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In this work, intrinsic kinetics were decoupled from reactant diffusivities in the SC sunflower oil hydrogenation reaction on Pd/C using a steady-state diffusion and chemical reaction model under isothermal conditions in order to obtain low trans and stearic final products. A numerical solution combined with nonlinear parameter fitting was employed to solve this model. First, runs with small size of catalyst (0.4 mm) allowed to obtain kinetic constants irrespective of the diffusivity settings. Then, in a second set of runs, reactions were repeated on larger sizes of catalyst (up to 1 mm), that is, in the diffusion-limited regime. The results show that while hydrogen is transported by bulk pore diffusion, the oil seem to diffuse by surface diffusion. Diffusivity of H2 is about 10 times that of triglycerides. The overall diffusivity for triglycerides is about 10-8 m²/s, and changes 3 times with an increase in pressure, and 20 times with an increase in T. Linoleate selectivity (SLO) and specific isomerization (Si) also improve with decreasing the diffusion path. [ABSTRACT FROM AUTHOR]

Fluid-phase, continuous hydrogenations of sunflower oil on 2% Pd/C were carried out in an internal recycle, radial-flow, packed-bed microreactor (50 cm3) using propane as supercritical-fluid solvent. Temperature (428-488 K), oil liquid hourly space velocity (LHSV = 30-70), H2 mol composition (2-10%), and stirrer speed (52-262 rad/s) were changed according to a four-variable, two-level, central composite design to predict the effect of process variables on the iodine value (IV) and on trans fatty acid content (trans C18:1). Feed and product were well above the condensation conditions so that a single fluid phase was present (according to recent calculations by Pereda et al.). The total system pressure, the molar oil concentration and the catalyst mass were held constant at 20 MPa, 1 mol %, and 0.1085 g, respectively. An empirical quadratic-form response-surface model is shown to fit the results, and shows the regions where a potential CSTR process could be operated to obtain a certain outlet iodine value and a minimum trans C18:1 content. For the time-on stream values used here catalyst deactivation effects were not observed. In an extension of the results, a kinetic analysis of the steady-state CSTR reaction rate data allows determination of the kinetic constants, and their temperature dependency, for the multiple reactions of hydrogenation-isomerization network involving triglyceride species. The kinetic formalism, proposed earlier for vegetable oil hydrogenations, was used. [ABSTRACT FROM AUTHOR]

Abstract Background Different isoforms of VEGF-A (mainly VEGF121, VEGF165 and VEGF189) have been shown to display particular angiogenic properties in the generation of a functional tumor vasculature. Recently, a novel class of VEGF-A isoforms, designated as VEGFxxxb, generated through alternative splicing, have been described. Previous studies have suggested that these isoforms may inhibit angiogenesis. In the present work we have produced recombinant VEGF121/165b proteins in the yeast Pichia pastoris and constructed vectors to overexpress these isoforms and assess their angiogenic potential. Results Recombinant VEGF121/165b proteins generated either in yeasts or mammalian cells activated VEGFR2 and its downstream effector ERK1/2, although to a lesser extent than VEGF165. Furthermore, treatment of endothelial cells with VEGF121/165b increased cell proliferation compared to untreated cells, although such stimulation was lower than that induced by VEGF165. Moreover, in vivo angiogenesis assays confirmed angiogenesis stimulation by VEGF121/165b isoforms. A549 and PC-3 cells overexpressing VEGF121b or VEGF165b (or carrying the PCDNA3.1 empty vector, as control) and xenotransplanted into nude mice showed increased tumor volume and angiogenesis compared to controls. To assess whether the VEGFxxxb isoforms are differentially expressed in tumors compared to healthy tissues, immunohistochemical analysis was conducted on a breast cancer tissue microarray. A significant increase (p < 0.05) in both VEGFxxxb and total VEGF-A protein expression in infiltrating ductal carcinomas compared to normal breasts was observed. A positive significant correlation (r = 0.404, p = 0.033) between VEGFxxxb and total VEGF-A was found. Conclusions Our results demonstrate that VEGF121/165b are not anti-angiogenic, but weakly angiogenic isoforms of VEGF-A. In addition, VEGFxxxb isoforms are up-regulated in breast cancer in comparison with non malignant breast tissues. These results are to be taken into account when considering a possible use of VEGF121/165b-based therapies in patients.

Tumor recognition by T cells is essential for antitumor immunity. A comprehensive characterization of T cell diversity may be key to understanding the success of immunomodulatory drugs and failure of PD-1 blockade in tumors such as multiple myeloma (MM). Here, we use single-cell RNA and T cell receptor sequencing to characterize bone marrow T cells from healthy adults (n = 4) and patients with precursor (n = 8) and full-blown MM (n = 10). Large T cell clones from patients with MM expressed multiple immune checkpoints, suggesting a potentially dysfunctional phenotype. Dual targeting of PD-1 + LAG3 or PD-1 + TIGIT partially restored their function in mice with MM. We identify phenotypic hallmarks of large intratumoral T cell clones, and demonstrate that the CD27 - and CD27 + T cell ratio, measured by flow cytometry, may serve as a surrogate of clonal T cell expansions and an independent prognostic factor in 543 patients with MM treated with lenalidomide-based treatment combinations., (© 2023. Springer Nature Limited.)

