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© 2019 Wiley Periodicals, Inc. The histological diagnosis of peripheral T-cell lymphoma (PTCL) can represent a challenge, particularly in the case of closely related entities such as angioimmunoblastic T-lymphoma (AITL), PTCL-not otherwise specified (PTCL-NOS), and ALK-negative anaplastic large-cell lymphoma (ALCL). Although gene expression profiling and next generations sequencing have been proven to define specific features recurrently associated with distinct entities, genomic-based stratifications have not yet led to definitive diagnostic criteria and/or entered into the routine clinical practice. Herein, to improve the current molecular classification between AITL and PTCL-NOS, we analyzed the transcriptional profiles from 503 PTCLs stratified according to their molecular configuration and integrated them with genomic data of recurrently mutated genes (RHOA G17V , TET2, IDH2 R172 , and DNMT3A) in 53 cases (39 AITLs and 14 PTCL-NOSs) included in the series. Our analysis unraveled that the mutational status of RHOA G17V , TET2, and DNMT3A poorly correlated, individually, with peculiar transcriptional fingerprints. Conversely, in IDH2 R172 samples a strong transcriptional signature was identified that could act as a surrogate for mutational status. The integrated analysis of clinical, mutational, and molecular data led to a simplified 19-gene signature that retains high accuracy in differentiating the main nodal PTCL entities. The expression levels of those genes were confirmed in an independent cohort profiled by RNA-sequencing.

Even in the era of highly active combination antiretroviral therapy (cART), patients with HIV have a disproportionate risk of developing aggressive lymphomas that are frequently Epstein-Barr virus (EBV)-related. Here, we investigate HIV-associated diffuse large B-cell lymphoma (HIV-DLBCL) and compare EBV-positive and EBV-negative cases. HIV-DLBCL were identified from two academic medical centres and characterised by immunohistochemistry, EBV status, fluorescence in situ hybridisation, cell of origin determination by gene expression profiling, and targeted deep sequencing using a custom mutation panel of 334 genes. We also applied the Lymphgen tool to determine the genetic subtype of each case. Thirty HIV-DLBCL were identified, with a median patient age of 46 years and male predominance (5:1). Thirteen cases (48%) were EBV-positive and 14 (52%) EBV-negative. Nine of the 16 tested cases (56%) had MYC rearrangement, three (19%) had BCL6 (two of which were double hit MYC/BCL6) and none had BCL2 rearrangements. Using the Lymphgen tool, half of the cases (15) were classified as other. All HIV-DLBCL showed mutational abnormalities, the most frequent being TP53 (37%), MYC (30%), STAT3 (27%), HIST1H1E (23%), EP300 (20%), TET2 (20%), SOCS1 (17%) and SGK1 (17%). EBV-negative cases were mostly of germinal centre B-cell (GCB) origin (62%), showed more frequent mutations per case (a median of 13·5/case) and significant enrichment of TP53 (57% vs. 15%; P = 0·046), SGK1 (36% vs. 0%; P = 0·04), EP300 (43% vs. 0%; P = 0·02) and histone-modifying gene (e.g. HIST1H1E, HIST1H1D, 79% vs. 31%; P = 0·02) mutations. EBV-positive cases were mostly of non-GCB origin (70%), with fewer mutations per case (median 8/case; P = 0·007), and these tumours were enriched for STAT3 mutations (P = 0·10). EBV-positive cases had a higher frequency of MYC mutations but the difference was not significant (36% vs. 15%; P = 0·38). EBV-association was more frequent in HIV-DLBCLs, arising in patients with lower CD4 counts at diagnosis (median 46·5 vs. 101, P = 0·018). In the era of cART, approximately half of HIV-DLBCL are EBV-related. HIV-DLBCL are enriched for MYC rearrangements, MYC mutations and generally lack BCL2 rearrangements, regardless of EBV status. Among HIV-DLBCL, tumours that are EBV-negative and EBV-positive appear to have important differences, the latter arising in context of lower CD4 count, showing frequent non-GCB origin, lower mutation burden and recurrent STAT3 mutations.

