Paradoxical roles of tumour necrosis factor-alpha in prostate cancer biology

Tumour necrosis factor (TNF) is a pleiotropic cytokine with dual roles in cancer biology including prostate cancer (PCa). On the one hand, there is evidence that it stimulates tumour angiogenesis, is involved in the initiation of PCa from an androgen-dependent to a castrate resistant state, plays a role in epithelial to mesenchymal plasiticity, and may contribute to the aberrant regulation of eicosanoid pathways. On the other hand, TNF has also been reported to inhibit neovascularisation, induce apoptosis of PCa cells, and stimulate anti-tumour immunity. Much of the confusion surrounding its seemingly paradoxical roles in cancer biology stems from the dependence of its effects on the biological model within which TNF is investigated. This review will address some of these issues, and also discuss on the therapeutic implications.

Tumour necrosis is an independent prognostic marker in non-small cell lung cancer : correlation with biological variables

Background Tumour necrosis (TN) is recognized to be a consequence of chronic cellular hypoxia. TN and hypoxia correlate with poor prognosis in solid tumours. Methods In a retrospective study the prognostic implications of the extent of TN was evaluated in non-small cell lung cancer (NSCLC) and correlated with clinicopathological variables and expression of epidermal growth factor receptor, Bcl-2, p53 and matrix metalloproteinase-9 (MMP-9). Tissue specimens from 178 surgically resected cases of stage I-IIIA NSCLC with curative intent were studied. The specimens were routinely processed, formalin-fixed and paraffin-embedded. TN was graded as extensive or either limited or absent by two independent observers; disagreements were resolved using a double-headed microscope. The degree of reproducibility was estimated by re-interpreting 40 randomly selected cases after a 4 month interval. Results Reproducibility was attained in 36/40 cases, Kappa score=0.8 P<0.001. TN correlated with T-stage (P=0.001), platelet count (P=0.004) and p53 expression (P=0.031). Near significant associations of TN with N-stage (P=0.063) and MMP-9 expression (P=0.058) were seen. No association was found with angiogenesis (P=0.98). On univariate (P=0.0016) and multivariate analysis (P=0.023) TN was prognostic. Conclusion These results indicate that extensive TN reflects an aggressive tumour phenotype in NSCLC and may improve the predictive power of the TMN staging system. The lack of association between TN and angiogenesis may be important although these variables were not evaluated on serial sections. © 2002 Elsevier Science Ireland Ltd. All rights reserved.

The chromosome 16q region associated with ankylosing spondylitis includes the candidate gene tumour necrosis factor receptor type 1-associated death domain (TRADD)

Objective: To replicate and refine the reported association of ankylosing spondylitis (AS) with two nonsynonymous single nucleotide polymorphisms (nsSNPs) on chromosome 16q22.1. Methods: Firstly, 730 independent UK patients with AS were genotyped for rs9939768 and rs6979 and allele frequencies were compared with 2879 previously typed historic disease controls. Secondly, the two data sets were combined in meta-analyses. Finally, 5 tagging SNPs, located between rs9939768 and rs6979, were analysed in 1604 cases and 1020 controls. Results: The association of rs6979 with AS was replicated, p=0.03, OR=1.14 (95% CI 1.01 to 1.28), and a trend for association with rs9939768 detected, p=0.06, OR=1.25 (95% CI 0.99 to 1.57). Meta-analyses revealed association of both SNPs with AS, p=0.0008, OR=1.31 (95% CI 1.12 to 1.54) and p=0.0009, OR=1.15 (95% CI 1.06 to 1.23) for rs9939768 and rs6979, respectively. New associations with rs9033 and rs868213 (p=0.00002, OR=1.23 (95% CI 1.12 to 1.36) and p=0.00002 OR=1.45 (95% CI 1.22 to 1.72), respectively, were identified. Conclusions: The region on chromosome 16 that has been replicated in the present work is interesting as the highly plausible candidate gene, tumour necrosis factor receptor type 1 (TNFR1)-associated death domain (TRADD), is located between rs9033 and rs868213. It will require additional work to identify the primary genetic association(s) with AS.

