NOX activation in reactive astrocytes regulates astrocytic LCN2 expression and neurodegeneration.

Reactive astrocytes (RA) secrete lipocalin-2 (LCN2) glycoprotein that regulates diverse cellular processes including cell death/survival, inflammation, iron delivery and cell differentiation. Elevated levels of LCN2 are considered as a biomarker of brain injury, however, the underlying regulatory mechanisms of its expression and release are not well understood. In this study, we investigated the role of astrocytic Na+/H+ exchanger 1 (NHE1) in regulating reactive astrocyte LCN2 secretion and neurodegeneration after stroke. Astrocyte specific deletion of Nhe1 in Gfap-CreER+/-;Nhe1f/f mice reduced astrogliosis and astrocytic LCN2 and GFAP expression, which was associated with reduced loss of NeuN+ and GRP78+ neurons in stroke brains. In vitro ischemia in astrocyte cultures triggered a significant increase of secreted LCN2 in astrocytic exosomes, which caused neuronal cell death and neurodegeneration. Inhibition of NHE1 activity during in vitro ischemia with its potent inhibitor HOE642 significantly reduced astrocytic LCN2+ exosome secretion. In elucidating the cellular mechanisms, we found that stroke triggered activation of NADPH oxidase (NOX)-NF-κB signaling and ROS-mediated LCN2 expression. Inhibition of astrocytic NHE1 activity attenuated NOX signaling and LCN2-mediated neuronal apoptosis and neurite degeneration. Our findings demonstrate for the first time that RA use NOX signaling to stimulate LCN2 expression and secretion. Blocking astrocytic NHE1 activity is beneficial to reduce LCN2-mediated neurotoxicity after stroke.

Blockade of Cell Volume Regulatory Protein NKCC1 Increases TMZ-Induced Glioma Apoptosis and Reduces Astrogliosis.

Glioma is one of the most common primary malignant tumors of the central nervous system accounting for approximately 40% of all intracranial tumors. Temozolomide is a conventional chemotherapy drug for adjuvant treatment of patients with high-risk gliomas, including grade II to grade IV. Our bioinformatic analysis of The Cancer Genome Atlas and Chinese Glioma Genome Atlas datasets and immunoblotting assay show that SLC12A2 gene and its encoded Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) protein are abundantly expressed in grade II-IV gliomas. NKCC1 regulates cell volume and intracellular Cl- concentration, which promotes glioma cell migration, resistance to temozolomide, and tumor-related epilepsy in experimental glioma models. Using mouse syngeneic glioma models with intracranial transplantation of two different glioma cell lines (GL26 and SB28), we show that NKCC1 protein in glioma tumor cells as well as in tumor-associated reactive astrocytes was significantly upregulated in response to temozolomide monotherapy. Combination therapy of temozolomide with the potent NKCC1 inhibitor bumetanide reduced tumor proliferation, potentiated the cytotoxic effects of temozolomide, decreased tumor-associated reactive astrogliosis, and restored astrocytic GLT-1 and GLAST glutamate transporter expression. The combinatorial therapy also led to suppressed tumor growth and prolonged survival of mice bearing GL26 glioma cells. Taken together, these results demonstrate that NKCC1 protein plays multifaceted roles in the pathogenesis of glioma tumors and presents as a therapeutic target for reducing temozolomide-mediated resistance and tumor-associated astrogliosis.

Elevated Na/H exchanger 1 (SLC9A1) emerges as a marker for tumorigenesis and prognosis in gliomas.

