Intended Use
For In Vitro Diagnostic Use
Summary and Explanation
BCOR is located on chromosome X, in the Xp11.4 locus, and derives its name from its function as an
interacting corepressor of BCL-6 that enhances BCL-6-mediated transcriptional
repression. BCOR is a gene that encodes for an epigenetic regulator
involved in the specification of cell differentiation and body structure
development. Various BCOR aberrations,
represent driver elements of various sarcomas such as Clear Cell Sarcoma of the
Kidney, Primitive Mesenchymal Myxoid Tumor of infancy, small round blue cell
sarcoma, endometrial stromal sarcoma and histologically heterogeneous CNS
neoplasms group with similar genomic methylation patterns known as
CNS-HGNET-BCOR. Furthermore, other BCOR alterations (often loss of function mutations) recur in a
large variety of Mesenchymal, Epithelial, Neural and Hematological Tumors,
suggesting a central role in cancer evolution.
Using next-generation sequencing, an increasing number of
novel gene fusions and other abnormalities have emerged recently in the
spectrum of EWSR1-negative Small Blue Round Cell Tumors (SBRCTs). A subset of
SBRCTs harboring either BCOR gene fusions (BCOR-CCNB3, BCOR-MAML3), BCOR
internal tandem duplications (ITD), or YWHAENUTM2B share a transcriptional
signature including high BCOR mRNA expression, as well as similar histologic
features. Furthermore, other tumors such as Clear Cell Sarcoma of Kidney (CCSK)
and Primitive Myxoid Mesenchymal Tumor of Infancy (PMMTI) also demonstrate BCOR
ITDs and high BCOR gene expression. Recent studies have found the IHC of
BCOR to be a highly sensitive marker for SBRCTs and CCSKs with BCOR
abnormalities and YWHAE rearrangements and can be used as a useful diagnostic
marker in these various molecular subsets.
In another study, Strong diffuse nuclear BCOR staining
(defined as >95% of tumor cells) was seen in the round cell component of 20
(100%) classic YWHAE-NUTM2 high-grade Endometrial Stromal Sarcomas
and the 3 unusual high-grade Endometrial Stromal Sarcomas. It was concluded
that BCOR immunohistochemical staining is a highly sensitive marker for YWHAE-NUTM2 high-grade
Endometrial Stromal Sarcomas with both classic and unusual morphology and
identifies a subset of high-grade Endometrial Stromal Sarcomas
with BCOR alterations, including BCOR rearrangement and
internal tandem duplication.
Presentation
Anti-BCOR
is a mouse monoclonal antibody derived from cell culture supernatant that is
concentrated, dialyzed, filter sterilized and diluted in buffer pH 7.5,
containing BSA and sodium azide as a preservative.
