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For CNS lymphomas (CNSL), there is a high need for minimally invasive and easily obtainable diagnostic markers. Intrathecal IgM synthesis can easily be determined in routine CSF diagnostics. The aim of this study was to systematically investigate the diagnostic potential of intrathecal IgM synthesis in primary and secondary CNSL (PCNSL and SCNSL). In this retrospective study, patients with a biopsy‐proven diagnosis of PCNSL or SCNSL were compared with patients with other neurological diseases in whom CNSL was initially the primary radiological differential diagnosis based on MRI. Sensitivity and specificity of intrathecal IgM synthesis were calculated using receiver operating characteristic curves. Seventy patients with CNSL were included (49 PCNSL and 21 SCNSL) and compared to 70 control patients. The sensitivity and specificity for the diagnosis of CNSL were 49% and 87%, respectively, for the entire patient population and 66% and 91% after selection for cases with tumor access to the CSF system and isolated intrathecal IgM synthesis. In cases with MRI‐based radiological suspicion of CNSL, intrathecal IgM synthesis has good specificity but limited sensitivity. Because of its low‐threshold availability, analysis of intrathecal IgM synthesis has the potential to lead to higher diagnostic accuracy, especially in resource‐limited settings, and deserves further study. [ABSTRACT FROM AUTHOR]

Summary: Different studies have characterized the microenvironment and its prognostic impact in classic Hodgkin lymphoma whereas such analyses are pending for nodular lymphocyte‐predominant Hodgkin lymphoma (NLPHL). We thus investigated characteristics of tumour cells and microenvironment in NLPHL and evaluated possible correlations with the clinical presentation. Lymph node samples from 152 NLPHL patients who had first‐line treatment within the randomized German Hodgkin Study Group HD16–HD18 trials were available and analysed with regard to IgD status and nuclear size of the tumour cells as well as presence of PD1‐positive follicular T helper cells and CD163‐positive macrophages in the microenvironment. While large tumour cell nuclei and high numbers of PD1‐positive follicular T helper cells in the microenvironment were more common in patients presenting with early/intermediate stages than in patients with advanced‐stage disease (p < 0.0001, unpaired t‐test; p = 0.0022, Mann–Whitney test), no differences between risk groups were observed in terms of the IgD status of the tumour cells and the content of CD163‐positive macrophages in the microenvironment. PD1‐positive follicular T helper cells were present in both cases with typical and variant growth patterns and rosetting around the tumour cells was observed in 96% of patients, indicating an important role of PD1‐positive follicular T helper cells in NLPHL. [ABSTRACT FROM AUTHOR]

Classic Hodgkin lymphoma (cHL) is usually characterized by a low tumour cell content, derived from crippled germinal centre B cells. Rare cases have been described in which the tumour cells show clonal T-cell receptor rearrangements. From a clinicopathological perspective, it is unclear if these cases should be classified as cHL or anaplastic large T-cell lymphoma (ALCL). Since we recently observed differences in the motility of ALCL and cHL tumour cells, here, we aimed to obtain a better understanding of T-cell-derived cHL by investigating their global proteomic profiles and their motility. In a proteomics analysis, when only motility-associated proteins were regarded, T-cell-derived cHL cell lines showed the highest similarity to ALK-ALCL cell lines. In contrast, T-cell-derived cHL cell lines presented a very low overall motility, similar to that observed in conventional cHL. Whereas all ALCL cell lines, as well as T-cell-derived cHL, predominantly presented an amoeboid migration pattern with uropod at the rear, conventional cHL never presented with uropods. The migration of ALCL cell lines was strongly impaired upon application of different inhibitors. This effect was less pronounced in cHL cell lines and almost invisible in T-cell-derived cHL. In summary, our cell line-derived data suggest that based on proteomics and migration behaviour, T-cell-derived cHL is a neoplasm that shares features with both cHL and ALCL and is not an ALCL with low tumour cell content. Complementary clinical studies on this lymphoma are warranted. [ABSTRACT FROM AUTHOR]

