EZH2 mutation in an adolescent with Weaver syndrome developing acute myeloid leukemia and secondary hemophagocytic lymphohistiocytosis

Am J Med Genet A. 2016 May;170A(5):1274-7. doi: 10.1002/ajmg.a.37562. Epub 2016 Jan 14.

Abstract

Weaver syndrome is an overgrowth syndrome characterized by pre- and postnatal overgrowth with distinctive craniofacial appearance. Mutations in the enhancer of zeste homolog 2 (EZH2) gene were found to cause Weaver syndrome, and have been associated with hematologic malignancies, including acute myeloid leukemia (AML). We present the first report of a patient with Weaver syndrome, who developed AML and harbored an EZH2 mutation. The clinical course of the 16-year-old female adolescent patient was complicated by a secondary hemophagocytic lymphohistiocytosis. Genomic DNA was isolated from bone marrow cells at AML diagnosis. Polymerase chain reactions were performed with primers covering all exons of the EZH2 gene. We found a novel heterozygous EZH2 mutation within exon 5 that caused an amino acid change from proline to leucine at position 132 (p.Pro132Leu) within the catalytic D1 domain. Analysis of a remission sample also showed this mutation, indicating a germline mutation. It remains to be elucidated whether EZH2 mutations contribute to disease severity in specific AML cases.

Keywords: EZH2; Weaver syndrome; acute myeloid leukemia; hemophagocytic lymphohistiocytosis; malignancy; overgrowth.

Publication types

  • Case Reports

MeSH terms

  • Abnormalities, Multiple / genetics*
  • Abnormalities, Multiple / physiopathology
  • Adolescent
  • Amino Acid Substitution / genetics
  • Congenital Hypothyroidism / complications
  • Congenital Hypothyroidism / genetics*
  • Congenital Hypothyroidism / physiopathology
  • Craniofacial Abnormalities / complications
  • Craniofacial Abnormalities / genetics*
  • Craniofacial Abnormalities / physiopathology
  • Enhancer of Zeste Homolog 2 Protein / genetics*
  • Female
  • Hand Deformities, Congenital / complications
  • Hand Deformities, Congenital / genetics*
  • Hand Deformities, Congenital / physiopathology
  • Humans
  • Leukemia, Myeloid, Acute / complications
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / physiopathology
  • Lymphohistiocytosis, Hemophagocytic / complications
  • Lymphohistiocytosis, Hemophagocytic / genetics*
  • Lymphohistiocytosis, Hemophagocytic / physiopathology

Substances

  • EZH2 protein, human
  • Enhancer of Zeste Homolog 2 Protein

Supplementary concepts

  • Weaver syndrome