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S Tanneberger

Publications and source records attributed to S Tanneberger.

At least 55 records · Page 3Linked to original sources
PubMed1987

[Adjuvant chemotherapy in cancer surgery].

Isolated surgical approaches to tumor treatment have largely reached a point beyond which prospects appear to be unpromising. The search for more promising therapeutic approaches, therefore, has become a compelling challenge. Surgico-adjuvant tumour chemotherapy has been more thoroughly studied than anything else in that direction. The underlying theoretical concept seems to be persuasive, though clinical results have so far stayed below expectations. Secured prolongation of life, following this therapy, has so far proved to be probable only for cases of osteosarcoma, mammary carcinoma with high risk of recurrence, testicular tumours, and neurogenic tumours. Neo-adjuvant chemotherapy seems to work well in cases of ENT tumours. Model studies into Lewis-Lung carcinoma have shown that therapeutic effects cannot be guaranteed unless a sensitised tumour is treated with an effective preparation. This is likely to add to the long-range importance of the individual aspects relating to surgico-adjuvant tumour chemotherapy. Methods have been and continue to be developed for that purpose. Yet, all of them need to be methodologically improved. At present, waiting for such improvement, surgico-adjuvant tumour chemotherapy should be used only within the framework of controlled clinical studies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Establishment of a tumor cell line and its use for an agar-free colony-forming assay.

The establishment of a spontaneously transformed tumorigenic human fibrosarcoma line derived from the ovary of a breast cancer patient (NO-15) is described. This tumor cell line has been characterized by tumor growth in nude mice. The cells form colonies without the usually recommended agar technique and are sensitive to cis-dichlorodiammineplatinum(II) (cis-DDP), daunorubicin (DR) and bleomycin (BLM), three well-known chemotherapeutic agents. The cells were incubated in the presence of drugs using three different methods. These agents proved to be noncytotoxic to monolayers treated for three hours. Conversely dose-dependent cytotoxicity was seen in suspension cultures treated for three hours. Optimal correlation between the three methods for the evaluation of cytotoxicity was seen in monolayers exposed to these agents for 24 hours. The results of three different methods to evaluate drug efficacy (number of colonies, growth rate and 3H-thymidine incorporation) were in good correlation. The incorporation of the radiolabeled tracer into cellular DNA is advantageous for its rapidity and quantitative reproducibility.

Adult↗
PubMed1986

[Chemotherapy alternatives, problems and outlook in testicular tumors].

The treatment of testicular tumors is among the most impressive examples of progress in tumor chemotherapy. At present, a complete remission can be achieved with the world-wide adopted standard therapy Cisplatinum/Vinblastine/Bleomycin in 50-80% of the cases. Whether these remissions are equivalent to healing remains to be established in long-term studies; at any rate, they are long-term palliations. Main problems of further research are the high-risk patients. Approaches to reach complete remissions and thus long-term palliations or healing, consist in increase of combination, dose escalation with Cisplatinum, introduction of novel substances (Etoposide, Ifosfamide etc.). The latter field is scientifically underdeveloped, as is the field of second- and third-order therapy. After all, chemotherapy of testicular tumors--similarly as treatment of leukemia--is an oncological intensive therapy that should be restricted to specialized centers.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1986

Effects of nifedipine on cell resistance and cardiac toxicity--in vitro and in vivo experiments.

Nifedipine can enhance the cytotoxicity of antineoplastic drugs. The present paper describes characteristics of sensitive and acquired resistant cells prior to and after transplantation into nude mice and experiments to reverse the acquired resistance to Daunorubicin (DR) by Nifedipine. Resistant cells (HT/DR+) are characterized by prolonged doubling time and diminished drug sensitivity and drug uptake. HT/DR+ cells show a slightly increased number of polyploid cells. These characteristics are not changed after nude mouse transplantation. Nifedipine enhances the intracellular level of Daunorubicin and cytotoxicity in vitro and in vivo in case of HT/DR+ cells. But Nifedipine acts both in vitro and in vivo also on sensitive cells (HT). This could support the hypothesis that Nifedipine increases the toxicity, which could be confirmed by experiments on mice (B6D2F1 strain). But probably the increased incidence of toxic deaths is not due to increased cardiac toxicity. This increase of toxicity could limit the clinical usefulness of the combination of antineoplastic drugs with calcium channel blockers.

