title: Erythropoietin protects neuroblastoma cells against etoposide and vincristine by activating ERK and AKT pathways but has no effect in kidney cells.
abstract: OBJECTIVE
  Chemotherapy induces anaemia in neuroblastoma patients. Cancer-associated anaemia may be treated with recombinant erythropoietin. However, the potential effects of erythropoietin on neuroblastoma and kidney cells have not been extensively evaluated. The present study was designed to investigate the effect of erythropoietin on the proliferation, and protection against vincristine- and etoposide-induced cell death in neuroblastoma (MSN), and embryonic kidney (HEK 293) cells.
  
  
  METHODS
  The expression of erythropoietin and its receptor in MSN and HEK 293 was analysed by RT-PCR, immunocytochemistry, and Western blotting. The effect of erythropoietin on cell viability and proliferation was evaluated by the MTT assay, and by the Click-iT EdU Alexa Fluor 647 kit, respectively. For the cyto-protective assays, cells were incubated with erythropoietin before etoposide and vincristine treatment. Activation of signalling pathways was studied by Western blotting.
  
  
  RESULTS
  MSN and HEK 293 cells expressed the erythropoietin receptor, but not erythropoietin. Erythropoietin induced proliferation and protection against vincristine and etoposide in MSN cells. HEK 293 cells were not affected by erythropoietin. Erythropoietin showed an anti-apoptotic effect which was dependent on the activation of ERK1/2 and AKT. HEK 293 cells presented constitutively phosphorylated AKT, and showed no activation of ERK1/2 upon erythropoietin stimulation.
  
  
  CONCLUSIONS
  These results indicate that erythropoietin induces proliferation of MSN cells, and that it can ameliorate vincristine- and etoposide-induced apoptosis of these cells. Erythropoietin-mediated neuroprotection was regulated by the combined effect of the ERK1/2 and AKT signalling pathways. Our findings provide further insights into the potential effect of erythropoietin on neuroblastoma cells.
authors.affiliation: Departamento de Biología Molecular y Biotencología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, D.F. CP 04510, Mexico; Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Unidad de Posgrado, Edificio B Primer Piso, Ciudad Universitaria, México, D.F. CP 04510, Mexico.
authors.forename: Maria Jose
authors.initials: MJ
authors.lastname: Vazquez-Mellado
authors.affiliation: Departamento de Biología Molecular y Biotencología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, D.F. CP 04510, Mexico.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Aguilar
authors.affiliation: Departamento de Biología Molecular y Biotencología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, D.F. CP 04510, Mexico. Electronic address: lrochaz@biomedicas.unam.mx.
authors.forename: Leticia
authors.initials: L
authors.lastname: Rocha-Zavaleta
mesh_terms: D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004921:Erythropoietin / Q000096:biosynthesis / Q000494:pharmacology*; D005047:Etoposide / Q000009:adverse effects*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000187:drug effects; D009447:Neuroblastoma / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D020011:Protective Agents / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017467:Receptors, Erythropoietin / Q000096:biosynthesis; D015398:Signal Transduction / Q000187:drug effects*; D014750:Vincristine / Q000009:adverse effects*
chemical_list: D020011:Protective Agents; D017467:Receptors, Erythropoietin; D004921:Erythropoietin; D014750:Vincristine; D005047:Etoposide; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases
keywords: Erythropoietin; Etoposide; Neuroblastoma; Neuroprotection; Vincristine