Summary: We retrospectively investigated histopathological growth patterns in individuals with advanced nodular lymphocyte‐predominant Hodgkin lymphoma (NLPHL) treated within the randomized HD18 study. In all, 35/60 patients (58%) presented with atypical growth patterns. Patients with atypical growth patterns more often had stage IV disease (P = 0·0354) and splenic involvement (P = 0·0048) than patients with typical growth patterns; a positive positron emission tomography after two cycles of chemotherapy (PET‐2) tended to be more common (P = 0·1078). Five‐year progression‐free survival [hazard ratio (HR) = 0·86; 95% confidence interval (CI) = 0·49–1·47] and overall survival (HR = 0·85; 95% CI = 0·49–1·51) did not differ between the groups after study treatment with PET‐2‐guided escalated BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone). Thus, advanced NLPHL is often associated with atypical growth patterns but their prognostic impact is compensated by PET‐2‐guided escalated BEACOPP. [ABSTRACT FROM AUTHOR]

Summary: Mutations in SOCS1 are frequent in primary mediastinal B‐cell lymphoma and classical Hodgkin lymphoma. In the latter, SOCS1 mutations affect the length of the encoded protein (major mutations) and are associated with shorter patient survival. Two independent studies examined the prognostic impact of SOCS1 mutations in diffuse large B‐cell lymphoma (DLBCL) and showed differing results. This may be due to the small number of included patients, the heterogeneity of patients' demographics and the distinct treatment schemes in these studies. To overcome the size limitations of these previous studies, we assessed SOCS1 mutations in the RICOVER‐60 cohort. The cohort uniformly consists of elderly patients (aged 61–80 years) treated with the CHOP‐14 scheme (cyclophosphamide, hydroxydaunorubicin, vincristine, prednisolone at 14‐day intervals) with or without an additional rituximab treatment. Patient outcomes were analysed with regard to overall SOCS1 mutation frequency, major and minor mutations and a novel impact‐based classifier – against the treatment modalities. Patients harbouring putative pathogenic SOCS1 mutations showed significant reduced overall survival within the CHOP plus rituximab group. Hence, putative pathogenic SOCS1 mutations seem to efface the beneficial effect of the therapeutic CD20 antibody. Comparing published data of whole exome and transcriptome sequencing of a large DLBCL cohort confirmed that predicted deleterious SOCS1 mutations forecast pre‐eminent survival in early onset DLBCL. [ABSTRACT FROM AUTHOR]

Summary: Mantle cell lymphoma (MCL) is still considered incurable and the course of the disease is highly variable. Established risk factors include the Mantle Cell Lymphoma International Prognostic Index (MIPI) and the quantification of the proliferation rate of the tumour cells, e.g. by Ki‐67 immunohistochemistry. In this study, we aimed to validate the prognostic value of the gene expression‐based MCL35 proliferation assay in patient cohorts from randomized trials of the European Mantle Cell Lymphoma Network. Using this assay, we analysed the gene expression proliferation signature in routine diagnostic lymph node specimens from MCL Younger and MCL Elderly trial patients, and the calculated MCL35 score was used to assign MCL patients to low (61%), standard (27%) or high (12%) risk groups with significantly different outcomes. We confirm here in our prospective clinical trial cohort of MCL patients, that the MCL35 assay is strongly prognostic, providing additional information to the Ki‐67 index and the MIPI. Thus, this robust assay may assist in making treatment decisions or in devising risk‐adapted prospective clinical trials in the future. [ABSTRACT FROM AUTHOR]

Background & Aims: Diverging trends of cholangiocarcinoma (CCA) incidence in different countries warrant further subtype‐specific characterization. In this study, we aimed to determine current epidemiologic trends of CCA in Germany and evaluated impact of misclassification of perihilar CCA (pCCA) as intrahepatic CCA (iCCA). Methods: Subtype‐specific incidence was assessed based on data of approximately 40 million German citizens from 2003 to 2014, and mortality data of entire Germany were assessed from 1998 to 2015. Results: Reclassification of pCCA to extrahepatic CCA (eCCA) led to an enhancement of an increasing average annual percentage change (AAPC) for iCCA in men (3.8 to 4.8) and women (3.3 to 4.8). Likewise, a stable or slightly decreasing trend in extrahepatic CCA was strengthened in women (AAPC: −0.2 to −0.9) and men (1 to 0.5). pCCA accounted for 13% of biliary tract tumours (iCCA: 46%, distal CCA: 41%). In line with incidence trends, mortality of iCCA in Germany increased for women (AAPC 7.8) and men (6.5), while it was stable for eCCA (women: −0.6, men: 2.1). Conclusion: Incidence of iCCA in Germany is increasing while it is stable for eCCA. Misclassification of pCCA as iCCA is present, but clearly declining. See Editorial on Page 260 [ABSTRACT FROM AUTHOR]

