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Overexpression of the BCL2 protein has been reported as a poor prognostic factor for diffuse large B-cell lymphoma (DLBCL). However, there are currently no standardized criteria for evaluating BCL2 protein expression. We aimed to evaluate the prognostic value of BCL2 expression determined by immunohistochemistry (IHC), incorporating both the staining intensity and proportion, in patients with de novo DLBCL who received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) as first-line treatment. We defined tumors with BCL2 expression in nearly all tumor cells with a uniformly strong intensity by IHC as BCL2 super-expressor. The BCL2 super-expressors (n = 35) showed significantly worse event-free survival (EFS; HR, 1.903; 95% CI, 1.159-3.126, P = 0.011) and overall survival (OS; HR, 2.467; 95% CI, 1.474-4.127, P = 0.001) compared with the non-BCL2 super-expressors (n = 234) independent of the international prognostic index (IPI), cell of origin (COO), and double expressor status in the training set (n = 269). The adverse prognostic impact of BCL2 super-expression was confirmed in the validation set (n = 195). When the survival outcomes were evaluated in the entire cohort (n = 464), BCL2 super-expressor group was significantly associated with inferior EFS and OS regardless of IPI, COO, MYC expression, and stages. BCL2 super-expressors had genetic aberrations enriched in the NOTCH and TP53 signaling pathways. This study suggests that the BCL2 super-expressor characterizes a distinct subset of DLBCL with a poor prognosis and warrants further investigation as a target population for BCL-2 inhibitors., (© 2021. The Author(s), under exclusive licence to United States & Canadian Academy of Pathology.)

Follicular dendritic cells are important stromal components of the germinal center (GC) and have pivotal roles in maintaining the GC microenvironment for high-affinity antibody production. Tumor necrosis factor- α (TNF α ) is essential for the development and functions of follicular dendritic cells. Despite the importance of follicular dendritic cells in humoral immunity, their molecular control mechanisms have yet to be fully elucidated due to the lack of an adequate investigation system. Here, we have used a unique human primary follicular dendritic cell-like cell (FDCLC) to demonstrate that the migration of these cells is enhanced by TNF α -mediated metalloproteinase 3 (MMP3) expression. MMP3 was found to be highly expressed in normal human GCs and markedly upregulated in human primary FDCLCs by TNF α . TNF α induced ERK1/2 phosphorylation and the transcription of MMP3 through AP1. TNF α treatment increased FDCLC migration, and a knockdown of MMP3 significantly reduced the TNF α -induced migration of FDCLCs. Overall, we have newly identified a control mechanism for the expression of MMP3 in FDCLCs that modulates their migration and may indicate an important role in GC biology. Since GCs are observed in the lesions of autoimmune diseases and lymphomas, targeting the MMP3/TNF α -mediated migration of stromal cells in the B cell follicle may have great potential as a future therapeutic modality against aberrant GC-associated disorders., Competing Interests: The authors declare no competing interests in relation to this article., (Copyright © 2021 Hyo-Kyung Pak et al.)

BCL2 overexpression has been reported to be associated with poor prognosis in patients with diffuse large B-cell lymphoma (DLBCL). However, currently there is no consensus on the evaluation of BCL2 expression and only the proportion of BCL2 positive cells are evaluated for the determination of BCL2 positivity. This study aimed to define BCL2 positivity by quantitative analysis integrating both the intensity and proportion of BCL2 expression. BCL2 expression of 332 patients (221 patients for the training set and 111 patients for the validation set) with newly diagnosed DLBCL who received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) were analyzed using the tumor-specific automated quantitative analysis (AQUA) scoring method based on multiplex immunofluorescence. In the training set, high BCL2 AQUA score (N = 86, 38.9%) was significantly associated with poor prognosis (p = 0.01, HR 2.00; 95% CI [1.15-3.49]) independent of international prognostic index, cell of origin, and MYC expression. The poor prognostic impact of the high BCL2 AQUA score was validated in the validation set. AQUA scoring of BCL2 expression incorporating both the intensity and proportion of BCL2 positive cells was independently associated with survival outcomes of patients with primary DLBCL treated with R-CHOP.

