上海藥物研究所藥物發(fā)現(xiàn)與設(shè)計(jì)中心(DDDC)蔣華良課題組羅成副研究員與美國(guó)賓夕法尼亞大學(xué)Wistar研究所Paul M. Lieberman教授合作，經(jīng)過(guò)近兩年的努力，在世界上首次發(fā)現(xiàn)多個(gè)小分子化合物能夠通過(guò)阻斷EBNA1與DNA的結(jié)合，進(jìn)而抑制EBV復(fù)制,。研究論文于2010年4月12日發(fā)表在《公共科學(xué)圖書(shū)館·綜合》PLoS ONE上,。
皰疹病毒(Epstein-Barr virus,，EBV)的潛伏感染能夠誘導(dǎo)伯基特淋巴瘤,、鼻咽癌,、胃癌和霍奇金淋巴瘤等多種淋巴細(xì)胞源性和上皮細(xì)胞源性的惡性腫瘤的產(chǎn)生,。在全球范圍內(nèi)，有90%以上的人感染過(guò)EBV,。因此,，EBV被世界衛(wèi)生組織列為人類(lèi)致癌病毒。到目前為止,，EBV感染引起的致癌作用不能得到有效地防止或治療,，世界上尚未有可有效用于治療與EBV所誘導(dǎo)的相關(guān)疾病的藥物或針對(duì)EBV潛伏感染的療法。因此,，尋找可作為清除EBV潛伏感染的理想靶標(biāo),，進(jìn)而用于藥物設(shè)計(jì)研究成為一直以來(lái)是當(dāng)前EBV研究的一個(gè)難點(diǎn)和熱點(diǎn)。
在本研究中,，羅成副研究員帶領(lǐng)博士研究生李寧針對(duì)EBNA1/DNA復(fù)合物晶體結(jié)構(gòu)(EBV nuclear antigen 1,，EBNA1，EBV核抗原1)與Lieberman教授開(kāi)展藥物設(shè)計(jì),、分子細(xì)胞生物學(xué)及病毒學(xué)研究,。EBNA1是一種EBV編碼的DNA結(jié)合蛋白，它表達(dá)于所有與EBV相關(guān)類(lèi)型的腫瘤細(xì)胞內(nèi),，是病毒潛伏期DNA復(fù)制,、游離基因維持和永生化初級(jí)B淋巴細(xì)胞所必不可少的。這項(xiàng)研究不僅首次發(fā)現(xiàn)一類(lèi)新型的小分子能夠通過(guò)抑制EBNA1結(jié)合DNA的功能進(jìn)而抑制EBV復(fù)制,。同時(shí),，它也證明了EBNA1可以作為治療EBV潛伏感染的理想靶標(biāo)，為將來(lái)抗皰疹病毒的藥物發(fā)現(xiàn)研究提供了一條切實(shí)可行之路,。
該研究標(biāo)志著上海藥物研究所已經(jīng)在預(yù)防和治療EBV潛伏感染所誘導(dǎo)的惡性腫瘤方面邁出了關(guān)鍵的一步,，并且該研究為開(kāi)發(fā)出能夠阻止EBV進(jìn)入潛伏期或打破潛伏期維持的藥物奠定了基礎(chǔ)。其次,，該成果為目前藥物設(shè)計(jì)研究的難點(diǎn)(針對(duì)蛋白質(zhì)/DNA或蛋白質(zhì)/蛋白質(zhì)復(fù)合物的藥物設(shè)計(jì))提供了一個(gè)可以借鑒的研究策略,，也將為其它抗病毒藥物的研究提供一條切實(shí)可行的思路。這項(xiàng)研究將極大地促進(jìn)治療EBV病毒潛伏感染的抗病毒藥物的發(fā)現(xiàn),。最后,，該研究也表明，實(shí)驗(yàn)科學(xué)與理論科學(xué)的有效整合,，將極大地促進(jìn)藥物發(fā)現(xiàn)研究,。
該研究項(xiàng)目得到了國(guó)家科技部、自然科學(xué)基金委、上海市科委,、新藥研究國(guó)家重點(diǎn)實(shí)驗(yàn)室開(kāi)放課題的資助,。(生物谷Bioon.com)
生物谷推薦原文出處：
PLoS ONE doi:10.1371/journal.pone.0010126
Discovery of Selective Inhibitors Against EBNA1 via High Throughput In Silico Virtual Screening
Ning Li1#, Scott Thompson2#, David C. Schultz2, Weiliang Zhu1, Hualiang Jiang1, Cheng Luo1*, Paul M. Lieberman2*
1 Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China, 2 The Wistar Institute, Philadelphia, Pennsylvania, United States of America
Epstein-Barr Virus (EBV) latent infection is associated with several human malignancies and is a causal agent of lymphoproliferative diseases during immunosuppression. While inhibitors of herpesvirus DNA polymerases, like gancyclovir, reduce EBV lytic cycle infection, these treatments have limited efficacy for treating latent infection. EBNA1 is an EBV-encoded DNA-binding protein required for viral genome maintenance during latent infection.
Here, we report the identification of a new class of small molecules that inhibit EBNA1 DNA binding activity. These compounds were identified by virtual screening of 90,000 low molecular mass compounds using computational docking programs with the solved crystal structure of EBNA1. Four structurally related compounds were found to inhibit EBNA1-DNA binding in biochemical assays with purified EBNA1 protein. Compounds had a range of 20–100 ??M inhibition of EBNA1 in fluorescence polarization assays and were further validated for inhibition using electrophoresis mobility shift assays. These compounds exhibited no significant inhibition of an unrelated DNA binding protein. Three of these compounds inhibited EBNA1 transcription activation function in cell-based assays and reduced EBV genome copy number when incubated with a Burkitt lymphoma cell line.
These experiments provide a proof-of-principle that virtual screening can be used to identify specific inhibitors of EBNA1 that may have potential for treatment of EBV latent infection.
