Itoh Shinji, Shibutani Shinya, Ikegami Masazumi, Watanabe Shingo, Laxmi Y R Santosh, Suzuki Naomi, Kohda Kohfuku, Takanashi Kaori, Yoshizawa Itsuo
Hokkaido Pharmaceutical University School of Pharmacy, 7-1, Katsuraoka-cho, Otaru, Hokkaido 047-0264, Japan.
Chem Res Toxicol. 2006 Mar;19(3):450-6. doi: 10.1021/tx0503294.
DNA damage induced by estrogens is associated with developing breast, ovary, and endometrial cancers. The quinone of 2-hydroxyestrogen (2-OHE), a major estrogen metabolite, produces 2-OHE-derived dG and dA adducts in DNA. N(2)-[Estradiol-6(alpha or beta)-yl]-2'-deoxyguanosine [dG-N(2)-6(alpha or beta)-E(2)] lacking a 2-OH moiety may also be formed through sulfonation of 6-hydroxyestrogen. To explore the biological properties of such estrogen-DNA adducts, oligodeoxynucleotides modified by estrogen-derived DNA adduct were prepared by chemical synthesis. Initially, 6alpha- and 6beta-aminoestradiol 17-acetate (6alpha- and 6beta-NH(2)-E(2) 17Ac) were prepared by reductive amination of 6-oxo-estradiol 3,17-diacetate. The DMT-phosphoramidite derivative of N(2)-(3,17-diacetoxyestradiol-6alpha-yl)-2'-deoxyguanosine and its 6beta-isomer were prepared by coupling 5'-O-(4,4'-dimethoxytrityl)-2-fluoro-O(6)-[2-(4-nitrophenyl)ethyl]-2'-deoxyinosine separately with 6alpha- and 6beta-forms of NH(2)-E(2) 17Ac, respectively, followed by selective acetylation of the steroidal 3-hydroxyl group. The desired oligodeoxynucleotide containing a single dG-N(2)-6alpha-E(2) or dG-N(2)-6beta-E(2) was prepared efficiently by an automated DNA synthesizer. Synthesis of these site-specifically modified oligodeoxynucleotides will benefit further research into the biological properties and three-dimensional structure of 6alpha- and 6beta-diastereoisomers of estrogen-DNA adducts.
雌激素诱导的DNA损伤与乳腺癌、卵巢癌和子宫内膜癌的发生有关。2-羟基雌激素（2-OHE）的醌类，一种主要的雌激素代谢产物，在DNA中产生2-OHE衍生的dG和dA加合物。缺乏2-OH部分的N(2)-[雌二醇-6(α或β)-基]-2'-脱氧鸟苷[dG-N(2)-6(α或β)-E(2)]也可能通过6-羟基雌激素的磺化形成。为了探索此类雌激素-DNA加合物的生物学特性，通过化学合成制备了经雌激素衍生的DNA加合物修饰的寡脱氧核苷酸。最初，通过对3,17-二乙酰氧基-6-氧代雌二醇进行还原胺化反应制备了6α-和6β-氨基雌二醇17-乙酸酯（6α-和6β-NH(2)-E(2) 17Ac）。分别将5'-O-(4,4'-二甲氧基三苯甲基)-2-氟-O(6)-[2-(4-硝基苯基)乙基]-2'-脱氧肌苷与6α-和6β-形式的NH(2)-E(2) 17Ac偶联，随后对甾体3-羟基进行选择性乙酰化，制备了N(2)-(3,17-二乙酰氧基雌二醇-6α-基)-2'-脱氧鸟苷及其6β-异构体的DMT-亚磷酰胺衍生物。通过自动DNA合成仪高效制备了含有单个dG-N(2)-6α-E(或dG-N(2)-6β-E(2)的所需寡脱氧核苷酸。这些位点特异性修饰的寡脱氧核苷酸的合成将有助于进一步研究雌激素-DNA加合物的6α-和6β-非对映异构体的生物学特性和三维结构。
