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Updated: Jul 9, 2026

Using CRISPR/Cas9 Gene Editing to Investigate the Oncogenic Activity of Mutant Calreticulin in Cytokine Dependent Hematopoietic Cells
10:21

Using CRISPR/Cas9 Gene Editing to Investigate the Oncogenic Activity of Mutant Calreticulin in Cytokine Dependent Hematopoietic Cells

Published on: January 5, 2018

Protective role of calreticulin in HFE hemochromatosis

Jorge P Pinto1, Pedro Ramos, Sérgio F de Almeida

  • 1Iron Genes and Immune System, Instituto de Biologia Molecular e Celular, Universidade do Porto, 4150-180 Porto, Portugal.

Free Radical Biology & Medicine
|November 30, 2007
PubMed

HFE gene mutations are associated with over 80% of cases of hereditary hemochromatosis (HH), an iron-overload disease in which the liver is the most frequently affected organ. Research on HFE has traditionally focused on its interaction with the transferrin receptor. More recent studies have suggested a more complex function for this nonclassical MHC-I protein. The aim of this study was to examine how HFE and its two most common mutations affect the expression of selected genes in a hepatocyte-like cell line. Gene expression was analyzed in HepG2 cells overexpressing wild-type and mutant HFE. The effect of HFE in iron import and oxidative stress levels was assessed. Unfolded protein response (UPR)-activated gene expression was analyzed in peripheral blood mononuclear cells from characterized HH patients. C282Y HFE down-regulated hepcidin and enhanced calreticulin mRNA expression. Calreticulin levels correlated with intracellular iron increase and were associated with protection from oxidative stress. In C282Y(+/+) patients calreticulin levels correlated with the expression of the UPR marker BiP and showed a negative association with the number of hereditary hemochromatosis clinical manifestations. The data show that expression of C282Y HFE triggers a stress-protective response in HepG2 cells and suggest a role for calreticulin as a modifier of the clinical expression of HH.

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