Funder: Airbus Endeavr Wales, Funder: Alexander von Humboldt Foundation, When designing spacefaring vehicles and orbital instrumentation, the onboard systems such as microelectronics and solar cells require shielding to protect them from degradation brought on by collisions with high‐energy particles. Perovskite solar cells (PSCs) have been shown to be much more radiation stable than Si and GaAs devices, while also providing the ability to be fabricated on flexible substrates. However, even PSCs have their limits, with higher fluences being a cause of degradation. Herein, a novel solution utilizing a screen‐printed, mesoporous carbon electrode to act bi‐functionally as an encapsulate and the electrode is presented. It is demonstrated that the carbon electrode PSCs can withstand proton irradiation up to 1 × 1015 protons cm−2 at 150 KeV with negligible losses (

Nonfullerene acceptors (NFAs) dominate organic photovoltaic (OPV) research due to their promising efficiencies and stabilities. However, there is very little investigation into the molecular processes of degradation, which is critical to guiding design of novel NFAs for long‐lived, commercially viable OPVs. Here, the important role of molecular structure and conformation in NFA photostability in air is investigated by comparing structurally similar but conformationally different promising NFAs: planar O‐IDTBR and nonplanar O‐IDFBR. A three‐phase degradation process is identified: i) initial photoinduced conformational change (i.e., torsion about the core–benzothiadiazole dihedral), induced by noncovalent interactions with environmental molecules, ii) followed by photo‐oxidation and fragmentation, leading to chromophore bleaching and degradation product formation, and iii) finally complete chromophore bleaching. Initial conformational change is a critical prerequisite for further degradation, providing fundamental understanding of the relative stability of IDTBR and IDFBR, where the already twisted IDFBR is more prone to degradation. When blended with the donor polymer poly(3‐hexylthiophene), both NFAs exhibit improved photostability while the photostability of the polymer itself is significantly reduced by the more miscible twisted NFA. The findings elucidate the important role of NFA molecular structure in photostability of OPV systems, and provide vital insights into molecular design rules for intrinsically photostable NFAs.

The authors gratefully acknowledge funding from supported by KAUST under the Grant Agreement number OSR-2015-CRG4-2572 and the EPSRC/GCRF project SUNRISE (EP/P032591/1). H.C. acknowledges Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2018R1A6A3A03011245). J.Z. acknowledges a Ph.D. scholarship from China Scholarship Council (201503170255). H. H. Lee acknowledges SRC program through National Research Foundation of Korea (NRF) funded by the Korean government (NRF-2015R1A5A1009962). A.A.B is a Royal Society University Research Fellow.

Aim No oral niche can be considered to be segregated from the subjacent milieu because of the complex community behavior and nature of the oral biofilms. The aim of this study was to address the paucity of information on how these species are clonally related to the subjacent gingival crevice bacteria. Methods We utilized a metagenomic approach of amplifying 16S rDNA from genomic DNA, cloning, sequencing and analysis using LIBSHUFF software to assess the genetic homogeneity of the bacterial species from two infected root canals and subjacent gingival crevices. Results The four niches studied yielded 186 clones representing 54 phylotypes. Clone library comparisons using LIBSHUFF software indicated that each niche was inhabited by a unique flora. Further, 42% of the clones were of hitherto unknown phylotypes indicating the extent of bacterial diversity, especially in infected root canals and subjacent gingival crevices. Conclusions We believe data generated through this novel analytical tool shed new light on understanding oral microbial ecosystems.

