Cyclin D1 and p16 expression in pleomorphic adenoma and carcinoma ex pleomorphic adenoma of the parotid gland

AIMS

To compare cyclin D1 and p16(ink4) (p16) expression in normal tissue, pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma (CXPA) of the parotid gland.

METHODS AND RESULTS

Immunohistochemistry was used to examine cyclin D1 and p16 expression in 43 parotid tumours (29 PAs and 14 CXPAs). Cyclin D1 and p16 were both significantly more likely to be expressed in the neoplastic than in the normal epithelial and stromal components of PA and CXPA (P < 0.001 and P < 0.005, respectively). Cyclin D1 was more likely to be expressed in the malignant components of CXPA than in the benign components of PA (50% versus 31% and 31%, respectively), but the trend was not statistically significant. There was no evidence of this association for p16 (corresponding positivity rates 69% versus 81% and 52%).

CONCLUSIONS

Our findings provide preliminary evidence of roles for cyclin D1 and p16 in the development of PA and for cyclin D1 in the progression of PA to CXPA.

Immune-mediated activation of the endocannabinoid system in visceral adipose tissue in obesity

The aim of the study was to investigate if the endocannabinoid system (ECS) is activated in visceral adipose tissue and if adipose tissue inflammation affects the ECS activation state. Therefore, expression of fatty acid amide hydrolase (FAAH), cannabinoid receptor 1 (Cb1), adiponectin, and tumor necrosis factor (TNF)-alpha was compared in visceral adipose tissue from 10 normal-weight (BMI 24.4+/-1.1 kg/m2) and 11 obese subjects (BMI 37.6+/-13.6 kg/m2) using quantitative RT-PCR, and gene expression changes were analyzed after in vitro stimulation of visceral adipose tissue with TNF-alpha. The data demonstrate that the ECS is activated in obese visceral adipose tissue as shown by decreased FAAH, Cb1, and adiponectin expression. Obesity-related ECS activation is accompanied by elevated expression of the pro-inflammatory cytokine TNF-alpha, which in turn stimulates ECS activation in vitro. Our data show a strong association between adipose tissue inflammation and ECS activation in obesity, and indicate that a pro-inflammatory state may directly activate the ECS.

Cyclin A expression and its diagnostic value in pleomorphic adenoma and carcinoma expleomorphic adenoma of the parotid gland

AIMS

To investigate cyclin A expression in pleomorphic adenoma (PA) and carcinoma expleomorphic adenoma (CXPA) of the parotid gland with a view to assessing its potential value as a diagnostic marker for CXPA.

METHODS AND RESULTS

Cyclin A expression in PA and CXPA was studied using semiquantitative immunohistochemistry. The epithelial component of the tumours expressed cyclin A in a statistically significantly (P < 0.005) higher number of CXPA cases (86%) compared with the PA cases (39%). Cyclin A was not expressed in normal salivary tissues of PA and CXPA.

CONCLUSIONS

High cyclin A expression is a useful marker for the pathological diagnosis of CXPA.

Longitudinal-transverse separations of deep-inelastic structure functions at low Q2 for hydrogen and deuterium

We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06<Q2<2.8 GeV2. Even at the lowest values of Q2, R remains nearly constant and does not disappear with decreasing Q2, as might be expected. We find a nearly identical behavior for hydrogen and deuterium.

The metabolic syndrome sensitizes leukocytes for glucose-induced immune gene expression

