SMARCB1

Tumour Suppressor
SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily B member 1 UniProt accession Q12824

Core component of the BAF (hSWI/SNF) complex. This ATP-dependent chromatin-remodeling complex plays important roles in cell proliferation and differentiation, in cellular antiviral activities and inhibition of tumor formation. The BAF complex is able to create a stable, altered form of chromatin that constrains fewer negative supercoils than normal.

This change in supercoiling would be due to the conversion of up to one-half of the nucleosomes on polynucleosomal arrays into asymmetric structures, termed altosomes, each composed of 2 histones octamers. Stimulates in vitro the remodeling activity of SMARCA4/BRG1/BAF190A. Involved in activation of CSF1 promoter.

Belongs to the neural progenitors-specific chromatin remodeling complex (npBAF complex) and the neuron-specific chromatin remodeling complex (nBAF complex). During neural development a switch from a stem/progenitor to a postmitotic chromatin remodeling mechanism occurs as neurons exit the cell cycle and become committed to their adult state. The transition from proliferating neural stem/progenitor cells to postmitotic neurons requires a switch in subunit composition of the npBAF and nBAF complexes.

As neural progenitors exit mitosis and differentiate into neurons, npBAF complexes which contain ACTL6A/BAF53A and PHF10/BAF45A, are exchanged for homologous alternative ACTL6B/BAF53B and DPF1/BAF45B or DPF3/BAF45C subunits in neuron-specific complexes (nBAF). The npBAF complex is essential for the self-renewal/proliferative capacity of the multipotent neural stem cells. The nBAF complex along with CREST plays a role regulating the activity of genes essential for dendrite growth (By similarity).

Plays a key role in cell-cycle control and causes cell cycle arrest in G0/G1

Source: UniProt

Component of the multiprotein chromatin-remodeling complexes SWI/SNF: SWI/SNF-A (BAF), SWI/SNF-B (PBAF) and related complexes. The canonical complex contains a catalytic subunit (either SMARCA4/BRG1/BAF190A or SMARCA2/BRM/BAF190B) and at least SMARCE1, ACTL6A/BAF53, SMARCC1/BAF155, SMARCC2/BAF170, and SMARCB1/SNF5/BAF47. Other subunits specific to each of the complexes may also be present permitting several possible combinations developmentally and tissue specific (Probable).

Component of the BAF complex, which includes at least actin (ACTB), ARID1A/BAF250A, ARID1B/BAF250B, SMARCA2/BRM, SMARCA4/BRG1/BAF190A, ACTL6A/BAF53, ACTL6B/BAF53B, SMARCE1/BAF57 SMARCC1/BAF155, SMARCC2/BAF170, SMARCB1/SNF5/INI1, and one or more SMARCD1/BAF60A, SMARCD2/BAF60B, or SMARCD3/BAF60C. In muscle cells, the BAF complex also contains DPF3 (PubMed:18765789, PubMed:8895581). Component of neural progenitors-specific chromatin remodeling complex (npBAF complex) composed of at least, ARID1A/BAF250A or ARID1B/BAF250B, SMARCD1/BAF60A, SMARCD3/BAF60C, SMARCA2/BRM/BAF190B, SMARCA4/BRG1/BAF190A, SMARCB1/BAF47, SMARCC1/BAF155, SMARCE1/BAF57, SMARCC2/BAF170, PHF10/BAF45A, ACTL6A/BAF53A and actin.

Component of neuron-specific chromatin remodeling complex (nBAF complex) composed of at least, ARID1A/BAF250A or ARID1B/BAF250B, SMARCD1/BAF60A, SMARCD3/BAF60C, SMARCA2/BRM/BAF190B, SMARCA4/BRG1/BAF190A, SMARCB1/BAF47, SMARCC1/BAF155, SMARCE1/BAF57, SMARCC2/BAF170, DPF1/BAF45B, DPF3/BAF45C, ACTL6B/BAF53B and actin (By similarity). Component of the SWI/SNF-B (PBAF) chromatin remodeling complex, at least composed of SMARCA4/BRG1, SMARCB1/BAF47/SNF5, ACTL6A/BAF53A or ACTL6B/BAF53B, SMARCE1/BAF57, SMARCD1/BAF60A, SMARCD2/BAF60B, perhaps SMARCD3/BAF60C, SMARCC1/BAF155, SMARCC2/BAF170, PBRM1/BAF180, ARID2/BAF200 and actin (PubMed:26601204). Binds to double-stranded DNA.