Evidence of genetic association between TNFRSF1A encoding the p55 tumour necrosis factor receptor, and ankylosing spondylitis in UK Caucasians

Objectives: To replicate the possible genetic association between ankylosing spondylitis (AS) and TNFRSF1A. Methods: TNFRSF1A was re-sequenced in 48 individuals with AS to identify novel polymorphisms. Nine single nucleotide polymorphisms (SNPs) in TNFRSF1A and 5 SNPs in the neighbouring gene SCNN1A were genotyped in 1604 UK Caucasian individuals with AS and 1019 matched controls. An extended study was implemented using additional genotype data on 8 of these SNPs from 1400 historical controls from the 1958 British Birth Cohort. A meta-analysis of previously published results was also undertaken. Results: One novel variant in intron 6 was identified but no new coding variants. No definite associations were seen in the initial study but in the extended study there were weak associations with rs4149576 (p=0.04) and rs4149577 (p=0.007). In the metaanalysis consistent, somewhat stronger associations were seen with rs4149577 (p=0.002) and rs4149578 (p=0.006). Conclusions: These studies confirm the weak genetic associations between AS and TNFRSF1A. In view of the previously reported associations of TNFRSF1A with AS, in Caucasians and Chinese, and the biological plausibility of this candidate gene, replication of this finding in well powered studies is clearly indicated.

Australian data do not support current pharmaceutical benefits scheme criteria for use of tumour necrosis factor-α inhibitors in ankylosing spondylitis

On the basis of local data, we write in support of the conclusions of Smith and Ahern that current Pharmaceu- tical Benefits Scheme (PBS) criteria for tumour necrosis factor (TNF)-a inhibitors in ankylosing spondylitis (AS) are not evidence-based. 1 As a prerequisite to the appropriate use of biological therapy in AS, three aspects of the disease need to be defined: (i) diagnosis, (ii) activity and (iii) therapeutic failure (Table 1)....

Genetic variation in tumour necrosis factor and lymphotoxin is not associated with endometriosis in an Australian sample

BACKGROUND Tumour necrosis factor (TNF) is a pleiotropic cytokine with a wide range of immunoregulatory effects. Variation in the promoter region of TNF and the neighbouring lymphotoxin alpha (LTA) gene might be associated with endometriosis. METHODS We examined the association between endometriosis and common single-nucleotide polymorphisms (SNPs) or haplotypes in the TNF/LTA region in an Australian sample by analysing 26 SNPs in 958 endometriosis cases and 959 unrelated controls. We selected functional SNPs in the coding and the promoter region of the TNF gene and HapMap tagging SNPs and typed them on a Sequenom MassARRAY platform. A key SNP (rs1800630) in the promoter region typed in previous studies did not give reliable results. Therefore, we also examined a statistically identical (r(2) = 1) SNP (siSNP) (rs2844482), identified using the web based program ssSNPer. RESULTS Genotype completion rate was 99.5% for SNPs spanning a region of 15.5 kb across the TNF/LTA locus. There was no evidence for association between endometriosis and TNF/LTA SNPs or SNP haplotypes in our case-control study. CONCLUSIONS Our data suggest both TNF and LTA genes are not major susceptibility genes for endometriosis.

Preliminary characterisation of tumor necrosis factor alpha and interleukin-10 responses to chlamydia pecorum infection in the koala (Phascolarctos cinereus)

Debilitating infectious diseases caused by Chlamydia are major contributors to the decline of Australia's iconic native marsupial species, the koala (Phascolarctos cinereus). An understanding of koala chlamydial disease pathogenesis and the development of effective strategies to control infections continue to be hindered by an almost complete lack of species-specific immunological reagents. The cell-mediated immune response has been shown to play an influential role in the response to chlamydial infection in other hosts. The objective of this study, hence, was to provide preliminary data on the role of two key cytokines, pro-inflammatory tumour necrosis factor alpha (TNFα) and anti-inflammatory interleukin 10 (IL10), in the koala Chlamydia pecorum response. Utilising sequence homology between the cytokine sequences obtained from several recently sequenced marsupial genomes, this report describes the first mRNA sequences of any koala cytokine and the development of koala specific TNFα and IL10 real-time PCR assays to measure the expression of these genes from koala samples. In preliminary studies comparing wild koalas with overt chlamydial disease, previous evidence of C. pecorum infection or no signs of C. pecorum infection, we revealed strong but variable expression of TNFα and IL10 in wild koalas with current signs of chlamydiosis. The description of these assays and the preliminary data on the cell-mediated immune response of koalas to chlamydial infection paves the way for future studies characterising the koala immune response to a range of its pathogens while providing reagents to assist with measuring the efficacy of ongoing attempts to develop a koala chlamydial vaccine.