Definitions of the metabolic syndrome (MetS) include obesity, dyslipidemia, elevated levels of fasting blood glucose, and blood pressure as criteria, but it is also known that the MetS is associated with chronic, subclinical inflammation. Hyperglycemia (fasting and postprandial) may be important in exacerbating this proinflammatory state. We aimed to assess the impact of oral glucose challenge and in vitro glucose-stimulation on gene expression and secretion of inflammatory parameters in peripheral blood leukocytes and to investigate whether presence of the MetS could "prime" leukocytes to up-regulate proinflammatory markers in response to glucose. Using quantitative real-time PCR, we could show that the expression of intercellular adhesion molecule 1 (ICAM-1), tumor necrosis factor alpha (TNF-alpha), and interleukin 6 (IL-6) significantly increased in peripheral blood leukocytes from "MetS" subjects (n=39) compared to "no MetS" subjects (n=35) 2 h after an oral glucose tolerance test (ICAM-1 +52%, TNF-alpha +107%, and IL-6 +38%) and also in vitro after 72 h cultivation in high-glucose medium (ICAM-1 +74%, TNF-alpha +71%, and IL-6 +44%). Using ELISA and Luminex technique, we further observed a trend towards increased immune mediator concentrations in the corresponding cell culture supernatants from MetS patients (ICAM-1 +21%, TNF-alpha +31%, and IL-6 +175%). Thus, the MetS may support peripheral inflammation by sensitizing leukocytes to up-regulate proinflammatory markers in response to glucose, which in turn increases the risk for type-2 diabetes mellitus and cardiovascular disease.

Dose-dependent induction of IL-6 by plant-derived proteases in vitro

Oral administration of proteases such as bromelain and papain is commonly used in patients with a wide range of inflammatory conditions, but their molecular and cellular mechanisms of action are still poorly understood. The aim of our study was to investigate the impact of these proteases on the release of interleukin-6 (IL-6) and other cytokines in the recently described modified mixed lymphocyte culture (MMLC) test system which is based on the mutual interaction of cells of the innate and adaptive immunity. Bromelain and papain enhanced IL-6 production dose-dependently up to 400-fold in MMLC before and up to 30-fold after neutralization of LPS content of proteases using polymyxin B, indicating that IL-6 induction by protease treatment was attributable to both protease action and LPS content of enzyme preparations. The production of IFNgamma and IL-10 was not altered by bromelain or papain, indicating a selective and differential immune activation. Both proteases impaired cytokine stability, cell proliferation and expression of cell surface molecules like CD14 only marginally, suggesting no impact of these mechanisms on protease-mediated cytokine release. These findings might provide the mechanistic rationale for the current use of proteases in wound healing and tissue regeneration since these processes depend on IL-6 induction.

High prevalence of undiagnosed impaired glucose regulation and diabetes mellitus in patients scheduled for an elective coronary angiography

BACKGROUND

Impaired glucose regulation (IGR) and diabetes mellitus (DM) are amongst the main risk factors for developing coronary heart disease (CHD). The aim of this study was to investigate previously unknown glucose metabolism disorder in patients scheduled for an elective coronary angiography.

METHODS

A total of 141 patients scheduled for coronary angiography without signs of acute myocardial ischemia or previous history of a glucose metabolism disorder were prospectively included in the study. An oral glucose tolerance test (OGTT) was performed in each patient.

RESULTS

IGR was diagnosed in 40.4% (95% confidence interval 32.3-49.0) and undetected DM in 22.7% (16.1-30.5) of patients undergoing an elective coronary angiography. Depending on the severity of CHD, the percentage of IGR and DM increased up to 45.3% (34.6-56.5) and 26.7% (17.8-37.4) in the subgroup with the need of percutaneous angioplasty, while the corresponding proportions in the group without CHD were 30.3% (15.6-48.7) and 12.1% (3.4-28.2). The percentage of undiagnosed DM increased with the number of epicardial vessels involved. Using the recommended fasting plasma glucose value of > or = 126 mg/dl for the diagnosis of DM, we would have missed 71.9% of the patients with undiagnosed DM. If all patients with a fasting plasma glucose of > or = 90 mg/dl had been subjected to OGTT, 93.8% of DM would have been identified.

CONCLUSIONS

Prevalences of DM and IGR are higher than expected in patients with CHD. An OGTT should be considered for all patients with a fasting plasma glucose > or = 90 mg/dl undergoing a coronary angiography.