title: Hemin induces mitophagy in a leukemic erythroblast cell line.
abstract: BACKGROUND
  In eukaryotic cells, autophagy is considered a lysosomal catabolic process which participates in the degradation of intracellular components in a vacuolar structure termed autolysosome. This pathway plays a significant role in the erythropoiesis process, contributing to the clearance of some organelles (such as mitochondria) that are not necessary in the mature red blood cells. Nevertheless, the role of autophagy in erythrocyte maturation has not been fully established.
  
  
  RESULTS
  Here, we have demonstrated that hemin (a physiological erythroid maturation stimulator) is able to induce the expression of critical autophagic genes (i.e., Map1a1b (LC3), Beclin-1 gen, Atg5) in an erythroleukemia cell type. We have also shown that hemin increased the size of autophagic vacuoles which were labelled with LC3 and the degradative lysosomal marker dye quenched-bovine serum albumin. In addition, we have determined by Western blot a rise in the lipidated form of the autophagic protein LC3 (i.e., LC3-II) upon hemin treatment. Moreover, we provide evidence that hemin induces mitochondrial membrane depolarisation and that mitochondria sequestration by autophagy requires the active form of the NIX protein.
  
  
  CONCLUSIONS
  We have found that the physiological erythroid maturation stimulator hemin is able to induce mitophagy in K562 cells, and that the autophagy adaptor NIX is necessary for mitophagy progression. K562 cells have been used as a relevant model to determine the possible therapeutic role of new differentiating compounds.
  
  
  CONCLUSIONS
  It has been proposed that autophagy induction is a feasible new therapeutic key in fighting cancer. Our results suggest that hemin is favoring erythroid maturation by inducing an autophagic response in K562 cells, being a possible therapeutic candidate that may help in the chronic myelogenous leukemia (CML) treatment.
authors.affiliation: Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza, Argentina.|Instituto de Histología y Embriología (IHEM), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina.
authors.forename: Claudio Marcelo
authors.initials: CM
authors.lastname: Fader
authors.affiliation: Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza, Argentina.
authors.forename: Betiana Nebaí
authors.initials: BN
authors.lastname: Salassa
authors.affiliation: Instituto de Histología y Embriología (IHEM), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina.
authors.forename: Rubén Adrián
authors.initials: RA
authors.lastname: Grosso
authors.affiliation: Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza, Argentina.
authors.forename: Agustín Nicolás
authors.initials: AN
authors.lastname: Vergara
authors.affiliation: Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza, Argentina.|Instituto de Histología y Embriología (IHEM), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Colombo
mesh_terms: D015973:Gene Expression Regulation, Leukemic; D006427:Hemin / Q000378:metabolism*; D006801:Humans; D020014:K562 Cells; D004915:Leukemia, Erythroblastic, Acute / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D063306:Mitophagy; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C116838:BNIP3L protein, human; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D025521:Tumor Suppressor Proteins; D006427:Hemin
keywords: Autophagy; Erythroid maturation; Hemin; K562; LC3