SMARCB1

(redirected from INI1)

SMARCB1

A gene on chromosome 22q11.23 that encodes a core component of the ATP-dependent chromatin-remodelling BAF (hSWI/SNF) complex, which plays key roles in cell proliferation and differentiation and has antiviral and anti-tumour activity.

Molecular pathology
Defects in SMARCB1 rhabdoid tumour predisposition syndrome type 1, schwannomatosis and mental retardation, autosomal dominant type 1.
References in periodicals archive ?
Also, loss of INI1 is helpful to differentiate MRT from other primary renal neoplasms (15) with rhabdoid differentiation including clear cell, transitional cell, papillary, chromophobe, and collecting duct carcinomas (16-18).
The common genetic basis for rhabdoid tumours is a deletion and/or mutation of the INI1 gene on chromosome 22 (22q11), inactivating the tumour suppressor gene SMARCB1, though these tumours can lack this mutation as seen in this case.
Renal medullary carcinoma: rhabdoid features and the absence of INI1 expression as markers of aggressive behavior.
Immunohistochemical analysis of INI1 protein in malignant pediatric CNS tumors: lack of INI1 in atypical teratoid/ rhabdoid tumors and in a fraction of primitive neuroectodermal tumors without rhabdoid phenotype.
58-61) Deletion and/or mutation of both copies of the SMARCB gene results in loss of INI1 protein expression demonstrable with an anti-INI1 antibody and immunohistochemistry.
Broadening Program into INI1-Deficient Tumors in 2014: Epizyme plans to initiate clinical trials in patients with tumors in which there is genetically altered INI1 after completion of the ongoing Phase 1 study.
Finally, the primary rhabdoid tumor of nerve was composed of rhabdoid cells (Figure 3, C) and showed polyphenotypic immunostaining for cytokeratin, vimentin, epithelial membrane antigen, smooth muscle actin, and neuron-specific enolase; negative staining for myogenin, GFAP, and S100 protein; and loss of INI1 protein expression.
In a recent immunohistochemical study, 5 renal medullary carcinomas exhibited loss of expression of the INI1 (Snf5/Baf47/SmarcB1) protein from tumor cells (Figure 4, B), in contrast to what was observed in high-grade RCC and urothelial carcinoma of the renal pelvis, including those with rhabdoid features, which retained strong INI1 immunoreactivity.
Mutations of the INI1 rhabdoid tumor suppressor gene in medulloblastomas and primitive neuroectodermal tumors of the central nervous system.
2 thyretin GFAP EMA INI1 CPC + +/- +/- - + Papillary ependymoma - NA + +/- + Papillary meningioma NA NA NA + NA Atypical teratoid/ rhabdoid tumor +/- NA + + - Stannio- Kir 7.
2) Other renal tumors of childhood have been associated with recurring genetic abnormalities: deletion or mutations of WT1 and p53 in some Wilms tumors, t (12;15) creating the ETV6-NTRK3 fusion gene in congenital mesoblastic nephroma, and INI1 deletions or mutations in malignant rhabdoid tumors.
Deletion or mutation of INI1, the genetic signature of RT and AT/RT, is reflected by loss of the gene's protein product and the attendant loss of immunoreactivity.