Summary Few studies have examined the value of a mandatory second review of outside pathology material for haematological malignancies. Therefore, we compared diagnoses on biopsies referred to an academic medical centre to determine the rate and therapeutic impact of revised diagnoses resulting from a second review. We reviewed 1010 cases referred for lymphoma during 2009–2010. For each case, referral diagnosis and second review diagnosis were compared. Revised diagnoses were grouped into major and minor discrepancies and all major discrepancies were reviewed by a haematologist to determine the effect the diagnostic change would have on therapy. There was no change in diagnosis in 861 (85·2%) cases. In 149 (14·8%) cases, second review resulted in major diagnostic change, of which 131 (12·9%) would have resulted in a therapeutic change. The highest rates of revision were for follicular, high-grade B-cell, and T-cell lymphomas. We found higher rates of major discrepancy in diagnoses from non-academic centres (15·8%) compared to academic centres (8·5%; P = 0·022), and in excisional biopsies (17·9%) compared to smaller biopsies (9·6%; P = 0·0003). Mandatory review of outside pathology material prior to treatment of patients for lymphoma will identify a significant number of misclassified cases with a major change in therapy.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease and "double-hit" DLBCL, with both MYC and BCL2 translocations has a poor prognosis. In this study, we investigated whether MYC and BCL2 protein expression in tissue would predict survival in DLBCL. The study included 106 cases of de novo DLBCL treated with rituximab and cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) or CHOP-like regimens. The results were validated on an independent cohort of 205 DLBCL patients. Patients with low expression of BCL2 (≤30%) and MYC (≤50%) had the best prognosis, whereas those with high BCL2 (>30%) and MYC (>50%) had the worst outcome. In multivariate analysis, the combination of the BCL2 and MYC was an independent predictor of overall survival (OS) and event-free survival (EFS) (P = 0·015 and P = 0·005, respectively). The risk of death was nine times greater for patients with high BCL2 and MYC compared to those with low expression. High BCL2 and MYC was a strong predictor of poor OS (P < 0·001) and EFS (P = 0·0017) in patients with the germinal centre B-cell (GCB) type, but not in the non-GCB type. In DLBCL, high co-expression of MYC and BCL2 was an independent predictor of poor survival, and could be used to stratify patients for risk-adapted therapies.

Summary We evaluated the prognostic significance of CD43 (SPN), a membrane glycoprotein, in 140 patients with diffuse large B-cell lymphoma (DLBCL) by tissue microarray (TMA) immunostaining, and gene expression profiling (GEP) in 43 patients. CD43 protein was expressed in 19% of the cases and was strongly related to the non-germinal centre B-cell (non-GCB) subgroup by both TMA and GEP. Patients with CD43(+) DLBCL had an inferior 3-year overall survival (OS) compared to those with CD43(-) DLBCL (50% vs. 76%, P = 0·01). Within the non-GCB subgroup, patients with CD43(+) DLBCL had a particularly poor 3-year OS (32% vs. 71%, P

There is a high incidence of genomic aberration of ataxia telangiectasia mutated (ATM) and genes encoding proteins involved in the ATM pathway in mantle cell lymphoma (MCL). It has been shown that poly(ADP-ribose) polymerase inhibitor (PARPi) strongly enhances the cytotoxicity of agents, causing single-strand DNA breaks in cells with impaired homologous recombination repair. Here, we show that PARPi AG14361 potentiates the cytotoxicity induced by topotecan treatment in MCL cell lines, which was not dependent on either TP53 or CHEK2 status. Inhibition and/or knockdown of ATM and BRCA2 did not potentiate the cytotoxic effect of treatment with PARPi and topotecan. With loss of function of ATM, other kinases can still mediate activation of ATM substrates as demonstrated by continued phosphorylation of CHEK2 (Thr-68), although attenuated and delayed. These results suggest that PARPi may enhance the therapeutic efficacy of DNA damaging agents on MCL through TP53-independent mechanisms without requiring the inhibition of either ATM or BRCA2.

Diffuse large B-cell lymphoma (DLBCL) includes two prognostically important subtypes, the germinal center B-cell (GCB) and the non-GCB types. The aim of this study was to evaluate immunohistochemical approaches for predicting the survival of patients with DLBCL following autologous hematopoietic stem cell transplantation (AHSCT). We identified 62 patients with DLBCL who either had an initial complete remission (17 patients) or received salvage chemotherapy for relapsed or refractory disease (45 patients), followed by AHSCT. Tissue microarrays were immunostained with monoclonal antibodies against GCET1, CD10, BCL6, MUM1, FOXP1 and LMO2. Using the Hans algorithm, we classified 50% of the cases as GCB type, whereas the Choi algorithm classified 58% as GCB type and LMO2 was positive in 69%. However, no significant differences were found in the 5-year overall or event-free survivals using any of these approaches. In conclusion, cell of origin fails to predict survival of DLBCL patients treated with AHSCT.

