Microenvironmental interactions between endothelial and lymphoma cells: a role for the canonical WNT pathway in Hodgkin lymphoma.

The interaction between vascular endothelial cells (ECs) and cancer cells is of vital importance to understand tumor dissemination. A paradigmatic cancer to study cell-cell interactions is classical Hodgkin Lymphoma (cHL) owing to its complex microenvironment. The role of the interplay between cHL and ECs remains poorly understood. Here we identify canonical WNT pathway activity as important for the mutual interactions between cHL cells and ECs. We demonstrate that local canonical WNT signaling activates cHL cell chemotaxis toward ECs, adhesion to EC layers and cell invasion using not only the Wnt-inhibitor Dickkopf, tankyrases and casein kinase 1 inhibitors but also knockdown of the lymphocyte enhancer binding-factor 1 (LEF-1) and ß-catenin in cHL cells. Furthermore, LEF-1- and ß-catenin-regulated cHL secretome promoted EC migration, sprouting and vascular tube formation involving vascular endothelial growth factor A (VEGF-A). Importantly, high VEGFA expression is associated with a worse overall survival of cHL patients. These findings strongly support the concept that WNTs might function as a regulator of lymphoma dissemination by affecting cHL cell chemotaxis and promoting EC behavior and thus angiogenesis through paracrine interactions.

WNT5A: a motility-promoting factor in Hodgkin lymphoma.

Classical Hodgkin lymphoma (cHL) has a typical clinical manifestation, with dissemination involving functionally neighboring lymph nodes. The factors involved in the spread of lymphoma cells are poorly understood. Here we show that cHL cell lines migrate with higher rates compared with non-Hodgkin lymphoma cell lines. cHL cell migration, invasion and adhesion depend on autocrine WNT signaling as revealed by the inhibition of WNT secretion with the porcupine inhibitors Wnt-C59/IWP-2, but did not affect cell proliferation. While application of recombinant WNT5A or WNT5A overexpression stimulates HL cell migration, neither WNT10A, WNT10B nor WNT16 did so. Time-lapse studies revealed an amoeboid type of cell migration modulated by WNT5A. Reduced migration distances and velocity of cHL cells, as well as altered movement patterns, were observed using porcupine inhibitor or WNT5A antagonist. Knockdown of Frizzled5 and Dishevelled3 disrupted the WNT5A-mediated RHOA activation and cell migration. Overexpression of DVL3-K435M or inhibition of ROCK (Rho-associated protein kinase) by Y-27632/H1152P disrupted cHL cell migration. In addition to these mechanistic insights into the role of WNT5A in vitro, global gene expression data revealed an increased WNT5A expression in primary HL cells in comparison with normal B-cell subsets and other lymphomas. Furthermore, the activity of both porcupine and WNT5A in cHL cells had an impact on lymphoma development in the chick chorionallantoic membrane assay. Massive bleeding of these lymphomas was significantly reduced after inhibition of WNT secretion by Wnt-C59. Therefore, a model is proposed where WNT signaling has an important role in regulating tumor-promoting processes.

Physical Activity and Exercise Interventions in the Workplace Impacting Work Outcomes: A Stakeholder-Centered Best Evidence Synthesis of Systematic Reviews.

BACKGROUND: The prevention of work disability is beneficial to employees and employers, and mitigates unnecessary societal costs associated with social welfare. Many service providers and employers have initiated workplace interventions designed to reduce unnecessary work disability. OBJECTIVE: To conduct a best-evidence synthesis of systematic reviews on workplace interventions that address physical activities or exercise and their impact on workplace absence, work productivity or financial outcomes. METHODS: Using a participatory research approach, academics and stakeholders identified inclusion and exclusion criteria, built an abstraction table, evaluated systematic review quality and relevance, and interpreted the combined findings. A minimum of two scientists participated in a methodological review of the literature followed by a consensus process. RESULTS: Stakeholders and researchers participated as a collaborative team. 3363 unique records were identified, 115 full text articles and 46 systematic reviews were included, 18 assessed the impact of physical fitness or exercise interventions. 11 focused on general workers rather than workers who were absent from work at baseline; 16 of the reviews assessed work absence, 4 assessed productivity and 6 assessed financial impacts. CONCLUSION: The strongest evidence supports the use of short, simple exercise or fitness programs for both workers at work and those absent from work at baseline. For workers at work, simple exercise programs (1-2 modal components) appear to provide similar benefits to those using more complex multimodal interventions. For workers off-work with subacute low back pain, there is evidence that some complex exercise programs may be more effective than simple exercise interventions, especially if they involve workplace stakeholder engagement, communication and coordination with employers and other stakeholders. The development and utilization of standardized definitions, methods and measures and blinded evaluation would improve research quality and strengthen stakeholder-centered guidance.

