Fiche publication
Date publication
mars 2015
Auteurs
Membres identifiés du Cancéropôle Est :
Pr NAMER Izzie-Jacques
Tous les auteurs :
Szarek E, Ball ER, Imperiale A, Tsokos M, Faucz FR, Giubellino A, Moussallieh FM, Namer IJ, Abu-Asab M, Pacak K, Taieb D, Carney A, Stratakis CA
Lien Pubmed
Résumé
Carney Triad(CTr) describes the association of paragangliomas(PGL), pulmonary chondromas, and gastrointestinal(GI) stromal tumors(GISTs) with a variety of other lesions including pheochromocytomas and adrenocortical tumors.The gene(s) causing CTr remain(s) unknown. PGL and GISTs may be caused by loss-of-function mutations in succinate dehydrogenase (SDH) (a condition known as Carney-Stratakis syndrome (CSS)). Mitochondrial structure and function are abnormal in tissues carrying SDH defects but they have not been studied in CTr. For this study, we examined mitochondrial structure in human tumors and GI tissue(GIT) of mice with SDH deficiency. Tissues from 16 CTr tumors (n=12), and those with isolated GIST(n=1), with CSS caused by SDHC(n=1), SDHD(n=2) mutations were studied by electron microscopy (EM).GIT from mice with a heterozygous deletion in Sdhb (Sdhb+/-,n=4) were also studied by EM.CTr patients presented with mostly epithelioid GISTs that were characterized by plump cells containing a centrally located round nucleus and prominent nucleoli; these changes were almost identical to those seen in the GIST of patients with SDH.In tumor cells from patients, regardless of diagnosis or tumor type, cytoplasm contained increased mitochondria with "hypoxic" phenotype: mitochondria were devoid of cristae, exhibited structural abnormalities and of variable size.Occasionally, mitochondria were small/round, rarely thin, elongated with tubular cristae. Many mitochondria exhibited amorphous fluffy material with membranous whorls or cystic structures. Similar mitochondrial hypoxic phenotype was seen in Sdhb+/- mice.We conclude tissues from SDH-deficient tumors and mouse GIT and from CTr tumors shared identical abnormalities in mitochondrial structure and other features.Thus, the still elusive CTr defect(s) is(are) likely to affect mitochondrial function just like germline SDH-deficiency.
Référence
Endocr Relat Cancer. 2015 Mar 25. pii: ERC-15-0069.