BACKGROUND: Sodium/hydrogen exchanger 1 (NHE1), encoded by the SLC9A1 gene (SoLute Carrier family 9A1) in humans, is the main H+ efflux mechanism in maintaining alkaline intracellular pH (pHi) and Warburg effects in glioma. However, to date, there are no clinical studies exploring pharmacological inhibition of NHE1 protein in cancer treatment. In this study, we investigated NHE1 expression in gliomas and its relationship with glioma clinical outcome. METHODS: The Chinese Glioma Genome Atlas (CGGA) dataset containing transcriptome sequencing data of 325 glioma samples and the Cancer Genome Atlas (TCGA) with 698 glioma mRNAseq data were analyzed in this study. Mouse SB28 and GL26 intracranial syngeneic glioma models in C57BL/6 J mice were established to investigate NHE1 expression and impact of NHE1 protein inhibition with its inhibitor HOE642 on tumorigenesis and anti-PD1 therapy. Tumor angiogenesis, immunogenicity, and progression were assessed by immunofluorescence staining and flow cytometric profiling. RESULTS: Analysis of SLC9A1 mRNA expression in two data sets, CGGA and TCGA, reveals significantly higher SLC9A1 mRNA levels in higher grade gliomas. The SLC9A1 mRNA expression was especially enriched in isocitrate dehydrogenase (IDH)1/2 wild-type glioblastoma (GBM) and in mesenchymal glioma subtypes. Worsened survival probabilities were correlated with the elevated SLC9A1 mRNA levels in gliomas. The underlying mechanisms include promoting angiogenesis, and extracellular matrix remodeling. Increased SLC9A1 mRNA expression was also associated with tumor-associated macrophage accumulation. NHE1 inhibitor HOE642 reduced glioma volume, invasion, and prolonged overall survival in mouse glioma models. Blockade of NHE1 protein also stimulated immunogenic tumor microenvironment via activating CD8 T-cell accumulation, increasing expression of interferon-gamma (Ifng), and sensitized animals to anti-PD-1 therapy. CONCLUSION: Our findings strongly suggest that NHE1 protein emerges as a marker for tumorigenesis and prognosis in glioma. Blocking NHE1 protein is a novel strategy for adjuvant anti-cancer therapies.

Blockade of Na/H exchanger stimulates glioma tumor immunogenicity and enhances combinatorial TMZ and anti-PD-1 therapy.

The weak immunogenicity of gliomas presents a barrier for effective immunotherapy. Na/H exchanger isoform 1 (NHE1) maintains alkaline intracellular pH (pHi) of glioma cells and acidic microenvironment. In addition, NHE1 is expressed in tumor-associated microglia and tumor-associated macrophages (TAMs) and involved in protumoral communications between glioma and TAMs. Therefore, we hypothesize that NHE1 plays a role in developing tumor resistance and immunosuppressive tumor microenvironment. In this study, we investigated the efficacy of pharmacological inhibition of NHE1 on combinatorial therapies. Here we show that temozolomide (TMZ) treatment stimulates NHE1 protein expression in two intracranial syngeneic mouse glioma models (SB28, GL26). Pharmacological inhibition of NHE1 potentiated the cytotoxic effects of TMZ, leading to reduced tumor growth and increased median survival of mice. Blockade of NHE1 stimulated proinflammatory activation of TAM and increased cytotoxic T cell infiltration into tumors. Combining TMZ, anti-PD-1 antibody treatment with NHE1 blockade significantly prolonged the median survival in the mouse glioma model. These results demonstrate that pharmacological inhibition of NHE1 protein presents a new strategy for potentiating TMZ-induced cytotoxicity and increasing tumor immunogenicity for immunotherapy to improve glioma therapy.

Selective role of Na+ /H+ exchanger in Cx3cr1+ microglial activation, white matter demyelination, and post-stroke function recovery.

Na+ /H+ exchanger (NHE1) activation is required for multiple microglial functions. We investigated effects of selective deletion of microglial Nhe1 in Cx3cr1-CreER ;Nhe1f/f mice on neuroinflammation and tissue repair after ischemic stroke. Infarct volume was similar in corn oil or tamoxifen (Tam)-treated mice at 48 hr and 14 days post-stroke. However, the Tam-treated mice showed significantly higher survival rate and faster neurological function recovery during day 1-14 post-stroke. Deletion of microglial Nhe1 prevented the elevation of CD11b+ /CD45low-med microglia in the ischemic hemisphere at day 3 post-stroke, but stimulated expression of Ym1, CD68, TGF-ß, IL-10, decreased expression of CD86 and IL-1ß, and reduced GFAP+ reactive astrocytes. Moreover, at day 14 post-stroke, enhanced white matter myelination was detected in the microglial Nhe1 deleted mice. In comparison, neuronal Nhe1-null mice (the CamKII-Cre+/- ;Nhe1f/f mice) showed a significant reduction in both acute and subacute infarct volume, along with increased survival rate and moderate neurological function recovery. However, these neuronal Nhe1-null mice did not exhibit reduced activation of CD11b+ /CD45low-med microglia or CD11b+ /CD45hi macrophages in the ischemic brains, and they exhibited no reductions in white matter lesions. Taken together, this study demonstrated that deletion of microglial and neuronal Nhe1 had differential effects on ischemic brain damage. Microglial NHE1 is involved in pro-inflammatory responses during post-stroke brain tissue repair. In contrast, neuronal NHE1 activation is directly associated with the acute ischemic neuronal injury but not inflammation. Our study reveals that NHE1 protein is a potential therapeutic target critical for differential regulation of ischemic neuronal injury, demyelination and tissue repair.