The historical lack of preclinical models reflecting the genetic heterogeneity of multiple myeloma (MM) hampers the advance of therapeutic discoveries. To circumvent this limitation, we screened mice engineered to carry eight MM lesions (NF-κB, KRAS, MYC, TP53, BCL2, cyclin D1, MMSET/NSD2 and c-MAF) combinatorially activated in B lymphocytes following T cell-driven immunization. Fifteen genetically diverse models developed bone marrow (BM) tumors fulfilling MM pathogenesis. Integrative analyses of ∼500 mice and ∼1,000 patients revealed a common MAPK-MYC genetic pathway that accelerated time to progression from precursor states across genetically heterogeneous MM. MYC-dependent time to progression conditioned immune evasion mechanisms that remodeled the BM microenvironment differently. Rapid MYC-driven progressors exhibited a high number of activated/exhausted CD8 + T cells with reduced immunosuppressive regulatory T (T reg ) cells, while late MYC acquisition in slow progressors was associated with lower CD8 + T cell infiltration and more abundant T reg cells. Single-cell transcriptomics and functional assays defined a high ratio of CD8 + T cells versus T reg cells as a predictor of response to immune checkpoint blockade (ICB). In clinical series, high CD8 + T/T reg cell ratios underlie early progression in untreated smoldering MM, and correlated with early relapse in newly diagnosed patients with MM under Len/Dex therapy. In ICB-refractory MM models, increasing CD8 + T cell cytotoxicity or depleting T reg cells reversed immunotherapy resistance and yielded prolonged MM control. Our experimental models enable the correlation of MM genetic and immunological traits with preclinical therapy responses, which may inform the next-generation immunotherapy trials., (© 2023. The Author(s).)

Normal cell counterparts of solid and myeloid tumors accumulate mutations years before disease onset; whether this occurs in B lymphocytes before lymphoma remains uncertain. We sequenced multiple stages of the B lineage in elderly individuals and patients with lymphoplasmacytic lymphoma, a singular disease for studying lymphomagenesis because of the high prevalence of mutated MYD88 . We observed similar accumulation of random mutations in B lineages from both cohorts and unexpectedly found MYD88 L265P in normal precursor and mature B lymphocytes from patients with lymphoma. We uncovered genetic and transcriptional pathways driving malignant transformation and leveraged these to model lymphoplasmacytic lymphoma in mice, based on mutated MYD88 in B cell precursors and BCL2 overexpression. Thus, MYD88 L265P is a preneoplastic event, which challenges the current understanding of lymphomagenesis and may have implications for early detection of B cell lymphomas.

There is a paucity of adequate mouse models and cell lines available to study lung squamous cell carcinoma (LUSC). We have generated and characterized two models of phenotypically different transplantable LUSC cell lines, i.e. UN-SCC679 and UN-SCC680, derived from A/J mice that had been chemically induced with N-nitroso-tris-chloroethylurea (NTCU). Furthermore, we genetically characterized and compared both LUSC cell lines by performing whole-exome and RNA sequencing. These experiments revealed similar genetic and transcriptomic patterns that may correspond to the classic LUSC human subtype. In addition, we compared the immune landscape generated by both tumor cells lines in vivo and assessed their response to immune checkpoint inhibition. The differences between the two cell lines are a good model for the remarkable heterogeneity of human squamous cell carcinoma. Study of the metastatic potential of these models revealed that both cell lines represent the organotropism of LUSC in humans, i.e. affinity to the brain, bones, liver and adrenal glands. In summary, we have generated valuable cell line tools for LUSC research, which recapitulates the complexity of the human disease., Competing Interests: Competing interests R.K. is founder of PearlRiver Bio (now part of Centessa Pharmaceuticals), founder of NEO New Oncology (now part of Siemens Healthcare), and received consulting honoraria from PearlRiver Bio and NEO New Oncology. L.M.M. received a research grant from Astra-Zeneca and BMS, and is a licensed patent co-holder on Complement in LC early detection in AMADIX., (© 2022. Published by The Company of Biologists Ltd.)

For millions of years, endogenous retroelements have remained transcriptionally silent within mammalian genomes by epigenetic mechanisms. Modern anticancer therapies targeting the epigenetic machinery awaken retroelement expression, inducing antiviral responses that eliminate tumors through mechanisms not completely understood. Here, we find that massive binding of epigenetically activated retroelements by RIG-I and MDA5 viral sensors promotes ATP hydrolysis and depletes intracellular energy, driving tumor killing independently of immune signaling. Energy depletion boosts compensatory ATP production by switching glycolysis to mitochondrial oxidative phosphorylation, thereby reversing the Warburg effect. However, hyperfunctional succinate dehydrogenase in mitochondrial electron transport chain generates excessive oxidative stress that unleashes RIP1-mediated necroptosis. To maintain ATP generation, hyperactive mitochondrial membrane blocks intrinsic apoptosis by increasing BCL2 dependency. Accordingly, drugs targeting BCL2 family proteins and epigenetic inhibitors yield synergistic responses in multiple cancer types. Thus, epigenetic therapy kills cancer cells by rewiring mitochondrial metabolism upon retroelement activation, which primes mitochondria to apoptosis by BH3-mimetics. SIGNIFICANCE: The state of viral mimicry induced by epigenetic therapies in cancer cells remodels mitochondrial metabolism and drives caspase-independent tumor cell death, which sensitizes to BCL2 inhibitor drugs. This novel mechanism underlies clinical efficacy of hypomethylating agents and venetoclax in acute myeloid leukemia, suggesting similar combination therapies for other incurable cancers. This article is highlighted in the In This Issue feature, p. 995 ., (©2020 American Association for Cancer Research.)

