The role of histone demethylases in cancer therapy

Reversible histone methylation has emerged in the last few years as an important mechanism of epigenetic regulation. Histone methyltransferases and demethylases have been identified as contributing factors in the development of several diseases, especially cancer. Therefore, they have been postulated to be new drug targets with high therapeutic potential. Here, we review histone demethylases with a special focus on their potential role in oncology drug discovery. We present an overview over the different classes of enzymes, their biochemistry, selected data on their role in physiology and already available inhibitors.     

Declining Coronary Heart Disease Mortality in Iceland: Contribution by Incidence,Recurrence and Case Fatality Rate

Objective : To analyse to what extent the recent decline in coronary heart disease mortality in Iceland is due to changes in incidence, recurrence and case fatality rates. Design : A countrywide registration of myocardial infarction (MI) in people aged 25-74 was performed in Iceland during 1981-1999 according to the MONICA protocol. Possible cases were found by review of all hospital discharge records, autopsy records and death certificates. Results : MI death rate declined by 63% in males and 51% in females, most in the youngest age groups in men (86%) and least in the oldest (49%). In women there was not a significant difference in age groups. Overall the age-adjusted reduction in MI death rate was 55.4% in both sexes combined; of this 23.1% was due to incidence reduction, 22.8% to recurrence reduction and 11.6% to case fatality reduction. In the youngest age groups the decline in incidence contributed most to the decline in MI death rate (62% in men and 71% in women), but thereafter the decline in case fatality in men. In the older age groups decline in recurrence rate has greater weight. Conclusion : The recent decline in MI mortality under the age of 75 years in Iceland is due to reduction in incidence and recurrence rate by about 40% each and to reduction in case fatality by 20%.     

Optimizing Glioblastoma Temozolomide Chemotherapy Employing Lentiviral-based Anti-MGMT shRNA Technology

Despite treatments combining surgery, radiation-, and chemotherapy, patients affected by glioblastoma (GBM) have a limited prognosis. Addition of temozolomide (TMZ) to radiation therapy is the standard therapy in clinical application, but effectiveness of TMZ is limited by the tumor''s overexpression of the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT). The goal of this study was to use the highly specific and efficient RNA interference (RNAi) pathway to modulate MGMT expression to increase TMZ efficiency in chemotherapy resistant GBM. Using lentiviral-based anti-MGMT small hairpin RNA (shRNA) technology we observed a specific inhibition of the MGMT expression in GBM cell lines as well as in subcutaneous tumors. Tumor growth inhibition was observed following TMZ treatment of xenografts with low MGMT expression in contrast to xenografts with high MGMT expression. Bioluminescence imaging (BLI) measurements indicated that luciferase and shRNA-expressing lentiviruses were able to efficiently transduce the GBM xenografts in vivo. Treatment combining injection of a lentivirus expressing an anti-MGMT shRNA and TMZ induced a reduction of the size of the tumors, in contrast with treatment combining the lentivirus expressing the control shRNA and TMZ. Our data suggest that anti-MGMT shRNA therapy could be used in combination with TMZ chemotherapy in order to improve the treatment of resistant GBM.     

Upper respiratory tract infections in general practice: diagnosis,antibiotic prescribing,duration of symptoms and use of diagnostic tests

A diagnosis/antibiotic prescribing study was performed in 5 counties in Sweden for 1 week in November 2000. As part of this study, the characteristics and clinical management of patients with upper respiratory tract infections (n = 2899) in primary care were analyzed. Almost half of the patients were aged < 15 y and one-fifth of the patients consulted out of hours. Of all patients seeking primary care for upper respiratory tract infections, 56.0% were prescribed an antibiotic. Almost all patients who were given the diagnoses streptococcal tonsillitis, acute otitis media or acute sinusitis were prescribed antibiotics, compared to 10% of patients with common cold or acute pharyngitis. The most frequently prescribed antibiotic was penicillin V (79.2%) and this was even more pronounced out of hours, when the diagnoses otitis media and streptococcal tonsillitis were more frequently used. In patients with common cold and acute pharyngitis, the percentage who received antibiotics increased with increasing length of symptoms and increasing CRP levels. In patients with acute pharyngitis or streptococcal tonsillitis, antibiotics were prescribed less frequently provided streptococcal tests were performed. The management of patients with upper respiratory tract infections in general practice seems to be in good agreement with current Swedish guidelines. However, the study indicates some areas for improvement. The diagnosis of acute sinusitis seems to have been overestimated and used only to justify antibiotic treatment.     

