title: Screening and biological evaluation of a novel STAT3 signaling pathway inhibitor against cancer.
abstract: It is now established that the specificity in signaling of signal transducer and activator of transcription 3 (STAT3) is mediated by the SH2 domain of STAT3, which mediates its interaction with the phosphopeptide docking sites displayed by receptors and JAKs, dimerization and subsequent DNA binding. Thus, we aimed to identify and design a class of strong potential small molecular inhibitors of STAT3 for the discovery and development of novel anticancer agents. Several classes of small molecules have been identified as STAT3 inhibitors after structure-based screening of the STAT3 SH2 domain. Next, we detected the activity of these inhibitors using fluorescence polarization (FP) and identified the growth inhibition of DU145 and MDA-MB-468 cells using the CCK-8 assay. Consequently, B9 inhibits the proliferation of tumor cells harboring abnormal activation of STAT3, such as, MDA-MB-468, MDA-MB-231 and DU145. However, there is little inhibition of MCF-7 cells. In addition, The Kdof B9 to STAT3 (I634S/Q635G) is 22.75μM compared to 4.59μM for WT as analyzed by SPR. The phosphorylation of STAT3 in MDA-MB-468 cells was obviously decreased after treatment with B9 at the preconceived concentration of 30μM, as detected using immunoblotting. Here, we evaluated the effect of B9 on the migration of MDA-MB-468 cells. Taken together, our results indicate a novel small molecule that decreases STAT3 activation and function of the STAT3 signaling pathway, thereby inducing an antitumor response in human breast cancer cells harboring constitutively active STAT3.
authors.affiliation: College of Pharmacy, Dalian Medical University, Dalian 116044, China; Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China.
authors.forename: Min
authors.initials: M
authors.lastname: Huang
authors.affiliation: College of Pharmacy, Dalian Medical University, Dalian 116044, China; Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China.
authors.forename: Zhongjie
authors.initials: Z
authors.lastname: Chen
authors.affiliation: College of Pharmacy, Dalian Medical University, Dalian 116044, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China.
authors.forename: Yiying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine, Shanghai 200025, China. Electronic address: jian.zhang@sjtu.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: College of Pharmacy, Dalian Medical University, Dalian 116044, China. Electronic address: xiaohong_shu@dlmedu.edu.cn.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Shu
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D009369:Neoplasms / Q000473:pathology*; D010766:Phosphorylation; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D020349:Surface Plasmon Resonance
chemical_list: D000970:Antineoplastic Agents; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human
keywords: Anticancer drug; Cancer; Inhibitor; SH2 domain; STAT3; Virtual screening