Clinical significance of nuclear factor and chemokine receptor CXCR4 expression in patients with diffuse large B-cell lymphoma who received rituximab-based therapy

Background/Aims: This study investigated the expression of nuclear factor ${\kappa}B$ (NF-${\kappa}B$) and the chemokine receptor (CXCR4) in patients with diffuse large B-cell lymphoma (DLBCL) who received rituximab-based therapy. Methods: Seventy patients with DLBCL and treated with rituximab-CHOP (R-CHOP) were included, and immunohistochemistry was performed to determine the expression of NF-${\kappa}B$ ($I{\kappa}B$ kinase ${\alpha}$, p50, and p100/p52) and CXCR4. To classify DLBCL cases as germinal center B-cell-like (GCB) and non-GCB, additional immunohistochemical expression of CD10, bcl-6, or MUM1 was used in this study. The expression was divided into two groups according to the intensity score (negative, 0 or 1+; positive, 2+ or 3+). Results: The median age of the patients was 66 years (range, 17 to 87), and 58.6% were male. Twenty-seven patients (38.6%) had stage III or IV disease at diagnosis. Twenty-three patients (32.9%) were categorized as high or high-intermediate risk according to their International Prognostic Indexs (IPIs). The overall incidence of bone marrow involvement was 5.7%. Rates of positive NF-${\kappa}B$ and CXCR4 expression were 84.2% and 88.6%, respectively. High NF-${\kappa}B$ expression was associated with CXCR4 expression (p = 0.002), and 56 patients (80.0%) showed coexpression. However, the expression of NF-${\kappa}B$ or CXCR4 was not associated with overall survival and EFS. On multivariate analysis that included age, gender, performance status, stage, and the IPI, no significant association between the grade of NF-${\kappa}B$ or CXCR4 expression and survival was observed. Conclusions: The current study suggests that the tissue expression of NF-${\kappa}B$ and CXCR4 may not be an independent prognostic marker in DLBCL patients treated with R-CHOP.