title: 3,5,3',4',5'-pentamethoxystilbene (MR-5), a synthetically methoxylated analogue of resveratrol, inhibits growth and induces G1 cell cycle arrest of human breast carcinoma MCF-7 cells.
abstract: 3,5,3',4',5'-pentamethoxystilbene (MR-5) is a synthetically methoxylated analogue of resveratrol and has been suggested to have antitumor activity because of structural similarity to resveratrol. Herein, we investigate the antiproliferative effect of MR-5 in human breast cancer MCF-7 cells and demonstrate that MR-5 had a more potent inhibition on cell growth compared with resveratrol and other methoxylated derivatives. Exploring the growth-inhibitory mechanisms of MR-5, we found that it is accompanied by G1 cell cycle arrest, which coincides with a marked inhibition of G1 cell cycle regulatory proteins, including decreased cyclins (D1/D3/E) and cyclin-dependent kinases (CDK2/4/6) and increased CDK inhibitors (CKIs) such as p15, p16, p21, and p27. Furthermore, the increase in CKI levels by MR-5 resulted in a concomitant increase in their interactions of CDK4 and CDK2, along with a strong inhibition in CDK4 kinase activity and the accumulation of hypophosphorylated Rb. MR-5 also modulated some critical kinase activities related to cell cycle regulation, including Akt, mitogen-activated protein kinase (ERK1/2), p38 mitogen-activated protein kinase (p38 MAPK), and focal adhesion kinase (FAK) in MCF-7 cells. In total, our results demonstrate that MR-5 affects multiple cellular targets that contribute to its antiproliferative activity in MCF-7 cells and provide novel information for synthetic chemists to design new antitumor agents with introduction of methoxylated group(s) in the basic compound.
authors.affiliation: Department of Seafood Science, National Kaohsiung Marine University, No. 142 Hai-Chuan Road, Nan-Tzu, Kaohsiung 811, Taiwan.
authors.forename: Min-Hsiung
authors.initials: MH
authors.lastname: Pan
authors.forename: Chih-Li
authors.initials: CL
authors.lastname: Lin
authors.forename: Jie-Heng
authors.initials: JH
authors.lastname: Tsai
authors.forename: Chi-Tang
authors.initials: CT
authors.lastname: Ho
authors.forename: Wei-Jen
authors.initials: WJ
authors.lastname: Chen
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D002277:Carcinoma / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D002453:Cell Cycle / Q000187:drug effects*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006131:Growth Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*; D006801:Humans; D013267:Stilbenes / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: C494914:3,5,3',4',5'-pentamethoxystilbene; D018797:Cell Cycle Proteins; D006131:Growth Inhibitors; D013267:Stilbenes