Childhood solid tumours

Gene: FBXW7

Amber List (moderate evidence)

FBXW7 (F-box and WD repeat domain containing 7)
EnsemblGeneIds (GRCh38): ENSG00000109670
EnsemblGeneIds (GRCh37): ENSG00000109670
OMIM: 606278, Gene2Phenotype
FBXW7 is in 4 panels

2 reviews

Arina Puzriakova (Genomics England Curator)

Comment on list classification: Rating Amber as at present I do not think there is enough evidence to classify this as a diagnostic-grade cancer gene.

There are previous reports of dn/inh germline variants in individuals (likely 7) with tumor predisposition, two had structural alternations that affected other genomic regions and the others were identified from a targeted Wilms cohort.
FBXW7 heterozygous variants have also been associated with a neurodevelopmental disorder (OMIM:620012; G2P - moderate) but these individuals not shown malignancy. FBXW7 is not linked to a cancer phenotype in OMIM or G2P.
Nonetheless this is a tumour suppressor gene that is worth monitoring for new evidence linking to cancer susceptibility (added watchlist tag).
Created: 24 Jul 2023, 11:06 a.m. | Last Modified: 24 Jul 2023, 11:06 a.m.
Panel Version: 4.5
Partially copied review from Konstantinos Varvagiannis on the Intellectual disability panel (v5.0):

"Finally, as the authors comment, FBXW7 is a tumor suppressor among the most commonly mutated genes in human cancer (3.5%). Germline variants have been previously reported in individuals with cancer (Wilms tumor, rhabdoid, etc - most summarized below). However, none of the 35 individuals in this cohort (oldest 44 y.o.) had any history of cancer (PMID: 35395208).

Reports of individuals with germline variants causing (monoallelic) disruption of FBXW7 - cases without DD/ID:

[3]------------
Mahamdallie et al (2019 - PMID: 30885698) investigated with WES a cohort of 890 individuals with Wilms tumor (799 non-familial disease, 91 from WT pedigrees). In this context they identified 4 individuals having developed WT (ages: 28-76m) with FBXW7 dn or inherited LoF variants (710G>A / p.Trp237* dn - 1972C>T / p.Arg658* - inh:NA, 1017_1021del5, 670C>T - paternal / p.Arg224* inh:NA - RefSeq not provided). One additional individual with a missense variant (1753A>T / p.Ser585Cys - dn) had developed rhabdoid tumor. While the authors mentioned additional features for other subjects in their cohort, among the 5 individuals with FBXW7 variants, only one had hypotonia (ID_0592) and another (ID_7520) had two febrile convulsions.

[4]------------
Roversi et al (2015 - PMID: 26482194) described the phenotype of a 34 y.o. female with syndromic presentation (macrocephaly, nephrotic syndrome due to FSGS, Hodgkin's lymphoma, Wilms tumor, ovarian cystadenoma, breast carcinoma) harboring a 157 kb deletion of 4q31.3.

Eventual DD/ID was not reported despite detailed clinical description.

The deletion spanned almost the entire FBXW7 gene and a pseudogene (hg19 - chr4:153205202-153362047). The authors provided evidence that the del affected the maternal allele as dn event (maternal mosaicism excluded). Expression of FBXW7 in patient-derived EBV lymphoblastoid cell line revealed decreased levels of expression compared to controls. At somatic level, the authors looked for eventual 2nd hit in tumor tissue (which was not the case) while they demonstrated decreased FBXW7 expression in a WT sample compared to normal renal tissue. Previously, variants in other genes candidate for the phenotype were ruled out (Sanger & MLPA for TP53, BRCA1/2, PALB2, WT1, 11p15 MS-MLPA, std karyotype).

[5]------------
Kuiper et al (2015 - PMID: 19963109), in a 58 y.o. patient with recurrence of RCC, identified a constitutional translocation [t(3;4)(q21;q31)]. Using long-range PCR they defined the breakpoints at 3q21.3 (128379059 - hg18) between the PLXNA1 and C3orf56 genes while the chr4 breakpoint was located within the second intron of FBXW7 (pos. 153500813 - hg18). There were no additional phenotypes reported.

[6]------------
Williams et al (2010 - PMID: 20332316) reported a patient with WT harboring germline variants in WT1 and FBXW7. While the phenotype was sufficiently explained by a germline stopgain WT1 variant with a frameshift WT1 variant (as 2nd hit) confined to the tumor, the authors identified a germline in-frame FBXW7 insertion in the same individual (c.45_46insCCT / p.Thr15_Gly16insPro - RefS : NA) [if correct corresponding to: https://gnomad.broadinstitute.org/variant/4-153332910-C-CAGG - 345/281696 alleles in gnomAD]."
Created: 24 Jul 2023, 10:22 a.m. | Last Modified: 24 Jul 2023, 10:22 a.m.
Panel Version: 4.2

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown

Publications

Dmitrijs Rots (Children's Clinical University Hospital)

Green List (high evidence)

In 30885698 five cases with de novo and truncating variants and childhood tumors are reported. Gene is intolerant to truncating variants (pLI=1). Enough evidence for green rating.
Sources: Literature
Created: 17 May 2023, 6:08 p.m.

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Developmental delay, hypotonia, and impaired language

Publications

Details

Mode of Inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Sources
  • Expert Review Amber
Phenotypes
  • Wilms tumor, MONDO:0006058
  • Rhabdoid tumor, MONDO:0002728
Tags
watchlist
OMIM
606278
Clinvar variants
Variants in FBXW7
Penetrance
Incomplete
Publications
Panels with this gene

History Filter Activity

24 Jul 2023, Gel status: 2

Entity classified by Genomics England curator

Arina Puzriakova (Genomics England Curator)

Gene: fbxw7 has been classified as Amber List (Moderate Evidence).

24 Jul 2023, Gel status: 0

Set Phenotypes

Arina Puzriakova (Genomics England Curator)

Phenotypes for gene: FBXW7 were changed from Developmental delay, hypotonia, and impaired language to Wilms tumor, MONDO:0006058; Rhabdoid tumor, MONDO:0002728

24 Jul 2023, Gel status: 0

Set publications

Arina Puzriakova (Genomics England Curator)

Publications for gene: FBXW7 were set to 30885698

24 Jul 2023, Gel status: 0

Added Tag

Arina Puzriakova (Genomics England Curator)

Tag watchlist tag was added to gene: FBXW7.

17 May 2023, Gel status: 0

Created, Added New Source, Set mode of inheritance, Set publications, Set Phenotypes, Set penetrance

Dmitrijs Rots (Children's Clinical University Hospital)

gene: FBXW7 was added gene: FBXW7 was added to Childhood solid tumours. Sources: Literature Mode of inheritance for gene: FBXW7 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: FBXW7 were set to 30885698 Phenotypes for gene: FBXW7 were set to Developmental delay, hypotonia, and impaired language Penetrance for gene: FBXW7 were set to Incomplete Review for gene: FBXW7 was set to GREEN