Despite advances in chronic lymphocytic leukaemia (CLL) treatment, globally chemotherapy remains a central treatment modality, with chemotherapy trials representing an invaluable resource to explore disease-related/genetic features contributing to long-term outcomes. In 499 LRF CLL4 cases, a trial with >12 years follow-up, we employed targeted resequencing of 22 genes, identifying 623 mutations. After background mutation rate correction, 11/22 genes were recurrently mutated at frequencies between 3.6% (NFKBIE) and 24% (SF3B1). Mutations beyond Sanger resolution (<12% VAF) were observed in all genes, with KRAS mutations principally composed of these low VAF variants. Firstly, employing orthogonal approaches to confirm <12% VAF TP53 mutations, we assessed the clinical impact of TP53 clonal architecture. Whilst ≥ 12% VAF TP53mut cases were associated with reduced PFS and OS, we could not demonstrate a difference between <12% VAF TP53 mutations and either wild type or ≥12% VAF TP53mut cases. Secondly, we identified biallelic BIRC3 lesions (mutation and deletion) as an independent marker of inferior PFS and OS. Finally, we observed that mutated MAPK-ERK genes were independent markers of poor OS in multivariate survival analysis. In conclusion, our study supports using targeted resequencing of expanded gene panels to elucidate the prognostic impact of gene mutations.

Chronic lymphocytic leukemia patients with mutated immunoglobulin heavy-chain genes (IGHV-M), particularly those lacking poor-risk genomic lesions, often respond well to chemoimmunotherapy (CIT). DNA methylation profiling can subdivide early-stage patients into naive B-cell-like CLL (n-CLL), memory B-cell-like CLL (m-CLL), and intermediate CLL (i-CLL), with differing times to first treatment and overall survival. However, whether DNA methylation can identify patients destined to respond favorably to CIT has not been ascertained. We classified treatment-naive patients (n = 605) from 3 UK chemo and CIT clinical trials into the 3 epigenetic subgroups, using pyrosequencing and microarray analysis, and performed expansive survival analysis. The n-CLL, i-CLL, and m-CLL signatures were found in 80% (n = 245/305), 17% (53/305), and 2% (7/305) of IGHV-unmutated (IGHV-U) cases, respectively, and in 9%, (19/216), 50% (108/216), and 41% (89/216) of IGHV-M cases, respectively. Multivariate Cox proportional analysis identified m-CLL as an independent prognostic factor for overall survival (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.24-0.87; P = .018) in CLL4, and for progression-free survival (HR, 0.25; 95% CI, 0.10-0.57; P = .002) in ARCTIC and ADMIRE patients. The analysis of epigenetic subgroups in patients entered into 3 first-line UK CLL trials identifies m-CLL as an independent marker of prolonged survival and may aid in the identification of patients destined to demonstrate prolonged survival after CIT., (© 2019 by The American Society of Hematology.)

Chronic lymphocytic leukemia (CLL) patients with differential somatic hypermutation status of the immunoglobulin heavy variable genes, namely mutated or unmutated, display fundamental clinico-biological differences. Considering this, we assessed prognosis separately within mutated (M-CLL) and unmutated (U-CLL) CLL in 3015 patients, hypothesizing that the relative significance of relevant indicators may differ between these two categories. Within Binet A M-CLL patients, besides TP53 abnormalities, trisomy 12 and stereotyped subset #2 membership were equivalently associated with the shortest time-to-first-treatment and a treatment probability at five and ten years after diagnosis of 40% and 55%, respectively; the remaining cases exhibited 5-year and 10-year treatment probability of 12% and 25%, respectively. Within Binet A U-CLL patients, besides TP53 abnormalities, del(11q) and/or SF3B1 mutations were associated with the shortest time-to-first-treatment (5- and 10-year treatment probability: 78% and 98%, respectively); in the remaining cases, males had a significantly worse prognosis than females. In conclusion, the relative weight of indicators that can accurately risk stratify early-stage CLL patients differs depending on the somatic hypermutation status of the immunoglobulin heavy variable genes of each patient. This finding highlights the fact that compartmentalized approaches based on immunogenetic features are necessary to refine and tailor prognostication in CLL., (Copyright © 2019 Ferrata Storti Foundation.)