Interacts with CEBPB (when not methylated) (PubMed:20111005). Interacts with PIH1D1 (PubMed:22368283). Interacts with MYK and MAEL (PubMed:10319872).

Interacts with PPP1R15A (PubMed:10490642, PubMed:12016208). Interacts with DPF2 (PubMed:20460684). Interacts with YWHAZ (PubMed:16959763).

Interacts with ERCC6 (PubMed:24874740). Interacts with FOS, FOSB isoform 1 and 2, FOSL1 and FOSL2 (By similarity)

(Microbial infection) Binds tightly to the human immunodeficiency virus-type 1 (HIV-1) integrase in vitro and stimulates its DNA-joining activity. Interacts with human papillomavirus 18 E1 protein to stimulate its viral replication (PubMed:10365963). Interacts with Epstein-Barr virus protein EBNA-2 (PubMed:8709224)

Source: UniProt
Nucleus
Source: UniProt

The N-terminal DNA-binding region is structurally similar to winged helix domains

Source: UniProt
  • Rhabdoid tumor predisposition syndrome 1 (RTPS1)

    A familial cancer syndrome predisposing to renal or extrarenal malignant rhabdoid tumors and to a variety of tumors of the central nervous system, including choroid plexus carcinoma, medulloblastoma, and central primitive neuroectodermal tumors. Rhabdoid tumors are the most aggressive and lethal malignancies occurring in early childhood.

  • Schwannomatosis 1 (SWN1)

    An autosomal dominant tumor predisposition syndrome characterized by the development of multiple benign nerve sheath tumors called schwannomas on cranial, spinal, and peripheral nerves, without involvement of the vestibular nerve. Affected individuals may also have multiple meningiomas.

  • Coffin-Siris syndrome 3 (CSS3)

    A form of Coffin-Siris syndrome, a congenital multiple malformation syndrome with broad phenotypic and genetic variability. Cardinal features are intellectual disability, coarse facial features, hypertrichosis, and hypoplastic or absent fifth digit nails or phalanges. Additional features include malformations of the cardiac, gastrointestinal, genitourinary, and/or central nervous systems.

    Sucking/feeding difficulties, poor growth, ophthalmologic abnormalities, hearing impairment, and spinal anomalies are common findings. Both autosomal dominant and autosomal recessive inheritance patterns have been reported.

Source: UniProt

Click a pathway to open the interactive Reactome viewer.

Pathway list and interactive viewer: Reactome

Synthetic Lethal Network

Genes with an experimentally identified or computationally predicted synthetic-lethal relationship to SMARCB1, aggregated across our SSL data sources. Click any partner node to view that gene’s page.

Nodes and edges are coloured by the SSL data source. Partners appearing in more than one source are shown in grey.

BioGRID SLOrth SynLethDB MexDrugs Multi-source
Sources: BioGRID, SLOrth, SynLethDB, MexDrugs

