Multiple giant cell lesions in patients with Noonan syndrome and cardio-facio-cutaneous syndrome.
Noonan syndrome (NS) and cardio-facio-cutaneous syndrome (CFCS) are related developmental disorders caused by mutations in genes encoding various components of the RAS-MAPK signaling cascade. NS is associated with mutations in the genes PTPN11, SOS1, RAF1, or KRAS, whereas CFCS can be caused by mutations in BRAF, MEK1, MEK2, or KRAS. The NS phenotype is rarely accompanied by multiple giant cell lesions (MGCL) of the jaw (Noonan-like/MGCL syndrome (NL/MGCLS)). PTPN11 mutations are the only genetic abnormalities reported so far in some patients with NL/MGCLS and in one individual with LEOPARD syndrome and MGCL. In a cohort of 75 NS patients previously tested negative for mutations in PTPN11 and KRAS, we detected SOS1 mutations in 11 individuals, four of whom had MGCL. To explore further the relevance of aberrant RAS-MAPK signaling in syndromic MGCL, we analyzed the established genes causing CFCS in three subjects with MGCL associated with a phenotype fitting CFCS. Mutations in BRAF or MEK1 were identified in these patients. All mutations detected in these seven patients with syndromic MGCL had previously been described in NS or CFCS without apparent MGCL. This study demonstrates that MGCL may occur in NS and CFCS with various underlying genetic alterations and no obvious genotype-phenotype correlation. This suggests that dysregulation of the RAS-MAPK pathway represents the common and basic molecular event predisposing to giant cell lesion formation in patients with NS and CFCS rather than specific mutation effects.
1Department of Human Genetics, University Hospital Münster, Münster, Germany.
Thomas E
TE
Neumann
Judith
J
Allanson
Ines
I
Kavamura
Bronwyn
B
Kerr
Giovanni
G
Neri
Jacqueline
J
Noonan
Viviana
V
Cordeddu
Kate
K
Gibson
Andreas
A
Tzschach
Gabriele
G
Krüger
Maria
M
Hoeltzenbein
Timm O
TO
Goecke
Hans Gerd
HG
Kehl
Beate
B
Albrecht
Klaudiusz
K
Luczak
Maria M
MM
Sasiadek
Luciana
L
Musante
Rohan
R
Laurie
Hartmut
H
Peters
Marco
M
Tartaglia
Martin
M
Zenker
Vera
V
Kalscheuer
D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D005260:Female; D015726:Giant Cells / Q000473:pathology*; D006331:Heart Diseases / Q000151:congenital / Q000473:pathology; D006801:Humans; D020935:MAP Kinase Signaling System / Q000235:genetics; D008297:Male; D009154:Mutation; D009634:Noonan Syndrome / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D010641:Phenotype; D012871:Skin Diseases / Q000473:pathology; D013577:Syndrome; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism
D018631:ras Proteins