Neuroendocrine responses to stress in mice: hyporesponsiveness in pregnancy and parturition

Hypothalamo-pituitary-adrenal axis secretory responses to stress were compared in female virgin, late pregnant, parturient, and lactating mice. The basal plasma ACTH concentration was not different in pregnancy or lactation compared with virgins, but corticosterone concentration and corticosteroid-binding globulin capacity were greatly elevated in late pregnancy. Secretory responses to novel environment were attenuated in pregnant, but not lactating, mice compared with virgin females, whereas ACTH responses to forced swimming were attenuated in both groups. The expression of immediate early gene (nur77) mRNA increased in paraventricular nucleus neurons after stress exposure in virgin and lactating, but not pregnant, mice. During parturition, the basal ACTH concentration was similar to virgin and pregnant controls and did not increase with stress. Oxytocin secretion in response to either novel environment or forced swimming was unchanged in any reproductive group, whereas vasopressin secretion was decreased by both stressors, but only in virgins. Pretreatment with oxytocin receptor antagonist centrally had no effect on ACTH responses to stress in either virgin or pregnant mice. Pretreatment with an opioid receptor antagonist increased ACTH responses to stress in virgin mice, indicating opioid inhibition, but had no effect in pregnancy. Thus, in mice hypothalamo-pituitary-adrenal hyporesponsiveness in late pregnancy is a consequence of reduced responsiveness of paraventricular neurons, but inhibition by opioids or intracerebral oxytocin does not appear to be involved.     

Variation in estrogen-related genes and cross-sectional and longitudinal blood pressure in the Framingham Heart Study

OBJECTIVE: To examine the association between variation in estrogen-related genes and cross-sectional and longitudinal blood pressure in men and women. DESIGN: In 1780 unrelated members of the community-based Framingham Heart Study offspring cohort, systolic blood pressure and diastolic blood pressure were measured over a total of six examination cycles encompassing 24 years of follow-up. Multivariate regression analyses were used to assess the relation between untreated cross-sectional and longitudinal blood pressure and polymorphisms at the estrogen receptor-alpha (ESR1), estrogen receptor-beta (ESR2), aromatase (CYP19A1), and nuclear receptor coactivator 1 (NCOA1) genes after adjustment for common risk factors. RESULTS: In men, systolic blood pressure and pulse pressure (systolic blood pressure minus diastolic blood pressure) were associated with two polymorphisms in ESR1, while pulse pressure was also associated with variations in NCOA1 and CYP19A1. Polymorphisms in ESR1, CYP19A1, and NCOA1 were associated with diastolic blood pressure in women. CONCLUSIONS: Although the underlying relations between genes involved in estrogen action and hypertension remain to be completely understood, our findings provide suggestive evidence of gender-specific contributions of estrogen-related genes to blood pressure variation. As no correction for multiple testing was performed in the analyses, we view these results as suggestive and not definitive. Further studies are warranted to confirm these results using a comprehensive set of polymorphisms in order to shed more light on the involvement of estrogen in blood pressure regulation.     

Amount of systemic steroid medication is a strong predictor for the use of complementary and alternative medicine in patients with inflammatory bowel disease: results from a German national survey

OBJECTIVES: Previous studies have suggested that inflammatory bowel disease (IBD) patients rank high among users of complementary and alternative medicine (CAM). To further elucidate this phenomenon, we sent questionnaires to a large sample of IBD patients in Germany to determine the patterns and predictors of their CAM use. METHODS: Pretested 73-item questionnaires were mailed to a randomly selected representative sample of 1000 IBD patients from the approximately 16,000 members and associates of the German Crohn's and Colitis Association. Predictors of CAM use were evaluated by logistic regression models. RESULTS: Completed questionnaires were returned by 684 patients (female patients, 61.4%; Crohn's disease patients, 58.3%; ulcerative colitis patients, 38.2%). Of the 671 adult respondents, 344 (51.3%) had experience with CAM, and significantly more of the ulcerative colitis patients (59.8%) than the Crohn's disease patients (48.3%) had experience with CAM. There was no difference by gender. Homeopathy (52.9%) and herbal medicine (43.6%) were the most commonly used types of CAM. The most frequent personal reasons for CAM use were the search for an "optimum treatment" (78.9%) and the wish to stop taking steroids (63.8%). Using logistic regression, we found that total cortisone intake (P = 0.0077), but not duration of disease, was a strong predictor of CAM use. Other predictors were experience with psychosomatic and psychotherapeutic support (P = 0.0029), relaxation techniques (P = 0.0284), an academic education (P = 0.0173), a diet utilizing whole grains (P = 0.0123), and a normal body weight (P = 0.0215). Although 80% of patients indicated that they were interested in using CAM in the future, only 24.7% felt sufficiently informed about it. CONCLUSIONS: More than 50% of a large group of German IBD patients had used CAM. Prolonged or intensive steroid treatment, an academic education, active ways of coping, and a health-conscious life-style are associated with CAM use. Given the potential side effects and interactions, the treating physician should focus on thorough information about the benefits and limitations of conventional and complementary treatment options, especially for IBD patients who have received prolonged or intensive steroid treatment.