The increased risk of Richter transformation (RT) in patients with chronic lymphocytic leukaemia (CLL) due to Epstein-Barr virus (EBV) reactivation during immunosuppressive therapy with fludarabine other targeted agents remains controversial. Among 31 RT cases classified as diffuse large B-cell lymphoma (DLBCL), seven (23%) showed EBV expression. In contrast to EBV - tumours, EBV + DLBCLs derived predominantly from IGVH-hypermutated CLL, and they also showed CLL-unrelated IGVH sequences more frequently. Intriguingly, despite having different cellular origins, clonally related and unrelated EBV + DLBCLs shared a previous history of immunosuppressive chemo-immunotherapy, a non-germinal centre DLBCL phenotype, EBV latency programme type II or III, and very short survival. These data suggested that EBV reactivation during therapy-related immunosuppression can transform either CLL cells or non-tumoural B lymphocytes into EBV + DLBCL. To investigate this hypothesis, xenogeneic transplantation of blood cells from 31 patients with CLL and monoclonal B-cell lymphocytosis (MBL) was performed in Rag2 -/- IL2γc -/- mice. Remarkably, the recipients' impaired immunosurveillance favoured the spontaneous outgrowth of EBV + B-cell clones from 95% of CLL and 64% of MBL patients samples, but not from healthy donors. Eventually, these cells generated monoclonal tumours (mostly CLL-unrelated but also CLL-related), recapitulating the principal features of EBV + DLBCL in patients. Accordingly, clonally related and unrelated EBV + DLBCL xenografts showed indistinguishable cellular, virological and molecular features, and synergistically responded to combined inhibition of EBV replication with ganciclovir and B-cell receptor signalling with ibrutinib in vivo. Our study underscores the risk of RT driven by EBV in CLL patients receiving immunosuppressive therapies, and provides the scientific rationale for testing ganciclovir and ibrutinib in EBV + DLBCL. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd., (Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)

Chronic lymphocytic leukemia (CLL) is a heterogeneous B-cell cancer exhibiting a wide spectrum of disease courses and treatment responses. Molecular characterization of RNA and DNA from CLL cases has led to the identification of important driver mutations and disease subtypes, but the precise mechanisms of disease progression remain elusive. To further our understanding of CLL biology we performed isobaric labeling and mass spectrometry proteomics on 14 CLL samples, comparing them with B-cells from healthy donors (HDB). Of 8694 identified proteins, ∼6000 were relatively quantitated between all samples (q<0.01). A clear CLL signature, independent of subtype, of 544 significantly overexpressed proteins relative to HDB was identified, highlighting established hallmarks of CLL ( e.g. CD5, BCL2, ROR1 and CD23 overexpression). Previously unrecognized surface markers demonstrated overexpression ( e.g. CKAP4, PIGR, TMCC3 and CD75) and three of these (LAX1, CLEC17A and ATP2B4) were implicated in B-cell receptor signaling, which plays an important role in CLL pathogenesis. Several other proteins ( e.g. Wee1, HMOX1/2, HDAC7 and INPP5F) were identified with significant overexpression that also represent potential targets. Western blotting confirmed overexpression of a selection of these proteins in an independent cohort. mRNA processing machinery were broadly upregulated across the CLL samples. Spliceosome components demonstrated consistent overexpression ( p = 1.3 × 10 -21 ) suggesting dysregulation in CLL, independent of SF3B1 mutations. This study highlights the potential of proteomics in the identification of putative CLL therapeutic targets and reveals a subtype-independent protein expression signature in CLL., Competing Interests: Conflict of Interest Disclosure: M.S.C. is a retained consultant for Bioinvent and has performed educational and advisory roles for Baxalta. He has received research funding from Roche, Gilead and GSK. A.J.S. is a consultant and has also received research funding and honoraria from Portola Pharmaceuticals (USA) and Gilead (UK)., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)

Purpose: B-cell receptor (BCR)-associated kinase inhibitors, such as ibrutinib, have revolutionized the treatment of chronic lymphocytic leukemia (CLL). However, these agents are not curative, and resistance is already emerging in a proportion of patients. IL4, expressed in CLL lymph nodes, can augment BCR signaling and reduce the effectiveness of BCR kinase inhibitors. Therefore, simultaneous targeting of the IL4- and BCR signaling pathways by cerdulatinib, a novel dual Syk/JAK inhibitor currently in clinical trials (NCT01994382), may improve treatment responses in patients. Experimental Design: PBMCs from patients with CLL were treated in vitro with cerdulatinib alone or in combination with venetoclax. Cell death, chemokine, and cell signaling assay were performed and analyzed by flow cytometry, immunoblotting, q-PCR, and ELISA as indicated. Results: At concentrations achievable in patients, cerdulatinib inhibited BCR- and IL4-induced downstream signaling in CLL cells using multiple readouts and prevented anti-IgM- and nurse-like cell (NLC)-mediated CCL3/CCL4 production. Cerdulatinib induced apoptosis of CLL cells, in a time- and concentration-dependent manner, and particularly in IGHV-unmutated samples with greater BCR signaling capacity and response to IL4, or samples expressing higher levels of sIgM, CD49d + , or ZAP70 + Cerdulatinib overcame anti-IgM, IL4/CD40L, or NLC-mediated protection by preventing upregulation of MCL-1 and BCL-X L ; however, BCL-2 expression was unaffected. Furthermore, in samples treated with IL4/CD40L, cerdulatinib synergized with venetoclax in vitro to induce greater apoptosis than either drug alone. Conclusions: Cerdulatinib is a promising therapeutic for the treatment of CLL either alone or in combination with venetoclax, with the potential to target critical survival pathways in this currently incurable disease. Clin Cancer Res; 23(9); 2313-24. ©2016 AACR ., (©2016 American Association for Cancer Research.)