Elevated concentration of TNF-a induces trophoblast differentiation in mouse blastocyst outgrowths

Elevated expression of tumour necrosis factora (TNF-a) is associated with adverse pregnancy outcome. This study has examined the expression of TNF-a and its receptors (TNF-Rs) by mouse blastocysts and blastocyst outgrowths from day 4 to 9.5 of pregnancy and investigated the effects of elevated TNF-a on the inner cell mass (ICM) and trophoblast cells of blastocyst outgrowths. RTPCR demonstrated TNF-a mRNA expression from day 7.5 to 9.5, TNF-R1 from day 6.5 to 9.5 and TNF-R2 from day 5.5 to 7.5 of pregnancy, and in situ hybridisation revealed the trophoblast giant cells (TGCs) of the early placenta as the site of TNF-a expression. Day 4 blastocysts were cultured in a physiologically high concentration of TNF-a (100 ng/ml) for 72 h to the outgrowth stage and then compared to blastocysts cultured in media alone. TNF-a-treated blastocyst outgrowths exhibited a significant reduction in ICM cells (mean € SD 23.90€10.42 vs 9.37€7.45, t-test, P<0.0001) with no significant change in the numbers of trophoblast cells (19.97€8.14 vs 21.73€7.79, t-test, P=0.39). Within the trophoblast cell population, the TNF-a-treated outgrowths exhibited a significant increase in multinucleated cells (14.10€5.53 vs 6.37€5.80, t-test, P<0.0001) and a corresponding significant decrease in mononucleated cells (5.87€3.60 vs 15.37€5.87, t-test, P<0.0001). In summary, this study describes the expression of TNF-a and its receptors during the peri-implantation period in the mouse. It also reports that elevated TNF-a restricts ICM proliferation in the blastocyst and changes the ratio of mononucleated to multinucleated trophoblast cells. These findings suggest a mechanism by which increased

Body temperature and its effect on leukocyte mobilization, cytokines and markers of neutrophil activation during and after exercise

We investigated the influence of rectal temperature on the immune system during and after exercise. Ten well-trained male cyclists completed exercise trials (90 min cycling at 60% VO(2max) + 16.1 - km time trial) on three separate occasions: once in 18 degrees C and twice in 32 degrees C. Twenty minutes after the trials in 32 degrees C, the cyclists sat for approximately 20 min in cold water (14 degrees C) on one occasion, whereas on another occasion they sat at room temperature. Rectal temperature increased significantly during cycling in both conditions, and was significantly higher after cycling in 32 degrees C than in 18 degrees C (P < 0.05). Leukocyte counts increased significantly during cycling but did not differ between the conditions. The concentrations of serum interleukin (IL)-6, IL-8 and IL-10, plasma catecholamines, granulocyte-colony stimulating factor, myeloperoxidase and calprotectin increased significantly following cycling in both conditions. The concentrations of serum IL-8 (25%), IL-10 (120%), IL-1 receptor antagonist (70%), tumour necrosis factor-alpha (17%), plasma myeloperoxidase (26%) and norepinephrine (130%) were significantly higher after cycling in 32 degrees C than in 18 degrees C. During recovery from exercise in 32 degrees C, rectal temperature was significantly lower in response to sitting in cold water than at room temperature. However, immune changes during 90 min of recovery did not differ significantly between sitting in cold water and at room temperature. The greater rise in rectal temperature during exercise in 32 degrees C increased the concentrations of serum IL-8, IL-10, IL-1ra, TNF-alpha and plasma myeloperoxidase, whereas the greater decline in rectal temperature during cold water immersion after exercise did not affect immune responses.

