Altered expression of beta1 integrins in renal carcinoma cell lines exposed to the differentiation inducer valproic acid

Renal cell carcinoma (RCC) is the most common malignant tumor of the kidney. Adhesion receptors of the beta1 integrin family are assumed to be involved in carcinogenesis, but it is not clear how they contribute to RCC progression. In an in vitro model, we evaluated growth and adhesion capacity of Caki-I and KTC-26 kidney carcinoma cell lines compared to normal renal proximal tubular epithelial cells (PTC). alpha1-alpha6beta1 integrin subunits in malignant and non-malignant cells were evaluated by Western blotting and RT-PCR, integrin surface expression was measured by flow cytometry and confocal microscopy. Additionally, tumor cells were allowed to re-differentiate in the presence of valproic acid (VPA) and dynamic alterations of the integrin profile were analyzed. Caki-I and KTC-26 were characterized by accelerated proliferation and adhesion to an endothelial cell monolayer, compared to PTC cells. The integrin beta1 repertoire in RCC cell lines was significantly different from that detected in PTC, and included down-regulated alpha2 and alpha6, but up-regulated alpha1, alpha3 and alpha5 proteins. VPA application reduced tumor malignancy which was evidenced by reduced cell growth and adhesion capacity. The reduction in tumor malignancy was paralleled by the integrin expression profile of renal tumor cells 'matching' the pattern seen in PTC. We assume that a sensitive integrin balance exists in normal renal epithelial cells, and that dysregulation of the 'physiological' receptor equipment drives these cells towards malignancy. VPA acted on all investigated integrin subtypes and restored the receptor pattern typical for non-malignant cells. Therefore, VPA may represent a novel therapeutic option in RCC treatment.

The HIV protease inhibitor ritonavir synergizes with butyrate for induction of apoptotic cell death and mediates expression of heme oxygenase-1 in DLD-1 colon carcinoma cells

The protease inhibitor ritonavir is an integral part of current antiretroviral therapy targeting human immunodeficiency virus. Recent studies demonstrate that ritonavir induces apoptotic cell death with high efficiency in lymphoblastoid cell lines. Moreover, ritonavir can suppress activation of the transcription factor nuclear factor-kappaB and is an inhibitor of interleukin-1beta and tumor necrosis factor-alpha production in peripheral blood mononuclear cells. Thus, ritonavir appears to have anti-inflammatory properties. In the present study, we investigated in DLD-1 colon carcinoma cell effects of ritonavir on apoptotic cell death and expression of heme oxygenase-1 (HO-1), an anti-inflammatory enzyme that may be critically involved in the modulation of colonic inflammation. Compared to unstimulated control, ritonavir resulted in a moderate increase in the rate of apoptotic cell death as observed after 20 h of incubation. Notably, ritonavir potently synergized with the short-chain fatty acid butyrate for induction of caspase-3-dependent apoptosis in DLD-1 cells. Ritonavir enhanced mRNA and protein expression of HO-1 in DLD-1 cells. Ritonavir-induced HO-1 protein was suppressed by SB203580 or SB202190 and preceded by immediate upregulation of cellular c-Fos and c-Jun protein levels. This process was associated with induction of activator protein-1 as detected by electrophoretic mobility shift analysis. The present data suggest that ritonavir has the potential to curb colon carcinogenesis by reducing cell growth via mechanisms that include apoptosis and by simultaneously modulating colonic inflammation via induction of anti-inflammatory HO-1.

Inhibition of lipopolysaccharide/ATP-induced release of interleukin-18 by KN-62 and glyburide

Monocytes release interleukin-18 after activation by lipopolysaccharide/ATP. Since inflammatory conditions such as sepsis are characterized by augmented interleukin-18 in sera of patients, we sought to modulate lipopolysaccharide/ATP-induced interleukin-18 release by pharmacological means. Here we report that 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine (KN-62), an inhibitor of ATP-mediated cellular activation by the purinoreceptor subtype P(2x7), potently suppresses interleukin-18 release from peripheral blood mononuclear cells. Interleukin-18 liberation was likewise inhibited by glyburide, a modulator of ion transport and inhibitor of ATP-binding cassette transporter 1. The data presented herein indicate that by pharmacologically interfering with the process of cytokine secretion agents such as KN-62 or glyburide have the potential to curb overproduction of interleukin-18 in septic patients.