Histone methyltransferases (HMTs) are important epigenetic regulators of gene transcription and are disrupted at the genomic level in a spectrum of human tumours including haematological malignancies. Using high-resolution single nucleotide polymorphism (SNP) arrays, we identified recurrent deletions of the SETD2 locus in 3% (8/261) of chronic lymphocytic leukaemia (CLL) patients. Further validation in two independent cohorts showed that SETD2 deletions were associated with loss of TP53, genomic complexity and chromothripsis. With next-generation sequencing we detected mutations of SETD2 in an additional 3.8% of patients (23/602). In most cases, SETD2 deletions or mutations were often observed as a clonal event and always as a mono-allelic lesion, leading to reduced mRNA expression in SETD2-disrupted cases. Patients with SETD2 abnormalities and wild-type TP53 and ATM from five clinical trials employing chemotherapy or chemo-immunotherapy had reduced progression-free and overall survival compared with cases wild type for all three genes. Consistent with its postulated role as a tumour suppressor, our data highlight SETD2 aberration as a recurrent, early loss-of-function event in CLL pathobiology linked to aggressive disease., Competing Interests: The authors state that that there are no conflicts of interests.

Chronic lymphocytic leukemia (CLL) with unmutated (U-CLL) or mutated (M-CLL) immunoglobulin gene heavy-chain variable region (IGHV) displays different states of anergy, indicated by reduced surface immunoglobulin M (sIgM) levels and signaling, consequent to chronic (super)antigen exposure. The subsets also differ in the incidence of high-risk genetic aberrations and in DNA methylation profile, preserved from the maturational status of the original cell. We focused on sIgM expression and function, measured as intracellular Ca(2+) mobilization following stimulation, and probed correlations with clinical outcome. The relationship with genetic features and maturation status defined by DNA methylation of an 18-gene panel signature was then investigated. sIgM levels/signaling were higher and less variable in U-CLL than in M-CLL and correlated with disease progression between and within U-CLL and M-CLL. In U-CLL, increased levels/signaling associated with +12, del(17p) or NOTCH1 mutations. In M-CLL, there were fewer genetic lesions, although the methylation maturation status, generally higher than in U-CLL, varied and was increased in cases with lower sIgM levels/signaling. These features revealed heterogeneity in M-CLL and U-CLL with clear clinical correlations. Multivariate analyses with phenotype, genetic lesions, or DNA methylation maturation status identified high sIgM levels as a new potential independent factor for disease progression. Multiple influences on sIgM include the cell of origin, the clonal history of antigen encounter in vivo, and genetic damage. This simple marker compiles these different factors into an indicator worthy of further investigations for prediction of clinical behavior, particularly within the heterogeneous M-CLL subset., (© 2016 by The American Society of Hematology.)

We report on markedly different frequencies of genetic lesions within subsets of chronic lymphocytic leukemia patients carrying mutated or unmutated stereotyped B-cell receptor immunoglobulins in the largest cohort (n=565) studied for this purpose. By combining data on recurrent gene mutations (BIRC3, MYD88, NOTCH1, SF3B1 and TP53) and cytogenetic aberrations, we reveal a subset-biased acquisition of gene mutations. More specifically, the frequency of NOTCH1 mutations was found to be enriched in subsets expressing unmutated immunoglobulin genes, i.e. #1, #6, #8 and #59 (22-34%), often in association with trisomy 12, and was significantly different (P<0.001) to the frequency observed in subset #2 (4%, aggressive disease, variable somatic hypermutation status) and subset #4 (1%, indolent disease, mutated immunoglobulin genes). Interestingly, subsets harboring a high frequency of NOTCH1 mutations were found to carry few (if any) SF3B1 mutations. This starkly contrasts with subsets #2 and #3 where, despite their immunogenetic differences, SF3B1 mutations occurred in 45% and 46% of cases, respectively. In addition, mutations within TP53, whilst enriched in subset #1 (16%), were rare in subsets #2 and #8 (both 2%), despite all being clinically aggressive. All subsets were negative for MYD88 mutations, whereas BIRC3 mutations were infrequent. Collectively, this striking bias and skewed distribution of mutations and cytogenetic aberrations within specific chronic lymphocytic leukemia subsets implies that the mechanisms underlying clinical aggressiveness are not uniform, but rather support the existence of distinct genetic pathways of clonal evolution governed by a particular stereotyped B-cell receptor selecting a certain molecular lesion(s)., (Copyright© Ferrata Storti Foundation.)

