Which of the following is positive in Follicular lymphoma?
Follicular lymphoma likely arises from germinal center B cells and is strongly associated with chromosomal translocations involving BCL2. Its hallmark is a (14;18) translocation that juxtaposes the IGH locus on chromosome 14 and the BCL2 locus on chromosome 18. The t(14;18) is seen in up to 90% of follicular lymphomas, and leads to overexpression of BCL2. BCL2 antagonizes apoptosis and promotes the survival of follicular lymphoma cells. Notably, while normal germinal centers contain numerous B cells undergoing apoptosis, follicular lymphoma is characteristically devoid of apoptotic cells. BCL 10 : associated with extra nodal marginal zone lymphoma The t(14;18)(q32;q21) and t(1;14) (p22;q32) translocations cause increased expression of intact MALT1 and BCL-10 protein respectively. This translocation is associated with gastric MALToma. Each of the three translocations has the same net effect, the constitutive activation of NF-kB, a transcription factor that promotes B-cell growth and survival. Antigen dependent activation of NF-kB in normal B and T cells. requires both BCL-10 and MLT, which work together in a pathway downstream of the B- and T-cell antigen receptors. Thus, H. pylori-induced inflammation may trigger NF-kB activation through the MLT/BCL-10 pathway in MALTomas that lack these translocations. Removal of this stimulus may explain why these tumors tend to respond to H. pylori eradication. In contrast, NF-kB is constitutively active in tumors bearing translocations involving MLT or BCL10, and H. pylori treatment is ineffective. BCL 6 : associated with diffuse large b cell lymphoma(DLBCL). DLBCL is most common subtype of non Hodgkin lymphoma globally. BCL 1 : also called cyclin D1 and is associated with Mantle Cell Lymphoma
Bcl 2
Bcl 6
Bcl 1
Bcl 10
NEET 2019