The risk stratification of diffuse large B-cell lymphoma (DLBCL) is crucial. The International Prognostic Index, the most commonly used and the traditional risk stratification system, is composed of fixed and artificially dichotomized attributes. We aimed to develop a novel prognostic model that allows the incorporation of up-to-date attributes comprehensively without information loss. We analyzed 204 patients with primary DLBCL who were uniformly treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) from 2007 to 2012 at Asan Medical Center. Using the multivariable fractional polynomial (MFP) method and bootstrap resampling, we selected the variables of significance and the best fitted functional form in fractional polynomials. Age, serum β2-microglobulin, serum lactate dehydrogenase, and BCL2 expression were selected as significant variables in predicting overall survival (OS), while age was excluded in predicting 2-years event-free survival. The prognostic score calculated by the MFP model effectively classifies patients into four risk groups with 5-years OS of 89.91% (low risk), 81.21% (low-intermediate risk), 66.40% (high-intermediate risk), and 37.89% (high risk). We suggest a new prognostic model that is simple and flexible. By using the MFP method, we can incorporate various clinicopathologic factors into a risk stratification system without arbitrary dichotomization., (Copyright © 2020 Roh, Jung, Lee, Kim, Pak, Lee, Lee, Cho, Cho, Yoon, Park, Huh, Oh and Park.)

Understanding noisy information engines is a fundamental problem of non-equilibrium physics, particularly in biomolecular systems agitated by thermal and active fluctuations in the cell. By the generalized second law of thermodynamics, the efficiency of these engines is bounded by the mutual information passing through their noisy feedback loop. Yet, direct measurement of the interplay between mutual information and energy has so far been elusive. To allow such examination, we explore here the entire phase-space of a noisy colloidal information engine, and study efficiency fluctuations due to the stochasticity of the mutual information and extracted work. We find that the average efficiency is maximal for non-zero noise level, at which the distribution of efficiency switches from bimodal to unimodal, and the stochastic efficiency often exceeds unity. We identify a line of anomalous, noise-driven equilibrium states that defines a refrigerator-to-heater transition, and test the generalized integral fluctuation theorem for continuous engines.

Sequencing studies of diffuse large B cell lymphoma (DLBCL) have identified hundreds of recurrently altered genes. However, it remains largely unknown whether and how these mutations may contribute to lymphomagenesis, either individually or in combination. Existing strategies to address this problem predominantly utilize cell lines, which are limited by their initial characteristics and subsequent adaptions to prolonged in vitro culture. Here, we describe a co-culture system that enables the ex vivo expansion and viral transduction of primary human germinal center B cells. Incorporation of CRISPR/Cas9 technology enables high-throughput functional interrogation of genes recurrently mutated in DLBCL. Using a backbone of BCL2 with either BCL6 or MYC, we identify co-operating genetic alterations that promote growth or even full transformation into synthetically engineered DLBCL models. The resulting tumors can be expanded and sequentially transplanted in vivo, providing a scalable platform to test putative cancer genes and to create mutation-directed, bespoke lymphoma models.

The ability to create and manipulate spatio-temporal potentials is essential in the diverse fields of science and technology. Here, we introduce an optical feedback trap system based on high precision position detection and ultrafast feedback control of a Brownian particle in the optical tweezers to generate spatio-temporal virtual potentials of the desired shape in a controlled manner. As an application, we study the nonequilibrium fluctuation dynamics of the particle in a time-varying virtual harmonic potential and validate the Crooks fluctuation theorem in the highly nonequilibrium condition.

We present an experimental realization of an information-driven Brownian motor by periodically cooling a Brownian particle trapped in a harmonic potential connected to a single heat bath, where cooling is carried out by the information process consisting of measurement and feedback control. We show that the random motion of the particle is rectified by symmetry-broken feedback cooling where the particle is cooled only when it resides on the specific side of the potential center at the instant of measurement. Studying how the motor thermodynamics depends on cycle period τ relative to the relaxation time τ B of the Brownian particle, we find that the ratcheting of thermal noise produces the maximum work extraction when τ ≥ 5τ B , while the extracted power is maximum near τ = τ B , implying the optimal operating time for the ratcheting process. In addition, we find that the average transport velocity is monotonically decreased as τ increases and present the upper bound for the velocity.

Migration of human plasmablast to the bone marrow is essential for the final differentiation of plasma cells and maintenance of effective humoral immunity. This migration is controlled by CXCL12/CXCR4-mediated activation of the protein kinase AKT. Herein, we show that the CXCL12-induced migration of human plasmablasts is dependent on glucose oxidation. Glucose depletion markedly inhibited plasmablast migration by 67%, and the glucose analog 2-deoxyglucose (2-DG) reduced the migration by 53%; conversely, glutamine depletion did not reduce the migration. CXCL12 boosted the oxygen consumption rate (OCR), and 2-DG treatment significantly reduced the levels of all measured tricarboxylic acid (TCA) cycle intermediates. AKT inhibitors blocked the CXCL12-mediated increase of OCR. CXCL12 enhanced the pyruvate dehydrogenase (PDH) activity by 13.5-fold in an AKT-dependent manner to promote mitochondrial oxidative phosphorylation. The knockdown and inhibition of PDH confirmed its indispensable role in CXCL12-induced migration. Cellular ATP levels fell by 91% upon exposure to 2-DG, and the mitochondrial ATP synthase inhibitor oligomycin inhibited CXCL12-induced migration by 85%. Low ATP levels inhibited the CXCL12-induced activation of AKT and phosphorylation of myosin light chains by 42%, which are required for cell migration. Thus, we have identified a mechanism that controls glucose oxidation via AKT signaling and PDH activation, which supports the migration of plasmablasts. This mechanism can provide insights into the proper development of long-lived plasma cells and is, therefore, essential for optimal humoral immunity. To our knowledge, this study is the first to investigate metabolic mechanisms underlying human plasmablast migration toward CXCL12.