Deletion of the WNK3-SPAK kinase complex in mice improves radiographic and clinical outcomes in malignant cerebral edema after ischemic stroke.

The WNK-SPAK kinase signaling pathway controls renal NaCl reabsorption and systemic blood pressure by regulating ion transporters and channels. A WNK3-SPAK complex is highly expressed in brain, but its function in this organ remains unclear. Here, we investigated the role of this kinase complex in brain edema and white matter injury after ischemic stroke. Wild-type, WNK3 knockout, and SPAK heterozygous or knockout mice underwent transient middle cerebral artery occlusion. One cohort of mice underwent magnetic resonance imaging. Ex-vivo brains three days post-ischemia were imaged by slice-selective spin-echo diffusion tensor imaging magnetic resonance imaging, after which the same brain tissues were subjected to immunofluorescence staining. A second cohort of mice underwent neurological deficit analysis up to 14 days post-transient middle cerebral artery occlusion. Relative to wild-type mice, WNK3 knockout, SPAK heterozygous, and SPAK knockout mice each exhibited a >50% reduction in infarct size and associated cerebral edema, significantly less demyelination, and improved neurological outcomes. We conclude that WNK3-SPAK signaling regulates brain swelling, gray matter injury, and demyelination after ischemic stroke, and that WNK3-SPAK inhibition has therapeutic potential for treating malignant cerebral edema in the setting of middle cerebral artery stroke.

Administration of DHA Reduces Endoplasmic Reticulum Stress-Associated Inflammation and Alters Microglial or Macrophage Activation in Traumatic Brain Injury.

We investigated the effects of the administration of docosahexaenoic acid (DHA) post-traumatic brain injury (TBI) on reducing neuroinflammation. TBI was induced by cortical contusion injury in Sprague Dawley rats. Either DHA (16 mg/kg in dimethyl sulfoxide) or vehicle dimethyl sulfoxide (1 ml/kg) was administered intraperitonially at 5 min after TBI, followed by a daily dose for 3 to 21 days. TBI triggered activation of microglia or macrophages, detected by an increase of Iba1 positively stained microglia or macrophages in peri-lesion cortical tissues at 3, 7, and 21 days post-TBI. The inflammatory response was further characterized by expression of the proinflammatory marker CD16/32 and the anti-inflammatory marker CD206 in Iba1(+) microglia or macrophages. DHA-treated brains showed significantly fewer CD16/32(+) microglia or macrophages, but an increased CD206(+) phagocytic microglial or macrophage population. Additionally, DHA treatment revealed a shift in microglial or macrophage morphology from the activated, amoeboid-like state into the more permissive, surveillant state. Furthermore, activated Iba1(+) microglial or macrophages were associated with neurons expressing the endoplasmic reticulum (ER) stress marker CHOP at 3 days post-TBI, and the administration of DHA post-TBI concurrently reduced ER stress and the associated activation of Iba1(+) microglial or macrophages. There was a decrease in nuclear translocation of activated nuclear factor kappa-light-chain-enhancer of activated B cells protein at 3 days in DHA-treated tissue and reduced neuronal degeneration in DHA-treated brains at 3, 7, and 21 days after TBI. In summary, our study demonstrated that TBI mediated inflammatory responses are associated with increased neuronal ER stress and subsequent activation of microglia or macrophages. DHA administration reduced neuronal ER stress and subsequent association with microglial or macrophage polarization after TBI, demonstrating its therapeutic potential to ameliorate TBI-induced cellular pathology.

