Differential clinical effects of different mutation subtypes in CALR-mutant myeloproliferative neoplasms.
Leukemia
; 30(2): 431-8, 2016 Feb.
Article
en En
| MEDLINE
| ID: mdl-26449662
ABSTRACT
A quarter of patients with essential thrombocythemia or primary myelofibrosis carry a driver mutation of CALR, the calreticulin gene. A 52-bp deletion (type 1) and a 5-bp insertion (type 2 mutation) are the most frequent variants. These indels might differentially impair the calcium binding activity of mutant calreticulin. We studied the relationship between mutation subtype and biological/clinical features of the disease. Thirty-two different types of CALR variants were identified in 311 patients. Based on their predicted effect on calreticulin C-terminal, mutations were classified as (i) type 1-like (65%); (ii) type 2-like (32%); and (iii) other types (3%). Corresponding CALR mutants had significantly different estimated isoelectric points. Patients with type 1 mutation, but not those with type 2, showed abnormal cytosolic calcium signals in cultured megakaryocytes. Type 1-like mutations were mainly associated with a myelofibrosis phenotype and a significantly higher risk of myelofibrotic transformation in essential thrombocythemia. Type 2-like CALR mutations were preferentially associated with an essential thrombocythemia phenotype, low risk of thrombosis despite very-high platelet counts and indolent clinical course. Thus, mutation subtype contributes to determining clinical phenotype and outcomes in CALR-mutant myeloproliferative neoplasms. CALR variants that markedly impair the calcium binding activity of mutant calreticulin are mainly associated with a myelofibrosis phenotype.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Calreticulina
/
Mielofibrosis Primaria
/
Trombocitemia Esencial
/
Mutación
Tipo de estudio:
Prognostic_studies
Límite:
Adolescent
/
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Año:
2016
Tipo del documento:
Article