title: Cytosine arabinoside induces ectoderm and inhibits mesoderm expression in human embryonic stem cells during multilineage differentiation.
abstract: OBJECTIVE
  Teratogenic substances induce adverse effects during the development of the embryo. Multilineage differentiation of human embryonic stem cells (hESCs) mimics the development of the embryo in vitro. Here, we propose a transcriptomic approach in hESCs for monitoring specific toxic effects of compounds as an alternative to traditional time-consuming and cost-intensive in vivo tests requiring large numbers of animals. This study was undertaken to explore the adverse effects of cytosine arabinoside (Ara-C) on randomly differentiated hESCs.
  
  
  METHODS
  Human embryonic stem cells were used to investigate the effects of a developmental toxicant Ara-C. Sublethal concentrations of Ara-C were given for two time points, day 7 and day 14 during the differentiation. Gene expression was assessed with microarrays to determine the dysregulated transcripts in presence of Ara-C.
  
  
  RESULTS
  Randomly differentiated hESCs were able to generate the multilineage markers. The low concentration of Ara-C (1 nM) induced the ectoderm and inhibited the mesoderm at day 14. The induction of ectodermal markers such as MAP2, TUBB III, PAX6, TH and NESTIN was observed with an inhibition of mesodermal markers such as HAND2, PITX2, GATA5, MYL4, TNNT2, COL1A1 and COL1A2. In addition, no induction of apoptosis was observed. Gene ontology revealed unique dysregulated biological process related to neuronal differentiation and mesoderm development. Pathway analysis showed the axon guidance pathway to be dysregulated.
  
  
  CONCLUSIONS
  Our results suggest that hESCs in combination with toxicogenomics offer a sensitive in vitro developmental toxicity model as an alternative to traditional animal experiments.
authors.affiliation: Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Jagtap
authors.forename: K
authors.initials: K
authors.lastname: Meganathan
authors.forename: J
authors.initials: J
authors.lastname: Gaspar
authors.forename: V
authors.initials: V
authors.lastname: Wagh
authors.forename: J
authors.initials: J
authors.lastname: Winkler
authors.forename: J
authors.initials: J
authors.lastname: Hescheler
authors.forename: A
authors.initials: A
authors.lastname: Sachinidis
mesh_terms: D000826:Animal Testing Alternatives / Q000379:methods; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000633:toxicity*; D002454:Cell Differentiation / Q000187:drug effects*; D003561:Cytarabine / Q000008:administration & dosage / Q000633:toxicity*; D004475:Ectoderm / Q000187:drug effects / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000187:drug effects* / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D008648:Mesoderm / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D013997:Time Factors
chemical_list: D000964:Antimetabolites, Antineoplastic; D003561:Cytarabine