[Analysis of bcl-6 protein expression and gene rearrangement in diffuse large B-cell lymphoma].

Abstract

OBJECTIVE:

To investigate bcl-6 protein expression and gene rearrangement patterns in diffuse large B-cell lymphoma (DLBCL) and their clinicopathologic significance.

METHODS:

Immunohistochemical studies for bcl-6 and CD10 proteins were performed on 51 cases of DLBCL paraffin-embedded tissues (including 22 nodal samples and 29 extranodal samples) and 10 cases of reactive lymphoid hyperplasia (RLH) paraffin-embedded tissues. Interphase fluorescence in-situ hybridization (FISH) with dual color breakapart probe was also used to identify rearrangement of bcl-6 gene in 32 cases of nodal DLBCL tissues (including 22 paraffin-embedded samples and 10 fresh samples) and 5 cases of RLH paraffin-embedded tissues.

RESULTS:

(1) The rates of bcl-6 protein expression in nodal DLBCL, extranodal DLBCL and RLH were 72.7% (16/22), 75.9% (22/29) and 100.0% (10/10) respectively. The rates of CD10 expression were 40.9% (9/22), 41.4% (12/29) and 100.0% (10/10) respectively. All lymphoma samples which expressed CD10 also showed co-expression of bcl-6 protein. (2) The co-expression of bcl-6 and CD10 was observed in 40.9% (9/22) nodal DLBCL and 41.4% (12/29) extranodal DLBCL. Low clinical stage (stage I and II) was more frequently observed in cases with co-expression of bcl-6 and CD10 (P < 0.05). (3) The rates of bcl-6 gene rearrangement in nodal DLBCL was 28.1% (9/32), with 27.3% (6/22) in paraffin-embedded tissues and 30.0% (3/10) in fresh tissues. There was no statistically significant difference found between the two groups (P > 0.05). Bcl-6 gene rearrangement was not found in all the 5 cases of RLH, and there was a significant difference between RLH and DLBCL (P < 0.05).

CONCLUSIONS:

The rate of bcl-6 protein expression is high in DLBCL cases, and the detection of bcl-6 and CD10 protein co-expression may help in the diagnosis and differential diagnosis of DLBCL. Those DLBCL cases with co-expression of bcl-6 and CD10 may also have a better prognostic implication. On the other hand, bcl-6 gene rearrangement can be identified by interphase FISH with dual color breakapart probe in both paraffin-embedded and fresh lymphoma tissues.

• Authors: Da-liu Min, Hai-long Xia, Xiao-yan Zhou, Meng-hong Sun, Wen-tao Yang, Tai-ming Zhang, Ai-hua Zheng, Da-ren Shi
• Journal: Zhonghua bing li xue za zhi = Chinese journal of pathology (Zhonghua Bing Li Xue Za Zhi) Vol. 34 Issue 6 Pg. 327-31 (Jun 2005) ISSN: 0529-5807 [Print] China
• PMID: 16185497 (Publication Type: English Abstract, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Proto-Oncogene Proteins c-bcl-6
• Neprilysin

Topics

• Diagnosis, Differential
• Female
• Gene Rearrangement
• Humans
• In Situ Hybridization, Fluorescence
• Lymphoma, B-Cell (genetics, metabolism, pathology)
• Lymphoma, Large B-Cell, Diffuse (genetics, metabolism, pathology)
• Male
• Middle Aged
• Neoplasm Staging
• Neprilysin (metabolism)
• Proto-Oncogene Proteins c-bcl-6 (genetics, metabolism)
• Pseudolymphoma (genetics)