Aims To investigate the expression of the programmed cell death 1 ( PD-1) receptor-programmed cell death ligand 1 ( PD-L1) pathway and the clinicopathological characteristics in extrahepatic cholangiocarcinoma ( eCCA). Methods and results Tissue samples from patients with eCCA [ n = 69; perihilar cholangiocarcinoma ( CCA), 40; and distal CCA, 29] who underwent surgical resection in the period from 2007 to 2015 were evaluated for PD-1, PD-L1, CD3 and CD163 expression, and correlations with clinicopathological characteristics, including survival data, were determined. PD-L1 was found on both tumour cells of eCCA (8/69, 11.6%) and tumour-associated macrophages (21/69, 30.4%). Significant correlations of PD-L1 expression on cancer cells with venous invasion ( P = 0.031) and poor differentiation of the tumour ( P = 0.048) were observed. In 19 of 69 (27.5%) samples, tumour-infiltrating lymphocytes ( TILs) expressed PD-1, whereas infiltration with CD3-positive and CD163-positive cells was found in 63 of 69 (91.3%) and 68 of 69 (98.6%) cases, respectively. The presence of fewer than five CD3-positive cells per high-power field was significantly correlated with poorer differentiation ( P = 0.015) and venous invasion ( P < 0.001) of CCA. PD-L1 expression was not correlated with patient survival, but PD-L1 expression on tumour cells combined with low infiltration of CD3-positive TILs was associated with an unfavourable outcome ( P = 0.027). Conclusion Only a small number of eCCA patients are PD-L1-positive, which might be important for future application of PD-1/ PD-L1-targeted immune-modulating therapy in these patients. A small subgroup of eCCAs with PD-L1 expression and low lymphocytic infiltration showed more invasive growth and worse overall survival. [ABSTRACT FROM AUTHOR]

Angioimmunoblastic T-cell lymphomas ( AITLs) frequently carry mutations in the TET2 and IDH2 genes. TET2 mutations represent early genetic lesions as they had already been detected in haematopoietic precursor cells of AITL patients. We show by analysis of whole-tissue sections and microdissected PD1+ cells that the frequency of TET2-mutated AITL is presumably even higher than reported (12/13 cases in our collection; 92%). In two-thirds of informative AITLs (6/9), a fraction of B cells was also TET2-mutated. Investigation of four AITLs by TET2 and IGHV gene sequencing of single microdissected B cells showed that between 10% and 60% of polyclonal B cells in AITL lymph nodes harboured the identical TET2 mutations of the respective T-cell lymphoma clone. Thus, TET2-mutated haematopoietic precursor cells in AITL patients not only give rise to the T-cell lymphoma but also generate a large population of mutated mature B cells. Future studies will show whether this is a reason why AITL patients frequently also develop B-cell lymphomas. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background and aims CD15 is expressed by various cancer types; among these are intrahepatic and perihilar cholangiocarcinoma ( CCA). The aim of this study was to elucidate CD15 expression in distal CCA as well as in dysplastic biliary tissue and to determine its prognostic significance. Methods and results Tissue samples from patients with intrahepatic ( iCCA, n = 22), perihilar ( pCCA, n = 7) and distal CCA ( dCCA, n = 15), who underwent surgical resection in the period from 2010 to 2015 were evaluated for CD15 expression. Tissue of synchronous lymph node metastasis ( n = 13), CCA-associated dysplasia ( n = 20), dysplasia in intraductal biopsies ( n = 10) and benign proliferations ( n = 12), as well as inflammatory biliary lesions ( n = 28) and non-inflammatory bile ducts ( n = 23), were evaluated equally for CD15 expression. CD15 was found to be expressed highly in iCCA (81.8%), pCCA (85.7%), dCCA (73.3%), CCA-associated dysplasia (70.0%), dysplasia in intraductal biopsies (100%) and metastatic tissue (84.6%). CD15 expression was negative in 58 of 64 benign bile duct alterations resulting in an overall sensitivity and specificity of CD15 in CCA of 80.7 and 90.6% patients, respectively. CD15 expression was correlated significantly with a decreased overall survival in patients with CD15-positive CCA associated dysplasia ( P = 0.003). However, CD15 expression in the invasive tumour component was not correlated with clinical outcome. Conclusion CD15 is a sensitive and specific marker for intraepithelial and invasive neoplasias of the bile duct. Therefore, it can be helpful in the delineation of dysplastic and neoplastic biliary cells from non-neoplastic tissue, which frequently causes a diagnostic problem in indeterminate biliary stricture. [ABSTRACT FROM AUTHOR]

