{"title":"Asymmetric organocatalysis on a technical scale: current status and future challenges.","authors":"H Gröger","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 2","pages":"141-58"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27547537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N-Heterocyclic carbenes (NHC) have become an important class of organocatalysts and class of ligands for transition-metal catalysis. In organocatalyzed umpolung reactions, thiazolium salt-derived NHC have been used successfully for decades. Even so, during recent years there has been an increased interest in NHC-catalyzed transformations and many new reactions have been developed. This article focuses on the use of NHC in the conjugate umpolung of alpha,beta-unsaturated aldehydes.
{"title":"Nucleophilic carbenes as organocatalysts.","authors":"F Glorius, K Hirano","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>N-Heterocyclic carbenes (NHC) have become an important class of organocatalysts and class of ligands for transition-metal catalysis. In organocatalyzed umpolung reactions, thiazolium salt-derived NHC have been used successfully for decades. Even so, during recent years there has been an increased interest in NHC-catalyzed transformations and many new reactions have been developed. This article focuses on the use of NHC in the conjugate umpolung of alpha,beta-unsaturated aldehydes.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 2","pages":"159-81"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27547538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metabolic stress is an important stimulus that promotes apoptosis-mediated tumor suppression. Metabolic stress arises in tumors from multiple factors that include insufficient nutrient supply caused by deficient angiogenesis and high metabolic demand of unrestrained cell proliferation. The high metabolic demand of tumor cells is only exacerbated by reliance on the inefficient process of glycolysis for energy production. Recently it has become clear that tumor cells survive metabolic stress through the catabolic process of autophagy. Autophagy also functions as a tumor suppression mechanism by preventing cell death and inflammation and by protecting the genome from damage and genetic instability. How autophagy protects the genome is not yet clear but may be related to its roles in sustaining metabolism or in the clearance of damaged proteins and organelles and the mitigation of oxidative stress. These findings illuminate the important role of metabolism in cancer progression and provide specific predictions for metabolic modulation in cancer therapy.
{"title":"Role of the metabolic stress responses of apoptosis and autophagy in tumor suppression.","authors":"E White","doi":"10.1007/2789_2008_087","DOIUrl":"https://doi.org/10.1007/2789_2008_087","url":null,"abstract":"<p><p>Metabolic stress is an important stimulus that promotes apoptosis-mediated tumor suppression. Metabolic stress arises in tumors from multiple factors that include insufficient nutrient supply caused by deficient angiogenesis and high metabolic demand of unrestrained cell proliferation. The high metabolic demand of tumor cells is only exacerbated by reliance on the inefficient process of glycolysis for energy production. Recently it has become clear that tumor cells survive metabolic stress through the catabolic process of autophagy. Autophagy also functions as a tumor suppression mechanism by preventing cell death and inflammation and by protecting the genome from damage and genetic instability. How autophagy protects the genome is not yet clear but may be related to its roles in sustaining metabolism or in the clearance of damaged proteins and organelles and the mitigation of oxidative stress. These findings illuminate the important role of metabolism in cancer progression and provide specific predictions for metabolic modulation in cancer therapy.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 4","pages":"23-34"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2008_087","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27690206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For several solid human malignancies, currently available serum biomarkers are insufficiently reliable to distinguish patients from healthy individuals. Metabonomics, the study of metabolic processes in biologic systems, is based on the use of 1H-NMR spectroscopy and multivariate statistics for biochemical data generation and interpretation and may provide a characteristic fingerprint in disease. Here we review our initial experiences utilizing the metabonomic approach for discriminating sera from women with epithelial ovarian cancer (EOC) from healthy controls. 1H-NMR spectroscopic analysis was performed on preoperative serum specimens of 38 EOC patients, 12 patients with benign ovarian cysts and 53 healthy women. PCA analysis allowed correct separation of all serum specimens from 38 patients with EOC (100%) from all of the 21 premenopausal normal samples (100%) and from all the sera from patients with benign ovarian disease (100%). In addition, it was possible to correctly separate 37 of 38 (97.4%) cancer specimens from 31 of 32 (97%) postmenopausal control sera. ROC analysis indicated that the sera from patients with and without disease could be identified with 100% sensitivity and specificity at the 1H-NMR regions 2.77 parts per million (ppm) and 2.04 ppm from the origin (AUC of ROC curve = 1.0). These findings indicate that the 1H-NMR metabonomic approach deserves further evaluation as a potential novel strategy for the early detection of EOC.