Mental Health Interventions in the Workplace and Work Outcomes: A Best-Evidence Synthesis of Systematic Reviews.

BACKGROUND: Mental health issues in the workplace are a growing concern among organizations and policymakers, but it remains unclear what interventions are effective in preventing mental health problems and their associated organizational consequences. This synthesis reports on workplace mental health interventions that impact absenteeism, productivity and financial outcomes. OBJECTIVE: To determine the level of evidence supporting mental health interventions as valuable to work outcomes. METHODS: Databases were searched for systematic reviews between 2000 and 2012: Medline, EMBASE, the Cochrane Database of Systematic Reviews, DARE, CINAHL, PsycINFO and TRIP. Grey literature searches included health-evidence.ca, Rehab+, National Rehabilitation Information Center (NARIC), and Institute for Work and Health. The assessment of articles for inclusion criteria and methodological quality was conducted independently by two or more researchers, with differences resolved through consensus. RESULTS: The search resulted in 3363 titles, of which 3248 were excluded following title/abstract review, with 115 articles retrieved for full-text review. 14 articles finally met the inclusion criteria and are summarized in this synthesis. CONCLUSION: There is moderate evidence for the effectiveness of workplace mental health interventions on improved workplace outcomes. Certain types of programs, such as those incorporating both mental and physical health interventions, multicomponent mental health and/or psychosocial interventions, and exposure in vivo containing interventions for particular anxiety disorders had a greater level of research evidence to support their effectiveness.

Social Support and Supervisory Quality Interventions in the Workplace: A Stakeholder-Centered Best-Evidence Synthesis of Systematic Reviews on Work Outcomes.

BACKGROUND: There is controversy surrounding the impact of workplace interventions aimed at improving social support and supervisory quality on absenteeism, productivity and financial outcomes. OBJECTIVE: To determine the value of social support interventions for work outcomes. METHODS: Databases were searched for systematic reviews between 2000 and 2012 to complete a synthesis of systematic reviews guided by the PRISMA statement and the IOM guidelines for systematic reviews. Assessment of articles for inclusion and methodological quality was conducted independently by at least two researchers, with differences resolved by consensus. RESULTS: The search resulted in 3363 titles of which 3248 were excluded following title/abstract review, leaving 115 articles that were retrieved and underwent full article review. 10 articles met the set inclusion criteria, with 7 focusing on social support, 2 on supervisory quality and 1 on both. We found moderate and limited evidence, respectively, that social support and supervisory quality interventions positively impact workplace outcomes. CONCLUSION: There is moderate evidence that social support and limited evidence that supervisory quality interventions have a positive effect on work outcomes.

Job demand and control interventions: a stakeholder-centered best-evidence synthesis of systematic reviews on workplace disability.

BACKGROUND: Physical and psychological job demands in combination with the degree of control a worker has over task completion, play an important role in reducing stress. Occupational stress is an important, modifiable factor affecting work disability. However, the effectiveness of reducing job demands or increasing job control remains unclear, particularly for outcomes of interest to employers, such as absenteeism or productivity. OBJECTIVE: This systematic review reports on job demand and control interventions that impact absenteeism, productivity and financial outcomes. METHODS: A stakeholder-centered best-evidence synthesis was conducted with researcher and stakeholder collaboration throughout. Databases and grey literature were searched for systematic reviews between 2000 and 2012: Medline, EMBASE, the Cochrane Database of Systematic Reviews, DARE, CINAHL, PsycINFO, TRIP, health-evidence.ca, Rehab+, National Rehabilitation Information Center (NARIC), and Institute for Work and Health. Articles were assessed independently by two researchers for inclusion criteria and methodological quality. Differences were resolved through consensus. RESULTS: The search resulted in 3363 unique titles. After review of abstracts, 115 articles were retained for full-text review. 11 articles finally met the inclusion criteria and are summarized in this synthesis. The best level of evidence we found indicates that multimodal job demand reductions for either at-work or off-work workers will reduce disability-related absenteeism. CONCLUSION: In general, the impacts of interventions that aim to reduce job demands or increase job control can be positive for the organization in terms of reducing absenteeism, increasing productivity and cost-effectiveness. However, more high quality research is needed to further assess the relationships and quantify effect sizes for the interventions and outcomes reviewed in this study.

