Bcl-6

Bcl-6

A protein that marks germinal center-cell differentiation and regulates lymphocyte differentiation and immune response. Bcl-6 gene rearrangements and Bcl-6 protein expression are frequent in nodular lymphocyte-predominant Hodgkin lymphoma and suggest a germinal center-derived B-cell origin for Barrett esophagitis.
See also: Barrett epithelium, Barrett syndrome.

Bcl-6

A 79-kDa POZ/zinc finger transcriptional repressor and proto-oncogene that maps to chromosome 3q27, which plays a role in B cell activation and proliferation within the germinal centre, and thus is a marker for germinal centre cells and germinal centre lymphomas, especially those lacking gene rearrangements.

Normal expression
Bcl-6 represses lymphocyte activation genes, including blimp-1, which plays a role in plasma cell differentiation. Bcl-6 may thus trigger malignant transformation by inhibiting terminal plasma cell differentiation.

Abnormal expression
Bcl-6 overexpression delays progression through the S phase of the cell cycle/apoptosis, and is present in one third of diffuse large B cell lymphomas
References in periodicals archive ?
Of note, the most widely used immunohistochemistry method is the Hans algorithm, which is based on a few markers, that is, 2 GCB markers, CD10 and BCL-6, and 1 activation marker, MUM1.[sup][17]
Led by first authors Huimin Geng, PhD, assistant professor of laboratory medicine at UCSF, postdoctoral fellow Christian Hurtz, PhD, also of UCSF, and Kyle Lenz, research assistant at OHSU, the group found that cells that exhibit B-cell antigen receptor signaling also express very high levels of a protein known as BCL-6. Then, using BCL-6 as a biomarker, the team used several methods to inhibit B-cell antigen receptor signaling, including treating cells with targeted compounds used in human lymphoma.
Also, restoration of miR-127 significantly inhibits growth, induces apoptosis, and reduces migration and invasion of BC cells by targeting pro-oncogene (BCL-6).
This follicular homing process is directed by Bcl-6, which coordinates the downregulation of T cell zone homing C-C chemokine receptor type 7 (CCR7) in parallel with the upregulation of B cell region homing C-X-C chemokine receptor 5 (CXCR5) [8-12].
The latter response may be via its association with the transcriptional repressor BCL-6, which is released upon activation of PPAR[beta]/[delta] [15].
(3) Further work led to the confirmation that the expression of immunohistochemical markers of cell differentiation (CD10, Bcl-6 and MUM1) can be used to determine the GC and non-GC subtypes of DLBCL, and predict survival similar to the cDNA microarray.
A partir de los hallazgos en expresion diferencial de mRNA de varios marcadores se ha comprobado que los LDDCG se pueden clasificar en dos grupos de pronostico: los de centro germinal y los que no corresponden a centro germinal con base en la deteccion por immunohistoquimica de CD10, bcl-6 y MUM1 (6).
Coexpression of CD10 and BCL-6 has been used as a marker of presumptive germinal center origin and has also been suggested to have prognostic implications, but this remains controversial.
During the study, researchers identified a molecule called heat shock protein 90 (Hsp90) that play a vital role in functioning of a protein called BCL-6, known to drive the activity of lymphoma tumour cells.
While there is tumor individuality, the neoplastic cells usually show a B cell phenotype (CD19, CD20, CD22, CD79a) with coexpression of CD10 and CD43; they also express bcl-2 and bcl-6 and demonstrate light-chain (kappa or lambda) restriction.
bcl-6 gene rearrangement appears to play a role in the pathogenesis of FL, and like with diffuse large B-cell lymphoma, it may correlate with a favorable prognosis.