Animals↗
PubMed1985

[Antineoplastic chemotherapy for bronchial carcinoma].

With the non small-cell bronchial carcinoma, the results of tumor chemotherapy are, on the whole, still unsatisfactory. It remains to be seen whether the more recent preparations, such as Cisplatin, VP16, Vindesine or combinations there of which are at present extensively investigated, will change this situation. The combinations: Cyclophosphamide/Doxorubicin/Methotrexate/Procarbazine, Cyclophosphamide/Doxorubicin/Cisplatin or Vindesine/Cisplatin are considered most prospective, were remission rates are reported to range from 30-40% with a mean period of remission from 5-7 months. Such values are approximatively reached also by monochemotherapy, e.g. Cyclophosphamide, Adriamycin or Vinblastine. Thus, radiotherapy combined, if necessary, with tumor chemotherapy continues to be the therapy of choice for the non small-cell bronchial carcinoma. Entirely different is the situation with the small-cell bronchial carcinoma. Here, with polychemotherapy being clearly superior to monochemotherapy, 80% of objective remissions are achieved with limited extension of the tumor, and 65%, with advanced tumor progression. The remissions may last here up to 18 months. Combinations of proven value are: Doxorubicin/Cyclophosphamide/Vincristine and VP16/Doxorubicin/Cyclophosphamide, with Cyclophosphamide being contained virtually in all proposed combinations as an essential component. Repeatedly proposed has also been the alternating application of non cross-resistant therapeutic schedules, e.g. VP16/Procarbazine and Cyclophosphamide/Lomustine/Vincristine/Procarbazine. For the inoperable small-cell bronchial carcinoma, chemotherapy is the therapy of choice. In how far additional radiotherapy will further improve the therapeutic results is now being intensively investigated. A high likelihood in this regard exists for a "prophylactic" irradiation of the CNS.

Antineoplastic Agents↗
PubMed1984

[10 years' use of ftorafur in tumor chemotherapy at the Robert Rössle Institute. A retrospective analysis from the clinical-toxologic point of view].

A retrospective analysis from the clinical-toxicological point of view Within a ten-year period a group of 130 patients treated with Ftorafur (FT) was selected randomly and 124 of these patients were evaluated with regard to therapeutic side effects using objective criterions. FT founded to be a therapeutic effective cytostatic drug with only a low level of therapeutic side effects. So FT seems to be combinable with more toxic cytostatics without additional serious toxicity for non-tumor tissues. The peroral FT-application was followed only by low graded side effects in comparison with a higher incidence after intravenous injection or infusion. Most observed FT side effects were: nausea and vomiting, toxic effects on the hematopoetic system and alopecia. No serious neurotoxic effects were observed.

Adult↗
PubMed1984

Investigations on the instability of drug sensitivity in dependence on culture and transplantation conditions in case of a human lung carcinoma.

Changes of biological properties, DNA-distribution patterns and drug sensitivity testing in vivo and in vitro after different culture and transplantation conditions in case of a human lung carcinoma are described. While DNA-distribution patterns of cells before any culture (OSC, TC 0) showing two clearly different aneuploid cell populations (DNA-index DI: 3.9 and 4.9), cells after 8 passages (TC 8) in vitro demonstrate only one cell population. These cells do not differ from double value (4C) of diploid cells (2C). DNA-distribution patterns of cells of solid tumors grown in nude mice (nu/nu 2089-1) show a cell population with DI 6.3. In line with these results, cells and tissues after different culture and transplantation conditions exhibit variable drug sensitivities. The lung carcinoma (OSC) shows clear reactions measured either by 3H-thymidine or 3H-deoxyuridine in the presence of Cyclophosphamide and Methotrexate. Adriblastin and 5-Fluorouracil did not show any effects after 48 hours treatment. Cultivated cells (TC 8) were sensitive against all antineoplastic drugs tested. Tumor tissue grown in nude mice (nu/nu 2089-1) shows the strongest effect after 5-Fluorouracil treatment both in vitro and in vivo. Selection of different cell population were discussed with regard to these findings.