Favorable impact of the interleukin-4 receptor allelic variant I75 on the survival of diffuse large B-cell lymphoma patients demonstrated in a large prospective clinical trial.

BACKGROUND: Recently published data indicate that host germline variations in immune genes can influence the outcome of lymphoma patients. Interleukin (IL)-4 and IL13 are crucial immune factors and may influence the course of the disease. Both cytokines signal through the interleukin-4 receptor (IL4R). Therefore, we investigated whether polymorphisms of IL4, IL13 and IL4R genes could predict the outcome of diffuse large B-cell lymphoma (DLBCL) patients. METHODS: In 228 DLBCL samples of the German High-Grade Non-Hodgkin's Lymphoma Study Group, the polymorphisms of IL4 (-524CT, rs2243250), IL13 (-1069CT, rs1800925) and IL4R (I75V, rs1805010; S503P, rs1805015; Q576R, rs1801275) were analyzed and the soluble interleukin-4 receptor (sIL4R) serum level was measured before the start of chemotherapy. RESULTS: Patients harboring IL4R V75 (IL4R(I75V-AG) and IL4R(I75V-GG)) had shorter overall survival (OS) (P = 0.044) and event-free survival (EFS) (P = 0.056) periods compared with I75 carriers (IL4R(I75V-AA)). Multivariate analysis adjusted to the International Prognostic Index revealed a relative risk of 1.9 for carriers of the IL4R V75 (P = 0.011) in relation to OS. DLBCL patients homozygous for the IL4R I75 and low sIL4R serum levels have the most favorable OS and EFS. CONCLUSIONS: These data support the role for host germline gene variations of immunologically important factors like the IL4R I75V gene variation to predict the survival in DLBCL patients.

Distal and proximal interleukin (IL)-10 promoter polymorphisms associated with risk of cutaneous melanoma development: a case--control study.

Inherited promoter polymorphisms of the interleukin (IL)-10 gene resulting in altered IL-10 production may contribute to a genetic susceptibility for melanoma. We investigated the role of a haplotype from distal as well as proximal polymorphic sites [-7400InDel, -6752AT (rs6676671), -3538AT (rs1800890), -1087AG (rs1800896), -597AC (rs1800872)] of the IL-10 5'-flanking region in a hospital-based case-control study of 165 Caucasian patients with cutaneous melanoma from Germany in comparison with 162 healthy cancer-free Caucasian control participants from the same area matched by age. Using multivariate analysis for the number of nevi and skin type, the IL-10 'higher producing' haplotype ITAGC was found to be significantly associated with a reduced risk of developing melanoma (adjusted P=0.02). Although our findings need to be confirmed by independent and larger multicenter studies, we have described for the first time the association of distal gene variants of the IL-10 gene as an independent risk factor for melanoma.

The Epstein-Barr virus oncoprotein, latent membrane protein-1, reprograms germinal centre B cells towards a Hodgkin's Reed-Sternberg-like phenotype.

Although the latent membrane protein-1 (LMP1) of the Epstein-Barr virus (EBV) is believed to be important for the transformation of germinal centre (GC) B cells, the precise contribution of this viral oncogene to lymphoma development is poorly understood. In this study, we used a non-viral vector-based method to express LMP1 in primary human GC B cells. Gene expression profiling revealed that LMP1 induced in GC B cells transcriptional changes characteristic of Hodgkin's lymphoma cell lines. Strikingly, LMP1 down-regulated the expression of B-cell-specific genes including B-cell receptor components such as CD79A, CD79B, CD19, CD20, CD22, and BLNK. LMP1 also induced the expression of ID2, a negative regulator of B-cell differentiation. Our data suggest that in EBV-positive cases, LMP1 is likely to be a major contributor to the altered transcriptional pattern characteristic of Hodgkin/Reed-Sternberg cells, including the loss of B-cell identity.

