Nuclear YB-1 expression as a negative prognostic marker in nonsmall cell lung cancer

The human Y-box binding protein, YB-1, is a multifunctional protein that regulates gene expression. Nuclear expression of YB-1 has been associated with chemoresistance and poor prognosis of tumour patients. Representative samples from autopsied material of primary tumours from 77 patients with NSCLC were investigated by immunohistochemistry for subcellular distribution of YB-1 and p53, in order to evaluate the prognostic role of nuclear expression of YB-1. Cytoplasmic YB-1 expression was found in all tumour samples, whereas nuclear expression was only observed in 48%. There was no correlation with histological classification, clinical parameters or tumour size, stage and metastasis status. However, patients with positive nuclear YB-1 expression in tumours showed reduced survival times when compared with patients without nuclear expression. Including information about the histology and mutational status for p53 increased the prognostic value of nuclear YB-1. Patients with nuclear YB-1 expression and p53 mutations had the worst prognosis (median survival 3 months), while best outcome was found in patients with no nuclear YB-1 and wildtype p53 (median survival 15 months). This suggests that the combined analysis of both markers allows a better identification of subgroups with varying prognosis. Nuclear expression of Y-box binding protien seems to be an independent prognostic marker.

Coexpression of p21(WAF1/CIP1) in adenovirus vector transfected human primary hepatocytes prevents apoptosis resulting in improved transgene expression

Replication-deficient adenovirus (Ad vector) is one of the most effective gene transfer systems. However, its employment in human gene therapy trials is hampered by Ad vector associated cytotoxicity and induction of apoptosis of the infected cells. Here, we identify one underlying mechanism as uncoupling of S phase and mitosis of the cell cycle leading to apoptosis and decline of transgene expression. Moreover, we demonstrate a strategy to avoid Ad vector associated cytotoxicity and induction of apoptosis in human primary hepatocytes by coinfection of Ad vector carrying the cDNA of choice and the cell cycle regulator p21(WAF1/CIP1) (p21). In addition, animal experiments were performed using Ad vector directed coexpression of p21 and human alpha 1-antitrypsin. As serum analysis of alpha 1-antitrypsin after Ad vector mediated gene transfer to the liver of mice revealed, this strategy resulted also in the improvement of transgene expression by two orders of magnitude. These data suggest that coexpression of p21 and Ad vector carrying a therapeutic gene may be a promising strategy to avoid cytotoxicity and induction of apoptosis leading to improved safety in human gene therapy.

[Smoking and preoperative fasting--are there evidence-based guidelines?]

Over the last years several clinical studies have modified the guidelines for preoperative fasting to reduce the risk of pulmonary aspiration. In most western countries the following guidelines are accepted: for clear liquids 2 hours, breast feeding 4 hours, small meals and breast milk substitutes 6 hours, heavy meals 8 hours. Since preoperative smoking is acknowledged as a risk factor, it should be ceased in most clinics 6 hours before induction of anaesthesia, as well. Smoking, however, does not increase the risk of pulmonary aspiration, as is often maintained, but increases the risk of postoperative pulmonary complications. To reduce the risk of perioperative pulmonary complications, cessation of smoking is necessary 8 weeks before operation. Stopping smoking only a few days before operation and anaesthesia even tends to increase the risk of pulmonary complications. Regarding cardiac complications, cessation of smoking 12 hours before anaesthesia is sufficient to reduce the incidence of cardiac ischaemia.

Increased levels of markers of vascular inflammation in patients with coronary heart disease

Elevated levels of soluble cell adhesion molecules (sCAMs), inflammatory cytokines and C-reactive protein (CRP) have been associated with atherosclerotic disease states. The aim of the present study was to evaluate whether circulating levels of vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), E- and P-selectin were significantly elevated in patients with coronary heart disease (CHD) compared with healthy controls, and to study possible associations between these sCAMs, tumour necrosis factor alpha (TNFalpha). interleukin-6 (IL-6), CRP and major CHD risk factors. The study included 193 patients in various stages of CHD and 193 matched controls. To evaluate any possible influence of acute phase reaction, reinvestigation was performed after 6 months. After adjustment for major CHD risk factors, sVCAM-1, sICAM-1, P-selectin, IL-6 and CRP remained significantly elevated in the CHD patients (p for all <0.001). In multivariate analysis sVCAM-1 was predicted by age (p=0.015), sICAM-1 by smoking (p<0.001) and total cholesterol (p=0.026), E-selectin by body mass index (BMI) (p=0.004) and P-selectin by male gender (p=0.015). TNFalpha significantly predicted sICAM-1 and E-selectin levels, while IL-6 predicted CRP but none of the sCAMs measured. This might indicate that TNFalpha, but not IL-6, plays a major role in the regulation of sCAM levels in vivo.