Despite recent therapeutic improvements, the clinical course of diffuse large B-cell lymphoma (DLBCL) still differs considerably among patients. We conducted this retrospective multi-centre study to evaluate the impact of genomic aberrations detected using a high-density genome wide-single nucleotide polymorphism-based array on clinical outcome in a population of DLBCL patients treated with R-CHOP-21 (rituximab, cyclophosphamide, doxorubicine, vincristine and prednisone repeated every 21 d). 166 DNA samples were analysed using the GeneChip Human Mapping 250K NspI. Genomic anomalies were analysed regarding their impact on the clinical course of 124 patients treated with R-CHOP-21. Unsupervised clustering was performed to identify genetically related subgroups of patients with different clinical outcomes. Twenty recurrent genetic lesions showed an impact on the clinical course. Loss of genomic material at 8p23.1 showed the strongest statistical significance and was associated with additional aberrations, such as 17p- and 15q-. Unsupervised clustering identified five DLBCL clusters with distinct genetic profiles, clinical characteristics and outcomes. Genetic features and clusters, associated with a different outcome in patients treated with R-CHOP, have been identified by arrayCGH.

Summary Post-transplant lymphoproliferative disorders (PTLD) are complications of solid organ transplantation associated with severe morbidity and mortality. Diffuse large B-cell lymphoma (DLBCL) represents the most common form of monomorphic PTLD. We studied 44 cases of post-transplant DLBCL (PT-DLBCL) with high-density genome wide single nucleotide polymorphism-based arrays, and compared them with 105 cases of immunocompetent DLBCL (IC-DLBCL) and 28 cases of Human Immunodeficiency Virus-associated DLBCL (HIV-DLBCL). PT-DLBCL showed a genomic profile with specific features, although their genomic complexity was overall similar to that observed in IC- and HIV-DLBCL. Among the loci more frequently deleted in PT-DLBCL there were small interstitial deletions targeting known fragile sites, such as FRA1B, FRA2E and FRA3B. Deletions at 2p16.1 (FRA2E) were the most common lesions in PT-DLBCL, occurring at a frequency that was significantly higher than in IC-DLBCL. Genetic lesions that characterized post-germinal center IC-DLBCL were under-represented in our series of PT-DLBCL. Two other differences between IC-DLBCL and PT-DLBCL were the lack of del(13q14.3) (MIR15/MIR16) and of copy neutral LOH affecting 6p [major histocompatibility complex (MHC) locus] in the latter group. In conclusion, PT-DLBCL presented unique features when compared with IC-DLBCL. Changes in PT-DLBCL were partially different to those in HIV-DLBCL, suggesting different pathogenetic mechanisms in the two conditions linked to immunodeficiency.

In this report, highly efficient and humidity‐resistant perovskite solar cells (PSCs) using two new small molecule hole transporting materials (HTM) made from a cost‐effective precursor anthanthrone (ANT) dye, namely, 4,10‐bis(1,2‐dihydroacenaphthylen‐5‐yl)‐6,12‐bis(octyloxy)‐6,12‐dihydronaphtho[7,8,1,2,3‐nopqr]tetraphene (ACE‐ANT‐ACE) and 4,4′‐(6,12‐bis(octyloxy)‐6,12‐dihydronaphtho[7,8,1,2,3‐nopqr]tetraphene‐4,10‐diyl)bis(N,N‐bis(4‐methoxyphenyl)aniline) (TPA‐ANT‐TPA) are presented. The newly developed HTMs are systematically compared with the conventional 2,2′,7,7′‐tetrakis(N,N′‐di‐p‐methoxyphenylamino)‐9,9′‐spirbiuorene (Spiro‐OMeTAD). ACE‐ANT‐ACE and TPA‐ANT‐TPA are used as a dopant‐free HTM in mesoscopic TiO2/CH3NH3PbI3/HTM solid‐state PSCs, and the performance as well as stability are compared with Spiro‐OMeTAD‐based PSCs. After extensive optimization of the metal oxide scaffold and device processing conditions, dopant‐free novel TPA‐ANT‐TPA HTM‐based PSC devices achieve a maximum power conversion efficiency (PCE) of 17.5% with negligible hysteresis. An impressive current of 21 mA cm−2 is also confirmed from photocurrent density with a higher fill factor of 0.79. The obtained PCE of 17.5% utilizing TPA‐ANT‐TPA is higher performance than the devices prepared using doped Spiro‐OMeTAD (16.8%) as hole transport layer at 1 sun condition. It is found that doping of LiTFSI salt increases hygroscopic characteristics in Spiro‐OMeTAD; this leads to the fast degradation of solar cells. While, solar cells prepared using undoped TPA‐ANT‐TPA show dewetting and improved stability. Additionally, the new HTMs form a fully homogeneous and completely covering thin film on the surface of the active light absorbing perovskite layers that acts as a protective coating for underlying perovskite films. This breakthrough paves the way for development of new inexpensive, more stable, and highly efficient ANT core based lower cost HTMs for cost‐effective, conventional, and printable PSCs.