WNK1-OSR1 kinase-mediated phospho-activation of Na+-K+-2Cl- cotransporter facilitates glioma migration.

BACKGROUND: The bumetanide (BMT)-sensitive Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) maintains cell volume homeostasis by increasing intracellular K+ and Cl- content via regulatory volume increase (RVI). Expression levels of NKCC1 positively correlate with the histological grade and severity of gliomas, the most common primary adult brain tumors, and up-regulated NKCC1 activity facilitates glioma cell migration and apoptotic resistance to the chemotherapeutic drug temozolomide (TMZ). However, the cellular mechanisms underlying NKCC1 functional up-regulation in glioma and in response to TMZ administration remain unknown. METHODS: Expression of NKCC1 and its upstream kinases With-No-K (Lysine) kinase 1 (WNK1) and oxidative stress-responsive kinase-1 (OSR1) in different human glioma cell lines and glioma specimens were detected by western blotting and immunostaining. Live cell imaging and microchemotaxis assay were applied to record glioma cell movements under different treatment conditions. Fluorescence indicators were utilized to measure cell volume, intracellular K+ and Cl- content to reflect the activity of NKCC1 on ion transportation. Small interfering RNA (siRNA)-mediated knockdown of WNK1 or OSR1 was used to explore their roles in regulation of NKCC1 activity in glioma cells. Results of different treatment groups were compared by one-way ANOVA using the Bonferroni post-hoc test in the case of multiple comparisons. RESULTS: We show that compared to human neural stem cells and astrocytes, human glioma cells exhibit robust increases in the activation and phosphorylation of NKCC1 and its two upstream regulatory kinases, WNK1 and OSR1. siRNA-mediated knockdown of WNK1 or OSR1 reduces intracellular K+ and Cl- content and RVI in glioma cells by abolishing NKCC1 regulatory phospho-activation. Unexpectedly, TMZ activates the WNK1/OSR1/NKCC1 signaling pathway and enhances glioma migration. Pharmacological inhibition of NKCC1 with its potent inhibitor BMT or siRNA knockdown of WNK1 or OSR1 significantly decreases glioma cell migration after TMZ treatment. CONCLUSION: Together, our data show a novel role for the WNK1/OSR1/NKCC1 pathway in basal and TMZ-induced glioma migration, and suggest that glioma treatment with TMZ might be improved by drugs that inhibit elements of the WNK1/OSR1/NKCC1 signaling pathway.

Inhibition of Na(+)-K(+)-2Cl(-) cotransporter isoform 1 accelerates temozolomide-mediated apoptosis in glioblastoma cancer cells.

The hallmark of apoptosis is a significant reduction in cell volume (AVD) resulting from loss of K(+)(i) and Cl(-)(i). Loss of cell volume and lowering of ionic strength of intracellular K(+) and Cl(-) occur before any other detectable characteristics of apoptosis. In the present study, temozolomide (TMZ) triggered loss of K(+)(i) and Cl(-)(i) and AVD in primary glioblastoma multiforme (GBM) cancer cells (GC) and GC cancer stem cells (GSC). We hypothesize that Na(+)-K(+)-2Cl(-) cotransporter isoform 1 (NKCC1) counteracts AVD during apoptosis in GBM cancer cells by regulating cell volume and Cl(-) homeostasis. NKCC1 protein was expressed in both GC and GSC and played an essential role in regulatory volume increase (RVI) in response to hypertonic cell shrinkage and isotonic cell shrinkage. Blocking NKCC1 activity with its potent inhibitor bumetanide abolished RVI. These cells maintained a basal [Cl(-)](i) (~ 68 mM) above the electrochemical equilibrium for Cl(-)(i). NKCC1 also functioned to replenish Cl(-)(i) levels following the loss of Cl(-)(i). TMZ-treated cells exhibited increased phosphorylation of NKCC1 and its up-stream novel Cl(-)/volume-sensitive regulatory kinase WNK1. Inhibition of NKCC1 activity with bumetanide accelerated AVD, early apoptosis, as well as activation of caspase-3 and caspase-8. Taken together, this study strongly suggests that NKCC1 is an essential mechanism in GBM cells to maintain K(+), Cl(-), and volume homeostasis to counteract TMZ-induced loss of K(+), Cl(-) and AVD. Therefore, blocking NKCC1 function augments TMZ-induced apoptosis in glioma cells.

