title: Impact of kinesin Eg5 inhibition by 3,4-dihydropyrimidin-2(1H)-one derivatives on various breast cancer cell features.
abstract: BACKGROUND
  Breast cancer is a complex heterogeneous disease and is one of the leading causes of death among women. In addressing the need for treatments of this life-threatening illness, we studied 3,4-dihydropyrimidin-2(1H)-one (or thione) derivatives (DHPMs), a class of inhibitor molecules of the Eg5 motor spindle protein that shows pronounced antitumor activity against several cancer cell lines.
  
  
  METHODS
  An in vitro screening was performed for identification of DHPMs with potent antitumor effects on MCF-7 and MDA-MB-231 cells and the selected DHPMs were evaluated for their inhibitory activity on Eg5 both in silico, using Molecular dynamics, and in vitro Eg5 inhibition assays. Analysis of cell death induction, proliferation, cell cycle and cancer stem cells (CSC) profile were performed by flow cytometry to assess the influence of the selected DPHMs on these important tumor features. Finally, the effects of DHPM treatment on tube formation were evaluated in vitro using HUVEC cells, and in vivo using a model on chorioallantoic membrane (CAM) of fertilized eggs.
  
  
  RESULTS
  We identified five DHPMs with pronounced inhibitory activity on Eg5 motor protein interfering with the proper mitotic spindle assembly during cell division. These compounds impair the correct conclusion of cell cycle of the breast cancer cells and showed to be selective for tumor cells. Moreover, DHPMs modulate the CD44(+)/CD24(-) phenotype leading to a decrease in the CSC population in MDA-MB-231 cells, an important effect since CSC are resistant to many conventional cancer therapies and play a pivotal role in tumor initiation and maintenance. This observation was confirmed by the results which demonstrated that DHPM treated cells had impaired proliferation and were unable to sustain angiogenesis events. Finally, the DHMP treated cells were induced to apoptosis, which is one of the most pursued goals in drug development.
  
  
  CONCLUSIONS
  The results of our study strongly suggest that DHPMs inhibit important tumorigenic features of breast cancer cells leading them to death by apoptosis. These findings firmly point to DHPM molecular architecture as a promising alternative against breast cancer.
authors.affiliation: Department of Cell Biology, Laboratory of Electron Microscopy, University of Brasília (IB-UnB), Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil. brunacguido@gmail.com.
authors.forename: Bruna C
authors.initials: BC
authors.lastname: Guido
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Brasília, Distrito Federal, Brazil. lucianamramos@hotmail.com.
authors.forename: Luciana M
authors.initials: LM
authors.lastname: Ramos
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA. nolasco@mit.edu.|Physics Course, Catholic University of Brasília, Brasília, Distrito Federal, Brazil. nolasco@mit.edu.
authors.forename: Diego O
authors.initials: DO
authors.lastname: Nolasco
authors.affiliation: Department of Cell Biology, Laboratory of Electron Microscopy, University of Brasília (IB-UnB), Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil. catharine_carrara@hotmail.com.
authors.forename: Catharine C
authors.initials: CC
authors.lastname: Nobrega
authors.affiliation: Department of Cell Biology, Laboratory of Electron Microscopy, University of Brasília (IB-UnB), Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil. barbarayasmi@gmail.com.
authors.forename: Bárbara Y G
authors.initials: BY
authors.lastname: Andrade
authors.affiliation: Laboratory of Embryology and Developmental Biology, Genetics and Morphology Department, University of Brasília (IB-UnB), Brasília, Distrito Federal, Brazil. alinepic@unb.br.
authors.forename: Aline
authors.initials: A
authors.lastname: Pic-Taylor
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Brasília, Distrito Federal, Brazil. brenno.ipi@gmail.com.
authors.forename: Brenno A D
authors.initials: BA
authors.lastname: Neto
authors.affiliation: Department of Cell Biology, Laboratory of Electron Microscopy, University of Brasília (IB-UnB), Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil. correa@unb.br.
authors.forename: José R
authors.initials: JR
authors.lastname: Corrêa
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D006801:Humans; D020128:Inhibitory Concentration 50; D016547:Kinesins / Q000037:antagonists & inhibitors* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism; D009389:Neovascularization, Pathologic; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; C470243:KIF11 protein, human; D011743:Pyrimidines; D016547:Kinesins