Does infection with Chlamydia pneumoniae and/or Helicobacter pylori increase the expression of endothelial cell adhesion molecules in humans?

OBJECTIVE

To investigate if Chlamydia pneumoniae and/or Helicobacter pylori seropositivity is associated with elevated levels of soluble endothelial cell adhesion molecules (sCAMs) as markers of atherosclerotic activity.

METHODS

Immunoglobulin A (IgA) and IgG antibodies to the two bacteria, soluble intercellular cell adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin were measured in coronary heart disease (CHD) patients (n = 193) and age- and sex-matched controls (n = 193). Two different serological methods were used for the detection of Chlamydia antibodies: Labsystems microimmunofluorescence to detect species-specific C. pneumoniae antibodies and Medac's recombinant enzyme-linked immunosorbent assay to detect genus-specific lipopolysaccharide antibodies.

RESULTS

The concentrations of sICAM-1 and E-selectin were higher in CHD patients with positive vs. negative Chlamydia lipopolysaccharide IgA (P = 0.044 for both). H. pylori antibodies alone did not predict raised levels of sCAMs, but in CHD patients sICAM-1 was increased with IgA seropositivity to both bacteria compared to double seronegativity (P = 0.034). Concentrations of sVCAM-1 were elevated in CHD patients with double IgA seropositivity compared to those with Chlamydia lipopolysaccharide IgA seropositivity alone (P = 0.018).

CONCLUSION

Our results may indicate that C. pneumoniae contributes to increased inflammation in CHD, and that this contribution is even more pronounced when present in combination with H. pylori IgA antibodies.

Adenovirus-mediated E2F-1 gene transfer in nonsmall-cell lung cancer induces cell growth arrest and apoptosis

Since overexpression of E2F-1 has been shown to induce apoptosis, the ability of adenovirus-mediated transfer of E2F-1 to inhibit tumour growth in nonsmall-cell lung cancer cell lines was investigated. Three cell lines with various genomic status were infected with AdE2F. Cell proliferation and viability were determined by trypan blue exclusion. Apoptosis induction was assessed by flow cytometry and poly-adenosine diphosphate-ribose-polymerase cleavage assay. In vivo, the effect of E2F-1 on tumour growth was determined in severe combined immunodeficiency (SCID) mice. The current experiments showed that overexpression of E2F-1 suppressed tumour cell growth. The population of apoptotic cells was dramatically increased 96 h after infection with AdE2F. Inhibition of cell growth and induction of apoptosis was not dependent on genomic status. Moreover, treatment of implanted tumours in SCID mice with AdE2F inhibited tumour growth. These data suggest that adenovirus-mediated E2F-1 gene therapy may be effective in the treatment of nonsmall-cell lung cancer.

Positive Chlamydia pneumoniae serology is associated with elevated levels of tumor necrosis factor alpha in patients with coronary heart disease

Infectious agents are possible stimulators of inflammation in atherogenesis. The aim of this study was to investigate if Chlamydia pneumoniae and Helicobacter pylori were associated with elevated levels of tumor necrosis factor alpha (TNFalpha) and interleukin-6 in coronary heart disease (CHD) patients (n=193) and age- and sex-matched controls (n=193) as markers of increased inflammatory activity. C reactive protein (CRP) and fibrinogen were also included. Serologic status towards the two bacteria was measured and levels of the inflammatory markers were compared between seropositives and seronegatives, each study group being evaluated separately. In CHD patients Chlamydia lipopolysaccharide (LPS) IgA seropositivity predicted elevated TNFalpha levels (P=0.009), still statistically significant after adjustment for traditional cardiovascular risk factors (P=0.005). Chlamydia LPS IgG seropositivity independently predicted fibrinogen levels in CHD patients (P=0.028), while no association between serology and inflammatory markers were observed among controls. H. pylori seropositivity alone was not associated with any increase in the inflammatory markers in any of the two groups. However, in CHD patients seropositivity to both agents predicted higher levels of TNFalpha (P=0.041), CRP (P=0.037) and fibrinogen (P=0.001) compared to double seronegativity. We conclude that C. pneumoniae LPS seropositivity may contribute to increased vascular inflammation in CHD patients, possibly even more pronounced when present in combination with H. pylori seropositivity.