Chlorin p6 preferentially localizes in endoplasmic reticulum and Golgi apparatus and inhibits Ca(2+) release from intracellular store.

Subcellular localization of chlorin p6 in human cerebral glioma (U-87MG) cells was studied using laser scanning confocal microscopy. Localization in sub cellular organelles was ascertained by double labeling with specific fluorescent markers of subcellular organelles. The results reveal that chlorin p6 binds to multiple cellular sites but preferential binding sites are endoplasmic reticulum and Golgi apparatus and it does not bind to mitochondria. Significantly the drug localization pattern of proliferating and differentiated cells was notably distinct. In proliferating cells the internalization of drug was faster than in differentiated cells. Localization of chlorin p6 into the cells inhibited Ca(2+) release from endoplasmic reticulum and deregulated cellular Ca(2+) signalling. These results suggest that the fluorescence imaging pattern of chlorin p6 could be useful in identifying the proliferating and differentiated population of cells in tumor tissue.

Warfarin thromboprophylaxis in cancer patients with central venous catheters (WARP): an open-label randomised trial.

BACKGROUND: The role and dose of anticoagulants in thromboprophylaxis for patients with cancer receiving chemotherapy through central venous catheters (CVCs) is controversial. We therefore assessed whether warfarin reduces catheter-related thrombosis compared with no warfarin and whether the dose of warfarin determines the thromboprophylactic effect. METHODS: In 68 clinical centres in the UK, we randomly assigned 1590 patients aged at least 16 years with cancer who were receiving chemotherapy through CVCs to no warfarin, fixed-dose warfarin 1 mg per day, or dose-adjusted warfarin per day to maintain an international normalised ratio between 1.5 and 2.0. Clinicians who were certain of the benefit of warfarin randomly assigned patients to fixed-dose or dose-adjusted warfarin groups. The primary outcome was the rate of radiologically proven, symptomatic catheter-related thrombosis. Analysis was by intention to treat. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN 50312145. FINDINGS: Compared with no warfarin (n=404), warfarin (n=408; 324 [79%] on fixed-dose and 84 [21%] on dose-adjusted) did not reduce the rate of catheter-related thromboses (24 [6%] vs 24 [6%]; relative risk 0.99, 95% CI 0.57-1.72, p=0.98). However, compared with fixed-dose warfarin (n=471), dose-adjusted warfarin (n=473) was superior in the prevention of catheter-related thromboses (13 [3%] vs 34 [7%]; 0.38, 0.20-0.71, p=0.002). Major bleeding events were rare; an excess was noted with warfarin compared with no warfarin (7 vs 1, p=0.07) and with dose-adjusted warfarin compared with fixed-dose warfarin (16 vs 7, p=0.09). A combined endpoint of thromboses and major bleeding showed no difference between comparisons. We did not note a survival benefit in either comparison. INTERPRETATION: The findings show that prophylactic warfarin compared with no warfarin is not associated with a reduction in symptomatic catheter-related or other thromboses in patients with cancer and therefore we should consider newer treatments. FUNDING: Medical Research Council and Cancer Research UK.

Melanocyte-keratinocyte interaction induces calcium signalling and melanin transfer to keratinocytes.

Physical contact between melanocytes and keratinocytes is a prerequisite for melanosome transfer to occur, but cellular signals induced during or after contact are not fully understood. Herein, it is shown that interactions between melanocyte and keratinocyte plasma membranes induced a transient intracellular calcium signal in keratinocytes that was required for pigment transfer. This intracellular calcium signal occurred due to release of calcium from intracellular stores. Pigment transfer observed in melanocyte-keratinocyte co-cultures was inhibited when intracellular calcium in keratinocytes was chelated. We propose that a 'ligand-receptor' type interaction exists between melanocytes and keratinocytes that triggers intracellular calcium signalling in keratinocytes and mediates melanin transfer.