Kinase inhibitors targeting the B-cell receptor (BCR) are now prominent in the treatment of chronic lymphocytic leukemia (CLL). We have focused here on interleukin 4 (IL-4), a cytokine that protects normal and malignant B cells from apoptosis and increases surface immunoglobulin M (sIgM) expression on murine splenic B cells. First, we have demonstrated that IL-4 treatment increased sIgM expression in vitro on peripheral blood B cells obtained from healthy individuals. In CLL, IL-4 target genes are overexpressed in cells purified from the lymph nodes of patients compared with cells derived from matched blood and bone marrow samples. As for normal B cells, IL-4 increased sIgM expression on CLL cells in vitro, especially in samples expressing unmutated V-genes. IL-4-induced sIgM expression was associated with increased receptor signalling activity, measured by anti-IgM-induced calcium mobilization, and with increased expression of CD79B messenger RNA and protein, and the "mature" glycoform of sIgM. Importantly, the ability of the BCR-associated kinase inhibitors idelalisib and ibrutinib, approved for treatment of CLL and other B-cell malignancies, to inhibit anti-IgM-induced signalling was reduced following IL-4 pretreatment in samples from the majority of patients. In contrast to stimulatory effects on sIgM, IL-4 decreased CXCR4 and CXCR5 expression; therefore, CLL cells, particularly within the progressive unmutated V-gene subset, may harness the ability of IL-4 to promote BCR signalling and B-cell retention within lymph nodes. Effects of IL-4 were mediated via JAK3/STAT6 and we propose a potential role for JAK inhibitors in combination with BCR kinase inhibitors for the treatment of CLL., (© 2016 by The American Society of Hematology.)

Introduction: Anti-programmed cell death 1 (anti-PD-1) and anti-programmed cell death ligand 1 (PD-L1) antagonist monoclonal antibodies (mAbs) against metastatic non-small cell lung cancer with special efficacy in patients with squamous cell lung cancer are being developed in the clinic. However, robust and reliable experimental models to test immunotherapeutic combinations in squamous lung tumors are still lacking., Methods: We generated a transplantable squamous cell carcinoma cell line (UN-SCC680AJ) from a lung tumor induced by chronic N-nitroso-tris-chloroethylurea mutagenesis in A/J mice. Tumor cells expressed cytokeratins, overexpressed p40, and lacked thyroid transcription factor 1, confirming the squamous lineage reported by histological analysis. More than 200 mutations found in its exome suggested potential for antigenicity. Immunocompetent mice subcutaneously implanted with this syngeneic cell line were treated with anti-CD137 and/or anti-PD-1 mAbs and monitored for tumor growth/progression or assessed for intratumoral leukocyte infiltration using immunohistochemical analysis and flow cytometry., Results: In syngeneic mice, large 12-day-established tumors derived from the transplantable cell line variant UN-SCC680AJ were amenable to curative treatment with anti-PD-1, anti-PD-L1, or anti-CD137 immunostimulatory mAbs. Single-agent therapies lost curative efficacy when treatment was started beyond day +17, whereas a combination of anti-PD-1 plus anti-CD137 achieved complete rejections. Tumor cells expressed weak baseline PD-L1 on the plasma membrane, but this could be readily induced by interferon-γ. Combined treatment efficacy required CD8 T cells and induced a leukocyte infiltrate in which T lymphocytes co-expressing CD137 and PD-1 were prominent., Conclusions: These promising results advocate the use of combined anti-PD-1/PD-L1 plus anti-CD137 mAb immunotherapy for the treatment of squamous non-small cell lung cancer in the clinical setting., (Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.)

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic disorder with heterogeneous clinical, morphological and genetic characteristics. Clonal cytogenetic abnormalities are found in 20-30% of patients with CMML. Patients with low risk cytogenetic features (normal karyotype and isolated loss of Y chromosome) account for ∼80% of CMML patients and often fall into the low risk categories of CMML prognostic scores. We hypothesized that single nucleotide polymorphism arrays (SNP-A) karyotyping could detect cryptic chromosomal alterations with prognostic impact in these subgroup of patients. SNP-A were performed at diagnosis in 128 CMML patients with low risk karyotypes or uninformative results for conventional G-banding cytogenetics (CC). Copy number alterations (CNAs) and regions of copy number neutral loss of heterozygosity (CNN-LOH) were detected in 67% of patients. Recurrent CNAs included gains in regions 8p12 and 21q22 as well as losses in 10q21.1 and 12p13.2. Interstitial CNN-LOHs were recurrently detected in the following regions: 4q24-4q35, 7q32.1-7q36.3, and 11q13.3-11q25. Statistical analysis showed that some of the alterations detected by SNP-A associated with the patients' outcome. A shortened overall survival (OS) and progression free survival (PFS) was observed in cases where the affected size of the genome (considering CNAs and CNN-LOHs) was >11 Mb. In addition, presence of interstitial CNN-LOH was predictive of poor OS. Presence of CNAs (≥1) associated with poorer OS and PFS in the patients with myeloproliferative CMML. Overall, SNP-A analysis increased the diagnostic yield in patients with low risk cytogenetic features or uninformative CC and added prognostic value to this subset of patients., (© 2015 Wiley Periodicals, Inc.)

