High PTX3 expression is associated with a poor prognosis in diffuse large B-cell lymphoma

Tumor-associated macrophages (TAMs) are associated with a poor prognosis of diffuse large B-cell lymphoma (DLBCL). As macrophages are heterogeneous, the immune polarization and their pathological role warrant further study. We characterized the microenvironment of DLBCL by immunohistochemistry in a training set of 132 cases, which included 10 Epstein–Barr virus-encoded small RNA (EBER)-positive and five high-grade B-cell lymphomas, with gene expression profiling in a representative subset of 37 cases. Diffuse large B-cell lymphoma had a differential infiltration of TAMs. The high infiltration of CD68 (pan-macrophages), CD16 (M1-like), CD163, pentraxin 3 (PTX3), and interleukin (IL)-10-positive macrophages (M2c-like) and low infiltration of FOXP3-positive regulatory T lymphocytes (Tregs) correlated with poor survival. Activated B cell-like DLBCL was associated with high CD16, CD163, PTX3, and IL-10, and EBER-positive DLBCL with high CD163 and PTX3. Programmed cell death-ligand 1 positively correlated with CD16, CD163, IL-10, and RGS1. In a multivariate analysis of overall survival, PTX3 and International Prognostic Index were identified as the most relevant variables. The gene expression analysis showed upregulation of genes involved in innate and adaptive immune responses and macrophage and Toll-like receptor pathways in high PTX3 cases. The prognostic relevance of PTX3 was confirmed in a validation set of 159 cases. Finally, in a series from Europe and North America (GSE10846, R-CHOP-like treatment, n = 233) high gene expression of PTX3 correlated with poor survival, and moderately with CSF1R, CD16, MITF, CD163, MYC, and RGS1. Therefore, the high infiltration of M2c-like immune regulatory macrophages and low infiltration of FOXP3-positive Tregs is associated with a poor prognosis in DLBCL, for which PTX3 is a new prognostic biomarker

Genetic and phenotypic characterisation of HIV-associated aggressive B-cell non-Hodgkin lymphomas, which do not occur specifically in this population: diagnostic and prognostic implications

The frequency of aggressive subtypes of B-cell non-Hodgkin lymphoma (B-NHL), such as high-grade B-cell lymphomas (HGBL) with MYC and BCL2 and/or BCL6 rearrangement (HGBL-DH/TH) or Burkitt-like lymphoma (BL) with 11q aberration, is not well known in the HIV setting. We aimed to characterise HIV-associated aggressive B-NHL according to the 2017 WHO criteria, and to identify genotypic and phenotypic features with prognostic impact. Seventy-five HIV-associated aggressive B-NHL were studied by immunohistochemistry (CD10, BCL2, BCL6, MUM1, MYC, and CD30), EBV-encoded RNAs (EBERs), and fluorescence in situ hybridisation (FISH) to evaluate the status of the MYC, BCL2, and BCL6 genes and chromosome 11q. The 2017 WHO classification criteria and the Hans algorithm, for the cell-of-origin classification of diffuse large B-cell lymphomas (DLBCL), were applied. In DLBCL cases, the frequencies of MYC and BCL6 rearrangements (14.9 and 27.7%, respectively) were similar to those described in HIV-negative patients, but BCL2 rearrangements were infrequent (4.3%). MYC expression was identified in 23.4% of DLBCL cases, and coexpression of MYC and BCL2 in 13.0%, which was associated with a worse prognosis. As for BL cases, the expression of MUM1 (30.4%) conferred a worse prognosis. Finally, the prevalence of HGBL-DH/TH and BL-like with 11q aberration are reported in the HIV setting. The phenotypic and genotypic characteristics of HIV-associated aggressive B-NHL are similar to those of the general population, except for the low frequency of BCL2 rearrangements in DLBCL. MYC and BCL2 coexpression in DLBCL, and MUM-1 expression in BL, have a negative prognostic impact on HIV-infected individuals.Peer reviewe

Definition of MYC genetic heteroclonality in diffuse large B-cell lymphoma with 8q24 rearrangement and its impact on protein expression

