title: Characterization of HJ-PI01 as a novel Pim-2 inhibitor that induces apoptosis and autophagic cell death in triple-negative human breast cancer.
abstract: OBJECTIVE
  Pim-2 is a short-lived serine/threonine kinase, which plays a key role in metastasis of breast cancer through persistent activation of STAT3. Although the crystal structure of Pim-2 has been reported, but thus far no specific Pim-2-targeted compounds have been reported. In this study, we identified a novel Pim-2 inhibitor, HJ-PI01, by in silico analysis and experimental validation.
  
  
  METHODS
  The protein-protein interaction (PPI) network, chemical synthesis, molecular docking, and molecular dynamics (MD) simulations were used to design and discover the new Pim-2 inhibitor HJ-PI01. The anti-tumor effects of HJ-PI01 were evaluated in human breast MDA-MB-231, MDA-MB-468, MDA-MB-436, MCF-7 cells in vitro and in MDA-MB-231 xenograft mice, which were treated with HJ-PI01 (40 mg·kg(-1)·d(-1), ig) with or without lienal polypeptide (50 mg·kg(-1)·d(-1), ip) for 10 d. The apoptosis/autophage-inducing mechanisms of HJ-PI01 were elucidated using Western blots, immunoblots, flow cytometry, transmission electron microscopy and fluorescence microscopy.
  
  
  RESULTS
  Based on the PrePPI network, the potential partners interacting with Pim-2 in regulating apoptosis (160 protein pairs) and autophagy (47 protein pairs) were identified. Based on the structural characteristics of Pim-2, a total of 15 compounds (HJ-PI01 to HJ-P015) were synthesized, which showed moderate or remarkable anti-proliferative potency in the human breast cancer cell lines tested. The most effective compound HJ-PI01 exerted a robust inhibition on MDA-MB-231 cells compared with chlorpromazine and the pan-Pim inhibitor PI003. Molecular dynamics (MD) simulation revealed that HJ-PI01 had a good binding score with Pim-2. Moreover, HJ-PI01 (300 nmol/L) induced death receptor-dependent and mitochondrial apoptosis as well as autophagic death in MDA-MB-231 cells. In MDA-MB-231 xenograft mice, administration of HJ-PI01 remarkably inhibited the tumor growth and induced tumor cell apoptosis in vivo. Co-administration of HJ-PI01 with lienal polypeptide could improve the anti-tumor activity of HJ-PI01 and reduce its toxicity.
  
  
  CONCLUSIONS
  The newly synthesized compound, HJ-PI01, can induce death receptor/mitochondrial apoptosis and autophagic cell death by targeting Pim-2 in human breast cancer cells in vitro and in vivo.
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.
authors.forename: Yu-Qian
authors.initials: YQ
authors.lastname: Zhao
authors.affiliation: Department of Gastrointestinal Surgery, State Key Laboratory of Biotherapy, Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Yi-Qiong
authors.initials: YQ
authors.lastname: Yin
authors.affiliation: Department of Gastrointestinal Surgery, State Key Laboratory of Biotherapy, Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.
authors.forename: Gui-Hua
authors.initials: GH
authors.lastname: Wang
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.
authors.forename: Ling-Juan
authors.initials: LJ
authors.lastname: Zhu
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China.|School of Pharmacy, Shihezi University, Shihezi 832002, China.
authors.forename: Jin-Hui
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects*; D045744:Cell Line, Tumor; D015195:Drug Design; D005260:Female; D006801:Humans; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D010078:Oxazines / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D064726:Triple Negative Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; C000614913:HJ-PI01; D010078:Oxazines; C490587:PIM2 protein, human; D011518:Proto-Oncogene Proteins; D017346:Protein Serine-Threonine Kinases