{"title":"Cancer diagnostics using 1H-NMR-based metabonomics.","authors":"K Odunsi","doi":"10.1007/2789_2008_095","DOIUrl":"https://doi.org/10.1007/2789_2008_095","url":null,"abstract":"<p><p>For several solid human malignancies, currently available serum biomarkers are insufficiently reliable to distinguish patients from healthy individuals. Metabonomics, the study of metabolic processes in biologic systems, is based on the use of 1H-NMR spectroscopy and multivariate statistics for biochemical data generation and interpretation and may provide a characteristic fingerprint in disease. Here we review our initial experiences utilizing the metabonomic approach for discriminating sera from women with epithelial ovarian cancer (EOC) from healthy controls. 1H-NMR spectroscopic analysis was performed on preoperative serum specimens of 38 EOC patients, 12 patients with benign ovarian cysts and 53 healthy women. PCA analysis allowed correct separation of all serum specimens from 38 patients with EOC (100%) from all of the 21 premenopausal normal samples (100%) and from all the sera from patients with benign ovarian disease (100%). In addition, it was possible to correctly separate 37 of 38 (97.4%) cancer specimens from 31 of 32 (97%) postmenopausal control sera. ROC analysis indicated that the sera from patients with and without disease could be identified with 100% sensitivity and specificity at the 1H-NMR regions 2.77 parts per million (ppm) and 2.04 ppm from the origin (AUC of ROC curve = 1.0). These findings indicate that the 1H-NMR metabonomic approach deserves further evaluation as a potential novel strategy for the early detection of EOC.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 4","pages":"205-26"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2008_095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27691254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A major charter for modern nutrition is to provide a molecular basis for health outcome resulting from different food choices and how this could be designed to maintain individual health free of disease. Nutrigenomic techniques have been developed to generate information at various levels of biological organization, i.e. genes, proteins, and metabolites. Within this frame, metabonomics targets the molecular characterization of a living system through metabolic profiling. The metabolic profiles are explored with sophisticated data mining techniques mainly based on multivariate statistics, which can recover key metabolic information to be further linked to biochemical processes and physiological events. The power of metabonomics relies on its unique ability to assess functional changes in the metabolism of complex organisms stemming from multiple influences such as lifestyle and environmental factors. In particular, metabolic profiles encapsulate information on the metabolic activity of symbiotic partners, i.e. gut microflora, in complex organisms, which represent major determinant in nutrition and health. Therefore, applications of metabonomics to nutrition sciences led to the nutrimetabonomics approach for the classification of dietary responses in populations and the possibility of optimized or personalized nutritional management.
{"title":"Defining personal nutrition and metabolic health through metabonomics.","authors":"S Rezzi, F-P J Martin, S Kochhar","doi":"10.1007/2789_2008_097","DOIUrl":"https://doi.org/10.1007/2789_2008_097","url":null,"abstract":"<p><p>A major charter for modern nutrition is to provide a molecular basis for health outcome resulting from different food choices and how this could be designed to maintain individual health free of disease. Nutrigenomic techniques have been developed to generate information at various levels of biological organization, i.e. genes, proteins, and metabolites. Within this frame, metabonomics targets the molecular characterization of a living system through metabolic profiling. The metabolic profiles are explored with sophisticated data mining techniques mainly based on multivariate statistics, which can recover key metabolic information to be further linked to biochemical processes and physiological events. The power of metabonomics relies on its unique ability to assess functional changes in the metabolism of complex organisms stemming from multiple influences such as lifestyle and environmental factors. In particular, metabolic profiles encapsulate information on the metabolic activity of symbiotic partners, i.e. gut microflora, in complex organisms, which represent major determinant in nutrition and health. Therefore, applications of metabonomics to nutrition sciences led to the nutrimetabonomics approach for the classification of dietary responses in populations and the possibility of optimized or personalized nutritional management.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 4","pages":"251-64"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2008_097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27691256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Obesity is associated with a decreased risk of breast cancer in premenopausal women but an increased risk in postmenopausal women, an effect that increases with time since menopause. Analysis of these effects of obesity shows that there is a ceiling to the carcinogenic effect of estrogen on the breast; increases in nonsex hormone-binding globulin-bound estradiol (non-SHBG bound E2) exceeding approximately 10.2 pg/ml have no further effect on breast cancer risk; this ceiling is lower than the lowest level seen during the menstrual cycle. This suggests that the effects of menopausal estrogen therapy (ET) and menopausal estrogen-progestin therapy (EPT) on a woman's breast cancer risk will greatly depend on her body mass index (BMI; weight in kilograms/height in meters squared, kg/m2) with the largest effects being in slender women. Epidemiological studies confirm this prediction. Our best estimates, per 5 years of use, of the effects of ET on breast cancer risk is a 30% increase in a woman with a BMI of 20 kg/m2 decreasing to an 8% increase in a woman with a BMI of 30 kg/m2; the equivalent figures for EPT are 50% and 26%. The analysis of the effects of estrogen also shows that even reducing the dose of estrogen in ET and EPT by as much as a half will have little or no effect on these risks. Reducing the progestin dose is likely to significantly reduce the risk of EPT: this is possible with an endometrial route of administration.
