Breast cancer in systemic lupus.

Objective There is a decreased breast cancer risk in systemic lupus erythematosus (SLE) versus the general population. We assessed a large sample of SLE patients, evaluating demographic and clinical characteristics and breast cancer risk. Methods We performed case-cohort analyses within a multi-center international SLE sample. We calculated the breast cancer hazard ratio (HR) in female SLE patients, relative to demographics, reproductive history, family history of breast cancer, and time-dependent measures of anti-dsDNA positivity, cumulative disease activity, and drugs, adjusted for SLE duration. Results There were 86 SLE breast cancers and 4498 female SLE cancer-free controls. Patients were followed on average for 7.6 years. Versus controls, SLE breast cancer cases tended to be white and older. Breast cancer cases were similar to controls regarding anti-dsDNA positivity, disease activity, and most drug exposures over time. In univariate and multivariate models, the principal factor associated with breast cancers was older age at cohort entry. Conclusions There was little evidence that breast cancer risk in this SLE sample was strongly driven by any of the clinical factors that we studied. Further search for factors that determine the lower risk of breast cancer in SLE may be warranted.

The prevalence and determinants of anti-DFS70 autoantibodies in an international inception cohort of systemic lupus erythematosus patients.

Autoantibodies to dense fine speckles 70 (DFS70) are purported to rule out the diagnosis of SLE when they occur in the absence of other SLE-related autoantibodies. This study is the first to report the prevalence of anti-DFS70 in an early, multinational inception SLE cohort and examine demographic, clinical, and autoantibody associations. Patients were enrolled in the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort within 15 months of diagnosis. The association between anti-DFS70 and multiple parameters in 1137 patients was assessed using univariate and multivariate logistic regression. The frequency of anti-DFS70 was 7.1% (95% CI: 5.7-8.8%), while only 1.1% (95% CI: 0.6-1.9%) were monospecific for anti-DFS70. In multivariate analysis, patients with musculoskeletal activity (Odds Ratio (OR) 1.24 [95% CI: 1.10, 1.41]) or with anti-ß2 glycoprotein 1 (OR 2.17 [95% CI: 1.22, 3.87]) were more likely and patients with anti-dsDNA (OR 0.53 [95% CI: 0.31, 0.92]) or anti-SSB/La (OR 0.25 [95% CI: 0.08, 0.81]) were less likely to have anti-DFS70. In this study, the prevalence of anti-DFS70 was higher than the range previously published for adult SLE (7.1 versus 0-2.8%) and was associated with musculoskeletal activity and anti-ß2 glycoprotein 1 autoantibodies. However, 'monospecific' anti-DFS70 autoantibodies were rare (1.1%) and therefore may be helpful to discriminate between ANA-positive healthy individuals and SLE.

A majority of parents of children with peanut allergy fear using the epinephrine auto-injector.

Prompt epinephrine administration is crucial in managing anaphylaxis, but epinephrine auto-injectors (EAIs) are underutilized by patients and their families. Children with peanut allergy were recruited from the Allergy Clinics at the Montreal Children's Hospital, food allergy advocacy organizations and organizations providing products to allergic individuals. Parents of children who had been prescribed an EAI were queried on whether they were fearful of using it and on factors that may contribute to fear. A majority of parents (672/1209 = 56%) expressed fear regarding the use of the EAI. Parents attributed the fear to hurting the child, using the EAI incorrectly or a bad outcome. Parents whose child had longer disease duration or a severe reaction and parents who were satisfied with the EAI training or found it easy to use were less likely to be afraid. Families may benefit from simulation training and more education on the recognition and management of anaphylaxis.

Molecular response of a sub-antarctic population of the blue mussel (Mytilus edulis platensis) to a moderate thermal stress.