Liquid-crystal (LC) gels are normally used as insulating, scattering media in LC displays. Organic solar cells generate electrical power by the separation of photocreated electrons and holes at the interface between electron-donating and electron-accepting organic semiconductors. We combine these two technologies to create a new type of plastic solar cell. The efficiency of solar cells can be improved by enlarging the interface area to maximize charge separation and by vertically separating the two materials to provide different paths for electrons and holes to the electrodes. We use a new electron-donating, visible-light absorbing, LC gel to form a surface with nanometer-sized grooves with a large interface area to an overlying electron-accepting layer. This forms a photovoltaic cell, which exhibits a monochromatic power conversion efficiency of 0.6 % at an incident intensity of 45 mW cm. Improvements will provide low-cost, robust solar cells compatible with plastic electronics and roll-to-roll processing. Most organic photovoltaics use either main-chain conjugated polymers, often in conjunction with fullerenes, or low-molecular-weight glasses, achieving power-conversion efficiencies up to 4.2 %. Charge separation is achieved in solar cells by ionization of the photogenerated exciton at a heterointerface between electron-donating material with a low ionization potential (IP) and electron-accepting species with a high electron affinity (EA). The diffusion length of the exciton before recombination is of the order of 100–200 A, so that distributed, rather than planar, heterointerfaces have been used to maximize charge separation. These have been formed by phase-separated blends of electron-donating and electronaccepting organic materials. The bulk-distributed heterojunctions are formed randomly and do not guarantee a continuous pathway for charge carriers to the electrodes. The required vertical segregation of the blend materials can be obtained by surface treatment or in diffuse bilayer photovoltaics. A blend of an electron-donating columnar LC, hexabenzocoronene, and an electron-accepting perylene dye vertically segregates spontaneously to give an efficient photovoltaic effect. Unfortunately, the spatial scale of the phase separation cannot be controlled reproducibly in these devices. Another problem for phase-separated configurations is poor stability of the domain size lowering the device efficiency. To date the photovoltaic effect has only been demonstrated with calamitic LCs via an ionic mechanism, although electronic photoconductivity has been well researched. Polymerizable LCs, with two polymerizable groups attached through flexible aliphatic spacers to an aromatic core, are attracting interest as organic semiconductors for electroluminescence and organic transistors. Their advantages include spontaneous self-assembly, relatively high charge mobility (1 × 10 cm V s), easy deposition by spin-coating or ink-jet printing and lithographic photopatterning to form multilayer polymer networks. We now report the use of reactive mesogens in a novel way to demonstrate a new approach to photovoltaics. Liquid-crystalline gels are formed from a homogeneous mixture of a reactive mesogen and a non-polymerizable LC. Polymerization results in controlled phase separation of the two components and the formation of a polymer network matrix around the nematic droplets. To date, transparent LC gels have typically been used in direct-view reflective displays, switchable polarizers, directional reflectors, and so forth. Polymerization-induced phase separation of a homogeneous mixture of a LC and a polymer-forming material brings the concept of a paintable display closer. A key step in our new approach is the use of mixtures of hole-transporting reactive mesogens with a low IP and analogous LCs with the same aromatic core to form an electron-donating LC gel. An ideal LC composite photovoltaic is illustrated in Figure 1. It has a vertically separated, large-area interface between electron-donating and electron-accepting layers providing complete pathways for transport of holes and electrons. An electron-blocking polymer network of the electron-donating reactive mesogen is deposited first on an electrode surface by spin-coating from solution and then crosslinking in order to provide a high open circuit. A mixture of the same electron-donating reactive mesogen and the corresponding non-polymerizable analogue are then deposited in a similar C O M M U N IC A TI O N S

Graphene nanoparticles have been subject to intensive investigation as a replacement for platinum as the catalyst in dye sensitized solar cells (DSCs), but few of these investigations examine the application for flexible cells with deposition processes suitable for industrial fabrication. This work introduces a transparent water based graphene ink that can be dried rapidly at less than 110 oC making it particularly suitable for roll to roll deposition on plastic substrates. This ink has application as a catalyst for dye sensitized solar cells utilizing cobalt complex electrolytes with efficiency of over 6 % and a Voc of 0.89 V at 1 sun demonstrated. A flexible DSC with a printed catalyst and cobalt redox mediator is reported, with efficiency of over 6.0 % and Voc of 0.6 V at 800 lux.