{"title":"Estrogens, progestins, and risk of breast cancer.","authors":"M C Pike, A H Wu, D V Spicer, S Lee, C L Pearce","doi":"10.1007/2789_2007_059","DOIUrl":"https://doi.org/10.1007/2789_2007_059","url":null,"abstract":"<p><p>Obesity is associated with a decreased risk of breast cancer in premenopausal women but an increased risk in postmenopausal women, an effect that increases with time since menopause. Analysis of these effects of obesity shows that there is a ceiling to the carcinogenic effect of estrogen on the breast; increases in nonsex hormone-binding globulin-bound estradiol (non-SHBG bound E2) exceeding approximately 10.2 pg/ml have no further effect on breast cancer risk; this ceiling is lower than the lowest level seen during the menstrual cycle. This suggests that the effects of menopausal estrogen therapy (ET) and menopausal estrogen-progestin therapy (EPT) on a woman's breast cancer risk will greatly depend on her body mass index (BMI; weight in kilograms/height in meters squared, kg/m2) with the largest effects being in slender women. Epidemiological studies confirm this prediction. Our best estimates, per 5 years of use, of the effects of ET on breast cancer risk is a 30% increase in a woman with a BMI of 20 kg/m2 decreasing to an 8% increase in a woman with a BMI of 30 kg/m2; the equivalent figures for EPT are 50% and 26%. The analysis of the effects of estrogen also shows that even reducing the dose of estrogen in ET and EPT by as much as a half will have little or no effect on these risks. Reducing the progestin dose is likely to significantly reduce the risk of EPT: this is possible with an endometrial route of administration.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 1","pages":"127-50"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2007_059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27487550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Molecular imaging of tumor metabolism and apoptosis.","authors":"U. Haberkorn, A. Altmann, W. Mier, M. Eisenhut","doi":"10.1007/2789_2008_092","DOIUrl":"https://doi.org/10.1007/2789_2008_092","url":null,"abstract":"","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":"49 1","pages":"125-52"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77559091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Otto, B. Rohde-Schulz, G. Schwarz, I. Fuchs, M. Klewer, H. Altmann, K. Fritzemeier
{"title":"In vivo characterization of progestins with reduced non-genomic activity in vitro.","authors":"C. Otto, B. Rohde-Schulz, G. Schwarz, I. Fuchs, M. Klewer, H. Altmann, K. Fritzemeier","doi":"10.1007/2789_2008_077","DOIUrl":"https://doi.org/10.1007/2789_2008_077","url":null,"abstract":"","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":"19 1","pages":"151-70"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77653428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
c-MYC and the hypoxia-inducible factors (HIFs) are critical factors for tumorigenesis in a large number of human cancers. While the normal function of MYC involves the induction of cell proliferation and enhancement of cellular metabolism, the function of HIF, particularly HIF-1, involves adaptation to the hypoxic microenvironment, including activation of anaerobic glycolysis. When MYC-dependent tumors grow, the hypoxic tumor microenvironment elevates the levels of HIF, such that oncogenic MYC and HIF collaborate to enhance the cancer cell's metabolic needs through increased uptake of glucose and its conversion to lactate. HIF is also able to attenuate mitochondrial respiration through the induction of pyruvate dehydrogenase kinase 1 (PDK1), which in part accounts for the Warburg effect that describes the propensity for cancers to avidly take up glucose and convert it to lactate with the concurrent decrease in mitochondrial respiration. Target genes that are common to both HIF and MYC, such as PDK1, LDHA, HK2, and TFRC, are therefore attractive therapeutic targets, because their coordinate induction by HIF and MYC widens the therapeutic window between cancer and normal tissues.
