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K Goerttler

Publications and source records attributed to K Goerttler.

At least 55 records · Page 3Linked to original sources
PubMed1982

Effect of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate and its nonpromoting analogue 4-O-methyl-TPA on dorsal dermal melanocytes of the Syrian golden hamster (Mesocricetus auratus).

The effect of the tumor promoter TPA and its inactive structural analogue 4-O-methyl-TPA on the induction of dorsal skin melanosis in the normal Syrian golden hamster and on the promotion of melanomas in DMBA-initiated animals was investigated. Both phenomena were observed in TPA-treated hamsters but could not be detected after exposure of animals to 4-O-methyl-TPA. In contrast to results obtained with a variety of other laboratory animals, neither TPA nor 4-O-methyl-TPA were able to induce epidermal hyperplasia of hamster dorsal skin.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

A reliable preparation of mon-dispersed chromosome suspensions for flow cytometry.

A reproducible, simple and rapid protocol was developed to prepare mono-dispersed chromosome suspensions for flow cytometric analysis. The procedure basically employes: 1. twice rinsing of monolayer cultures to eliminate dead cells and cellular debris, 2. mild fixation of mitotic cells with 1% acetic acid, and 3. ultra sonic treatment to release single metaphase chromosomes. The procedure takes less than 30 min. Isolated chromosomes are storable over months at 4 degrees C. Despite mild fixation many biochemical studies and experiments applied on such fixed chromosomes purified and enriched using electronic sorting are feasible: 1. gene and restriction mapping, 2. cloning of specific gene sequences, and 3. gene frequency analysis.

Animals↗
PubMed1982

DNA-flow-cytometric measurements on the normal, atrophic, hyperplastic and neoplastic human endometrium.

DNA distribution patterns and the fractions of the cell cycle phases were determined by means of flow-through cytometry in 87 samples of normal, atrophic, hyperplastic and carcinomatous human endometrium. The S-phase fractions vary during the normal menstrual cycle between 1 and 3% and reach a periovulatory maximum between 4.4 and 4.7%. Atrophic endometrium and regressive glandular cystic hyperplasia have little DNA synthesis (1.01% and 1.68% S-phase fractions respectively). Proliferating glandular cystic hyperplasia reveals 3.38% S-phase fraction, whereas adenomatous hyperplasia has an increased number of DNA-synthesizing cells (4.81%). The well-differentiated endometrial carcinoma shows no cytophotometrically detectable differences in comparison to adenomatous hyperplasia. All endometrial samples except for poorly differentiated endometrial carcinoma showed a diploid to tetraploid DNA distribution pattern. The poorly differentiated endometrial carcinoma displays two different types: one rapidly growing diploid-tetraploid tumor with 8.0 to 9.6% S-phase fractions, and another type with stemline deviations, polyploid nuclei and less pronounced synthetic activity.

Adenoma↗
PubMed1982

7,12-Dimethylbenz[a]anthracene/12-O-tetradecanoyl-phorbol-13-acetate-mediated skin tumor initiation and promotion in male Sprague-Dawley rats.

In contrast to a previous report by Shubik and in accordance with a pilot study from our laboratory with female rats, the 2-stage skin carcinogenesis experiment could be successfully accomplished in male Sprague-Dawley rats. Male animals of this species are better suited for this long-term experiment since, under the conditions used, females are very sensitive to mammary gland tumor formation and show a drastically reduced survival time. A broad spectrum of tumors of epidermal origin could be induced by topical initiation with 7,12-dimethylbenz[a]anthracene (DMBA) and 12-O-tetra-decanoyl-phorbol-13-acetate (TPA) as promoter. The tumors were not only localized in the interfollicular epidermis but to a large extent also in the epidermal appendages. More importantly, the DMBA - TPA treatment led to the development of a variety of tumors of the connective tissue and the angiofibrous matrix. The incidence of these tumors was almost comparable to that found for epidermal tumors. In some animals we observed up to 12 histologically different tumors. Compared to the mouse, the tumor incidence in organs other than the skin was definitely lower. Ethyldiazoacetate (EDA), a substance which has been shown to induce skin tumors when administered i.v. to rats, was tested with regard to its initiating capacity. The combination EDA-TPA led to a skin tumor spectrum comparable to that produced by DMBA-TPA. However, the survival time of the EDA-TPA treated animals was significantly higher than those exposed to DMBA-TPA. EDA, therefore, seems to be a suitable alternative to DMBA for systemic initiation of skin tumors.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Tumor initiation by 7,12-dimethylbenz[a]anthracene in dermal melanocytes of hamster: inhibition through 7,8-benzoflavone.