[Posttraumatic stress disorder in cancer patients]

BACKGROUND

Patients' response to experiencing a life-threatening disease such as cancer is usually marked by high levels of distress. As the latest modification of the stress criterion for posttraumatic stress disorder includes cancer as a potential precipitating traumatic event, the concept of posttraumatic stress disorder has been widely applied to cancer survivors.

CURRENT RESEARCH

An increasing number of studies try to assess the traumatic impact of the disease on patients' psychological well-being. The prevalence of posttraumatic stress disorder in cancer patients is still not known, mainly due to various methodological problems and the lack of valid assessment instruments.

CONCLUSIONS

The importance of giving clinical attention to the specific stress symptoms in cancer survivors cannot be emphasized enough. Understanding the psychological distress of this population will help clinicians to identify patients at risk and prevent severe stress reactions.

A rodent model of alcoholic heart muscle disease and its evaluation by echocardiography

BACKGROUND

Transthoracic echocardiography was used in a rodent animal model to determine whether long-term alcohol consumption (8 and 12 months) was associated with the development of a dilated cardiomyopathy. We also investigated whether alcohol-induced changes in cardiac structure corresponded to activation of the renin-angiotensin system and the natriuretic peptide (NP) system.

METHODS

Male rats received either the Lieber-DeCarli liquid alcohol diet (EtOH) (9%v/v) (n = 8) or control diet (CON) (n = 8). Echocardiography (echo) was used to determine left-ventricular (LV) dimensions, and isolated heart studies (Langendorff and atrium) were used to assess ex vivo contractility. Plasma and tissue angiotensin-I converting enzyme (ACE) activity was measured. Gene expression, plasma, and tissue levels of the NPs were determined by northern blot analysis and radioimmunoassay, respectively.

RESULTS

After 8 months of alcohol consumption, there was a trend for the end diastolic dimension, end systolic dimension, and LV mass to be greater in the 8 month EtOH group compared with the CON group. However, after 12 months of alcohol consumption, significant increases were found between the groups in several echo parameters. Tissue ACE activity (nmoles/min/mg protein) was greater in the 12 month EtOH group compared with the 12 month CON and 8 month EtOH group (p < 0.05). We found no differences between groups in gene expression (messenger RNA), plasma, and tissue levels of the NPs.

CONCLUSIONS

Echocardiography revealed that 8 to 12 months of alcohol consumption was associated with the development of a dilated cardiomyopathy. However, this was not preceded by an increase in tissue ACE activity, and these changes occurred in the absence of increased plasma and LV tissue levels of the NPs.

Chlamydia pneumoniae serology: importance of methodology in patients with coronary heart disease and healthy individuals

Most publications on the relationship between infection with Chlamydia pneumoniae and coronary heart disease (CHD) propose an association, but negative studies are also reported. Seroepidemiological studies vary in the use of different serological methods, different cutoff limits, different sampling times in relation to acute cardiac events, and different clinical stages of CHD. We wanted to compare three different commercially available methods for measuring Chlamydia antibodies to see how the choice of method influenced the prevalence of seropositive individuals in CHD patients and in healthy individuals and to see if sampling time in relation to an acute cardiac event or the stage of atherothrombotic disease influenced the results. Blood samples from 197 CHD patients and 197 individually matched healthy control individuals were tested at baseline and after 6 months; the mean age was 55 years in both groups, and 18% were women. Among the CHD patients, 166 were included at a median of 16 days after an acute cardiac event and 31 had chronic disease with the latest acute event being >3 months earlier. The difference in prevalence of antibodies between the CHD patients and the healthy controls was significant when Chlamydia lipopolysaccharide antibodies were measured, while no significant differences between the study groups were observed by the two methods detecting Chlamydia pneumoniae major outer membrane protein antibodies. The number of seropositive individuals was quite similar at inclusion and 6 months later, and no significant differences were observed between patients with a recent cardiac event and those with a more remote cardiac event. We conclude that the choice of serological method is of major importance when evaluating a possible relationship between C. pneumoniae and CHD.

