Asbestos-related lung cancer: Clinical characteristics and survival outcomes in an Australian cohort seeking workers compensation.

BACKGROUND AND OBJECTIVES: Due to difficulties in identifying sufficient-sized cohorts there remains uncertainty about prognostic and clinical differences that may be unique to asbestos-related lung cancer (ARLC). In this study, we use the Helsinki Criteria to define a group of ex-workers with lung cancer attributable to asbestos exposure and investigate differences that may exist. METHODS: A total of 529 patients seeking workers' compensation for their lung cancer were assigned to either ARLC or the non-ARLC based on parameters defined in the Helsinki Criteria. Clinical and survival details were collected and analyzed. RESULTS: In our study population, ARLC patients were on average older (72.1 ± 7.8) than non-ARLC patients (66.5 ± 10.2, P < 0.001) and were more likely to be diagnosed as a result of incidental findings or screening program (P < 0.001). The groups were similar in terms of clinical characteristics with the only difference being that plaques were more prevalent among ARLC patients (P < 0.001). Differences were observed for median overall survival (OS), ARLC (9 months) and non-ARLC (13 months, P = 0.005), as well for treatment (P = 0.01). After adjusting for age, however, these differences disappeared. CONCLUSIONS: Age at diagnosis, pleural plaques, and asymptomatic presentation were the attributes that we identified as significantly different between asbestos-related cancer and other lung cancers. In this cohort, ARLC patients were older diagnosis and with worse overall survival.

Changes in Lipids and Inflammatory Markers after Consuming Diets High in Red Meat or Dairy for Four Weeks.

There is a body of evidence linking inflammation, altered lipid metabolism, and insulin resistance. Our previous research found that insulin sensitivity decreased after a four-week diet high in dairy compared to a control diet and to one high in red meat. Our aim was to determine whether a relationship exists between changes in insulin sensitivity and inflammatory biomarkers, or with lipid species. Fasting Tumor Necrosis Factor alpha (TNF-α), Tumor Necrosis Factor Receptor II (sTNF-RII), C-reactive protein (CRP), and lipids were measured at the end of each diet. TNF-α and the ratio TNF-α/sTNF-RII were not different between diets and TNF-α, sTNF-RII, or the ratio TNF-α/sTNF-RII showed no association with homeostasis model assessment-estimated insulin resistance (HOMA-IR). A number of phosphatidylethanolamine (PE) and phosphatidylinositol (PI) species differed between dairy and red meat and dairy and control diets, as did many phosphatidylcholine (PC) species and cholesteryl ester (CE) 14:0, CE15:0, lysophosphatidylcholine (LPC) 14:0, and LPC15:0. None had a significant relationship (p = 0.001 or better) with log homeostasis model assessment-estimated insulin resistance (HOMA-IR), although LPC14:0 had the strongest relationship (p = 0.004) and may be the main mediator of the effect of dairy on insulin sensitivity. LPC14:0 and the whole LPC class were correlated with CRP. The correlations between dietary change and the minor plasma phospholipids PI32:1 and PE32:1 are novel and may reflect significant changes in membrane composition. Inflammatory markers were not altered by changes in protein source while the correlation of LPC with CRP confirms a relationship between changes in lipid profile and inflammation.

Integrin linked kinase (ILK) is required for lens epithelial cell survival, proliferation and differentiation.

While the role of growth factors in lens development has been investigated extensively, the role of extracellular matrix signalling is less well understood. The developing lens expresses predominantly laminin-binding integrins (such as α3ß1, α6ß1), which are cooperatively required in the lens epithelium during development. We investigated the role of ILK, a downstream mediator of integrin signalling in mice conditionally null for Ilk. Mutant lenses showed epithelial thinning at E17.5 with reduced proliferation and epithelial cell number and aberrant fibre differentiation. There was complete loss of the central epithelium from postnatal day (P) 2 due to cell death followed by fibre cell degeneration and death by P10 as well as rupture of the lens capsule between P10 and P21. At E17.5 there was significant inhibition (∼50%) of epithelial cell cycle progression, as shown by BrdU incorporation, cyclin D1/D2 and phospho-histone H3 immunostaining. The epithelial marker, E-cadherin, was decreased progressively from E17.5 to P2, in the central epithelium, but there was no significant change in Pax6 expression. Analyses of ERK and Akt phosphorylation indicated marked depression of MAPK and PI3K-Akt signalling, which correlated with decreased phosphorylation of FRS2α and Shp2, indicating altered activation of FGF receptors. At later postnatal stages there was reduced or delayed expression of fibre cell markers (ß-crystallin and p57(kip2)). Loss of Ilk also affected deposition of extracellular matrix, with marked retention of collagen IV within differentiating fibre cells. By quantitative RT-PCR array there was significantly decreased expression of 19 genes associated with focal adhesions, actin filament stability and MAPK and PI3K/Akt signalling. Overall, these data indicate that ILK is required for complete activation of signalling cascades downstream of the FGF receptor in lens epithelium and fibre cells during development and thus is involved in epithelial proliferation, survival and subsequent fibre differentiation.

Food label education does not reduce sodium intake in people with type 2 diabetes mellitus. A randomised controlled trial.