The Kerguelen Islands (49°26'S, 69°50'E) represent a unique environment due to their geographical isolation, which protects them from anthropogenic pollution. The ability of the endemic mussel, part of the Mytilus complex, to cope with moderate heat stress was explored using omic tools. Transcripts involved in six major metabolic functions were selected and the qRT-PCR data indicated mainly changes in aerobic and anaerobic energy metabolism and stress response. Proteomic comparisons revealed a typical stress response pattern with cytoskeleton modifications and elements suggesting increased energy metabolism. Results also suggest conservation of protein homeostasis by the long-lasting presence of HSP while a general decrease in transcription is observed. The overall findings are consistent with an adaptive response to moderate stresses in mussels in good physiological condition, i.e. living in a low-impact site, and with the literature concerning this model species. Therefore, local blue mussels could be advantageously integrated into biomonitoring strategies, especially in the context of Global Change.

Leukocytosis and resistance to septic shock in intercellular adhesion molecule 1-deficient mice.

Intercellular adhesion molecule 1 (ICAM-1) is one of three immunoglobulin superfamily members that bind to the integrins lymphocyte function associated 1 (LFA-1) and Mac-1 on leukocytes. We have generated mice that are genetically and functionally deficient in ICAM-1. These mice have elevated numbers of circulating neutrophils and lymphocytes, as well as diminished allogeneic T cell responses and delayed type hypersensitivity. Mutant mice are resistant to lethal effects of high doses of endotoxin (lipopolysaccharide [LPS]), and this correlates with a significant decrease in neutrophil infiltration in the liver. Production of inflammatory cytokines such as tumor necrosis factor alpha or interleukin 1 is normal in ICAM-1-deficient mice, and thus protection appears to be related to a diminution in critical leukocyte-endothelial interactions. After sensitization with D-galactosamine (D-Gal), ICAM-1-deficient mice are resistant to the lethal effect of low doses of exotoxin (Staphylococcus aureus enterotoxin B [SEB]), which has been shown to mediate its toxic effects via the activation of specific T cells. In this model, ICAM-1-mediated protection against SEB lethality correlates with a decrease in the systemic release of inflammatory cytokines, as well as with prevention of extensive hepatocyte necrosis and hemorrhage. ICAM-1-deficient mice sensitized with D-Gal, however, are not protected from lethality when challenged with low doses of endotoxin (LPS). These studies show that the different contribution of ICAM-1 in the activation of either T cells or macrophages is decisive for the fatal outcome of the shock in these two models. This work suggests that anti-ICAM-1 therapy may be beneficial in both gram-positive and -negative septic shock, either by reducing T cell activation or by diminishing neutrophil infiltration.

SLE patients with renal damage incur higher health care costs.

OBJECTIVES: To compare costs and quality of life (QoL) between SLE patients with and without renal damage. METHODS: Seven hundred and fifteen patients were surveyed semi-annually over 4 yrs on health care use and productivity loss and annually on QoL. Cumulative direct and indirect costs (2006 Canadian dollars) and QoL (average annual change in SF-36) were compared between patients with and without renal damage [Systemic Lupus International Collaborating Clinics/ACR Damage Index (SLICC/ACR DI)] using simultaneous regressions. RESULTS: At study conclusion, for patients with the renal subscale of the SLICC/ACR DI = 0 (n = 634), 1 (n = 54), 2 (n = 15) and 3 (n = 12), mean 4-yr cumulative direct costs per patient (95% CI) were $20,337 ($18,815, $21,858), $27,869 ($19,230, $36,509), $51,191 ($23,463, $78,919) and $99,544 ($57,102, $141,987), respectively. In a regression where the renal subscale of the SLICC/ACR DI was a single indicator variable, on average (95% CI), each unit increase in renal damage was associated with a 24% (15%, 33%) increase in direct costs. In a regression where each level in the renal subscale was an indicator variable, patients with end-stage renal disease incurred 103% (65%, 141%) higher direct costs than those without renal damage. Cumulative indirect costs and annual change in the SF-36 summary scores did not differ between patients. CONCLUSIONS: SLE patients with renal damage incurred higher direct costs, but did not experience a poorer QoL. QoL may be more influenced by concurrent renal activity than accumulated renal damage, which can occur at any time and patients may gradually habituate to their compromised health state.

In vitro expression of MMP-2 and MMP-9 in glioma cells following exposure to inflammatory mediators.

