c-Maf

c-Maf is the cellular homologue of the avian retroviral transforming gene v-Maf. c-Maf is a member of the basic leucine zipper family and the AP1 superfamily. Mice engineered to over-express c-Maf in B-cells develop multiple myeloma, those over-expressing c-Maf in T-cells develop T-cell lymphomas.

5%-10% of patient with multiple myeloma have a t(14;16)(q32;q23) translocation fusing the c-Maf gene to the immunoglobulin heavy chain gene. Other cases of myeloma appear to activate c-Maf by other mechanisms, with over-expression in 50% of all myelomas.

Immunohistochemical expression

Staining is nuclear.

 

Normal lymph nodes

some centroblasts within germinal centres positive

 
 

Angioimmunoblastic T-cell lymphoma

23/31 1

 

Adult T-cell lymphoma/leukaemia

3/111

Multiple myeloma

7/81

Peripheral T-cell lymphoma

4191

Mycosis fungoides

011

Anaplastic large cell lymphoma

0111

Extranodal NK/T-cell lymphoma, nasal type

0101

   

Diagnostic utility

References

1 Murakami YI, Yatabe Y, Sakaguchi T, et al. c-Maf expression in angioimmunoblastic T-cell lymphoma. Am J Surg Pathol 2007; 31:1695-702

 

This page last revised 31.12.2007.

©SMUHT/PW Bishop