title: [Effect of cryotherapy over the expression of vascular endothelial growth factor and pigment epithelium-derived factor].
abstract: BACKGROUND
  Cryotherapy is a no invasive technique that uses intense cold to freeze and destroy cancer tissues. There are no descriptions of its effects over the expression of vascular endothelial growth factor and pigment epithelium-derived factor.
  
  
  METHODS
  Experimental study in cryogenic spot were applied in the right sclera of twelve pigs for ten minutes. Other 3 pigs were used as normal controls. Animals were sacrificed at 7, 14 and 21 and the tissues of choriodes and retina were dissected in areas of approximately 1 cm2 surrounding cryogenic spots. Expression levels of vascular endothelial growth factor and pigment epithelium-derived factor were determined analyzed using polymerase chain reaction coupled to reverse-transcription.
  
  
  RESULTS
  Vascular endothelial growth factor was significantly downregulated (24%, p< 0.05) seven days post-treatment meanwhile pigment epithelium-derived factor levels increased 44.8% (p< 0.05) as compared to normal controls (untreated). Both vascular endothelial growth factor and pigment epithelium-derived factor levels remain the same until day 14 but returned to basal expression at day 21.
  
  
  CONCLUSIONS
  This work expose the relation of cryotherapy with the expression of two factors related to angiogenesis. RESULTS showed significant changes on the expression of vascular endothelial growth factor and pigment epithelium-derived factor illustrating that both proteins are regulated in response to cryogenic treatment in relatively short periods (21 days).
authors.affiliation: Dirección de Investigación, Hospital Juárez de México, México DF.
authors.forename: Julia Dolores
authors.initials: JD
authors.lastname: Toscano-Garibay
authors.affiliation: Denver Health Medical Center-Vision Center, Davis Pavilion-North Tower, Denver, Colorado, United States.
authors.forename: Hugo
authors.initials: H
authors.lastname: Quiroz-Mercado
authors.affiliation: Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, Mexico.
authors.forename: Clara
authors.initials: C
authors.lastname: Espitia-Pinzón
authors.affiliation: Asociación para Evitar la Ceguera en México, Institución de Asistencia Privada. Dr. Lui Sánchez Bulnes, México DF, Mexico.
authors.forename: Félix
authors.initials: F
authors.lastname: Gil-Carrasco
authors.affiliation: Dirección de Investigación, Hospital Juárez de México, México DF, Mexico. javier_70_1999@yahoo.com.
authors.forename: José Javier
authors.initials: JJ
authors.lastname: Flores-Estrada
mesh_terms: D000818:Animals; D017209:Apoptosis; D002829:Choroid / Q000378:metabolism; D020256:Choroidal Neovascularization / Q000209:etiology / Q000235:genetics*; D017679:Cryotherapy; D004730:Endothelium, Vascular / Q000378:metabolism; D005136:Eye Proteins / Q000096:biosynthesis* / Q000235:genetics; D005786:Gene Expression Regulation; D009414:Nerve Growth Factors / Q000096:biosynthesis* / Q000235:genetics; D012160:Retina / Q000378:metabolism; D015861:Retinal Neovascularization / Q000209:etiology / Q000235:genetics*; D012590:Sclera / Q000378:metabolism*; D015843:Serpins / Q000096:biosynthesis* / Q000235:genetics; D034421:Sus scrofa; D013552:Swine; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis* / Q000235:genetics; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D005136:Eye Proteins; D009414:Nerve Growth Factors; D015843:Serpins; D042461:Vascular Endothelial Growth Factor A; D000099174:Pigment Epithelium-Derived Factor
keywords: Vascular endothelial growth factor; crioterapia; cryotherapy; factor de crecimiento del endotelio vascular; factor derivado del epitelio pigmentado; pigment-epithelium derived factor