Initiation of dermal melanocytes by 7,12-dimethylbenz[a]-anthracene (DMBA) in the dorsal skin of Syrian golden hamsters was investigated for its sensitivity to inhibition by 7,8-benzoflavone (BF). Initiation was carried out by a single intragastric application of DMBA (50 mg/kg body weight) and melanoma development pursued with or without subsequent promotion through repeated topical administration of 12-O-tetradecanoylphorbol-13-acetate (40 nmol/animal, 3 X weekly). A single intragastric application of BF (200 mg/kg body weight) 2 h prior to DMBA resulted in a suppression of melanoma yields by approximately 70%. Further, there were indications that BF generally causes a decrease of melanoma rates and an increase of survival rates. The study provides a first mechanistic concept for melanoma initiation by DMBA. It shows that metabolic activation of DMBA (i) is prerequisite to initiation and (ii) has a similar molecular basis as in other target cells of DMBA, the essential pathway including the cytochrome P-448-dependent monooxygenase system.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Automated cytology. The state of the art.

Analytical cytology is the science of automatically analyzing morphologic, biochemical, biophysical, and functional aspects of cells by machine. Two basic techniques are used: image cytometry, in which microscopic objects on a slide or in a photograph are analyzed; and flow cytometry, in which biologic particles in aqueous suspensions are forced to pass through a measuring device. The latter technique has the added power of sorting particles according to type for further study. Currently, analytic cytology is being studied for use in the following areas: WBC differentiation, cell-cycle kinetics, prescreening for uterine cancer, screening of high-risk groups, monitoring of tumor therapy, and microbial and chromosome analysis. In all these areas, analytic cytology has the potential to improve existing techniques and to make results more uniform; likewise, its sensitivity, accuracy, and speed may well allow a breadth and depth of analysis not presently allowed by human study.

Automation↗
PubMed1981

Diaplacental initiation of NMRI mice with 7,12-dimethylbenz[a]anthracene during gestation days 6--20 and postnatal treatment of the F1-generation with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate: tumor incidence in organs other than the skin.

The tumor spectrum and tumor incidence in organs other than the skin were investigated in the 12-O-tetradecanoylphorbol-13-acetate (TPA) treated F 1-generation of 13 groups of NMRI mice which had been initiated by a single intragastric dose of 7,12-dimethylbenz[a]anthracene during days 6, 8, and 10--20 of pregnancy. Promotion by topical application of TPA to the back skin was carried out twice per week 12 weeks after birth over a period of 26 weeks. The forestomach epithelium represented the only organ in which statistically significant 2-stage carcinogenesis could be demonstrated. A promotion effect could be seen in tumors of the Harderian gland, of the liver of male animals and on the development of both benign and malignant tumors of the lung in both sexes. Promotion treatment therefore led to an activation of initiated tumor cells in those organs in which a very sensitive, more or less narrowly spaced oncogenic determination period exists.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1980

Two-stage skin carcinogenesis by systemic initiation of pregnant mice with 7,12-dimethylbenz(a)anthracene during gestation days 6-20 and postnatal promotion of the F 1-generation with the phorbol ester 12-tetradecanoylphorbol-13-acetate.

The DMBA-TPA-mediated two-stage skin carcinogenesis experiment was modified in that pregnant mice were systemically treated once during pregnancy with the carcinogen. Intragastric application times were fetal days 6, 8, and 10-20. A control group of pregnant mice received repeated doses (from days 8-20) of sesame oil, which was used as a solvent for DMBA. At the age of 12 weeks, the offspring of the control group were divided into two groups, one of which was left completely untreated, the other received TPA applications over 26 weeks. The 12-week old F 1-progeny of each transplacentally initiated group was also divided into subgroups, which either received no further treatment (subgroups A) or were promoted with TPA (subgroups B). Neither the F 1-animals of the two control groups nor that of the transplacentally initiated but postnatally not promoted subgroups 6 A-20 A developed skin tumors. The same holds true for the TPA-promoted offsprings of mother animals which had received DMBA at days 6 and 8 of gestation. Skin tumor development after TPA promotion was first observed in animals of subgroup 10 B. Thereafter, tumor rates and tumor yields increased and latency periods decreased progressively in the B-subgroups with the postponement of initiation to later fetal periods. Day 19 of prenatal development proved to be the most sensitive period to transplacental initiation, whereas initiation at day 20 led to a significant decrease in tumor rate and yield. The capability to initiate skin tumors and the extent of initiation can be correlated to both the organogenesis of the epidermis and its proliferative rate in utero.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1980

A flow cytometric study of chromosomes from rat kangaroo and Chinese hamster cells.