Progression of glioma is associated with local degenerative processes which are attributed to the activity of gelatinases. As glioma cells are candidate for secretion of these enzymes, we have studied in vitro the potential of cytokines (interleukin-1alpha (IL-1), tumor necrosis factor-alpha (TNFalpha) and transforming growth factor-beta (TGFbeta2)) to regulate the expression of gelatinase A and B (Gels A and B, respectively) in two glioma cells of human (A172) and rat origin (C6). We showed that IL-1 and TNFalpha both induced gene expression and protein secretion of Gel B in both cell lines, as revealed by RT-PCR and gelatin zymography, respectively. In C6 cells, TNFalpha had no effect on Gel A constitutive expression while IL-1 increased its production, but only at high doses. We have also demonstrated that TGFbeta2 inhibited both IL-1- or TNFalpha-induced gene expression and Gel B production in a dose-dependent manner but had no effect on Gel A secretion. The effect of TGFbeta2 on Gel B secretion was reversed by phorbol myristate acetate (PMA). Taken together, these data suggest that IL-1, TNFalpha and TGFbeta2 tightly regulate Gel B secretion in glioma cells, an enzyme which is believed to play an important role in the local invasion of brain tissue by tumor cells.

Dendritic cells prevent radiation-induced thymic lymphoma.

Thymic lymphomas develop in C57BL/Ka mice within 36 weeks after split-dose X-irradiation. Lymphoma development can be abrogated in such mice by the injection of syngeneic bone marrow from healthy donors. The abrogation mechanism is unknown, but since bone marrow supplies the thymus with precursors of thymocytes and of dendritic cells, we tested the ability of early thymocytes and of immortalized thymic dendritic cells to abrogate lymphomagenesis. Fifteen weeks after irradiation, mice which had received bone marrow or dendritic cells had an equally low incidence of lymphoma, whereas mice which had received thymocytes or which had been only irradiated developed equally high levels of lymphomas, indicating that thymic dendritic cells played a key role in the prevention of lymphoma development. When thymuses from 15-week survivors were tested for pre-lymphoma cells, those from dendritic cell-treated mice proved to be endowed with a level of lymphomagenic potential intermediate between that from bone marrow-treated mice (nonlymphomagenic) and that from untreated or thymocyte-treated mice (highly lymphomagenic). These data indicate that lymphoma abrogation by bone marrow cells involves the participation of marrow-derived thymic dendritic cells.

Upregulation of galectin-7 in murine lymphoma cells is associated with progression toward an aggressive phenotype.

We have previously shown that ICAM-1-deficient mice were resistant to lymphoma dissemination of intravenously injected 164T2 lymphoma cells. Highly aggressive variants of this cell line, however, could overcome this resistance. To discern the complex pattern of gene expression involved in the evolution of aggressiveness in lymphoma cells, we compared the transcriptome of 164T2 cells with that of their aggressive variants using cDNA arrays. We identified several genes that were differentially expressed in nonmetastatic lymphoma cells and their metastatic variants. Galectin-7, associated with the development of chemically induced mammary carcinoma, was one such gene whose expression was significantly upregulated. We showed that it was constitutively expressed in aggressive variants, at both mRNA and protein levels. Galectin-7 expression in aggressive lymphoma cells was induced upon in vivo selection in several organs, including the thymus, the spleen and kidneys. We also showed that treatment of nonaggressive lymphoma cells with 5-aza-2'-deoxycytidine was sufficient to induce galectin-7 gene expression. This report is the first to show that galectin-7 is expressed in aggressive lymphoma.

Resistance to RadLV-induced leukemia: non-participation of splenic natural killer cells.

The phenotypic expression of genetically determined resistance to radiation leukemia virus (RadLV)-induced leukemia in mice has been shown to reside in the bone marrow. Because the bone marrow contains precursors of natural killer (NK) cells, known to play a role in retrovirally induced infections, and because these cells have been suggested as participating in resistance to radiation-induced leukemia, it was pertinent to establish whether their levels differed in strains of mice susceptible and resistant to leukemia. We therefore tested splenic NK cell levels in C57BL/Ka (susceptible) and B10.A(5R) (resistant) mice before viral inoculation, immediately after viral inoculation, and throughout the preleukemic period and showed that they were not different. This indicates that splenic NK cell levels have no bearing on the resistance to RadLV-induced leukemia and that other immune or non-immune mechanisms must be sought.