MYC rearrangement can be detected in a subgroup of diffuse large B-cell lymphoma characterized by unfavorable prognosis. In contrast to Burkitt lymphoma, the correlation between MYC rearrangement and MYC protein expression in diffuse large B-cell lymphoma is less clear, as approximately one-third of rearranged cases show negative or low expression by immunohistochemistry. To better understand whether specific characteristics of the MYC rearrangement may influence its protein expression, we investigated 43 de novo diffuse large B-cell lymphoma positive for 8q24 rearrangement by FISH, using 14 Burkitt lymphoma for comparison. Different cell populations (clones), breakpoints (classical vs non-classical FISH patterns), partner genes (IGH vs non-IGH) and immunostaining were detected and analyzed using computerized image systems. In a subgroup of diffuse large B-cell lymphoma, we observed different clones within the same tumor distinguishing the founder clone with MYC rearrangement alone from other subclones, carrying MYC rearrangement coupled with loss/extra copies of derivatives/normal alleles. This picture, which we defined MYC genetic heteroclonality, was found in 42% of cases and correlated to negative MYC expression (P=0.026). Non-classical FISH breakpoints were detected in 16% of diffuse large B-cell lymphoma without affecting expression (P=0.040). Non-IGH gene was the preferential partner of rearrangement in those diffuse large B-cell lymphoma showing MYC heteroclonality (P=0.016) and/or non-classical FISH breakpoints (P=0.058). MYC heteroclonality was not observed in Burkitt lymphoma and all cases had positive MYC expression. Non-classical FISH MYC breakpoint and non-IGH partner were found in 29 and 20% of Burkitt lymphoma, respectively. In conclusion, MYC genetic heteroclonality is a frequent event in diffuse large B-cell lymphoma and may have a relevant role in modulating MYC expression.Modern Pathology advance online publication, 29 April 2016; doi:10.1038/modpathol.2016.71

FOXP1 status in splenic marginal zone lymphoma, a fluorescence in situ hybridization and immunohistochemistry approach

Splenic marginal zone lymphoma (SMZL) is a well-recognized entity in which chromosomal aberrations seem to be potential markers in diagnosis, prognosis and disease monitoring. FOXP1 is a transcriptional regulator of B lymphopoiesis that is deregulated in some types of NHL. Translocation t(3;14)(p14;q32) has been described in marginal zone lymphomas but few series have studied FOXP1 involvement in SMZL. We performed cytogenetic, fluorescence in situ hybridization (FISH) and immunohistochemical (IHC) studies in a series of 36 patients in order to study the status of FOXP1 in this entity. According to our results, FOXP1 is not rearranged in SMZL, although we were able to demonstrate gains of FOXP1 gene due to trisomy 3/3p by FISH. FOXP1 protein expression seemed to be not related to any aberration and IHC studies are not conclusive

Distinct roles for PARP-1 and PARP-2 in c-Myc-driven B-cell lymphoma in mice.