Changes in markers of muscle damage, inflammation and HSP70 after an Ironman triathlon race

We investigated the effects of an Ironman triathlon race on markers of muscle damage, inflammation and heat shock protein 70 (HSP70). Nine well-trained male triathletes (mean +/- SD age 34 +/- 5 years; VO(2peak) 66.4 ml kg(-1) min(-1)) participated in the 2004 Western Australia Ironman triathlon race (3.8 km swim, 180 km cycle, 42.2 km run). We assessed jump height, muscle strength and soreness, and collected venous blood samples 2 days before the race, within 30 min and 14-20 h after the race. Plasma samples were analysed for muscle proteins, acute phase proteins, cytokines, heat shock protein 70 (HSP70), and clinical biochemical variables related to dehydration, haemolysis, liver and renal functions. Muscular strength and jump height decreased significantly (P < 0.05) after the race, whereas muscle soreness and the plasma concentrations of muscle proteins increased. The cytokines interleukin (IL)-1 receptor antagonist, IL-6 and IL-10, and HSP70 increased markedly after the race, while IL-12p40 and granulocyte colony-stimulating factor (G-CSF) were also elevated. IL-4, IL-1beta and tumour necrosis factor-alpha did not change significantly, despite elevated C-reactive protein and serum amyloid protein A on the day after the race. Plasma creatinine, uric acid and total bilirubin concentrations and gamma-glutamyl transferase activity also changed after the race. In conclusion, despite evidence of muscle damage and an acute phase response after the race, the pro-inflammatory cytokine response was minimal and anti-inflammatory cytokines were induced. HSP70 is released into the circulation as a function of exercise duration.

Investigation of lymphotoxin α genetic variants in migraine

Migraine is a common neurological disease with a genetic basis affecting approximately 12% of the population. Pain during a migraine attack is associated with activation of the trigeminal nerve system, which carries pain signals from the meninges and the blood vessels infusing the meninges to the trigeminal nucleus in the brain stem. The release of inflammatory mediators following cortical spreading depression (CSD) may further promote and sustain the activation and sensitization of meningeal nociceptors, inducing the persistent throbbing headache characterised in migraine. Lymphotoxin α (LTA) is a cytokine secreted by lymphocytes and is a member of the tumour necrosis factor (TNF) family. Genetic variation with the TNF and LTA genes may contribute to threshold brain excitability, propagation of neuronal hyperexcitability and thus initiation and maintenance of a migraine attack. Three LTA variants rs2009658, rs2844482 and rs2229094 were identified in a recent pGWAS study conducted in the Norfolk Island population as being potentially implicated in migraine with nominally significant p values of p = 0.0093, p = 0.0088 and p = 0.033 respectively. To determine whether these SNPs played a role in migraine in a general outbred population these SNPs were gentoyped in a large case control Australian Caucasian population and tested for association with migraine. All three SNPs showed no association in our cohort (p > 0.05). Validation of GWAS data in independent case-controls cohorts is essential to establish risk validity within specific population groups. The importance of cytokines in modulating neural inflammation and pain threshold in addition to other studies showing associations between TNF-α and SNPs in the LTA gene with migraine, suggests that LTA could be an important factor contributing to migraine. Although the present study did not support a role for the tested LTA variants in migraine, investigation of other variants within the LTA gene is still warranted.

Immunodeficiency-associated lymphomas

This article covers lymphoproliferative disorders in patients with primary or acquired immunodeficiencies. Primary immunodeficiences include Ataxia Telangiectasia and X-linked disorders such as Wiskott-Aldrich syndrome. Acquired immunodeficiencies predominantly occur in the setting of infection with the Human Immunodeficiency Virus or arise following immunosuppressive therapy administered after organ transplantation. The rising incidence of HIV throughout the world and the dramatic increase in transplant surgery since the 1990's suggest that these lymphomas will remain an important health problem. Evidence for lymphoma developing as a result of treatment with methotrexate or Tumour Necrosis Factor Antagonists for autoimmune entities will also be reviewed. The lymphoproliferations that occur with immunodeficiency are extremely heterogenous. In part this reflects the diversity of the causal immune defect. The most striking clinical characteristic is the high frequency of extranodal disease. Frequently, these lymphomas are driven by viruses such as Epstein-Barr virus (EBV), although the lack of EBV in a proportion indicates that alternate pathways must also be involved in the pathogenesis. Lastly, discussion will centre on mechanisms utilized by lymphomas in the immunodeficient as these may have applications to lymphomas in the "immunocompetent", by serving as a paradigm for the altered immunoregulatory environment present in many lymphoma sub-types.