The interleukin-10 gene promoter polymorphism -1087AG does not correlate with clinical outcome in non-Hodgkin's lymphoma.

The Interleukin 10 (IL-10) gene is highly polymorphic, and the IL-10(-1087AG) (rs1800896) gene variation is the only so far studied intensively in association with certain diseases. Conflicting data have been published about an association of IL-10(-1087AG) gene variation with lower rates of complete remission and lower overall survival (OS) in patients with diffuse large B-cell lymphoma. To further investigate this in malignant lymphoma, we established the IL-10 genotypes in patients from the NHL-B1/ B2 studies from the German High-Grade Non-Hodgkin's Lymphoma Study Group. In our study, allele frequencies of lymphoma patients are comparable as in healthy controls. No increase of IL-10(-1087G) alleles was found. In addition we did not find any difference in OS or event-free survival between patients with IL-10(-1087AA) and the other genotypes. Comparable results were obtained for the IL-10 loci at -3538 (A/T), -1354 (A/G), -824 (C/T) and -597 (A/C) (rs1800890, rs1800893, rs1800871 and rs1800872).

STAT3 is essential for Hodgkin lymphoma cell proliferation and is a target of tyrphostin AG17 which confers sensitization for apoptosis.

Classical Hodgkin lymphoma (cHL) is a distinct malignancy of the immune system. Despite the progress made in the understanding of the biology of cHL, the transforming events remain to be elucidated. Recently, we demonstrated that the Janus kinase inhibitor AG490 blocked cellular proliferation and STAT3 phosphorylation in cHL. To explore the potential of constitutively activated STAT3 as a drug target and its role in cHL pathogenesis, different cHL cell lines were analyzed. Treatment of cHL cells by the protein tyrosine kinase inhibitor AG17 was associated with inhibition of cellular proliferation and cell cycle arrest. AG17 treatment was accompanied by decreased levels of STAT3 phosphorylation, whereas NF-kappaB and p38/SAPK2 signaling were not inhibited. Incubation with AG17 or AG490 sensitized cHL cells to CD95/Fas/Apo-1 or staurosporine-mediated apoptosis. Coincubation of tyrphostins with staurosporine was accompanied by rapid complete inhibition of STAT3 phosphorylation. RNA interference directed against STAT3 in L428 and L1236 cHL cells demonstrated that STAT3 is essential for cell proliferation of these cHL cells. In conclusion, these findings support the concept that STAT3 signaling is important in the pathogenesis of cHL and tyrphostins are agents for developing new therapeutic strategies.

Mosaics of gene variations in the Interleukin-10 gene promoter affect interleukin-10 production depending on the stimulation used.

Interleukin-10 (IL-10), a cytokine involved in many aspects of the immune response shows interindividual variations in their expression. However, genetic variations of the 5'-flanking region of the IL-10 gene (PIL-10) are poorly characterised with respect to different stimuli. New extended haplo- and genotypes are identified present at differing frequencies in three geographically separated populations. Their influence on IL-10 expression have been assessed in vitro after stimulation of leukocytes with lipopolysaccharide (LPS), dibutyryl-cAMP or following immortalisation with Epstein-Barr virus (lymphoblastoid cell line (LCL)). Interindividual differences of IL-10 production were found to be related to single-nucleotide polymorphisms (SNP) haplotype -6752/-6208 in LCLs (P<0.02), and for haplotypes comprising SNPs -6752/-6208/-3538 after LPS stimulation (P<0.03). Carriers of the IL10.G microsatellite with 22, 24 or 26 dinucleotide repeats linked with the -1087G SNP, exhibited the highest levels of IL-10 expression. Contrasting IL-10 secretion patterns were found for IL10.R microsatellite alleles characterised by 15 dinucleotide repeats: after LPS stimulation this allele was associated with high IL-10 production (P<0.007), but with low IL-10 levels in LCLs (P< 0.038). Thus, the effects of mosaics of genetic elements in the PIL-10 on the capacity of leukocytes to produce IL-10 depend on the agent inducing IL-10 expression.