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphomas (EBV + -DLBLs) tend to occur in immunocompromised patients, such as the elderly or those undergoing solid organ transplantation. The pathogenesis and genomic characteristics of EBV + -DLBLs are largely unknown because of the limited availability of human samples and lack of experimental animal models. We observed the development of 25 human EBV + -DLBLs during the engraftment of gastric adenocarcinomas into immunodeficient mice. An integrated genomic analysis of the human-derived EBV + -DLBLs revealed enrichment of mutations in Rho pathway genes, including RHPN2 , and Rho pathway transcriptomic activation. Targeting the Rho pathway using a Rho-associated protein kinase (ROCK) inhibitor, fasudil, markedly decreased tumor growth in EBV + -DLBL patient-derived xenograft (PDX) models. Thus, alterations in the Rho pathway appear to contribute to EBV-induced lymphomagenesis in immunosuppressed environments., (© 2018 by The American Society of Hematology.)

CD99 signaling is crucial to a diverse range of biological functions including survival and proliferation. CD99 engagement is reported to augment activator protein-1 (AP-1) activity through mitogen-activated protein (MAP) kinase pathways in a T-lymphoblastic lymphoma cell line Jurkat and in breast cancer cell lines. In this study, we report that CD99 differentially regulated AP-1 activity in the human myeloma cell line RPMI8226. CD99 was highly expressed and the CD99 engagement led to activation of the MAP kinases, but suppressed AP-1 activity by inducing the expression of basic leucine zipper transcription factor, ATF-like (BATF), a negative regulator of AP-1 in RPMI8226 cells. By contrast, engagement of CD99 enhanced AP-1 activity and did not change the BATF expression in Jurkat cells. CD99 engagement reduced the proliferation of RPMI8226 cells and expression of cyclin 1 and 3. Overall, these results suggest novel CD99 functions in RPMI8226 cells.

Migration of plasma cells to the bone marrow is critical factor to humoral immunity and controlled by chemokines. Regulator of G protein signaling 1 (RGS1) is a GTPase-activating protein that controls various crucial functions such as migration. Here, we show that RGS1 controls the chemotactic migration of RPMI 8226 human plasmacytoma cells and human plasmablasts. LPS strongly increased RGS1 expression and retarded the migration of RPMI 8226 cells by suppressing CXCL12-mediated AKT activation. RGS1 knockdown by siRNA abolished the retardation of migration and AKT suppression by LPS. RGS1-dependent regulation of migration via AKT is also observed in cultured plasmablasts. We propose novel functions of RGS1 that suppress AKT activation and the migration of RPMI 8226 cells and plasmablasts in CXCL12-mediated chemotaxis.

Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future.

We studied CdSe Quantum dot-Liposome Complexes (QLCs), which are GUVs (Giant Unilamellar Vesicles) incorporated with quantum dots (QDs) loaded into the DOPC lipid bilayer. QLCs were prepared by employing the electroswelling method combined with spin coating techniques. Hexadecylamine (HDA) coated CdSe QDs of five different sizes from blue- (radius ~2.05 nm) to red-emission (~3.5 nm) were used to examine what size of QDs can be loaded into the DOPC lipid bilayer. Blue (radius ~2.05 nm), green (~2.25 nm), and yellow (~2.65 nm)-emission QDs were successfully inserted in the lipid bilayer. However, we did not observe any QLCs for the orange-emission QDs (~3.0-3.15 nm) and red-emission ones (~3.5 nm). This QD size dependence of the incorporation into the lipid bilayer is partly supporting the predictions in our published theoretical work. DOPC lipids showed a much smaller QLC yield than that of asolectin which is a mixture of many different kinds of lipids. Our model explains this large difference in the population qualitatively. The existence of QDs in the lipid bilayer at a nanometer scale was confirmed by employing laser-scanning confocal microscopy, Cryo-TEM, and negative staining and sectioning TEM., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Linear polarizers and a half-wave plate are used to make a double slit whose width and center-to-center separation are continuously variable.