Similar chemokine receptor profiles in lymphomas with central nervous system involvement - possible biomarkers for patient selection for central nervous system prophylaxis, a retrospective study.

Central nervous system (CNS) relapse occurs in around 5% of diffuse large B-cell lymphoma (DLBCL) cases. No biomarkers to identify high-risk patients have been discovered. We evaluated the expression of lymphocyte-guiding chemokine receptors in systemic and CNS lymphomas. Immunohistochemical staining for CXCR4, CXCR5, CCR7, CXCL12, and CXCL13 was performed on 89 tissue samples, including cases of primary central nervous system lymphoma (PCNSL), secondary CNS lymphoma (sCNSL), and systemic DLBCL. Also, 10 reactive lymph node samples were included. Immunoelectron microscopy was performed on two PCNSLs, one sCNSL, one systemic DLBCL, and one reactive lymph node samples, and staining was performed for CXCR4, CXCR5, CXCL12, and CXCL13. Chi-square test was used to determine correlations between clinical parameters, diagnostic groups, and chemokine receptor expression. Strong nuclear CXCR4 positivity correlated with systemic DLBCL, whereas strong cytoplasmic CXCR5 positivity correlated with CNS involvement (P = 0.003 and P = 0.039). Immunoelectron microscopy revealed a nuclear CXCR4 staining in reactive lymph node, compared with cytoplasmic and membranous localization seen in CNS lymphomas. We found that CNS lymphoma presented a chemokine receptor profile different from systemic disease. Our findings give new information on the CNS tropism of DLBCL and, if confirmed, may contribute to more effective targeting of CNS prophylaxis among patients with DLBCL.

Biological roles and prognostic values of the epithelial-mesenchymal transition-mediating transcription factors Twist, ZEB1 and Slug in diffuse large B-cell lymphoma.

AIMS: To evaluate the biological roles and prognostic significance of the epithelial-mesenchymal transition (EMT)-mediating transcription factors (TFs) Twist, ZEB1 and Slug in patients with diffuse large B-cell lymphoma (DLBCL). EMT has been shown to enhance solid tumour metastasis, invasion, and proliferation. METHODS AND RESULTS: Expression of Twist, ZEB1 and Slug was evaluated immunohistochemically in eight samples from reactive lymphoid tissues and in diagnostic samples from 102 DLBCL patients treated with curative intent with R-CHOP-type chemotherapy. ZEB1 and Slug expression correlated with adverse disease presentation. However, cytoplasmic Slug expression was linked to a favourable disease outcome, whereas nuclear expression of ZEB1 indicated an adverse outcome. CONCLUSIONS: This study shows that an EMT-like process occurs in lymphomas. Of the TFs investigated, ZEB1 seems to be the main one associated with adverse clinical presentation and clinical outcome. Surprisingly, Slug expression in cytoplasm was linked to a favourable prognosis. Further studies are needed to evaluate whether inhibition of ZEB1 could serve as a therapeutic target.

Cell cycle regulation score predicts relapse-free survival in non-germinal centre diffuse large B-cell lymphoma patients treated by means of immunochemotherapy.

OBJECTIVES: The cell cycle is under strict regulation by the retinoblastoma, p53 and p27 pathways, and the disruption of these pathways is an important characteristic of diffuse large B-cell lymphoma (DLBCL). In this study, we wanted to assess the function and prognostic significance of these pathways in DLBCL patients. METHODS: Tissue samples from 120 DLBCL patients treated by means of R-CHOP-type chemotherapy were stained for the cell cycle-regulating proteins p16, p21, p27 and p53, and the germinal centre (GC) phenotype was determined according to Hans' algorithm. Based on the number of impaired cell cycle-regulating pathways a predictive score was obtained, covering three different prognostic groups: a 'favourable' group with damage in 0-1 of the studied pathways, a 'poor' group with damage in all three pathways and an 'intermediate' group comprising the rest of the patients. RESULTS: The prognosis of non-GC DLBCL patients was significantly poorer vs. GC phenotype patients (P = 0.015). The prognostic score proved especially useful among non-GC phenotype patients, with 3-yrs relapse-free survival of 100% vs. 62.6% vs. 24.3% in the 'favourable-', 'intermediate-' and 'poor prognosis' groups, respectively (P = 0.003). CONCLUSION: The prognosis of non-GC DLBCL patients is progressively impaired with the accumulation of damage in different cell cycle-regulating pathways.

Expression and prognostic evaluation of oxidative stress markers in an immunohistochemical study of B-cell derived lymphomas.

