Hermann Druckrey

Bio: Hermann Druckrey is an academic researcher from Max Planck Society. The author has contributed to research in topics: Carcinoma & Azoxy. The author has an hindex of 32, co-authored 88 publications receiving 4765 citations. Previous affiliations of Hermann Druckrey include University of Bonn.

[Transplacental induction of malignant tumors of the nervous system. I. Ethyl-nitroso-urea (ENU) in BD IX rats].

Abstract: Eine einmalige Gabe von ANH an trachtige BD IX-Ratten am 15. Tage der Schwangerschaft injiziert, fuhrte bei praktisch allen Nachkommen zu malignent Tumoren im Gehirn, an Gehirnnerven, im Ruckenmark und peripheren Nervensystem. Selbst nach 5 mg/kg (2% der LD 50) wurde noch eine Tumor-Ausbeute von 63 Prozent beobachtet. Bei erwachsenen Ratten waren dagegen 200 mg/kg fur die gleiche Wirkung erforderlich. Die Empfindlichkeit des Nervensystems wahrend der pranatalen Entwicklung ist daher etwa 50 fach groser.

Pathology of experimental neurogenic tumors chemically induced during prenatal and postnatal life

Abstract: Among the neoplasms of the human body, those of the nervous system belong in a special category, not in regard to the general characteristics of neoplastic growth but rather to the peculiarities dictated by the functional and morphological specificity and heterogeneity of the organ from which these tumors are derived. The complicated structural organization of the nervous system, compared with other organs, and its cellular and regional diversity explain the following characteristics of neurogenic tumors: wide range of morphological variability, inherent tendency toward infiltrative and destructive growth, variable growth rate without extraneural metastasis, close relationship between type of neoplasm and the site at which it generally occurs, and ageand sex-dependent incidence. One can safely state that the classical, morphology-oriented research in human neurooncology, with the attempt to describe and classify brain tumors in detail, has come to an end, although there are still some unresolved differences of opinions regarding tumor classification (Ziilch, 1948, 1956, 1965; Kernohan & Sayre, 1952; Henschen, 1955; Russell & Rubinstein, 1963; Polak, 1966; Zulch & Wechsler, 1968). Experimental neurooncology is essential, since fundamental questions regarding etiology and pathogenesis of human neurogenic tumors are still unanswered. A thorough knowledge of the characteristics of human neurogenic tumors is, however, a necessary prerequisite for the direction of experimental research and for the proper comparative evaluation of the results obtained by experimental means. This monograph is entitled “Research in the Experimental and Clinical Aspects of Brain Tumors.” Therefore, we decided to give preference in this paper to results obtained from experimental neurooncology. Special emphasis is placed on a new model dealing with resorptive carcinogens, developed in Professor Druckrey’s department,

[selective induction of bladder cancer in rats by dibutyl- and n-butyl-n-butanol(4)-nitrosamine].

Abstract: 1. Dibutylnitrosamin, das nach oraler Gabe an Ratten mit etwa gleicher Haufigkeit Carcinome der Leber, Speiserohre und Blase erzeugt, fuhrte bei subcutaner Injektion (wochentlich einmal 200 bzw. 400 mg/kg) nach 208 bzw. 334 Tagen bei allen Tieren zu Blasenkrebs. Die Ursache der organotropen Wirkung wird in einer endstandigen Hydroxylierung eines Butyl-Restes vermutet. 2. Nach Injektion von 1000 mg Dibutylnitrosamin pro kg wurde im Urin mit der Dunnschichtchromatographie keine unveranderte Substanz gefunden. Wohl aber waren mehrere wasserlosliche Metaboliten mit eindeutiger Nitrosamin-Struktur nachweisbar. Ihre Konzentration war im Urin 10 bis 100fach hoher als im Blut oder Serum. 3. Die Synthese von Butyl-butanol(4)-nitrosamin wird beschrieben die Substanz durch Elementaranalyse und physikalische Daten charakterisiert. 4. Butyl-butanol(4)-nitrosamin erzeugte bei taglicher Gabe von 20 bzw. 40 mg/kg Korpergewicht im Trinkwasser nach einer mittleren Induktionszeit von 280 Tagen bei allen uberlebenden Ratten ausschlieslich Carcinome der Harnblase. 5. Die biochemischen Grundlagen und die Bedeutung der endstandigen Hydroxylierung fur die organotrope Wirkung des Nitrosamins werden diskutiert.

Tobacco Smoke Carcinogens and Lung Cancer

Abstract: The complexity of tobacco smoke leads to some confusion about the mechanisms by which it causes lung cancer. Among the multiple components of tobacco smoke, 20 carcinogens convincingly cause lung tumors in laboratory animals or humans and are, therefore, likely to be involved in lung cancer induction. Of these, polycyclic aromatic hydrocarbons and the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone are likely to play major roles. This review focuses on carcinogens in tobacco smoke as a means of simplifying and clarifying the relevant information that provides a mechanistic framework linking nicotine addiction with lung cancer through exposure to such compounds. Included is a discussion of the mechanisms by which tobacco smoke carcinogens interact with DNA and cause genetic changes--mechanisms that are reasonably well understood--and the less well defined relationship between exposure to specific tobacco smoke carcinogens and mutations in oncogenes and tumor suppressor genes. Molecular epidemiologic studies of gene-carcinogen interactions and lung cancer--an approach that has not yet reached its full potential--are also discussed, as are inhalation studies of tobacco smoke in laboratory animals and the potential role of free radicals and oxidative damage in tobacco-associated carcinogenesis. By focusing in this review on several important carcinogens in tobacco smoke, the complexities in understanding tobacco-induced cancer can be reduced, and new approaches for lung cancer prevention can be envisioned.

Differentiated Rat Glial Cell Strain in Tissue Culture

Abstract: Rat glial tumors, induced by injections of N-nitrosomethylurea, were plated and propagated in culture. Among a few cell strains obtained, one clone contains S-100 protein, which is unique to brain in vertebrates. Stationary-phase cultures contain approximately ten times more S-100 protein per cell than exponentially growing cells. When injected into newborn rats, cells producing S-100 grew as a glial tumor, which contained S-100 protein.

The role of glutathione and glutathione S-transferases in the metabolism of chemical carcinogens and other electrophilic agents.

Abstract: Publisher Summary This chapter discusses the role of glutathione (GSH) and glutathione s-transferases in metabolism of chemical carcinogens and other electrophilic agents. GSH is a tripeptide (I) that is present in nearly all living cells and is the most abundant sulfhydryl compound present in animal tissues, mainly in the cytosol. The chapter illustrates the wide range of electrophilic agents, including several known mutagens and carcinogens, which conjugate with GSH, a process usually catalyzed by the GSH S-transferases. This conjugation is probably a protective mechanism and is the initial stage in mercapturic acid biosynthesis for the elimination of foreign compounds from the body. GSH S-transferases provide protection not only by catalyzing the conjugation of a potential toxicant with GSH, but also by preferentially binding, even covalently, that toxicant. The reactive electrophiles that conjugate with GSH also bind to DNA, RNA, and protein and identification of GSH conjugates provide information on the nature of these biologically active intermediates or even their immediate precursors. Thus, the knowledge of the way in which mutagens and carcinogens are metabolized is essential to a better understanding of their mode of action and of the processes for their detoxication.