BOB.1 (B-cell Oct-binding protein 1) is a nuclear marker whose expression is primarily restricted to B-cells (germinal center, mantle zone, and plasma cells). Cases of Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL) typically expressed both OCT2 and BOB.1. The vast majority of cases of Classical Hodgkin Lymphoma (CHL) will be negative for both markers, and a small minority (~20%) will express with one of the two markers. BOB.1 has also been found helpful to differentiate between Mediastinal Large B-Cell Lymphoma and CHL.
In a limited number of studies, a higher expression rate of BOB.1 has been noted in CHL. This finding may be related to the clone (e.g. polyclonal antibody). It is always important to understand the local laboratory performance and clone in use compared to the medical literature. A panel of IHC stains is also important when differentiating cases of Hodgkin lymphoma.
OCT-2 and BOB.1 expression in lymphomas (Browne et al, consolidated published data)
|
Diagnosis
|
BOB.1
|
|
|
21/105 (20%)
|
25/74 (34%)
|
|
|
55/55 (100%)
|
40/40 (100%)
|
|
|
64/68 (94%)
|
47/47 (100%)
|
|
|
2/13 (15%)
|
10/13 (77%)
|
Photomicrographs
References
Browne P, Petrosyan K, Hernandez A, Chan JA. The B-cell transcription factors BSAP, Oct-2, and BOB.1 and the pan-B-cell markers CD20, CD22, and CD79a are useful in the differential diagnosis of classic Hodgkin lymphoma. Am J Clin Pathol. 2003;120: 767–777. doi:10.1309/YCH8-DWUF-FQBK-GPVB
Stein H, Marafioti T, Foss HD, Laumen H, Hummel M, Anagnostopoulos I, et al. Down-regulation of BOB.1/OBF.1 and Oct2 in classical Hodgkin disease but not in lymphocyte predominant Hodgkin disease correlates with immunoglobulin transcription. Blood. 2001;97: 496–501.
McCune RC, Syrbu SI, Vasef MA. Expression profiling of transcription factors Pax-5, Oct-1, Oct-2, BOB.1, and PU.1 in Hodgkin“s and non-Hodgkin”s lymphomas: a comparative study using high throughput tissue microarrays. Mod Pathol. 2006;19: 1010–1018. doi:10.1038/modpathol.3800622
Herbeck R, Teodorescu Brînzeu D, Giubelan M, Lazăr E, Dema A, Ioniţă H. B-cell transcription factors Pax-5, Oct-2, BOB.1, Bcl-6, and MUM1 are useful markers for the diagnosis of nodular lymphocyte predominant Hodgkin lymphoma. Rom J Morphol Embryol. 2011;52: 69–74.
Abd El All HS. Bob-1 is expressed in classic Hodgkin lymphoma. Diagnostic pathology. 2007;2: 10. doi:10.1186/1746-1596-2-10