Although mantle cell lymphoma (MCL) is considered a distinctive disease entity within non-Hodgkin's lymphoma (NHL), the cytology and growth pattern of MCL can be quite variable and the clinical significance of these features is unclear. Also, the role of anthracyclines in the management of MCL is unclear. Therefore, we examined our experience with MCL in an effort to clarify these important issues. We identified 68 patients with MCL who were evaluated clinically and treated by the Nebraska Lymphoma Study Group. Treatment consisted of combination chemotherapy containing an anthracycline in 76% of the patients. The cases were grouped by blastic or lymphocytic cytology, and the latter were divided by growth pattern into nodular (or mantle-zone) and diffuse types. The clinical and pathological variables were then evaluated for their prognostic value. The median overall survival (OS) and failure-free survival (FFS) for the entire group were 38 months and 12 months, respectively, and there was no survival advantage for those who received an anthracycline. The cases were grouped as follows: blastic type, 26%; nodular lymphocytic type, 44%; and diffuse lymphocytic type, 30%. Both the cytology and pattern of growth were predictive of OS and FFS. The median OS was as follows: blastic type, 55 months; nodular lymphocytic type, 50 months; and diffuse lymphocytic type, 16 months (P = 0.0038). The clinical features that predicted for a shorter survival included bone marrow involvement, advanced stage disease, B symptoms, a poor performance score, and the International Prognostic Index. We conclude that new therapeutic approaches, with the patients stratified by histologic type and clinical prognostic factors, are clearly needed for MCL.

Herein a clinical case of an unusual metastasis from breast cancer to the retina and vitreous confirmed by diagnostic vitrectomy is described. Further investigation also demonstrated the central nervous system metastasis.

A feasible architecture is proposed for implementing synchronous all-optical code-division multiple-access (CDMA) networks with full channel tunability. The proposed network uses fastly programmable all-optical CDMA encoders and decoders which are based on tunable optical delay-lines and require only a small number of electro-optic switches. Coding and decoding algorithms for “synchronous” prime-sequence codes that can be rapidly performed in the optical domain are described. Moreover, a two-wavelength scheme is presented to effectively solve the problems associated with clock distribution and frame synchronization in large-scale synchronous CDMA networks. By using the proposed technique, all-optical CDMA transmitters and receivers can be constructed with integrated optics and can achieve a very high processing speed.

Globoid cell leukodystrophy (GLD) or Krabbe disease is a devastating, degenerative neurological disorder caused by mutations in the galactosylceramidase (GALC) gene that severely affect enzyme activity. Currently, treatment options for this disorder are very limited. Enzyme replacement therapy (ERT) has been shown to be effective in lysosomal storage disorders with predominantly peripheral manifestations such as type I Gaucher's and Fabry's disease. Little however is known about the possible benefit of ERT in GLD, which has a substantial central nervous system component. In this study, we examined the effect of peripheral GALC injections in the twitcher mouse model of the disease. Although we were unable to block the precipitous decline that normally occurs just before death, we did observe significant early improvements in motor performance, a substantial attenuation in the initial failure to thrive, and an increase in life span. Immunohistochemical and activity analyses demonstrated GALC uptake in multiple tissues, including the brain. This was associated with a decrease in the abnormal accumulation of the GALC substrate psychosine, which is thought to play a pivotal role in disease pathology. These results indicate that peripheral ERT is likely to be beneficial in GLD.

Mantle cell lymphoma (MCL) is a B-cell neoplasm with an aggressive clinical behavior characterized by the t(11;14)(q13;q32) and cyclin D1 overexpression. To clarify the potential contribution of altered DNA methylation in the development and/or progression of MCL, we performed genome-wide methylation profiling of a large cohort of primary MCL tumors (n = 132), MCL cell lines (n = 6) and normal lymphoid tissue samples (n = 31), using the Infinium HumanMethylation27 BeadChip. DNA methylation was compared to gene expression, chromosomal alterations and clinicopathological parameters. Primary MCL displayed a heterogeneous methylation pattern dominated by DNA hypomethylation when compared to normal lymphoid samples. A total of 454 hypermethylated and 875 hypomethylated genes were identified as differentially methylated in at least 10% of primary MCL. Annotation analysis of hypermethylated genes recognized WNT pathway inhibitors and several tumor suppressor genes as frequently methylated, and a substantial fraction of these genes (22%) showed a significant downregulation of their transcriptional levels. Furthermore, we identified a subset of tumors with extensive CpG methylation that had an increased proliferation signature, higher number of chromosomal alterations and poor prognosis. Our results suggest that a subset of MCL displays a dysregulation of DNA methylation characterized by the accumulation of CpG hypermethylation highly associated with increased proliferation that may influence the clinical behavior of the tumors.