The metabolic properties of lymphomas derived from germinal center (GC) B cells have important implications for therapeutic strategies. In this study, we have compared metabolic features of Hodgkin-Reed-Sternberg (HRS) cells, the tumor cells of classical Hodgkin's lymphoma (cHL), one of the most frequent (post-)GC-derived B-cell lymphomas, with their normal GC B cell counterparts. We found that the ratio of oxidative to nonoxidative energy conversion was clearly shifted toward oxidative phosphorylation (OXPHOS)-linked ATP synthesis in HRS cells as compared to GC B cells. Mitochondrial mass, the expression of numerous key proteins of oxidative metabolism and markers of mitochondrial biogenesis were markedly upregulated in cHL cell lines and in primary cHL cases. NFkappaB promoted this shift to OXPHOS. Functional analysis indicated that both cell growth and viability of HRS cells depended on OXPHOS. The high rates of OXPHOS correlated with an almost complete lack of lactate production in HRS cells not observed in other GC B-cell lymphoma cell lines. Overall, we conclude that OXPHOS dominates energy conversion in HRS cells, while nonoxidative ATP production plays a subordinate role. Our results suggest that OXPHOS could be a new therapeutic target and may provide an avenue toward new treatment strategies in cHL. [ABSTRACT FROM AUTHOR]

Nodular lymphocyte predominant Hodgkin lymphoma ( NLPHL) and T cell/histiocyte rich large B cell lymphoma ( THRLBCL) usually affect middle-aged men, show tumour cells with a B cell phenotype and a low tumour cell content. Whereas the clinical behaviour of NLPHL is indolent, THRLBCL presents with advanced stage disease and an aggressive behaviour. In the present study, array comparative genomic hybridization was performed in seven typical NLPHL, four THRLBCL-like NLPHL variants, six THRLBCL and four diffuse large B cell lymphomas ( DLBCL) derived from NLPHL. The number of genomic aberrations was higher in THRLBCL compared with typical and THRLBCL-like variant of NLPHL. Gains of 2p16.1 and losses of 2p11.2 and 9p11.2 were commonly observed in typical and THRLBCL-like variants of NLPHL as well as THRLBCL. Gains of 2p16.1, affecting the REL locus were confirmed in an independent cohort. Expression of the REL protein was observed at similar frequencies in typical and THRLBCL-like variant of NLPHL as well as THRLBCL (33-38%). In conclusion, the present study reveals further similarities between NLPHL and THRLBCL on the genomic level, confirming that these entities are part of a pathobiological spectrum with common molecular features, but varying clinical presentations. [ABSTRACT FROM AUTHOR]

Nodular lymphocyte-predominant Hodgkin lymphoma ( NLPHL) is a rare lymphoma entity. We performed a matched-pair analysis to evaluate the prognostic impact of several histopathological features in this distinct Hodgkin lymphoma subtype. Lymph node samples of NLPHL patients were tested for CD15, IgD, phosphorylated STAT6, ICOS and Epstein-Barr virus status of the malignant lymphocyte-predominant cells as well as epithelioid cell clusters and activated T cells in the microenvironment. None of these features was associated with a particular clinical outcome. However, patients presenting with epithelioid cell clusters showed a non-significant trend towards a lower relapse rate, justifying further evaluation of this marker. [ABSTRACT FROM AUTHOR]

Composite lymphomas (CL) represent the occurrence of two distinct lymphomas in the same patient. Often, CL share a common cellular origin, thus representing a unique model to investigate the multistep genetic path leading to lymphomagenesis in general and to the specific development of each distinct lymphoma component in particular. Here, we present the molecular analysis of a case consisting of an unusual Hodgkin lymphoma (HL) and a mantle cell lymphoma (MCL), intimately admixed within one another in lymph nodes and bone marrow yet phenotypically distinct, in a patient who first presented with splenic/leukemic MCL two years earlier. MCL and Hodgkin and Reed/Sternberg (HRS) cells harbored identical immunoglobulin (Ig) VH gene rearrangements with shared somatic mutations, proving their common clonal origin from a (post-)germinal center (GC) B cell. This also demonstrates the (post-)GC origin of MCL with mutated IgV genes. Both lymphomas carried the same CCND1/IGH translocation and, unexpectedly for HL, expressed cyclin D1 and OCT2. Thus, HRS cells are able to preserve IGH locus activity (otherwise usually silenced in HL) to promote expression of an oncogene translocated into this locus. Both lymphoma populations further showed an identical TP53 function-impairing mutation, and later acquired a TP53 heterozygous deletion independently from one another (convergent evolution). The surprisingly close genetic relationship of the lymphomas, together with their histological intermingling and the clinical history of the patient, suggests subclonal evolution of HL from MCL as a plausible pathway in alternative to that so far described in CL, i.e. separate development from a common precursor. [ABSTRACT FROM AUTHOR]