Expression of glycophosphatidylinositol-anchored and -non-anchored isoforms of vascular cell adhesion molecule 1 in murine stromal and endothelial cells.

Monoclonal antibodies to murine vascular cell adhesion molecule-1 (VCAM-1, CD106) revealed not only the expected VCAM-1 molecule with an apparent molecular weight of 100 kDa, but also a molecule with a smaller size of 46 kDa in stromal cells and stimulated endothelial cells. Peptide mapping suggested the 46 kDa and 100 kDa proteins were closely related. The 46 kDa, but not 100 kDa protein, was cleaved from the cell surface with phosphatidylinositol-specific phospholipase C (PI-PLC), showing that the 46 kDa protein was a GPI-linked molecule. The 46 kDa and 100 kDa isoforms of VCAM-1 were shown to be N-glycosylated, have similar kinetics of biosynthesis, and to be partially shed from the cell surface with a slight reduction of size. TNF-alpha induced both isoforms of VCAM-1 with a similar time course of appearance on the surface of endothelial cells. The relative amounts of the 46 kDa and 100 kDa isoforms depended on the cell type examined. The GPI-anchored isoform is functionally important, because on a cell on which it was expressed almost as well as the 100 kDa isoform, treatment with PI-PLC reduced VLA-4-dependent conjugate formation.

Leukocyte elastase in murine and human non-Hodgkin lymphomas.

Extracellular proteases play a crucial role in the invasive behavior of normal and transformed leukocytes. Thus far, however, most of the attention has been focused on members of the family of matrix metalloproteinases. In this work, we show that lymphoma cells can express leukocyte elastase (LE) and recruit the enzyme at their surface via ICAM-1. The expression of LE by lymphoma cells was augmented significantly by stimulation with IL-6 and IL-13, both of which also induced the expression of MMP-9. Although LE and IL-13 transcripts were detected in several non-Hodgkin's lymphomas, immunohistochemical analysis of lymphoma tissues also showed that LE was strongly expressed in infiltrating leukocytes. Given the spectrum of key molecules that can be cleaved by LE and that LE and MMP-9 are involved in the invasive behavior of normal or transformed leukocytes, our results raise the hypothesis that LE plays a crucial role in the multistep processes of inflammation and lymphoma metastasis.

UEA-I-binding to thymic medullary epithelial cells selectively reduces numbers of cortical TCRalphabeta+ thymocytes in FTOCs.

Thymic medullary epithelial cells (TMECs) constitute a major stromal cell type, the function of which is incompletely understood. Some TMECs express L-fucose-glycosylated proteins on their plasma membrane; these have been shown to specifically bind the lectin UEA-I. We exploited this observation to investigate the consequences of in situ blockage of TMECs in FTOCs by UEA-I. In UEA-I-treated FTOCs, we noted a decreased cellularity among TCRalphabeta+ but not TCRgammadelta+ cells. In fact, CD3- and CD3lo cortical cells were markedly depleted, while CD3hi cells were unaffected. Since the affected cell subsets are in a different compartment from that where UEA-I binding occurs, it is likely that the effect is mediated through a soluble factor. Two possible mechanisms are proposed: a reduced activation of either TMECs or of medullary thymocytes which normally bind to them, results in lowered production of soluble factors responsible for cortical thymocyte proliferation. Alternately, the binding of UEA-I to TMECs could activate the latter to produce signals inhibitory to cortical thymocytes.

Bone marrow phenotype determines genetic resistance to RadLV-induced leukemia in radiation chimeric mice.

