title: Trans- and cis-stilbene polyphenols induced rapid perinuclear mitochondrial clustering and p53-independent apoptosis in cancer cells but not normal cells.
abstract: We previously reported that 3,4,5,4'-tetramethoxy-trans-stilbene (MR-4) induces p53 and perinuclear mitochondrial clustering in cancer cells [Gosslau, A., Chen, M., Ho, C.-T., Chen, K.Y., 2005, A methoxy derivative of resveratrol analogue selectively induced activation of the mitochondrial apoptotic pathway in transformed fibroblasts. Br. J. Cancer 92, 513-521.]. Here we extended the study to over 20 trans-stilbene derivatives and their cis-isomers to explore structure activity relationship. Among them, 3,4,5,4'-tetramethoxy-cis-stilbene (MC-4), the cis-isomer of MR-4, was most potent, with IC50 of 20 nM for growth inhibition. MC-4 induced a rapid perinuclear mitochondrial clustering, membrane permeability transition, cytochrome c release and DNA fragmentation. To determine whether trans- and cis-stilbene polyphenols may share a common mechanism, we compared the effects of MC-4 and MR-4 in three isogenic cell lines derived from the colorectal carcinoma HCT116 cells: p53+/+ (p53-wt), p53-/- (p53-null) and p21-/- (p21-null). Deletion of either p53 or p21 neither blocked the effects of MC-4 or MR-4 on mitochondrial clustering nor inhibited apoptosis, indicating that the actions of both stilbenes are independent of p53 and p21. Although microtubule disruption has been proposed to account for the action of some cis-stilbene polyphenols, we did not observe differences in microtubule dynamics between cells treated with MC-4 and MR-4. These findings suggest that MC-4 and MR-4 may share a common mechanism whereby the perinucear mitochondrial clustering, rather than p53, p21, or microtubule depolymerization, is critical for their pro-apoptotic action.
authors.affiliation: Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8087, United States.
authors.forename: Alexander
authors.initials: A
authors.lastname: Gosslau
authors.forename: Srihari
authors.initials: S
authors.lastname: Pabbaraja
authors.forename: Spencer
authors.initials: S
authors.lastname: Knapp
authors.forename: Kuang Yu
authors.initials: KY
authors.lastname: Chen
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004789:Enzyme Activation / Q000502:physiology; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D005456:Fluorescent Dyes; D006801:Humans; D008564:Membrane Potentials / Q000187:drug effects; D008870:Microtubules / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects*; D051336:Mitochondrial Membranes / Q000187:drug effects; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology*; D059808:Polyphenols; D020112:Rhodamine 123; D013267:Stilbenes / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology*
chemical_list: C440850:2,4,3',5'-tetramethoxystilbene; D005419:Flavonoids; D005456:Fluorescent Dyes; D010636:Phenols; D059808:Polyphenols; D013267:Stilbenes; D016159:Tumor Suppressor Protein p53; D020112:Rhodamine 123; D045304:Cytochromes c; D020169:Caspases