Abundant macrophage infiltration in tumors often correlates with a poor prognosis. T cell/histiocyte rich large B cell lymphoma (THRLBCL) is a distinct aggressive B cell lymphoma entity showing a high macrophage content. To further elucidate the role of tumor-associated macrophages in THRLBCL, we performed gene expression profiling of microdissected histiocyte subsets of THRLBCL, nodular lymphocyte predominant Hodgkin lymphoma (NLPHL), Piringer lymphadenitis, sarcoidosis, nonspecific lymphadenitis and monocytes from peripheral blood. In a supervised principal component analysis, histiocytes from THRLBCL were most closely related to epithelioid cells from NLPHL, with both types of cells expressing genes related to proinflammatory and regulatory macrophage activity. Moreover, histiocytes from THRLBCL strongly expressed metal-binding proteins like MT2A, by which histiocytes of THRLBCL can be distinguished from the other histiocyte subsets investigated. Interestingly, the validation at the protein level showed a strong expression of TXN, CXCL9, MT2A and SOD2 not only in macrophages of THRLBCL but also in the tumor cells of NLPHL and classical Hodgkin lymphoma (cHL). Overall, the present findings indicate that macrophages in the microenvironment of THRLBCL have acquired a distinct gene expression pattern that is characterized by a mixed M1/M2 phenotype and a strong expression of several metal binding proteins. The microenvironments in NLPHL and THRLBCL appear to have a similar influence on the macrophage phenotype. The high expression of metal binding proteins in histiocytes of THRLBCL may be diagnostically useful, but a potential pathophysiological role remains to be identified. [ABSTRACT FROM AUTHOR]

Background Humanized mouse models for adoptive T cell transfer are important for preclinical efficacy and toxicity studies. However, common xenograft models using immunodeficient mice have so far failed to efficiently support the homing of human T cells to secondary lymphoid tissues. Methods We established a new mouse model for the adoptive transfer of genetically-modified (gm) T cells using conditioned BALB/c mice. Conditioning involved cyclophosphamide injections, lethal irradiation and radioprotection with bone marrow from immunodeficient mice. We compared repopulation kinetics and the quality of grafts in these modified Trimera (mT3) mice with immunodeficient BALB/c Rag2−/− interleukin (IL)2 receptor gamma (rg) knockout (DKO) and NOD/LtSz-scid IL2rg−/− (NSG) recipient mouse strains. Results DKO mice showed only marginal engraftment until onset of graft-versus-host disease, whereas mT3 and NSG were repopulated with comparable kinetics. However, T cell repertoire and human cytokine profiles suggest a xenoreactivity-driven gm T cell expansion in mT3 mice, whereas NSG mice were characterized by an initial homeostatic proliferation. Morphological analysis revealed high levels of human gm T cell infiltration in the spleen and liver of all three mouse strains. However, mT3 mice provided the strongest homing of human gm T cells to mucosal sites. Additionally, mT3 mice were the only model with macroscopically visible superficial inguinal lymph nodes. These lymph nodes strongly supported the homing of gm T cells. Conclusions In the present study, we give proof-of-concept that wild-type mice can accept gm T cell grafts while providing secondary lymphoid structures. Despite limitations, mT3 mice are a valid alternative for applications that specifically rely on improved secondary lymphoid structures. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hartmann S, Agostinelli C, Klapper W, Korkolopoulou P, Koch K, Marafioti T, Piccaluga P P, Patsouris E, Pileri S & Hansmann M-L (2011) Histopathology 59, 1173-1182 Revising the historical collection of epithelioid cell-rich lymphomas of the Kiel Lymph Node Registry: what is Lennert's lymphoma nowadays? Aims: Lennert's lymphoma is a rare variant of peripheral T-cell lymphoma (PTCL) not otherwise specified (NOS). The aim of this study was to further characterize this tumour. Methods and results: Historical material of 97 lymphomas with a high content of epithelioid cells, collected at the Kiel Lymph Node Registry were reviewed, by applying immunohistochemistry and current diagnostic criteria. Among all cases revised, various B-cell lymphoma entities (25 cases), Hodgkin lymphomas (21 cases) and PTCL subtypes (48 cases) could be identified. A distinctive subgroup of eight PTCLs was found that were regarded as genuine Lennert's lymphomas. These cases were characterized by mild atypia, a non-activated cytotoxic phenotype [TIA1 cytotoxic granule-associated RNA binding protein (TIA1)-positive+ and granzyme B-negative], and a substantial lack of follicular T-helper (TFH) cell markers. Among the other PTCLs, including angioimmunoblastic T-cell lymphoma and PTCL NOS, many cases with positivity for more than three TFH cell-associated molecules were recorded. Conclusions: Our study shows that, according to current criteria, Lennert's lymphoma is a rare but distinctive entity among epithelioid cell-rich lymphomas, differing on grounds of morphology and immunophenotype from other PTCL subtypes. An additional finding is the broad morphological spectrum of epithelioid-cell rich PTCLs showing a TFH cell phenotype. [ABSTRACT FROM AUTHOR]