Chromosomes from rat kangaroo (PTK) and chinese hamster (CHV 79) cells have been prepared for quantitative flow-cytometric analysis. The preparation time was otimized down to 30 (PTK) and 40 min (CHV 79). DAPI was used as a AT-sensitive fluorescent dye to stain for monoparameter DNA measurements. Simultaneous two-parameter DNA-protein analysis was carried out with DAPI and SR 101 (as a general protein fluorochrome) in combination. The karyotype of the PTK cells with 13 (14) chromosomes was separated into 10DNA peaks. The X-chromosome bearing the nucleolus organizer region generates a distinct peak. The karyotype of the CHV 79 cells with 22 chromosomes was separated inot 15 peaks. The DNA profile obtained indicates a geometric grading of the chromosomal amount of AT components in teh karyotype of this particular cell line. The simultaneous DNA-protein analysis performed show enough sensitivity of the instrument utilizing hihg power UV excitation illumination to discriminate the two color emission consisting of blue (DAPI) and red (SR 101) fluorescence. Color overlapping could be completely avoided. Additionally, the quality (number, location, and resolution of peaks) of the DNA distribution was not influences by the simultaneous application of a second fluorescent stain. Fluorescence activated electronic sorting applied on chromosomal fluorescence distributions providing purified fractions of chromosomes for subsequent biochemical and biological determinations is discussed.

Animals↗
PubMed1980

Keratins as markers of malignancy in mouse epidermal tumors.

A comparative study of the keratin composition of adult and neonatal mouse epidermis, benign and malignant tumors of mouse skin and murine epidermal cells grown in culture revealed striking differences in the keratin polypeptide patterns when analyzed by one-dimensional gel electrophoresis. Not only did the study confirm body-site specific alterations in the keratin patterns within one species, but it also demonstrated that similar to cultured epidermal cells, three malignant skin tumors investigated specifically lacked a group of keratin components with molecular weights larger than 61,000 daltons, which were invariably present in all normal and also in benign tissues. These findings offer the possibility of using keratins as molecular markers of the malignant state of epidermal cells. Two-dimensional gels of the keratin polypeptides of normal epidermis and of benign tumors exhibited spot patterns which could be divided at the 61,000 dalton level into an essentially basic subgroup, comprising the high molecular weight keratins, and an acidic subgroup including the low molecular weight components. The two uppermost proteins of cultured epidermal cells and carcinomas (molecular weights 61,000 and 58,000 daltons) belong to the acidic subgroup in normal tissues as well as in papillomas. However, in the case of malignant tumors and in vitro transformed epidermal cells they showed distinct alterations in charge in that they migrated into the more alkaline part of the gel. The number of spots appearing in the more basic region of the gel could be inversely related to the degree of differentiation exhibited by tumors or in vitro cells.

Animals↗
PubMed1980

Two-stage carcinogenesis in NMRI mice: intravaginal application of 7,12-dimethylbenz[a]anthracene as initiator followed by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate as promoter.

In this study a new modification of the systemic 2-stage carcinogenesis experiment is described. Tumors were induced in NMRI-mice using a single intravaginal application of the carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) (initiator) followed by intravaginal treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) (promotor) as a cocarcinogen over a period of 52 weeks. The substances were applied using small tampons. Development of preneoplastic lesions or neoplasias was not found in the group of untreated control animals (n = 50) and in TPA treated animals (n = 50). However, mice which had been treated with TPA alone showed pronounced hyperplasia. When DMBA was applied without subsequent treatment with TPA (n = 100), formation of preneoplastic lesions was frequently observed. Fibroepitheliomas (papillomas), carcinomas and sarcomas, typically located intravaginally and at the external region of the vagina, were observed after the combined treatment with DMBA and TPA (n = 100). In addition, benign as well as malignant tumors were found, mainly in the forestomach, in DMBA treated animals and more frequently after application of DMBA and TPA. Tumors of the lung and leukemias were identified more frequently in comparison to the normal spontaneous tumor rate in NMRI mice, and were probably in part caused by the promoting substance TPA. On the other hand, no significant tumor formation in the mammary gland and in the ovaries was observed after DMBA/TPA application. The tumors observed in these organs were, however, caused by treatment with the carcinogen DMBA only. This new modification of the 2-stage experiment, i.e. the direct intravaginal application of initiating and promoting substances, has special relevance for the elucidation of the mechanisms involved in the development of carcinomas located at the portio vaginalis uteri in humans.

9,10-Dimethyl-1,2-benzanthracene↗