BACKGROUND Polymerase chain reaction (PCR) based assays are becoming more reliable, simpler, and faster alternatives to traditional Southern blot hybridization (SBH) analysis for the detection of clonal immunoglobulin heavy chain (IgH) gene rearrangements. However, a variety of technical approaches have been reported with markedly different results. METHODS We analyzed the frozen tissue of 147 neoplastic and hyperplastic lesions on which SBH had previously been performed. Semi-nested and single-step PCR methods were compared. Consensus primers to the joining segments and the framework region (FR) III of the variable segments of the IgH gene were used. All PCR products were analyzed by polyacrylamide gel electrophoresis (PAGE). Thirteen samples were re-analyzed using a denaturing gradient gel electrophoresis (DGGE) system. RESULTS The overall concordance between SBH and semi-nested PCR assays was 80.2%. In the non-Hodgkin's lymphoma (NHL) group, 75% of the cases with IgH rearrangements by SBH were found to be monoclonal by PCR. Regardless of type of lesion, 71.7% of the cases with IgH rearrangements by SBH were found to be clonal by PCR. The concordance between the semi-nested and single-step procedures was 87.1%. DGGE was helpful in clarifying the results for cases in which the PAGE analysis was difficult to interpret. CONCLUSIONS PCR analysis of IgH gene rearrangements was found to be an efficient technique for the initial determination of clonality in lymphoid proliferations. The single-step method had an advantage over the semi-nested method because of its simplicity and speed. The DGGE system was useful for the assessment of clonality in cases with equivocal results after PAGE. However, a combination of these techniques in specific cases may achieve higher specificity and sensitivity. Cancer 1996;77:1349-55.

Background. A 63-year-old male presented with fever, a subcutaneous nodule, gingival hypertrophy, lacrimal gland enlargement, and no lymphadenopathy or hepatosplenomegaly, but had anemia, thrombocytopenia, and peripheral blood (PB) plus bone marrow (BM) involvement by leukemic cells. There was minimal response to multiagent chemotherapy and local radiotherapy, with a survival of 6.5 months from disease diagnosis. Methods. The PB and/or BM leukemic cells were evaluated using electron microscopy (EM), immunohistochemistry, flow-cytometric immunophenotyping, cytochemistry, cytogenetics, Southern blot analysis for gene rearrangement and Epstein-Barr virus (EBV), polymerase chain reaction for EBV and human herpes virus-6 (HHV-6), and in vitro culturing with inducing agents. Results. The leukemic cells were agranular and monocytoid, with a hairy cell-like bone marrow biopsy infiltrate. Myeloperoxidase (MPO) and alpha-naphthyl butyrate esterase staining was negative, and periodic acid-Schiff staining was positive by light microscopy. Electron microscopy showed MPO negativity and a lack of parallel tubular arrays. The immunophenotype was CD3-, CD56+, CD4+, CD8-, CD15+, TCR1-, and TCR2-, with germline immunoglobulin and T-cell receptor genes and an abnormal karyotype (44XY, 5q-, -13, 13q+, -15). No genomic material for EBV or HHV-6 was detected. Cell cultures with butyrate and N,N-hexamethylene bis-acetamide suggested the possible induction of tumor cells to express a T-cell immunophenotype. Conclusion. A case of clonal acute natural killer (NK) cell leukemia with an unusual morphology (agranular) and unique phenotype (CD3-, CD56+, CD4+, CD15+) is presented. Unlike as in other acute NK leukemias, EBV was negative ; there was no evidence of HHV-6. The tumor cell, after culturing with differentiating agents, may have been induced to express a T-cell immunophenotype. Cancer1995; 75 :2474-83.