Agostinelli C, Hartmann S, Klapper W, Korkolopoulou P, Righi S, Marafioti T, Piccaluga P P, Patsouris E, Hansmann M-L, Lennert K & Pileri S A (2011) Histopathology 59, 679-691 Peripheral T cell lymphomas with follicular T helper phenotype: a new basket or a distinct entity? Revising Karl Lennert's personal archive Aims: To revise 25 cases selected from Karl Lennert's personal archive (21) and Bologna and Frankfurt Registries (four) because of cytological similarities. Methods and results: All cases were provided with paraffin blocks and studied by immunohistochemistry and molecular techniques. While phenotyping was very informative, among molecular studies only EBER in situ-hybridization (ISH) was successful. Twenty-two cases were concluded as peripheral T cell lymphomas (PTCL). Of these, six were reclassified as angioimmunoblastic T cell lymphoma (AITL), 13 as PTCL, not otherwise specified (NOS), including four follicular variants and one tumour with T-zone pattern, and three as borderline tumours between AITL and PTCL/NOS. All these cases consisted homogeneously of small/medium-sized elements with mild nuclear atypia and an evident rim of clear/pale cytoplasm. On immunohistochemistry, they regularly expressed three to six follicular helper T cell (FTH)-associated markers. EBER-ISH revealed scattered EBV-infected B cells in all tumours except those with 'follicular' growth pattern. The content of follicular dendritic cells and high-endothelial venules varied significantly depending on the histotype. Conclusions: This study shows that: (i) historical material can be still employed usefully, and (ii) the FTH-phenotype corresponds to a broad spectrum of PTCLs that might form a new category to be validated in future molecular and clinicopathological analyses. [ABSTRACT FROM AUTHOR]

Little is known about genomic aberrations in peripheral T cell lymphoma, not otherwise specified (PTCL NOS). We studied 47 PTCL NOS by 250k GeneChip single nucleotide polymorphism arrays and detected genomic imbalances in 22 of the cases. Recurrent gains and losses were identified, including gains of chromosome regions 1q32–43, 2p15–16, 7, 8q24, 11q14–25, 17q11–21 and 21q11–21 (≥5 cases each) as well as losses of chromosome regions 1p35–36, 5q33, 6p22, 6q16, 6q21–22, 8p21–23, 9p21, 10p11–12, 10q11–22, 10q25–26, 13q14, 15q24, 16q22, 16q24, 17p11, 17p13 and Xp22 (≥4 cases each). Genomic imbalances affected several regions containing members of nuclear factor-kappaB signalling and genes involved in cell cycle control. Gains of 2p15–16 were confirmed in each of three cases analysed by fluorescence in situ hybridization (FISH) and were associated with breakpoints at the REL locus in two of these cases. Three additional cases with gains of the REL locus were detected by FISH among 18 further PTCL NOS. Five of 27 PTCL NOS investigated showed nuclear expression of the REL protein by immunohistochemistry, partly associated with genomic gains of the REL locus. Therefore, in a subgroup of PTCL NOS gains/rearrangements of REL and expression of REL protein may be of pathogenetic relevance. [ABSTRACT FROM AUTHOR]