The development of RadLV-induced T-cell leukemia is a multistep process which evolves along the bone marrow-thymus axis. This process has been shown to be under the control of resistance and susceptibility genes. The relative importance of bone marrow and thymic phenotypes in this genetic control have not been established. We have constructed radiation chimeras with bone marrow from susceptible C57BL/Ka and thymus from resistant B10.A(5R) mice (and vice versa). The rate of leukemia development in the various groups indicates that the phenotype of the bone marrow and not that of the thymus determines the expression of resistance or susceptibility.

Dissemination of T cell lymphoma to target organs: a post-homing event implicating ICAM-1 and matrix metalloproteinases.

There is increasing evidence that metastasis of a tumor cell (its ability to induce the "development of a tumor" at distant sites following intravasation) is manifested only after homing to distant site(s). All tumor cells, however, do not necessarily undergo uncontrolled cellular division to form secondary tumors once they have "homed" to a target site. One of the major rate-limiting steps in metastasis is in fact related to the ability of the extravasated tumor cells to find an appropriate "nest", where favorable growth conditions will allow them to form a secondary tumor upon massive cell division (1). But to establish such a favorable nest (referred herein as the "nidification" process), tumor cells must penetrate deep into the stroma of the target tissue. This process is facilitated when tumor cells produce of specific proteases, which degrade structural proteins of the extracellular matrix (2,3). The production of proteases by stromal cells can also occur; these enzymes will degrade stroma surrounding the tumor cells, resulting in a massive remodeling of the local parenchyma that may interfere with the vital functions of a target organ as well as help nidification (4). In this review, we focus our attention on post-extravasation events involving adhesion molecules and MMP in the metastatic process of lymphoma cells. We propose that during dissemination of LFA-1-positive lymphoma cells to peripheral organs, the interaction between lymphoma cells and vascular endothelial cells upregulates the local expression of MMP and TIMPs. Since control of lymphoma metastasis appears to occur at the post-extravasation level, we hypothesize that in addition to extravasation, adhesion molecules are implicated in the control of post-extravasation events.

Altered organ accumulation of oligonucleotides using polyethyleneimine grafted with poly(ethylene oxide) or pluronic as carriers.

Passive targeting provides a simple strategy based on natural properties of the carriers to deliver DNA molecules to desired compartments. Polyethylenimine (PEI) is a potent non-viral system that has been known to deliver efficiently both plasmids and oligonucleotides (ODNs) in vitro. However, in vivo systemic administration of DNA/PEI complexes has encountered significant difficulties because these complexes are toxic and have low biodistribution in target tissues. This study evaluates PEI grafted with poly(ethylene oxide) (PEO(8K)-g-PEI(2K)) and PEI grafted with non-ionic amphiphilic block copolymer, Pluronic P85 (P85-g-PEI(2K)) as carriers for systemic delivery of ODNs. Following i.v. injection an antisense ODN formulated with PEO(8K)-g-PEI(2K) accumulated mainly in kidneys, while the same ODN formulated with P85-g-PEI(2K) was found almost exclusively in the liver. Furthermore, in the case of the animals injected with the P85-g-PEI(2K)-based complexes most of the ODN was found in hepatocytes, while only a minor portion of ODN was found in the lymphocyte/monocyte populations. The results of this study suggest that formulating ODN with PEO(8K)-g-PEI(2K) and P85-g-PEI(2K) carriers allows targeting of the ODN to the liver or kidneys, respectively. The variation in the tissue distribution of ODN observed with the two carriers is probably due to the different hydrophilic-lipophilic balance of the polyether chains grafted to PEI in these molecules. Therefore, polyether-grafted PEI carriers provide a simple way to enhance ODN accumulation in a desired compartment without the need of a specific targeting moiety.

Block and graft copolymers and NanoGel copolymer networks for DNA delivery into cell.