Epigenetic and genotype-specific effects on the stability of de novo imposed methylation patterns in transgenic mice

The chloramphenicol acetyltransferase gene under the control of the late E2A promoter of adenovirus type 2 (Ad2) was introduced as transgene into the B6D2F1 mouse strain with mixed genetic background and became extensively de novo methylated. The methylation of this pAd2E2AL-CAT (7-1A) transgene was regulated in a strain-specific manner apparently depending on the site of integration. Transmission of the 7-1A transgene into an inbred DBA/2, 129/sv, or FVB/N genetic background led to a significant loss of methylation in the transgene, whereas C57BL/6, CB20, and Balb/c backgrounds favored the de novo methylation in very specific patterns. The newly established patterns of de novo methylation were transmitted to the offspring and remained stable for many generations, regardless of the heterozygosity of strain-specific DNA sequences present in these mouse strains. Segregation analyses showed a non-mendelian transmission of methylation phenotypes and suggested the involvement of dominant modifiers of methylation. The genotype-specific modifications of the transgene were followed for 11 backcross generations. These observations reflect an evolutionarily conserved mechanism directed against foreign, e.g. viral or bacterial, DNA at least in the chromosomal location of the 7-1A transgene. In seven additional mouse lines carrying the same transgene in different chromosomal locations, strain-specific alterations of methylation patterns were not observed.

Mouse homolog of the Drosophila Pc-G gene esc exerts a dominant negative effect in Drosophila

The Polycomb group genes are involved in maintaining long term transcriptional repression of the homeotic genes in both Drosophila and mammals. The mouse eed locus encodes the highly conserved ortholog of the Drosophila ESC protein. To test the functional conservation between the two genes, eed was introduced into the fly to determine whether it could rescue the esc mutant phenotype. eed exerted a dominant negative effect on the leg transformation phenotype associated with the esc mutation. This result is interpreted in light of in vitro protein-protein binding data and in vivo polytene chromosome staining indicating the lack of significant interaction between Eed and fly E(Z), a molecular partner of ESC. genesis 26:67-76, 2000

Functional antagonism of the Polycomb-Group genes eed and Bmi1 in hemopoietic cell proliferation

The murine Polycomb-Group (PcG) proteins Eed and Bmi1 govern axial patterning during embryonic development by segment-specific repression of Hox gene expression. The two proteins engage in distinct multimeric complexes that are thought to use a common molecular mechanism to render the regulatory regions of Hox and other downstream target genes inaccessible to transcriptional activators. Beyond axial patterning, Bmi1 is also involved in hemopoiesis because a loss-of-function allele causes a profound decrease in bone marrow progenitor cells. Here, evidence is presented that is consistent with an antagonistic function of eed and Bmi1 in hemopoietic cell proliferation. Heterozygosity for an eed null allele causes marked myelo- and lymphoproliferative defects, indicating that eed is involved in the negative regulation of the pool size of lymphoid and myeloid progenitor cells. This antiproliferative function of eed does not appear to be mediated by Hox genes or the tumor suppressor locus p16(INK4a)/p19(ARF) because expression of these genes was not altered in eed mutants. Intercross experiments between eed and Bmi1 mutant mice revealed that Bmi1 is epistatic to eed in the control of primitive bone marrow cell proliferation. However, the genetic interaction between the two genes is cell-type specific as the presence of one or two mutant alleles of eed trans-complements the Bmi1-deficiency in pre-B bone marrow cells. These studies thus suggest that hemopoietic cell proliferation is regulated by the relative contribution of repressive (Eed-containing) and enhancing (Bmi1-containing) PcG gene complexes.