Simultaneous analysis of interleukin-10 gene microsatellites and single-nucleotide polymorphisms in parallel with tumour necrosis factor and interferon-gamma short tandem repeats by fluorescence-based polymerase chain reaction.

Different cytokine genotypes exist in the population, for example, as a result of selective pressure of infectious diseases. It may be that specific cytokine genotypes that are beneficial by creating a 'proinflammatory' phenotype predispose to severe inflammatory disease with worse clinical outcome. There is individual variation in the production of certain cytokines in relation to their genotypes. IL-10, IFN-gamma and TNF-alpha are key components in the regulation of immune responses and the balance of their expression levels is predictive in certain diseases. To describe cytokine genotypes, a one-tube PCR reaction was developed to analyse simultaneously DNA sequence variations of cytokine genes IL-10, IFN-gamma, and TNF. This multiplex PCR approach was used to provide genotypic data for two geographically independent donor groups from Germany and Gabon. Significant differences were obtained for the majority of sequence variations comparing both populations. However, the SNPs within the 5'-flanking region of the IL-10 gene at position -1087 and -6208 are comparable in their genic and genotypic behaviour. Comparing allelic and genotypic disequilibrium between pairs of loci revealed different association patterns for both populations according to the geographical polymorphism. This assay may improve immunogenetic studies in disease, characterized by disbalanced IL-10, IFN-gamma and TNF-alpha expression.

A new allelic variation within the 5'-flanking region of the interleukin-10 gene.

At -2471 bp from the transcriptional start site of the interleukin-10 (IL-10) gene, the inverted repeat TG/CA was previously identified and designated IL-10.IR. In an analysis of samples from 200 Germans (Caucasian) and 286 Gabonese (Central African), three different alleles, IL-10.IR6, IL-10.IR7 and IL-10.IR8, were identified. In the Caucasians, IL-10.IR6 and IL-10.IR8 were found only once, in each case with IL-10.IR7 as the corresponding second allele.

Semiautomated and simultaneous analysis of the interleukin-10 gene microsatellites IL-10G and IL-10R by fluorescence-based polymerase chain reaction reveals significant differences in allele distributions between Caucasians (Germany) and Africans (Gabon).

Interleukin-10 (IL-10) is an important immunoregulatory cytokine influencing many aspects of the adaptive and inflammatory immune response. Two dinucleotide repeats have been identified in the 5'-UTR of IL-10 and shown to be useful genetic markers in several diseases. A simple, two-colour fluorescence assay was developed for determination of microsatellite fragment length by an automatic sequencer. Using this method polymorphisms at the IL-10G and IL-10R loci of the 5' flanking region of the IL-10 gene can be identified simultaneously. A unified standard nomenclature was applied to the known IL-10G and IL-10R microsatellites. The multiplex PCR approach was used to compare the allele frequencies in two independent donor groups from Germany (Caucasian), comprising 112 and 106 cases, respectively, and one group from Gabon (African) including 91 donors. Significant differences in the allele distribution were found. Both Caucasian populations tested showed no significant differences in their allele and genotype distribution. Whereas in Africans, allele IL-10G25 is rare at 3% compared to 21% in Caucasian, alleles IL-10G22 and G23 are more prevalent in Africans than in Caucasians (22% versus 10% and 26% versus 7%, respectively). Within the IL-10R locus, the allele R13 was observed at 88% in the African group compared to 69% in Caucasians. These data may help immunogenetic studies in diseases, where IL-10 is thought to be deregulated.

Structural characterisation of the distal 5' flanking region of the human interleukin-10 gene.

Interleukin-10 (IL-10) is an important immunoregulatory cytokine. The recent characterisation of the proximal 5' flanking region of IL-10 led to the identification of the promoter region. Two polymorphic dinucleotide repeats and 10 single nucleotide polymorphisms (SNPs) have been identified and suggested to be useful genetic markers in several diseases. We have sequenced a further 5275 bp from -9296 to -4021 of the distal part of the 5' flanking region of the human IL-10 gene from the cosmid clone pWE15-4/11. Our sequence analysis reveals a high density of Alu-repeats within the IL-10 gene locus, including three novel, related structures which we term Alu-IL10 (A-C). Using three overlapping PCR products spanning 5110 bp of this distal part of the IL-10 gene the following single base pair substitutions were identified: at -8571 C/T, -8531 G/A, -6752 A/T, -6208 G/C, -5402 C/G. In addition a heterozygous three base pair deletion at -7400 was observed. The SNPs at -8571 C/T and -8531 G/A are contained within an Alu-repeat. These data should further the understanding of how the IL-10 gene is controlled in man and how its function may vary between individuals.

