Chandra Nagasuma, Bhagavat Raghu, Sharma Eshita, Sreekanthreddy P, Somasundaram Kumaravel
Bioinformatics Centre, Indian Institute of Science, Bangalore 560012, India.
J Clin Bioinforma. 2011 Jan 20;1(1):5. doi: 10.1186/2043-9113-1-5.
Pre-B-cell colony enhancing factor 1 gene (PBEF1) encodes nicotinamide phosphoribosyltransferase (NMPRTase), which catalyses the rate limiting step in the salvage pathway of NAD+ metabolism in mammalian cells. PBEF1 transcript and protein levels have been shown to be elevated in glioblastoma and a chemical inhibitor of NMPRTase has been shown to specifically inhibit cancer cells.
Virtual screening using docking was used to screen a library of more than 13,000 chemical compounds. A shortlisted set of compounds were tested for their inhibition activity in vitro by an NMPRTase enzyme assay. Further, the ability of the compounds to inhibit glioma cell proliferation was carried out.
Virtual screening resulted in short listing of 34 possible ligands, of which six were tested experimentally, using the NMPRTase enzyme inhibition assay and further with the glioma cell viability assays. Of these, two compounds were found to be significantly efficacious in inhibiting the conversion of nicotinamide to NAD+, and out of which, one compound, 3-amino-2-benzyl-7-nitro-4-(2-quinolyl-)-1,2-dihydroisoquinolin-1-one, was found to inhibit the growth of a PBEF1 over expressing glioma derived cell line U87 as well.
Thus, a novel inhibitor has been identified through a structure based drug discovery approach and is further supported by experimental evidence.
前B细胞集落增强因子1基因（PBEF1）编码烟酰胺磷酸核糖基转移酶（NMPRTase），该酶催化哺乳动物细胞中NAD+代谢补救途径的限速步骤。已显示胶质母细胞瘤中PBEF1转录本和蛋白质水平升高，并且已证明NMPRTase的化学抑制剂可特异性抑制癌细胞。
使用对接的虚拟筛选方法筛选了一个包含13000多种化合物的文库。通过NMPRTase酶测定法对入围的一组化合物进行体外抑制活性测试。此外，还测试了这些化合物抑制胶质瘤细胞增殖的能力。
虚拟筛选产生了34种可能的配体，其中6种通过NMPRTase酶抑制试验以及进一步的胶质瘤细胞活力试验进行了实验测试。其中，发现两种化合物在抑制烟酰胺转化为NAD+方面具有显著效果，其中一种化合物，即3-氨基-2-苄基-7-硝基-4-（2-喹啉基）-1,2-二氢异喹啉-1-酮，也被发现可抑制过表达PBEF1的胶质瘤衍生细胞系U87的生长。
因此，通过基于结构的药物发现方法鉴定了一种新型抑制剂，并得到了实验证据的进一步支持。