Self-assembling complexes from nucleic acids and synthetic polymers are evaluated for plasmid and oligonucleotide (oligo) delivery. Polycations having linear, branched, dendritic. block- or graft copolymer architectures are used in these studies. All these molecules bind to nucleic acids due to formation of cooperative systems of salt bonds between the cationic groups of the polycation and phosphate groups of the DNA. To improve solubility of the DNA/polycation complexes, cationic block and graft copolymers containing segments from polycations and non-ionic soluble polymers, for example, poly(ethylene oxide) (PEO) were developed. Binding of these copolymers with short DNA chains, such as oligos, results in formation of species containing hydrophobic sites from neutralized DNA polycation complex and hydrophilic sites from PEO. These species spontaneously associate into polyion complex micelles with a hydrophobic core from neutralized polyions and a hydrophilic shell from PEO. Such complexes are very small (10-40 nm) and stable in solution despite complete neutralization of charge. They reveal significant activity with oligos in vitro and in vivo. Binding of cationic copolymers to plasmid DNA forms larger (70-200 nm) complexes. which are practically inactive in cell transfection studies. It is likely that PEO prevents binding of these complexes with the cell membranes ("stealth effect"). However attaching specific ligands to the PEO-corona can produce complexes, which are both stable in solution and bind to target cells. The most efficient complexes were obtained when PEO in the cationic copolymer was replaced with membrane-active PEO-b-poly(propylene oxide)-b-PEO molecules (Pluronic 123). Such complexes exhibited elevated levels of transgene expression in liver following systemic administration in mice. To increase stability of the complexes, NanoGel carriers were developed that represent small hydrogel particles synthesized by cross-linking of PEI with double end activated PEO using an emulsification/solvent evaporation technique. Oligos are immobilized by mixing with NanoGel suspension, which results in the formation of small particles (80 nm). Oligos incorporated in NanoGel are able to reach targets within the cell and suppress gene expression in a sequence-specific fashion. Further. loaded NanoGel particles cross-polarized monolayers of intestinal cells (Caco-2) suggesting potential usefulness of these systems for oral administration of oligos. In conclusion the approaches using polycations for gene delivery for the design of gene transfer complexes that exhibit a very broad range of physicochemical and biological properties, which is essential for design of a new generation of more effective non-viral gene delivery systems.

Application of a nomogram for exercise capacity in women with systemic lupus erythematosus.

The aim of this study is to examine the exercise capacity in women with systemic lupus erythematosus (SLE). Women with SLE underwent exercise testing; their performance was compared to nomogram predictions. We assessed the potential effects of disease activity and cumulative damage on exercise capacity. We evaluated 52 female SLE patients aged >35 years. The mean workload achieved was somewhat higher than the nomogram predictions. However, over one fifth of the women performed at a very poor level, which in the general population is associated with a twofold increased risk of cardiovascular disease. Compared to other subjects, participants who did poorly tended toward higher disease activity, higher body mass index, and greater smoking prevalence, although the results were not definitive. Exercise testing may be used to identify a subpopulation of lupus patients with a low level of fitness. Extrapolating from general population data, these individuals are likely at particular risk for cardiovascular disease and may, therefore, benefit the most from aggressive cardiovascular risk factor reduction.

Triggering of T-cell leukemia and dissemination of T-cell lymphoma in MMP-9-deficient mice.

Previous studies have shown that high levels of MMP-9 can be detected in the serum of patients with various lymphoid malignancies and in leukemia/lymphoma culture supernatants. Indeed, aggressive forms of lymphoma constitutively produce MMP-9 and its elevated levels in the serum or in tissues correlate with advanced stage and poor patient survival. In vitro, MMP-9, which is also produced by the host peritumoral cells in response to the presence of tumors, plays an important role in migration of tumor cells through artificial basement membranes or endothelial cells. In this study, using MMP-9-deficient mice, we show that absence of MMP-9 does not prevent the development of primary T-cell leukemia. Furthermore, MMP-9-deficient cell lines retained their tumorigenic potential, as shown by their ability to induce thymic lymphoma in young syngeneic wild-type animals. In addition, these MMP-9-deficient tumor cells disseminate in normal mice, or mice that are deficient for MMP-9, indicating that tumor growth and dissemination can occur in total absence of MMP-9. These results show for the first time than lymphoma growth can occur in total absence of MMP-9 and have consequences for therapy of invasive cancers with inhibitors of MMPs.