Several tumour suppressor genes (TSG) have been identified as a result of mapping homozygous deletions in cancer cells. To identify putative TSG involved in the pathogenesis of classical Hodgkin lymphoma (cHL), we investigated four cHL cell lines (L428, HDLM2, KMH2, L1236) using four different array-Comparative Genomic Hybridisation (array-CGH) platforms and focused on high resolution identification of homozygous deletions. Out of 79 candidate regions of bi-allelic loss identified by array-CGH, besides previously described regions, 28 novel regions of homozygous deletions could be verified by polymerase chain reaction. These regions ranged from 13 kb to 619 kb in size. Eleven of the 28 novel bi-allelic losses were putative copy number polymorphisms. This left 17 regions that might harbour novel tumour suppressors involved in Hodgkin lymphoma. Expression profiling with two different platforms confirmed lack of expression of the majority of the genes located in the homozygous deletions. Furthermore, analysis of ontology annotations of genes located in the homozygously deleted regions indicated an enrichment of genes involved in apoptosis and cell death. In summary, through the mapping of homozygous deletions in cell lines this study identified a series of genes, such as SEPT9, GNG7 and CYBB, which might encode candidate tumour suppressors involved in the pathogenesis of cHL. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor (CAR) T cells brought substantial benefit to patients with B‐cell malignancies. Notwithstanding, CAR T‐cell manufacturing requires complex procedures impeding the broad supply chain. Here, we provide evidence that human CD19‐CAR T cells can be generated directly in vivo using the lentiviral vector CD8‐LV specifically targeting human CD8+ cells. Administration into mice xenografted with Raji lymphoma cells and human peripheral blood mononuclear cells led to CAR expression solely in CD8+ T cells and efficacious elimination of CD19+ B cells. Further, upon injection of CD8‐LV into mice transplanted with human CD34+ cells, induction of CAR T cells and CD19+ B‐cell depletion was observed in 7 out of 10 treated animals. Notably, three mice showed elevated levels of human cytokines in plasma. Tissue‐invading CAR T cells and complete elimination of the B‐lymphocyte‐rich zones in spleen were indicative of a cytokine release syndrome. Our data demonstrate the feasibility of in vivo reprogramming of human CD8+CAR T cells active against CD19+ cells, yet with similar adverse effects currently notorious in the clinical practice. Synopsis: T cells were reprogrammed with chimeric antigen receptors (CARs) in situ upon systemic injection of CD8‐targeted lentiviral vectors, thus providing proof‐of‐principle for converting CAR T cell therapy from an autologous, individualized to an off‐the‐shelf product. In situ CAR T cell generation was evidenced in mice transplanted with human PBMC or CD34+ stem cells.In situ generated CAR T cells expanded upon antigen recognition and eliminated CD19+ cells.Some mice developed side‐effects resembling the cytokine release syndrome observed in patients treated with CAR T cells. T cells were reprogrammed with chimeric antigen receptors (CARs) in situ upon systemic injection of CD8‐targeted lentiviral vectors, thus providing proof‐of‐principle for converting CAR T cell therapy from an autologous, individualized to an off‐the‐shelf product. [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma (MCL) is clinically and biologically heterogeneous. While various prognostic features have been proposed, none currently impact therapy selection, particularly in older patients, for whom treatment is primarily dictated by age and comorbidities. Herein, we undertook a comprehensive comparison of clinicopathological features in a cohort of patients 60 years and older, uniformly treated with bendamustine and rituximab, with a median survival of >8 years. The strongest prognostic indicators in this cohort were a high-risk call by a simplified MCL international prognostic index (s-MIPI) (HR: 3.32, 95% CI: 1.65-6.68 compared to low risk), a high-risk call by MCL35 (HR: 10.34, 95% CI: 2.37-45.20 compared to low risk) and blastoid cytology (HR: 4.21, 95% CR: 1.92-9.22 compared to classic). Patients called high risk by both the s-MIPI and MCL35 had the most dismal prognosis (HR: 11.58, 95% CI: 4.10-32.72), while those with high risk by either had a moderate but clinically relevant prognosis (HR: 2.95, 95% CI: 1.49-5.82). A robust assay to assess proliferation, such as MCL35, along with stringent guidelines for cytological evaluation of MCL, in combination with MIPI, may be a strong path to risk-stratify older MCL patients in future clinical trials., (© 2023 British Society for Haematology and John Wiley & Sons Ltd.)