Although oxidative stress plays an important role in the biology of solid malignant tumors, little is known about oxidative stress in hematological malignancies. In this study, we evaluated the immunohistochemical expression and clinical correlations of oxidative stress markers and several essential antioxidant enzymes in B-cell lymphomas. Paraffin-embedded diagnostic tissue samples from 18 diffuse large B-cell lymphomas (DLBCL), 18 follicular lymphomas (FL), 19 Hodgkin lymphomas (HL), 7 chronic lymphocytic leukemias (CLL), 7 mantle cell lymphomas (MCL) and 7 mucosa-associated lymphoid tissue (MALT) lymphomas, together with samples from 6 reactive lymph nodes were stained for oxidative stress markers 8-hydroxydeoxyguanosine (8-OHdG) and nitrotyrosine and antioxidant enzymes manganese superoxide dismutase (MnSOD), thioredoxin (Trx) and γ-glutamyl cysteine synthetase (γ-GCS). There was increased 8-OHdG reactivity in DLBCL compared to more indolent lymphomas and reactive lymph nodes. Positivity for Trx was most intense in HL. In DLBCL, positivity for 8-OHdG and nitrotyrosine associated with shorter survival (p = 0.032 and p = 0.026, respectively). This study showed increasing expression of oxidative stress markers and antioxidant enzymes in a series of lymph node samples evolving from reactive lymph nodes to indolent and aggressive lymphomas. These markers seem to have strong prognostic value, but this has to be verified in larger studies.

Oxidative stress and redox state-regulating enzymes have prognostic relevance in diffuse large B-cell lymphoma.

BACKGROUND: Oxidative stress and redox-regulating enzymes may have roles both in lymphomagenesis and resistance to lymphoma therapy. Previous studies from the pre-rituximab era suggest that antioxidant enzyme expression is related to prognosis in diffuse large B-cell lymphoma (DLBCL), although these results cannot be extrapolated to patient populations undergoing modern treatment modalities. In this study we assessed expression of the oxidative stress markers 8-hydroxydeoxyguanosine (8-OHdG) and nitrotyrosine and the antioxidant enzymes thioredoxin (Trx), manganese superoxide dismutase (MnSOD) and glutamate-cysteine ligase (GCL) via immunohistochemistry in 106 patients with DLBCL. All patients were treated with CHOP-like therapy combined with rituximab. Immunostaining results were correlated with progression-free survival, disease-specific survival and traditional prognostic factors of DLBCL. RESULTS: Strong 8-OHdG immunostaining intensity was associated with extranodal involvement (p = 0.00002), a high International Prognostic Index (p = 0.002) and strong Trx (p = 0.011) and GCL (p = 0.0003) expression. Strong Trx staining intensity was associated with poor progression-free survival (p = 0.046) and poor disease-specific survival (p = 0.015). Strong GCL immunostaining intensity predicted poor progression-free survival (p = 0.049). Patients with either strong Trx or strong nitrotyrosine expression showed significantly poorer progression-free survival (p = 0.003) and disease-specific survival (p = 0.031) compared with the other patients. CONCLUSIONS: The redox state-regulating enzymes GCL and Trx are promising markers in the evaluation of DLBCL prognosis in the era of modern immunochemotherapy.

Lack of prognostic value of MMP-9 expression and immunohistochemically defined germinal center phenotype in patients with diffuse large B-cell lymphoma treated with modern chemotherapy with or without CD20 antibody.

Diffuse large B-cell lymphomas (DLBCLs) are a heterogeneous group of lymphomas, with no accepted biological prognostic markers in routine clinical practice. Previously, matrix metalloproteinase (MMP-9), tissue inhibitors of matrix metalloproteinase (TIMP)- 1 and non-germinal center (GC) phenotype have been shown to associate with poor prognosis in DLBCL patients. The aim of this study was to find out whether tissue expression of gelatinases (MMP-2 and MMP-9) or their tissue inhibitors (TIMP-1 and TIMP-2) or immunohistochemically defined GC phenotype could act as prognostic markers in patients treated with modern treatments. Additionally, correlations between these proteins and GC phenotype were investigated. GC phenotype and tissue expression of MMP-2, MMP-9, TIMP-1 and TIMP-2 were analyzed by immunohistochemistry in tissue samples from 114 DLBCL patients. In this study, in patients treated with modern lymphoma treatments (5-year cause-specific survival 69.8%) MMP-2, MMP-9, TIMP-1 or TIMP-2 expression or GC phenotype did not correlate with survival. International Prognostic Index (IPI) and stage were the only factors, which retained their prognostic significance in this patient material. Gelatinases or TIMPs did not correlate with GC phenotype, either. Prognostic markers are dependent on the lymphoma treatments used. In DLBCL patients treated with modern chemotherapy with or without rituximab, MMP-9, TIMP-1 and GC phenotype seem to have lost their prognostic value.