Current treatment strategies for chronic lymphocytic leukemia (CLL) involve a combination of conventional chemotherapeutics, monoclonal antibodies, and targeted signaling inhibitors. However, CLL remains largely incurable, with drug resistance and treatment relapse a common occurrence, leading to the search for novel treatments. Mechanistic target of rapamycin (mTOR)-specific inhibitors have been previously assessed but their efficacy is limited due to a positive feedback loop via mTOR complex 2 (mTORC2), resulting in activation of prosurvival signaling. In this study, we show that the dual phosphatidylinositol 3-kinase (PI3K)/mTOR inhibitor PF-04691502 does not induce an mTORC2 positive feedback loop similar to other PI3K inhibitors but does induce substantial antitumor effects. PF-04691502 significantly reduced survival coincident with the induction of Noxa and Puma, independently of immunoglobulin heavy chain variable region mutational status, CD38, and ZAP-70 expression. PF-04691502 inhibited both anti-immunoglobulin M-induced signaling and overcame stroma-induced survival signals and migratory stimuli from CXCL12. Equivalent in vitro activity was seen in the Eμ-TCL1 murine model of CLL. In vivo, PF-04691502 treatment of tumor-bearing animals resulted in a transient lymphocytosis, followed by a clear reduction in tumor in the blood, bone marrow, spleen, and lymph nodes. These data indicate that PF-04691502 or other dual PI3K/mTOR inhibitors in development may prove efficacious for the treatment of CLL, increasing our armamentarium to successfully manage this disease., (© 2015 by The American Society of Hematology.)

Unlabelled: The TNF receptor-associated protein 1 (TRAP1) is a mitochondrial HSP that has been related to drug resistance and protection from apoptosis in colorectal and prostate cancer. Here, the effect of TRAP1 ablation on cell proliferation, survival, apoptosis, and mitochondrial function was determined in non-small cell lung cancer (NSCLC). In addition, the prognostic value of TRAP1 was evaluated in patients with NSCLC. These results demonstrate that TRAP1 knockdown reduces cell growth and clonogenic cell survival. Moreover, TRAP1 downregulation impairs mitochondrial functions such as ATP production and mitochondrial membrane potential as measured by TMRM (tetramethylrhodamine methylester) uptake, but it does not affect mitochondrial density or mitochondrial morphology. The effect of TRAP1 silencing on apoptosis, analyzed by flow cytometry and immunoblot expression (cleaved PARP, caspase-9, and caspase-3) was cell line and context dependent. Finally, the prognostic potential of TRAP1 expression in NSCLC was ascertained via immunohistochemical analysis which revealed that high TRAP1 expression was associated with increased risk of disease recurrence (univariate analysis, P = 0.008; multivariate analysis, HR: 2.554; 95% confidence interval, 1.085-6.012; P = 0.03). In conclusion, these results demonstrate that TRAP1 impacts the viability of NSCLC cells, and that its expression is prognostic in NSCLC., Implications: TRAP1 controls NSCLC proliferation, apoptosis, and mitochondrial function, and its status has prognostic potential in NSCLC., Competing Interests: of potential conflicts of interest: No potential conflicts of interest are disclosed, (©2014 AACR.)

The vascular endothelial growth factor (VEGF) pathway is a clinically validated antiangiogenic target for non-small cell lung cancer (NSCLC). However, some contradictory results have been reported on the biological effects of antiangiogenic drugs. In order to evaluate the efficacy of these drugs in NSCLC histological subtypes, we analyzed the anticancer effect of two anti-VEGFR2 therapies (sunitinib and DC101) in chemically induced mouse models and tumorgrafts of lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Antiangiogenic treatments induced vascular trimming in both histological subtypes. In ADC tumors, vascular trimming was accompanied by tumor stabilization. In contrast, in SCC tumors, antiangiogenic therapy was associated with disease progression and induction of tumor proliferation. Moreover, in SCC, anti-VEGFR2 therapies increased the expression of stem cell markers such as aldehyde dehydrogenase 1A1, CD133, and CD15, independently of intratumoral hypoxia. In vitro studies with ADC cell lines revealed that antiangiogenic treatments reduced pAKT and pERK signaling and inhibited proliferation, while in SCC-derived cell lines the same treatments increased pAKT and pERK, and induced survival. In conclusion, this study evaluates for the first time the effect of antiangiogenic drugs in lung SCC murine models in vivo and sheds light on the contradictory results of antiangiogenic therapies in NSCLC.

Purpose: Antiangiogenic therapies targeting the vascular endothelial growth factor (VEGF) pathway have yielded more modest clinical benefit to patients with non-small-cell lung cancer (NSCLC) than initially expected. Clinical data suggest a distinct biologic role of the VEGF pathway in the different histologic subtypes of lung cancer. To clarify the influence of histologic differentiation in the prognostic relevance of VEGF-mediated signaling in NSCLC, we performed a concomitant analysis of the expression of three key elements of the VEGF pathway in the earliest stages of the following two principal histologic subtypes: squamous cell carcinoma (SCC) and adenocarcinoma (ADC)., Patients and Methods: We evaluated tumor cell expression of VEGF, VEGF receptor (VEGFR) 1, and VEGFR2 using automatic immunostaining in a series of 298 patients with early-stage NSCLC recruited as part of the multicenter European Early Lung Cancer Detection Group project. A score measuring the VEGF signaling pathway was calculated by adding the tumor cell expression value of VEGF and its two receptors. The results were validated in two additional independent cohorts of patients with NSCLC., Results: The combination of high VEGF, VEGFR1, and VEGFR2 protein expression was associated with lower risk of disease progression in early SCC (univariate analysis, P = .008; multivariate analysis, hazard ratio, 0.62; 95% CI, 0.42 to 0.92; P = .02). The results were validated in two independent patient cohorts, confirming the favorable prognostic value of high VEGF signaling score in early lung SCC., Conclusion: Our results clearly indicate that the combination of high expression of the three key elements in the VEGF pathway is associated with a good prognosis in patients with early SCC but not in patients with ADC.