Dysregulation of the c-Myc oncogene occurs in a wide variety of hematologic malignancies, and its overexpression has been linked with aggressive tumor progression. Here, we show that poly (ADP-ribose) polymerase 1 (PARP-1) and PARP-2 exert opposing influences on progression of c-Myc-driven B-cell lymphoma. PARP-1 and PARP-2 catalyze the synthesis and transfer of ADP-ribose units onto amino acid residues of acceptor proteins in response to DNA strand breaks, playing a central role in the response to DNA damage. Accordingly, PARP inhibitors have emerged as promising new cancer therapeutics. However, the inhibitors currently available for clinical use are not able to discriminate between individual PARP proteins. We found that genetic deletion of PARP-2 prevents c-Myc-driven B-cell lymphoma, whereas PARP-1 deficiency accelerates lymphomagenesis in the Eμ-Myc mouse model of aggressive B-cell lymphoma. Loss of PARP-2 aggravates replication stress in preleukemic Eμ-Myc B cells, resulting in accumulation of DNA damage and concomitant cell death that restricts the c-Myc-driven expansion of B cells, thereby providing protection against B-cell lymphoma. In contrast, PARP-1 deficiency induces a proinflammatory response and an increase in regulatory T cells, likely contributing to immune escape of B-cell lymphoma, resulting in an acceleration of lymphomagenesis. These findings pinpoint specific functions for PARP-1 and PARP-2 in c-Myc-driven lymphomagenesis with antagonistic consequences that may help inform the design of new PARP-centered therapeutic strategies, with selective PARP-2 inhibition potentially representing a new therapeutic approach for the treatment of c-Myc-driven tumors.The authors thank Raul Gomez-Riera for assistance with microscopic analysis, Mar?a Luisa Toribio for providing the HRSIN-ICN1 plasmid, Jessica Gonzalez for technical assistance, and the Flow CytometryUnit and the Genomics Unit at the Centre for Genomic Regulation for assistance with Aseq at the Barcelona Biomedical Research Park. The J.Y. laboratory is funded by the Spanish Ministerio de Econom?a, Industria y Competitividad (grant SAF2017-83565-R) , Spanish Minis-terio de Ciencia e Innovaci?on (grant PID2020-112526RB-I00) , and Fundaci?on Cient?fica de la Asociaci?on Espan~ola Contra el Ca?ncer (grant PROYEI6018Y?ELA) . Work in the J.E.S. laboratory is supported by a core grant to the Laboratory of Molecular Biology from the Med-ical Research Council U105178808) . The F.D. laboratory is supported by a Laboratory of Excellence grant (ANR-10-LABX-0034_Medalis) to Strasbourg University, Centre National de la Recherche Scientifique. The P.N. laboratory is supported by grants from the Spanish Ministry of Economy and Competitiveness/Instituto de Salud Carlos III-Fondo Europeo de Desarrollo Regional (FEDER; PI17/00199 and PI20/00625) and the Generalitat de Catalunya (2017-SGR-225) . The P.M. labora-tory acknowledges support from Centres de Recerca de Catalunya/Generalitat de Catalunya and Fundaci?o Josep Carreras-Obra Social la Caixa for core support, the Spanish Ministry of Economy and Com-petitiveness (grant SAF-2019-108160-R) , the Fundaci?on Uno entre Cienmil, the Obra Social La Caixa (grant LCF/PR/HR19/52160011) , and the German Josep Carreras Leukamie Stiftung. Work at the G.R. and P.M. laboratories are cofinanced by the European Regional Development Fund through the Interreg V-A Spain-France-Andorra Program (project PROTEOblood; grant EFA360/19) . The O.F.-C. labo-ratory is funded by grants from the Spanish Ministry of Science, Inno-vation and Universities (RTI2018-102204-B-I00; cofinanced with European FEDER funds) and the European Research Council (ERC-617840) . T.V.-H. was supported by a Marie Sklodowska Curie fellow-ship (GA792923) . The A.B. laboratory is supported by the Spanish Ministry of Economy and Competitiveness (grant PID2019-104695RB-I00) .S

FOXP1 molecular cytogenetics and protein expression analyses in primary cutaneous large B cell lymphoma, leg-type

FOXP1 protein is expressed in normal activated B cells and overexpressed in a subset of diffuse large B-cell lymphomas, including primary cutaneous large B-cell lymphomas (PCLBCL), leg type. High expression of FOXP1 has been associated to an unfavourable prognosis with independent survival significance. However, little is known regarding the mechanisms underlying the overexpression of FOXP1 in PCLBCL, leg type. Our aims were to analyze FOXP1 cytogenetic status and protein expression in a series of PCLBCL, leg type. Finally, we compared the observed results with those obtained in a group of patients with primary cutaneous follicle centre lymphoma (PCFCL). Fifteen patients with PCLBCL, leg type and nine patients with primary cutaneous follicle centre lymphoma (PCFCL) were included in the study. For each biopsy specimen, FOXP1 translocation and copy number changes were evaluated by fluorescence in situ hybridization (FISH) and protein expression by immunohistochemistry (IHC). Immunohistochemistry showed FOXP1 staining in 13 PCLBCL, leg type, whereas all PCFCL were negative. FISH analysis disclosed no translocations involving FOXP1 gene in any of the cases. However, FOXP1 gene gains (3 to 4 copies) were observed in 82% of samples of PCLBCL, leg type and in 37% of PCFCL. FOXP1 expression was independent from FOXP1 translocation. Our results confirm that overexpression of FOXP1 is present in a considerable proportion of PCLBCL, leg type and might indicate an unfavourable prognosis. Mechanisms not related to translocation seem to be responsible for this overexpression