IL-18BPa:Fc cooperates with immunosuppressive drugs in human whole blood

The proinflammatory cytokine interleukin (IL)-18 appears to be involved in the pathogenesis of diseases associated with immunoactivation and inflammation. Consequently, blockage of IL-18 bioactivity by use of IL-18 binding protein (IL-18 BP) is likely a promising therapeutic concept. In the present study, we investigated immunomodulatory activities of IL-18 BPa:Fc in human whole blood cultures. We report that IL-18 BPa:Fc (200 ng/mL) significantly inhibited lipopolysaccharide (LPS, 10 ng/mL)/IL-12 (5 ng/mL)-induced release of interferon-gamma (IFNgamma) and matrix metalloproteinase-9 (MMP-9) from whole blood cultures of healthy donors. Notably, IL-18 BPa:Fc (200 ng/mL) further reinforced dexamethasone (5 nM)- or mycophenolic acid (2 microM)-mediated reduction of LPS/IL-12-induced IFNgamma production by an additional 50.5 or 49.9%, respectively. To investigate effects of IL-18 BP:Fc in the context of autoimmune diseases, experiments were performed with whole blood obtained from patients with systemic lupus erythematosus or Wegener's granulomatosis undergoing immunosuppressive therapy. After ex vivo stimulation with LPS (10 ng/mL), production of IFNgamma and MMP-9 was determined. Both mediators likely contribute to renal inflammation frequently seen in these diseases. In accord with the aforementioned data, LPS (10 ng/mL)-induced IFNgamma was significantly reduced by coincubation with IL-18 BPa:Fc at 200 ng/mL. IL-18 BPa:Fc also inhibited production of MMP-9. The present data demonstrate that IL-18 BPa:Fc has the potential to amplify anti-inflammatory actions of immunosuppressive drugs, and thus may prove to be a valuable novel pharmacological component in the treatment of human autoimmune diseases.

["Simplified Acute Physiology Score" (SAPS II) ina the assessment of severity of illness in surgical intensive care patients]

INTRODUCTION

In 1993, Le Gall proposed a new Simplified Acute Physiology Score (SAPS II) to assess the severity of illness in intensive care patients and to predict the risk of hospital mortality using a large data base of more than 13,000 patients of different intensive care units. Up to the present time, no satisfactory form of validation for surgical intensive care patients has been available. We investigated the prognostic quality of this score system for the assessment of the severity of the illness in surgical intensive care patients.

METHODS

Between October 1997 and December 1998, 310 consecutive patients were included in our study. We calculated the SAPS II score according to the published guidelines. Additionally, we calculated the risk of mortality by referring to the score. We used a receiver operating characteristics (ROC) analysis for statistical evaluation.

RESULTS

The median duration of stay on our intensive care unit was 8.4 days. In all patients, the mean SAPS II was 29.9 +/- 12.7. In the survivors, calculation of mean SAPS II was 27.7 +/- 11.4. In the non-survivors, mean SAPS II was 45.7 +/- 11.2. The predicted risk of mortality was 15.7%, the actual risk of mortality was 15.8%.

CONCLUSION

The SAPS II score has proved to be a good prognostic instrument in surgical intensive care patients. SAPS II is particularly effective in providing an exact estimation of the risk of death, classifying patient groups in clinical studies, epidemiological investigations, and quality assessment.

L-selectin in trauma patients: a marker for organ dysfunction and outcome?

BACKGROUND

Systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS) are important factors affecting morbidity and mortality after trauma. Adhesion molecules, e.g. L-selectin (CD62 L), play crucial roles in both conditions.

PATIENTS AND METHODS

In 51 multiple trauma patients, CD62 L surface expression on granulocytes, monocytes, lymphocytes, as well as sCD62 L plasma concentrations were determined during the first 6 days after trauma, starting at the site of accident. Clinical parameters were severity of injury scores (ISS, APACHE II), requirement of red blood cell transfusion, acute lung or liver failure, development of MODS or SIRS, early (< or = 6 d) or late (> 6 d), and outcome.

RESULTS

CD62 L expression was reversibly elevated on granulocytes, T cells and monocytes in comparison with initial values. sCD62 L plasma concentrations did not show temporal variations but were depressed throughout observation period, in comparison with healthy controls. Lung failure within the first 6 days was associated with increased CD62 L expression on monocytes and B cells on admission and increased sCD62 L concentrations after 12 and 24 h. Patients with more severe injuries (APACHE II > 20 points) had higher sCD62 L concentrations after 24 h. Non-survivors had decreased sCD62 L (on admission) and T-cell CD62 L expression (after 4 h). Patients with early MODS or SIRS showed increased monocyte CD62 L expression after 6 days.

CONCLUSIONS

In multiple trauma patients, severe organ dysfunction is associated with altered CD62 L expression on leukocytes and circulating sCD62 L plasma concentrations. However, the obvious complexity of the pattern currently restricts use of CD62 L quantitation for clinical purposes.

[Late results of surgical treatment of chronic anterolateral instability of the proximal ankle joint]

In the literature more than 30 methods of syndesmoplastic surgery are described for the treatment of chronic ligament instability in the ankle. The aim of our investigation was, on the basis of long-term results, to determine which surgical method has the least complications, which offers the best chances from the viewpoint of exercise and sports, and whether degenerative changes in the joint can be avoided by restitution of stability. By means of isokinetic testing with 36 patients we were able to determine differences in the long-term results of various surgical methods, viz. syndesmoplasty using the peroneus brevis muscle as modified by Evans and Watson/Jones, respectively, and periosteal syndesmoplasty. In the period from 1980 through 1990, at the Graz Hospital for Trauma Surgery we performed 77 syndesmoplastic operations on 75 patients suffering from chronic ligament instability in the ankle joint. Of these cases, 45 were followed up for 6-136 months after the operation. On the basis of the results of these postoperative examinations we recommend periosteal syndesmoplasty for management of chronic ligament instability in the ankle, as this method is relatively easy to perform, prevents post-traumatic arthrosis, ensures maximum stability, which consequently means a low complication rate, and shows favorable final results in isokinetic testing.