Effects of paraprotein heavy and light chain types and free light chain load on survival in myeloma: an analysis of patients receiving conventional-dose chemotherapy in Medical Research Council UK multiple myeloma trials.

While investigating 2592 patients enrolled in multicenter myeloma trials, we found light chain-only (LCO) patients had worse median survival times (1.9 years) than patients with IgA and IgG paraproteins (2.3 and 2.5 years, respectively) (P < .001). However, IgA and IgG patients with levels of LC excretion similar to those of LCO patients also had poor survival times because of renal failure, resulting in worse survival during induction therapy and at relapse with no difference in progression-free survival between LCO and IgG patients. LC excretion was higher for lambda than for kappa types, but there was no difference in survival between the 2 LC types when stratified for level of LC excretion, indicating that care of renal function is vital to improving the survival of any patient with LC excretion. LCO patients were younger (P = .001), had worse performance status (P = .001), and had more lytic lesions (P < .001), perhaps reflecting late and missed diagnoses in younger and older LCO patients, respectively. No differences were observed between IgA and IgG patients in presentation characteristics, response, or survival from disease progression. The worse survival of IgA patients was attributed to shorter progression-free survival (median, 1.2 vs 1.6 years; P < .001), which is important for maintenance therapy.

Allogeneic stem-cell transplantation using a reduced-intensity conditioning regimen has the capacity to produce durable remissions and long-term disease-free survival in patients with high-risk acute myeloid leukemia and myelodysplasia.

PURPOSE: The toxicity of allogeneic stem-cell transplantation can be substantially reduced using a reduced-intensity conditioning (RIC) regimen. This has increased the proportion of patients with myeloid malignancies eligible for allogeneic transplantation. However, the capacity of RIC allografts to produce durable remissions in patients with acute myeloid leukemia (AML) and myelodysplasia (MDS) has not yet been defined, and consequently, the role of RIC allografts in the management of these diseases remains conjectural. PATIENTS AND METHODS: Seventy-six patients with high-risk AML or MDS received an allograft using a fludarabine/melphalan RIC regimen incorporating alemtuzumab. The median age of the cohort was 52 years (range, 18 to 71 years). RESULTS: The 100-day transplantation-related mortality rate was 9%, and no patient developed greater than grade 2 graft-versus-host disease. With a median follow-up of 36 months (range, 13 to 70 months), 27 patients were alive and in remission, with 3-year actuarial overall survival (OS) and disease-free survival (DFS) rates of 41% and 37%, respectively. The 3-year OS and DFS rates of patients with AML in complete remission at the time of transplantation were 48% and 42%, respectively. Disease relapse was the most common cause of treatment failure and occurred at a median time of 6 months after transplantation. All but one patient destined to relapse did so within 24 months of transplantation. CONCLUSION: The extended follow-up in this series identifies a high risk of early disease relapse but provides evidence that RIC allografts can produce sustained DFS in a significant number of patients with AML who would be ineligible for allogeneic transplantation with myeloablative conditioning.

Early mortality after diagnosis of multiple myeloma: analysis of patients entered onto the United kingdom Medical Research Council trials between 1980 and 2002--Medical Research Council Adult Leukaemia Working Party.

PURPOSE: Early mortality in multiple myeloma (MM) is usually attributed to combined effects of active disease and comorbid factors. We have studied early deaths in a series of large multicenter trials to assess direct causes of death, their predictability, and whether current management strategies have reduced their frequency. PATIENTS AND METHODS: A total of 3,107 newly diagnosed patients entered onto United Kingdom Medical Research Council MM trials from 1980 to 2002 were studied. Trial files, final clinical summaries, and postmortem reports were analyzed. RESULTS: Death within 60 days of trial entry occurred in 299 patients (10%). Logistic regression modeling identified beta 2-microglobulin, performance status, and age as the most important predictors of early death, but only with 61% sensitivity and 73% specificity. Forty-five percent of deaths were attributable to infection, which was often associated with bone pain (particularly thoracic pain) and delay in presenting to medical care. Neutropenia was present at diagnosis in only 11 of the 135 deaths from infection. Renal failure was present in 28% of early deaths and was linked to light-chain MM, hypercalcemia, dehydration, and nonsteroidal anti-inflammatory drugs. There was no time related reduction in the percentage or nature of early deaths in 1,550 patients older than 65 years receiving similar therapy between 1982 and 2002. CONCLUSION: A tenth of patients die within 60 days of diagnosis of MM. Infection and renal failure are the main direct causes of early mortality, which cannot be accurately predicted by presenting prognostic features. All patients should be considered at high risk of death during induction therapy.