Postprandial total and HMW adiponectin following a high-fat meal in lean, obese and diabetic men

BACKGROUND/OBJECTIVES: Recent work suggests that macronutrients are pro-inflammatory and promote oxidative stress. Reports of postprandial regulation of total adiponectin have been mixed, and there is limited information regarding postprandial changes in high molecular weight (HMW) adiponectin. The aim of this study was to assess the effect of a standardised high-fat meal on metabolic variables, adiponectin (total and HMW), and markers of inflammation and oxidative stress in: (i) lean, (ii) obese non-diabetic and (iii) men with type 2 diabetes mellitus (T2DM). SUBJECTS/METHODS: Male subjects: lean (n=10), obese (n=10) and T2DM (n=10) were studied for 6 h following both a high-fat meal and water control. Metabolic variables (glucose, insulin, triglycerides), inflammatory markers (interleukin-6 (IL6), tumour necrosis factor (TNF)α, high-sensitivity C-reactive protein (hsCRP), nuclear factor (NF)κB expression in peripheral blood mononuclear cells (p65)), indicators of oxidative stress (oxidised low density lipoprotein (oxLDL), protein carbonyl) and adiponectin (total and HMW) were measured. RESULTS: No significant changes in TNFα, p65, oxLDL or protein carbonyl concentrations were observed. Overall, postprandial IL6 decreased in subjects with T2DM but increased in lean subjects, whereas hsCRP decreased in the lean cohort and increased in obese subjects. There was no overall postprandial change in total or HMW adiponectin in any group. Total adiponectin concentrations changed over time following the water control, and the response was significantly different in lean subjects compared with subjects with T2DM (P=0.04). CONCLUSIONS: No consistent significant postprandial inflammation, oxidative stress or regulation of adiponectin was observed in this study. Findings from the water control suggest differential basal regulation of total adiponectin in T2DM compared with lean controls.

Clinico-pathological and biological prognostic factors in pleural malignant mesothelioma

In the UK mortality from malignant mesothelioma (MM) is likely to more than double over the next 20 years and despite advances in surgery, chemotherapy and radiation treatment the overall prognosis for patients remains poor. A number of scoring systems based on assessment of clinicopathological features of patients with the disease have been developed but the search continues for further prognostic indicators. Angiogenesis, tumour necrosis (TN), epidermal growth factor receptor (EGFR) expression, cyclooxygenase-2 (COX-2) and matrix metalloproteinases (MMPs) have been linked with poor prognosis in some types of solid tumour and their relevance as prognostic factors in malignant mesothelioma is examined in this paper. © 2004 Elsevier Ireland Ltd. All rights reserved.

Epidermal growth factor receptors and cyclooxygenase-2 in the pathogenesis of non-small cell lung cancer : potential targets for chemoprevention and systemic therapy

The epidermal growth factor receptor (EGFR) is part of a family of plasma membrane receptor tyrosine kinases that control many important cellular functions, from growth and proliferation to cell death. Cyclooxygenase (COX)-2 is an enzyme which catalyses the conversion of arachidonic acid to prostagladins and thromboxane. It is induced by various inflammatory stimuli, including the pro-inflammatory cytokines, Interleukin (IL)-1β, Tumour Necrosis Factor (TNF)-α and IL-2. Both EGFR and COX-2 are over-expressed in non-small cell lung cancer (NSCLC) and have been implicated in the early stages of tumourigenesis. This paper considers their roles in the development and progression of lung cancer, their potential interactions, and reviews the recent progress in cancer therapies that are directed toward these targets. An increasing body of evidence suggests that selective inhibitors of both EGFR and COX-2 are potential therapeutic agents for the treatment of NSCLC, in the adjuvant, metastatic and chemopreventative settings. © 2002 Elsevier Science Ireland Ltd. All rights reserved.