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EGFR mutations cause a lethal syndrome of epithelial dysfunction with progeroid features.

Ganetzky R, Finn E, Bagchi A, Zollo O, Conlin L, Deardorff M, Harr M, Simpson MA, McGrath JA, Zackai E, Lemmon MA, Sondheimer N - Mol Genet Genomic Med (2015)

Bottom Line: The children were born prematurely, had abnormalities in skin and hair, suffered multisystem organ failure, and died in the neonatal period from intestinal perforation.EGF failed to induce mutated receptor phosphorylation in patient-derived fibroblasts and activation of downstream targets was suppressed.The heterologously expressed extracellular domain was impaired in stability and the binding of EGF.

View Article: PubMed Central - PubMed

Affiliation: Department of Pediatrics, The University of Pennsylvania Philadelphia, 19104, Pennsylvania ; Division of Genetics, The Children's Hospital of Philadelphia Philadelphia, 19104, Pennsylvania.

ABSTRACT
The epidermal growth factor receptor (EGFR) is part of a large family of receptors required for communicating extracellular signals through internal tyrosine kinases. Epidermal growth factor (EGF) signaling is required for tissue development, whereas constitutive activation of this signaling pathway is associated with oncogenic transformation. We identified homozygous c.1283G>A (p.Gly428Asp) mutations in the extracellular domain of EGFR in two siblings. The children were born prematurely, had abnormalities in skin and hair, suffered multisystem organ failure, and died in the neonatal period from intestinal perforation. EGF failed to induce mutated receptor phosphorylation in patient-derived fibroblasts and activation of downstream targets was suppressed. The heterologously expressed extracellular domain was impaired in stability and the binding of EGF. Cells from the affected patient undergo early senescence with accelerated expression of β-galactosidase and shortened telomeres at all passages when compared to controls. A comparison of homozygous inherited regions from a separate report of a patient from the same ethnic background and EGFR genotype confirms the pathogenicity of EGFR mutations in congenital disease.

No MeSH data available.


Related in: MedlinePlus

Western blot shows higher levels of EGFR in control compared to patient samples, and higher levels of p-EGFR following EGF stimulation in controls samples, as compared to patients (A). Addition of the EGFR kinase inhibitor gefitinib eliminates EGFR phosphorylation following EGF stimulation and does not change overall EGFR levels (B). Levels of EGFR are decreased at 30 and 90 min following EGF stimulation in control cells, but are unchanged at the same time points in patient cells (C).
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fig03: Western blot shows higher levels of EGFR in control compared to patient samples, and higher levels of p-EGFR following EGF stimulation in controls samples, as compared to patients (A). Addition of the EGFR kinase inhibitor gefitinib eliminates EGFR phosphorylation following EGF stimulation and does not change overall EGFR levels (B). Levels of EGFR are decreased at 30 and 90 min following EGF stimulation in control cells, but are unchanged at the same time points in patient cells (C).

Mentions: To evaluate levels of EGFR expression and ligand-induced activation, we probed western blots of cell lysates with antibodies against EGFR and phospho-EGFR. EGFR levels in the patient-derived cell line were substantially reduced in comparison to an unaffected control (Fig.3A, top). Tyrosine autophosphorylation of EGFR in response to EGF or serum addition was robust in control cells. (Fig.3A, bottom). but could not be detected in patient-derived samples. This suggests that both the level and activity of EGFRGly428Asp are strongly impaired. To confirm that the observed phosphorylation in control cells was EGFR-specific, we repeated the experiment in the presence of the EGFR inhibitor gefitinib, which entirely inhibited phosphorylation in the control cells and lacked any effect in the patient sample (Fig.3B).


EGFR mutations cause a lethal syndrome of epithelial dysfunction with progeroid features.

Ganetzky R, Finn E, Bagchi A, Zollo O, Conlin L, Deardorff M, Harr M, Simpson MA, McGrath JA, Zackai E, Lemmon MA, Sondheimer N - Mol Genet Genomic Med (2015)

Western blot shows higher levels of EGFR in control compared to patient samples, and higher levels of p-EGFR following EGF stimulation in controls samples, as compared to patients (A). Addition of the EGFR kinase inhibitor gefitinib eliminates EGFR phosphorylation following EGF stimulation and does not change overall EGFR levels (B). Levels of EGFR are decreased at 30 and 90 min following EGF stimulation in control cells, but are unchanged at the same time points in patient cells (C).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4585453&req=5

fig03: Western blot shows higher levels of EGFR in control compared to patient samples, and higher levels of p-EGFR following EGF stimulation in controls samples, as compared to patients (A). Addition of the EGFR kinase inhibitor gefitinib eliminates EGFR phosphorylation following EGF stimulation and does not change overall EGFR levels (B). Levels of EGFR are decreased at 30 and 90 min following EGF stimulation in control cells, but are unchanged at the same time points in patient cells (C).
Mentions: To evaluate levels of EGFR expression and ligand-induced activation, we probed western blots of cell lysates with antibodies against EGFR and phospho-EGFR. EGFR levels in the patient-derived cell line were substantially reduced in comparison to an unaffected control (Fig.3A, top). Tyrosine autophosphorylation of EGFR in response to EGF or serum addition was robust in control cells. (Fig.3A, bottom). but could not be detected in patient-derived samples. This suggests that both the level and activity of EGFRGly428Asp are strongly impaired. To confirm that the observed phosphorylation in control cells was EGFR-specific, we repeated the experiment in the presence of the EGFR inhibitor gefitinib, which entirely inhibited phosphorylation in the control cells and lacked any effect in the patient sample (Fig.3B).

Bottom Line: The children were born prematurely, had abnormalities in skin and hair, suffered multisystem organ failure, and died in the neonatal period from intestinal perforation.EGF failed to induce mutated receptor phosphorylation in patient-derived fibroblasts and activation of downstream targets was suppressed.The heterologously expressed extracellular domain was impaired in stability and the binding of EGF.

View Article: PubMed Central - PubMed

Affiliation: Department of Pediatrics, The University of Pennsylvania Philadelphia, 19104, Pennsylvania ; Division of Genetics, The Children's Hospital of Philadelphia Philadelphia, 19104, Pennsylvania.

ABSTRACT
The epidermal growth factor receptor (EGFR) is part of a large family of receptors required for communicating extracellular signals through internal tyrosine kinases. Epidermal growth factor (EGF) signaling is required for tissue development, whereas constitutive activation of this signaling pathway is associated with oncogenic transformation. We identified homozygous c.1283G>A (p.Gly428Asp) mutations in the extracellular domain of EGFR in two siblings. The children were born prematurely, had abnormalities in skin and hair, suffered multisystem organ failure, and died in the neonatal period from intestinal perforation. EGF failed to induce mutated receptor phosphorylation in patient-derived fibroblasts and activation of downstream targets was suppressed. The heterologously expressed extracellular domain was impaired in stability and the binding of EGF. Cells from the affected patient undergo early senescence with accelerated expression of β-galactosidase and shortened telomeres at all passages when compared to controls. A comparison of homozygous inherited regions from a separate report of a patient from the same ethnic background and EGFR genotype confirms the pathogenicity of EGFR mutations in congenital disease.

No MeSH data available.


Related in: MedlinePlus