Soluble syndecan-1 level at diagnosis is an independent prognostic factor in multiple myeloma and the extent of fall from diagnosis to plateau predicts for overall survival.

Syndecan-1 (CD138) is a heparin sulphate proteoglycan that is over expressed on the surface of both normal and malignant plasma cells and actively shed from the cell surface (soluble syndecan-1). Soluble syndecan-1 has been shown to be an independent prognostic factor in myeloma but its role in prognostic classification requires further investigation. We have retrospectively measured soluble syndecan-1 in 324 presentation samples and 154 plateau phase samples from the UK Medical Research Council Myeloma VIth trial. Log-rank analysis showed that the presentation value of soluble syndecan-1 is a highly significant prognostic factor when assessing survival from entry (chi2=14.92, P<0.0001) and remains an important independent prognostic factor when considered in Cox regression models (P

Socio-economic deprivation and survival in bladder cancer.

OBJECTIVES: To investigate the relationship between deprivation, delay and survival from bladder cancer in the West Midlands, as socio-economic deprivation is associated with worse survival in many malignancies, and it has been suggested that treatment differences and delay in seeking care are major contributing causes. PATIENTS AND METHODS: Data were prospectively collected on 1537 newly diagnosed cases of urothelial cancer presenting in the West Midlands between January 1991 and June 1992. Survival was censored at 31 July 2000, when 785 (51%) patients had died. The influence of deprivation on survival was explored using cause-specific and all-cause mortality. RESULTS: Patients in less affluent groups had significantly worse survival than patients in more affluent groups when considering deaths from all causes (P = 0.02), which held true when adjusting for independent prognostic factors (age, smoking history, and tumour grade, stage, type and size). Bladder cancer-specific mortality showed no significant difference between socio-economic groups (P = 0.30). CONCLUSION: Socio-economic deprivation is a significant predictor of survival when death from all causes is considered. However, this does not hold true for bladder cancer-specific death. The perceived differences in treatment and delay between socio-economic groups do not seem to occur for bladder cancer in the West Midlands.

Chronic graft-versus-host disease is associated with increased numbers of peripheral blood CD4+CD25high regulatory T cells.

Chronic graft-versus-host disease (cGVHD) is characterized by a state of profound immunodeficiency in association with alloreactive and autoimmune phenomena. These observations indicate an impairment of immunologic tolerance that could involve both central and peripheral mechanisms. Defective thymic function may contribute to dysregulation of central tolerance, but few studies have addressed peripheral tolerance. Recently a population of CD4+CD25+ T cells (Treg cells) has been characterized, which controls immunologic reactivity in vivo and which on transfer can prevent experimental acute GVHD. We investigated the number and function of peripheral blood CD4+CD25high T cells in patients more than 100 days after allogeneic hematopoietic stem cell transplantation. Patients with cGVHD had markedly elevated numbers of CD4+CD25high T cells as compared to patients without GVHD. CD4+CD25high T cells derived from patients in both groups were of donor origin, lacked markers of recent activation, and expressed intracellular CD152. In contrast to controls, CD4+CD25high T cells derived from patients with cGVHD were characterized by lower surface CD62L expression. In vitro, CD4+CD25high T cells were hyporesponsive to polyclonal stimulation and suppressed the proliferation and cytokine synthesis of CD4+CD25- cells, an effect that was independent of interleukin 10. These results indicate that chronic graft-versus-host injury does not occur as a result of Treg cell deficiency.