BACKGROUND: Sodium intake is high in people with type 2 diabetes (T2DM). The aim of this study was to investigate whether urinary sodium excretion can be reduced by educating people with T2DM to read food labels and choose low sodium products. METHOD: In a 3 month randomised controlled trial, 78 men (n=49) and women (n=29) with T2DM were recruited from a Diabetes Centre at a University teaching hospital. The intervention group was educated in a single session to use the nutrition information panel on food labels to choose products which complied with the Food Standards Australia New Zealand (FSANZ) guideline of <120 mg sodium/100 g food. The control group continued on their usual diet. The primary outcome measure was 24h urinary sodium excretion which was performed at baseline and 3 months. Data was analysed using repeated measures analysis of variance, independent samples t-test and Pearson's correlations. RESULTS: At 3 months mean urinary sodium excretion was unchanged in the intervention (174±13 mmol/24 h and 175±13 mmol/24 h) and control group (167±15mmol/24h and 161±13 mmol/24 h), and there was no between group difference (p>0.05). CONCLUSION: Sodium excretion was not reduced following the label reading education provided to this group of people with T2DM.

Conditional mutations of beta-catenin and APC reveal roles for canonical Wnt signaling in lens differentiation.

PURPOSE: Previous studies indicate that the Wnt/beta-catenin-signaling pathway is active and functional during murine lens development. In this study, the consequences of constitutively activating the pathway in lens during development were investigated. METHODS: To activate Wnt/beta-catenin signaling, beta-catenin (Catnb) and adenomatous polyposis coli (Apc) genes were conditionally mutated in two Cre lines that are active in whole lens (MLR10) or only in differentiated fibers (MLR39), from E13.5. Lens phenotype in mutant lenses was investigated by histology, immunohistochemistry, BrdU labeling, quantitative RT-PCR arrays, and TUNEL. RESULTS: Only intercrosses with MLR10 resulted in ocular phenotypes, indicating Wnt/beta-catenin signaling functions in lens epithelium and during early fiber differentiation. Mutant lenses were characterized by increased progression of epithelial cells through the cell cycle, as shown by BrdU labeling, and phosphohistone 3 and cyclin D1 labeling, and maintenance of epithelial phenotype (E-cadherin and Pax6 expression) in the fiber compartment. Fiber cell differentiation was delayed as shown by reduced expression of c-maf and beta-crystallin and delay in expression of the CDKI, p57(kip2). From E13.5, there were numerous cells undergoing apoptosis, and by E15.5, there was evidence of epithelial-mesenchymal transition with numerous cells expressing alpha-smooth muscle actin. Quantitative PCR analyses revealed large changes in expression of Wnt target genes (Lef1, Tcf7, T (Brachyury), and Ccnd1), Wnt inhibitors (Wif1, Dkk1, Nkd1, and Frzb) and also several Wnts (Wnt6, Wnt10a, Wnt8b, and Wnt11). CONCLUSIONS: These data indicate that the Wnt/beta-catenin pathway plays key roles in regulating proliferation of lens stem/progenitor cells during early stages of fiber cell differentiation.

Asbestos-related occupational lung diseases in NSW, Australia and potential exposure of the general population.

Asbestos is a fibrous silicate which is recognized as causing a variety of lung disorders including malignant mesothelioma of the pleura, lung cancer and asbestosis. Asbestos use has been banned in most developed countries but exposure still occurs under strict regulation in occupational settings and also occasionally in domestic settings. Although the hazards of asbestos are well known in developed countries, awareness of its adverse health effects is less in other parts of the world, particularly when exposure occurs in non-occupational settings. Experience of asbestos use and its adverse heath effects in developed countries such as Australia have resulted in development of expertise in the diagnosis and treatment of asbestos-related diseases as well as in screening and this can be used to help developing countries facing the issue of asbestos exposure.

Differential requirement for beta-catenin in epithelial and fiber cells during lens development.

Recent studies implicate Wnt/beta-catenin signaling in lens differentiation (Stump, R. J., et al., 2003. A role for Wnt/beta-catenin signaling in lens epithelial differentiation. Dev Biol;259:48-61). Beta-catenin is a component of adherens junctions and functions as a transcriptional activator in canonical Wnt signaling. We investigated the effects of Cre/LoxP-mediated deletion of beta-catenin during lens development using two Cre lines that specifically deleted beta-catenin in whole lens or only in differentiated fibers, from E13.5. We found that beta-catenin was required in lens epithelium and during early fiber differentiation but appeared to be redundant in differentiated fiber cells. Complete loss of beta-catenin resulted in an abnormal and deficient epithelial layer with loss of E-cadherin and Pax6 expression as well as abnormal expression of c-Maf and p57(kip2) but not Prox1. There was also disrupted fiber cell differentiation, characterized by poor cell elongation, decreased beta-crystallin expression, epithelial cell cycle arrest at G(1)-S transition and premature cell cycle exit. Despite cell cycle arrest there was no induction of apoptosis. Mutant fiber cells displayed altered apical-basal polarity as evidenced by altered distribution of the tight junction protein, ZO1, disruption of apical actin filaments and abnormal deposition of extracellular matrix, resulting in a deficient lens capsule. Loss of beta-catenin also affected the formation of adhesion junctions as evidenced by dissociation of N-cadherin and F-actin localization in differentiating fiber cells. However, loss of beta-catenin from terminally differentiating fibers had no apparent effects on adhesion junctions between adjacent embryonic fibers. These data indicate that beta-catenin plays distinct functions during lens fiber differentiation and is involved in both Wnt signaling and adhesion-related mechanisms that regulate lens epithelium and early fiber differentiation.