Background: Different isoforms of VEGF-A (mainly VEGF₁₂₁, VEGF₁₆₅ and VEGF189) have been shown to display particular angiogenic properties in the generation of a functional tumor vasculature. Recently, a novel class of VEGF-A isoforms, designated as VEGF(xxx)b, generated through alternative splicing, have been described. Previous studies have suggested that these isoforms may inhibit angiogenesis. In the present work we have produced recombinant VEGF₁₂₁/₁₆₅b proteins in the yeast Pichia pastoris and constructed vectors to overexpress these isoforms and assess their angiogenic potential., Results: Recombinant VEGF₁₂₁/₁₆₅b proteins generated either in yeasts or mammalian cells activated VEGFR2 and its downstream effector ERK1/2, although to a lesser extent than VEGF₁₆₅. Furthermore, treatment of endothelial cells with VEGF₁₂₁/₁₆₅b increased cell proliferation compared to untreated cells, although such stimulation was lower than that induced by VEGF₁₆₅. Moreover, in vivo angiogenesis assays confirmed angiogenesis stimulation by VEGF₁₂₁/₁₆₅b isoforms. A549 and PC-3 cells overexpressing VEGF₁₂₁b or VEGF₁₆₅b (or carrying the PCDNA3.1 empty vector, as control) and xenotransplanted into nude mice showed increased tumor volume and angiogenesis compared to controls. To assess whether the VEGF(xxx)b isoforms are differentially expressed in tumors compared to healthy tissues, immunohistochemical analysis was conducted on a breast cancer tissue microarray. A significant increase (p < 0.05) in both VEGF(xxx)b and total VEGF-A protein expression in infiltrating ductal carcinomas compared to normal breasts was observed. A positive significant correlation (r = 0.404, p = 0.033) between VEGF(xxx)b and total VEGF-A was found., Conclusions: Our results demonstrate that VEGF₁₂₁/₁₆₅b are not anti-angiogenic, but weakly angiogenic isoforms of VEGF-A. In addition, VEGF(xxx)b isoforms are up-regulated in breast cancer in comparison with non malignant breast tissues. These results are to be taken into account when considering a possible use of VEGF₁₂₁/₁₆₅b-based therapies in patients.

Background and Objectives: The presence of specific chromosomal translocations in acute lymphoblastic leukemias (ALL) plays an important role in determining the prognosis of the patients. Our aim is to develop a highly sensitive and specific method to screen simultaneously for the four most frequent translocations in ALL: t(9;22), t(1;19), t(4;11), t(12;21)., Design and Methods: Our approach uses a multiplex-polymerase chain reaction (PCR) method, which involves two rounds of PCR using fluorescence-labeled nested primers. The chimeric transcripts resulting from these translocations can be identified by agarose gel electrophoresis or by fluorescence analysis. To validate this method we carried out the analysis in 42 pediatric ALL samples previously studied by cytogenetic and fluorescent in situ hybridization (FISH) techniques., Results: In all samples with a known translocation detected by cytogenetic or FISH techniques, the same translocation was identified by the multiplex-PCR assay. Moreover, with this method we detected rearrangements in five patients in clinical remission and in two patients at diagnosis for whom karyotypes were normal and rearrangements had not been detected. The application of this multiplex-PCR assay was also useful in cases without cytogenetic results., Interpretation and Conclusions: These results show that the multiplex-PCR method allows reliable, sensitive and rapid detection of the prognostically significant translocations in ALL. We believe that this assay combined with cytogenetic analysis should be the strategy of choice for the initial diagnostic phase of acute lymphoblastic leukemia, and that it could be used not only at diagnosis but also to follow-up these alterations in remission samples without previous controls.

An unusual cytogenetic rearrangement, described as ins(22;9)(q11;q34q21), was detected in a 49-year-old male patient diagnosed with chronic myeloid leukemia (CML). Reverse transcriptase polymerase chain reaction (RT-PCR) revealed a b3a2 fusion transcript. In order to confirm the cytogenetic findings and fully characterize the inverted insertion, we performed fluorescence in situ hybridization (FISH) assays using locus-specific and whole chromosome painting probes. Our FISH analysis showed the presence of the BCR/ABL fusion gene, verified the insertion and determined that the breakpoint on chromosome 22 where the insertion took place was located proximal to the BCR gene and distal to the TUPLE1 gene on 22q11.