Clinical Trials

Total Trials Found: 1

NCT ID Condition Brief Title Phase Status
NCT05286801 Atypical Teratoid/Rhabdoid Tumor, Epithelioid Sarcoma, Kidney Medullary Carcinoma, Malignant Solid Neoplasm, Poorly Differentiated Chordoma, Recurrent Atypical Teratoid/Rhabdoid Tumor, Recurrent Chordoma, Recurrent Epithelioid Sarcoma, Recurrent Kidney Medullary Carcinoma, Recurrent Malignant Solid Neoplasm, Recurrent Rhabdoid Tumor, Refractory Atypical Teratoid/Rhabdoid Tumor, Refractory Chordoma, Refractory Epithelioid Sarcoma, Refractory Kidney Medullary Carcinoma, Refractory Malignant Solid Neoplasm, Refractory Rhabdoid Tumor, Rhabdoid Tumor Tiragolumab and Atezolizumab for the Treatment of Relapsed or Refractory SMARCB1 or SMARCA4 Deficient Tumors PHASE1, PHASE2 ACTIVE_NOT_RECRUITING
NCT05407441 Atypical Teratoid Rhabdoid Tumor, INI1 (SMARCB1)-Deficient Primary CNS Malignant Tumors, SMARCA4-deficient Primary CNS Malignant Tumors, Malignant Rhabdoid Tumor (MRT), Rhabdoid Tumor of the Kidney (RTK), Epithelioid Sarcoma, Chordoma Tazemetostat+Nivo/Ipi in INI1-Neg/SMARCA4-Def Tumors PHASE1, PHASE2 ACTIVE_NOT_RECRUITING
NCT04868799 ATRT Finding New Targets by Proteomic Approaches (InnovRT1) N/A COMPLETED
NCT03213665 Advanced Malignant Solid Neoplasm, Ann Arbor Stage III Hodgkin Lymphoma, Ann Arbor Stage III Non-Hodgkin Lymphoma, Ann Arbor Stage IV Hodgkin Lymphoma, Ann Arbor Stage IV Non-Hodgkin Lymphoma, Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumor, Low Grade Glioma, Recurrent Ependymoma, Recurrent Ewing Sarcoma, Recurrent Glioma, Recurrent Hepatoblastoma, Recurrent Hodgkin Lymphoma, Recurrent Langerhans Cell Histiocytosis, Recurrent Malignant Germ Cell Tumor, Recurrent Malignant Glioma, Recurrent Malignant Solid Neoplasm, Recurrent Medulloblastoma, Recurrent Neuroblastoma, Recurrent Non-Hodgkin Lymphoma, Recurrent Osteosarcoma, Recurrent Peripheral Primitive Neuroectodermal Tumor, Recurrent Primary Central Nervous System Neoplasm, Recurrent Rhabdoid Tumor, Recurrent Rhabdomyosarcoma, Recurrent Soft Tissue Sarcoma, Refractory Hodgkin Lymphoma, Refractory Langerhans Cell Histiocytosis, Refractory Malignant Germ Cell Tumor, Refractory Malignant Glioma, Refractory Malignant Solid Neoplasm, Refractory Medulloblastoma, Refractory Neuroblastoma, Refractory Non-Hodgkin Lymphoma, Refractory Osteosarcoma, Refractory Peripheral Primitive Neuroectodermal Tumor, Refractory Rhabdoid Tumor, Refractory Soft Tissue Sarcoma, Rhabdoid Tumor, Stage III Soft Tissue Sarcoma AJCC v7, Stage IV Soft Tissue Sarcoma AJCC v7, Wilms Tumor Tazemetostat in Treating Patients With Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphoma, or Histiocytic Disorders With EZH2, SMARCB1, or SMARCA4 Gene Mutations (A Pediatric MATCH Treatment Trial) PHASE2 COMPLETED
NCT07438626 Phase II, Sacituzumab, Tirumotecan, SMARCB1-deficient Renal Medullary Carcinoma Phase II Trial of Sacituzumab Tirumotecan in Patients With SMARCB1-Deficient Renal Medullary Carcinoma PHASE2 NOT_YET_RECRUITING
NCT04965753 Advanced Synovial Sarcoma FHD-609 in Subjects With Advanced Synovial Sarcoma or Advanced SMARCB1-Loss Tumors PHASE1 TERMINATED
NCT03587662 Metastatic Kidney Medullary Carcinoma, Metastatic Renal Cell Carcinoma, SMARCB1 Negative, Stage III Renal Cell Cancer AJCC v8, Stage IV Renal Cell Cancer AJCC v8 Ixazomib, Gemcitabine, and Doxorubicin in Treating Patients With Locally Advanced or Metastatic Kidney Cancer PHASE2 ACTIVE_NOT_RECRUITING
NCT05355753 Synovial Sarcoma, Soft Tissue Sarcoma A Study to Assess the Safety and Tolerability of CFT8634 in Locally Advanced or Metastatic SMARCB1-Perturbed Cancers, Including Synovial Sarcoma and SMARCB1-Null Tumors PHASE1 TERMINATED
NCT06444880 SMARCB1-Deficient Malignancies Phase II Trial of Ubamatamab Alone or in Combination With Cemiplimab in MUC16-Expressing SMARCB1-Deficient Malignancies PHASE2 RECRUITING
NCT05151588 Sinonasal Carcinoma Induction Chemotherapy and Tazemetostat for Locally Advanced SMARCB1-deficient Sinonasal Carcinoma PHASE2 NOT_YET_RECRUITING