Impact of Malic Enzymes on Antibiotic and Triacylglycerol Production in Streptomyces coelicolor

In this paper, we have characterized two malic enzymes (ME), SCO2951 and SCO5261, from Streptomyces coelicolor and analyzed their role in antibiotic and triacylglycerol (TAG) production. Biochemical studies have demonstrated that Sco2951 and Sco5261 genes encode NAD(+)- and NADP(+)-dependent malic enzymes, respectively. Single or double mutants in the ME-encoding genes show no effect on growth rate compared to the parental M145 strain. However, the single Sco2951 and the double Sco2951 Sco5261 mutants display a strong reduction in the production of the polyketide antibiotic actinorhodin; additionally, the Sco2951 Sco5261 mutant shows a decrease in stored TAGs during exponential growth. The lower production of actinorhodin in the double mutant occurs as a consequence of a decrease in the expression of actII-ORF4, the transcriptional activator of the actinorhodin gene cluster. On the other hand, the reduced TAG accumulation is not due to reduced transcript levels of fatty acid biosynthetic genes nor to changes in the amount of the precursor acetyl coenzyme A (acetyl-CoA). This mutant accumulates intermediates of the tricarboxylic acid (TCA) cycle that could alter the regulation of the actinorhodin biosynthetic pathway, suggesting that MEs are important anaplerotic enzymes that redirect C4 intermediates from the TCA cycle to maintain secondary metabolism and TAG production in Streptomyces

Hepatocellular carcinoma: Trends of incidence and survival in Europe and the United States at the end of the 20th century

OBJECTIVES: There is large geographic variation in incidence levels and time trends of hepatocellular carcinoma. We compared population-based liver cancer incidence and survival in European and U.S. populations in order to elucidate geographic differences and time trends for these variables. METHODS: Since comparisons based on cancer registry data are problematic because of variations in liver cancer definition and coding, we considered a subset of cases likely to be mainly hepatocellular carcinoma, suitable for international comparison. Incidence and 5-yr relative survival were calculated from cases diagnosed in five European regions (30,423 cases) and the United States (6,976 cases) in 1982-1994. RESULTS: Age-standardized incidence was highest in southern Europe (12/100,000 in men and 3/100,000 in women in 1992-94) and lowest in northern Europe, where incidence was similar to that of the United States (3/100,000 in men, <1/100,000 in women). Over the study period, incidence remained stable in the United States and most of Europe, except for a notable increase in southern Europe. Five-year relative survival was <10% in Europe, ranging from 8% (southern Europe) to 5% (eastern Europe), and 6% in the United States. Survival increased slightly with time, mainly in southern Europe and was unaffected by sex, but was better in younger patients. CONCLUSIONS: Increasing incidence in southern Europe is probably related to hepatitis B and C infection and increasing alcohol intake, while improving survival may be due to greater surveillance for cirrhosis. The survival gap between clinical and population-based series suggests management is better in centers of excellence. © 2007 by Am. Coll. of Gastroenterology

Childhood cancer survival in Europe.

BACKGROUND: EUROCARE-3 collected data from 45 population-based cancer registries in 20 countries on 24 620 European children aged from 0 to 14 years diagnosed with malignancy in the period 1990-1994. METHODS: Five-year survival between countries was compared for all malignancies and for the major diagnostic categories, adjusting for age, and estimated average European survival weighting for differences in childhood populations. RESULTS: For all cancers combined, survival variation was large (45% in Estonia to 90% in Iceland), and was generally low (60-70%) in eastern Europe and high (> or =75%) in Switzerland, Germany and the Nordic countries (except Denmark). The Nordic countries had the highest survival for four of the seven major tumour types: nephroblastoma (92%), acute lymphoid leukaemia (85%), CNS tumours (73%) and acute non-lymphocytic leukaemia (62%). The eastern countries had lowest survival: 89% for Hodgkin's disease, 71% for nephroblastoma, 68% for acute lymphoid leukaemia, 61% for non-Hodgkin's lymphoma, 57% for central nervous system (CNS) tumours and 29% for acute non-lymphocytic leukaemia. CONCLUSIONS: The Nordic countries represent a survival gold standard to which other countries can aspire. Since most childhood cancers respond well to treatment, survival differences are attributable to differences in access (including referral and timely diagnosis) and use of modern treatments; however, the obstacles to access and application of standard treatments probably vary markedly with country

Influence of morphology on survival for non-Hodgkin lymphoma in Europe and the United States

We explored the influence of morphology on geographic differences in 5-year survival for non-Hodgkin lymphoma (NHL) diagnosed in 1990-1994 and followed for 5 years: 16,955 cases from 27 EUROCARE-3 cancer registries, and 22,713 cases from 9 US SEER registries. Overall 5-year relative survival was 56.1% in EUROCARE west, 47.1% in EUROCARE east and 56.3% in SEER. Relative excess risk (RER) of death was 1.05 (95% confidence interval (CI) 1.01-1.10) in EUROCARE west, 1.52 (95% CI 1.44-1.60) in EUROCARE east (SEER reference). Excess risk of death was significantly above reference (diffuse B lymphoma) for Burkitt's and NOS lymphoma; not different for lymphoblastic and other T-cell; significantly below reference (in the order of decreasing relative excess risk) for NHL NOS, mantle cell/centrocytic, lymphoplasmacytic, follicular, small lymphocytic/chronic lymphocytic leukaemia, other specified NHL and cutaneous morphologies. Interpretation of marked variation in survival with morphology is complicated by classification inconsistencies. The completeness and standardisation of cancer registry morphology data needs to be improved

Survival from rare cancer in adults: A population-based study

Backround: Rare cancers are a challenge to clinical practice, and treatment experience, even in major cancer centres to which rare cancers are usually referred, is often limited. We aimed to study the epidemiology of rare cancers in a large population of several countries. Methods: We analysed survival by age, sex, subsite, and morphology in 57 144 adults with 14 selected rare cancers diagnosed 1983-94. Variations in survival over time and between European regions were also assessed for variations in quality of care. We also estimated the adjusted relative excess risk of death for every rare cancer. Findings: Overall 5 -year relative survival was good (ie, >65%) for placental choriocarcinoma (85.4% [95% CI 81.4-89.5]), thyroid medullary carcinoma (72.4% [69.2-75.5]), ovarian germ-cell cancer (73.0% [70.0-76.0]), lung carcinoid (70.1% [67.3-72.9]), and cervical adenocarcinoma (65.5% [64.3-66.6]); intermediate (ie, 35-65%) for testicular cancer at age 65 years or older (64.0% [59.3-68.7]), sarcoma of extremities (60.0% [58.9-61.2]), digestive-system endocrine cancers (55.6% [54.9-56.3]), anal squamous-cell carcinoma (53.1% [51.5-54.8]), and uterine sarcoma (43.5% [42.0-44.9]); low for carcinoma of adrenal-gland cortex (32.7% [28.3-37.2]) and bladder squamous-cell carcinoma (20.4% [18.8-22.0]); and poor for angiosarcoma of liver (6.4% [1.8-11.0]) and mesothelioma (4.7% [4.3-5.2]). Survival was usually better for women than men and poor in those aged 75 years or older. Survival significantly improved over time for ovarian germ-cell cancer, sarcomas of extremities, digestive-system endocrine tumours, anal squamous-cell carcinoma, and angiosarcoma of liver. Survival in northern Europe was higher than in the other geographic groupings for most cancers. Interpretation: Because effective treatments are available for several of the rare cancers we assessed, further research is needed to ascertain why survival is lower in some European countries than in others, particularly in older patients. Audit of best practice for rare cancers with treatment protocols would be useful