{"title":"The interplay between MYC and HIF in the Warburg effect.","authors":"C V Dang","doi":"10.1007/2789_2008_088","DOIUrl":"https://doi.org/10.1007/2789_2008_088","url":null,"abstract":"<p><p>c-MYC and the hypoxia-inducible factors (HIFs) are critical factors for tumorigenesis in a large number of human cancers. While the normal function of MYC involves the induction of cell proliferation and enhancement of cellular metabolism, the function of HIF, particularly HIF-1, involves adaptation to the hypoxic microenvironment, including activation of anaerobic glycolysis. When MYC-dependent tumors grow, the hypoxic tumor microenvironment elevates the levels of HIF, such that oncogenic MYC and HIF collaborate to enhance the cancer cell's metabolic needs through increased uptake of glucose and its conversion to lactate. HIF is also able to attenuate mitochondrial respiration through the induction of pyruvate dehydrogenase kinase 1 (PDK1), which in part accounts for the Warburg effect that describes the propensity for cancers to avidly take up glucose and convert it to lactate with the concurrent decrease in mitochondrial respiration. Target genes that are common to both HIF and MYC, such as PDK1, LDHA, HK2, and TFRC, are therefore attractive therapeutic targets, because their coordinate induction by HIF and MYC widens the therapeutic window between cancer and normal tissues.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 4","pages":"35-53"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2008_088","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27690207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mitochondria contained in cancer cells exhibit two major alterations. First, they are often relatively resistant to the induction of mitochondrial membrane permeabilization (MMP), which is the rate-limiting step of the intrinsic pathway of apoptosis. The mechanisms of MMP resistance have come under close scrutiny because apoptosis resistance constitutes one of the essential hallmarks of cancer. Second, cancer cell mitochondria often exhibit a reduced oxidative phosphorylation, meaning that ATP is generated through the conversion of glucose to pyruvate and excess pyruvate is then eliminated as the waste product lactate. This glycolytic mode of energy production is even observed in conditions of high oxygen tension and is hence called anaerobic glycolysis. Here, we discuss the molecular mechanisms accounting for inhibition of the mitochondrial apoptosis pathway in neoplasia and discuss possible mechanistic links between MMP resistance and anaerobic glycolysis.
{"title":"Mitochondria and cancer.","authors":"P Rustin, G Kroemer","doi":"10.1007/2789_2008_086","DOIUrl":"https://doi.org/10.1007/2789_2008_086","url":null,"abstract":"<p><p>Mitochondria contained in cancer cells exhibit two major alterations. First, they are often relatively resistant to the induction of mitochondrial membrane permeabilization (MMP), which is the rate-limiting step of the intrinsic pathway of apoptosis. The mechanisms of MMP resistance have come under close scrutiny because apoptosis resistance constitutes one of the essential hallmarks of cancer. Second, cancer cell mitochondria often exhibit a reduced oxidative phosphorylation, meaning that ATP is generated through the conversion of glucose to pyruvate and excess pyruvate is then eliminated as the waste product lactate. This glycolytic mode of energy production is even observed in conditions of high oxygen tension and is hence called anaerobic glycolysis. Here, we discuss the molecular mechanisms accounting for inhibition of the mitochondrial apoptosis pathway in neoplasia and discuss possible mechanistic links between MMP resistance and anaerobic glycolysis.</p>","PeriodicalId":87471,"journal":{"name":"Ernst Schering Foundation symposium proceedings","volume":" 4","pages":"1-21"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/2789_2008_086","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27694502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}