STAT3 is constitutively activated in Hodgkin cell lines.

Hodgkin disease (HD) represents a malignant lymphoma in which the putative malignant Hodgkin and Reed-Sternberg cells are rare and surrounded by abundant reactive nonmalignant cells. It has been suggested that cytokines such as interleukin-6 (IL-6) are involved in the pathogenesis of the disease. The expression of the IL-6 receptor (IL-6R) complex and its link to the activation of signal transducers and activators of transcription (STAT) molecules in HD cell lines was investigated. Gel retardation and Western blot analyses revealed a high level of constitutively activated STAT3 in 5 of 7 HD cell lines, which could not be detected in Burkitt lymphoma cell lines. Different levels of IL-6R protein were measured in various HD cell lines: L428 and Dev cells were characterized by very low levels of gp80 and gp130, on KMH2 cells only gp130 but no gp80 was detected, whereas L540, L591, HDLM2, and L1236 were positive for both gp80 and gp130, suggesting a possible autocrine stimulation of STAT3. However, a further increase in STAT3 activation on IL-6 or IL-6/soluble IL-6R stimulation was not observed. Neutralizing monoclonal antibodies against IL-6, gp80, gp130, or both receptor subunits did not affect the proliferation or the constitutive activation of STAT molecules in HD cell lines. However, the tyrosine kinase inhibitor AG490 blocked the constitutive activation of STAT3 and inhibited spontaneous growth of HD tumor cells. The evidence suggests abnormal STAT signaling and growth regulation in Hodgkin cell lines. (Blood. 2001;98:762-770)

Immunomagnetic enrichment of CD138 positive cells from weakly infiltrated myeloma patients samples enables the determination of the tumor clone specific IgH rearrangement.

In multiple myeloma, the polymerase chain reaction (PCR) of the Ig heavy chain with allele-specific oligonucleotide (ASO) primers is a common and well-described method of identifying the tumor clone in peripheral blood (PB), bone marrow (BM) or leukapheresis products (LA). A factor which is crucial to the detection of clonal Ig rearrangements lies in the 'purity' of the tumor tissue used for the consensus PCR. We describe the application of a method to enrich CD138 positive myeloma cells derived from weakly infiltrated PB-, BM- and LA-samples. These are subjected to immunomagnetic enrichment with the MACS system, using an CD138 antibody directly conjugated to magnetic beads to obtain an enriched tumor cell population and the subsequent amplification of tumor specific IgH rearrangements. We investigated 29 samples (ten PB, ten BM, nine LA) with a median myeloma cell content of 0.5%. The approach led to a median enrichment factor of 118. Tumor-specific rearrangements could be amplified reproducibly from samples containing less than 0.1% myeloma cells.

Terminal sialylation is altered in airway cells with impaired CFTR-mediated chloride transport.

Reduced terminal sialylation at the surface of airway epithelial cells from patients with cystic fibrosis may predispose them to bacterial infection. To determine whether a lack of chloride transport or misprocessing of mutant cystic fibrosis transmembrane conductance regulator (CFTR) is critical for the alterations in glycosylation, we studied a normal human tracheal epithelial cell line (9/HTEo(-)) transfected with the regulatory (R) domain of CFTR, which blocks CFTR-mediated chloride transport; DeltaF508 CFTR, which is misprocessed, wild-type CFTR; or empty vector. Reduced cAMP-stimulated chloride transport is seen in the R domain and DeltaF508 transfectants. These two cell lines had consistent, significantly reduced binding of elderberry bark lectin, which recognizes terminal sialic acid in the alpha-2,6 configuration. Binding of other lectins, including Maakia amurensis lectin, which recognizes sialic acid in the alpha-2,3 configuration, was comparable in all cell lines. Because the cell surface change occurred in R domain-transfected cells, which continue to express wild-type CFTR, it cannot be related entirely to misprocessed or overexpressed CFTR. It is associated most closely with reduced CFTR activity.