2 cells may explain the relatively higher sensitivity of this cell line to stilbenes and flavonoids.
Chowdhury
Shahead Ali
SA
Meikai Pharmaco-Medical Laboratory (MPL), Meikai University School of Dentistry, Sakado, Saitama, Japan.
Kishino
Kaori
K
Satoh
Rie
R
Hashimoto
Ken
K
Kikuchi
Hirotaka
H
Nishikawa
Hirofumi
H
Shirataki
Yoshiaki
Y
Sakagami
Hiroshi
H
D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D004354:Drug Screening Assays, Antitumor; D005347:Fibroblasts / Q000187:drug effects; D005419:Flavonoids / Q000494:pharmacology*; D018922:HL-60 Cells; D006801:Humans; D013267:Stilbenes / Q000494:pharmacology*
D005419:Flavonoids; D013267:Stilbenes