Adenocarcinoma↗
PubMed1984

[In vitro cell and tissue cultures as a model for studying human tumors].

An experimental in vitro or in vivo tumour model should be unchanged represent the biological properties (e.g. histology, proliferation). Changes of tumour cell populations were determined by means of DNA-distribution and multinucleation after cytochalasin B treatment. Flow cytometry measurements on cell cultures in 50 ml glass culture flasks reveal reduction of polyploid cells after collagenase treatment of human mammary carcinomas. Selection of cell populations are responsible for the failed induction of multinucleation by cytochalasin B. In organ cultures the composition of cell population prior to and after 48 hours could maintained. The improved penetration could be demonstrated by autoradiographic measurements of 3H-thymidine incorporation. Thickness, surface and improved penetration of metabolites of vital tissue slices seem to be also important for cell movement and cell division. In 10 out of 12 experiments an earlier cell migration and proliferation could be observed from vital slices than from tissue pieces. Organ cultures represent sufficiently carcinoma in vivo and are more suitable than other mentioned in vitro cell culture methods.

Autoradiography↗
PubMed1983

[In vitro cultivation of vital tissue slices: a new variation of organ culture technics].

A new modification of the organ culture technique is described. In contrast to the conventional technique in which organ pieces (1 mm3) are cultivated, uniform, viable, microscopically controlled tissue slices are used in a modified organ culture technique. The new method is suitable for in vitro culture of human mammary carcinoma. Flow cytometry measurements reveal changes prior to and after collagenase treatment of human mammary carcinomas. In organ culture the composition of cell population prior to and after 48 h could be maintained. Examination under the microscope confirmed these results. The uptake of [3H]-thymidine was greater in tumor slices than in tumor pieces. Organ cultures sufficiently represent carcinoma in vivo in comparison to the other mentioned in vitro techniques.

Breast Neoplasms↗
PubMed1983

[Animal experimental examination of a phase III study on the effect of the combination therapy of bruneomycin, cytostasan and prednisone].

The effectivity of a combined application of Bruneomycin, Cytostasane and Prednisone has been tested in five qualitatively different experimental animal test models. The selected dose levels and the treatment schedule were based on an instruction given in a phase III-study. No effectivity was demonstrable in any of the tumor systems selected neither with the single components, nor with their combination, though the toxicity clearly revealed a dose dependence.

Animals↗
PubMed1983

In vitro characteristics of a human mammary carcinoma prior to and after transplantation into nude mice.

Single cells from a patient (B.E., 65 years) have been isolated by collagenase treatment and cultivated in vitro. The human tumour showed predominantly simple undifferentiated and also tubular structures. The 5th in vitro passage of these cells were characterized by growth curves, DNA-distribution patterns and chromosome numbers. Cells of the 5th in vitro passage were i.p. transplanted in nude mice. The characteristics of the 21st passage of ascitic cells and solid tumour material grown in nude mice were compared with cell characteristics of the 5th in vitro passage. Our results demonstrate that malignant cells (ascitic) are best able to proliferate in vitro after transplantation into nude mice. The number of polyploid cells are increased in this cell population. DNA-distribution patterns and chromosome numbers show a good correlation. Biological properties of human neoplastic cells are dependent on environmental factors.

Aged↗
PubMed1983

[Measurements of ion concentrations with microelectrodes on vital tissue sections of human breast cancer].

The transmembrane potential (TMP) was described as a rapidly reacting and sensitive indicator for a great number of cell functions. The present paper reports on the measurement of ion concentration (IC) on vital microscopically controlled human mammary tissue slices. Satisfactory results have been achieved with changed on-light observation in comparison to other customary methods. Whereas a cytoxic effect has been observed with all treatments by means of 3H-thymidine uptake, IC-measurements showed only effects with Daunoblastin or distilled water in 4 out of 16 experiments. The effect of Daunoblastin measured by ion concentrations seems to be better visible if the tissue culture medium is exchanged by physiological NaCl-solution (0.9%). Nevertheless the described method cannot be recommended for drug sensitivity testing of human mammary carcinomas in organ culture.

Breast Neoplasms↗