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M Hänsel

Publications and source records attributed to M Hänsel.

11 recordsLinked to original sources
PubMed2001

A 23-year experience with malignant renal tumors in infancy and childhood.

A retrospective analysis of 77 children treated between 1974 and 1996 was undertaken to evaluate morbidity and the evolution of therapy. A Wilms' tumor (WT) was present in 73 children. 74% of patients (pats.) with WT survived (54 of 73 pats.). Histological specimens of 67 patients were re-evaluated, including 4 children with non-WT histology. Among patients with Wilms' tumors (WT), nephroblastoma (NB) of intermediate risk predominated (73%; 46 of 63 pats.). Low-risk tumors occurred in 5 of 63 children (8%; mesoblastic nephroma 3, cystic partially diff. NB 1, completely necrotic NB 1). High-risk WT were diagnosed in 12 of 63 patients (19%) (NB with anaplasia 10, clear cell sarcoma 1, malignant rhabdoid tumor 1). Nephrogenic rests were present in 14 cases. We observed 3 children of school age with renal carcinoma and one patient with an intrarenal neuroblastoma. WT histology was the most important factor determining prognosis (p = 0.018). The risk for relapses was 2.6-fold higher in patients with high-risk WT compared to the standard risk group. Stages were re-evaluated according to SIOP 93-01. Comparing relapse-free survival of stages I, II and III, respectively, there was a reduced survival rate for stage III (p=0.019). According to the SIOP/GPOH protocol in 1989, the regimen was switched from primary surgery to preoperative chemotherapy without biopsy in 1989 (11 pats.). Compared to earlier years, survival improved (n.s.). In 3 patients preoperative diagnosis by means of imaging failed. During preoperative chemotherapy a venous occlusive disease of the liver occurred in 2 patients. Preoperative chemotherapy led to an impressive tumor shrinkage in the majority of patients. 2 patients of the preoperative group died (focal anaplastic NB). Long-term morbidity was analysed in 49 patients and included radiation-induced scoliosis (35), chest-wall deformity (3), congestive cardiomyopathy after relapse (1) and arterial hypertension (2). Over the years there was a trend to reduce frequency and dose of irradiation. Prognosis of WT is excellent but unfavorable histology (high risk) predicts a poor prognosis. In our experience, reduction of tumor volume due to preoperative chemotherapy facilitates tumor removal by surgery and may prevent tumor spillage and the deleterious effects of radiation in young children. Surgery without delay is necessary if the diagnosis is unclear or the tumor fails to respond to preoperative chemotherapy.

Antineoplastic Agents↗
PubMed1994

Karyotype analyses of 20 human glioma cell lines.

Human malignant gliomas are frequently associated with loss of gonosomes and chromosomes 13, 17, and 22. Their progression from anaplastic glioma to glioblastoma is marked by additional loss of chromosome 10. In addition, structural and numerical aberrations of chromosome 7 are frequently found. We report on the karyotypes of a series of 20 human gliomas of which 11 were analysed as established cell lines; 9 cases were investigated in early culture, 5 of which later also became established lines. In addition to the frequently reported overrepresentation of chromosome 7, four cell lines with polysomy for chromosome 22 were seen. A high incidence of structural chromosomal aberrations was present in early cultures as well as in cell lines after various in vitro passages. We found that the general characteristics of karyotypic aberrations found in early cultures or direct preparations of dispersed tumour material were reflected in the pattern of aberrations present in cell lines at much later time points. Thus it appears as if no systematic changes can be attributed to long-term cultures. Suspicious losses of chromosomes 14, 18, and 19 or gain of chromosome 22 indicate that individual cases may have originated due to other mechanisms than the ones already hypothesized, i.e., different suppressor genes or amplification of genes other than the EGF-R-gene. None of the established cell lines had a genomic rearrangement of c-erbB 1, c-erbB 2 or of the p 53 gene.

Adult↗
PubMed1991

Primary spinal malignant schwannoma: clinical, histological and cytogenetic findings.

Of the 19 patients who presented between 1980 and 1990 to the Department of Neurosurgery, University of Hamburg, F. R. G. with malignant schwannoma, 5 patients suffered from primary malignant spinal schwannoma (mean age 44 years, only one patient with von Recklinghausen's disease). Here we report the clinical, histological, and cytogenetic features of the five cases with primary malignant spinal schwannoma and discuss the prognostic aspects of this rare tumor.

Adolescent↗
PubMed1989

Spectrum of karyotypic aberrations in cultured human meningiomas.

Twenty-two unselected cases of meningioma were initiated in tissue culture on an extracellular matrix derived from bovine corneal endothelial cells. The cultures were available for karyotypic analysis at passages 1 to 5, representing cultivation periods of up to two months. Histologically, the meningiomas were meningiotheliomatous (16 cases), fibrous (1 case), angiotheliomatous (1 case), microcystic (2 cases), and parenchymatous (2 cases). Two of the meningotheliomatous cases had histological signs of malignancy, another case showed increased signs of proliferation, and two cases were recurrences, one after a complete course of irradiation. In five cases no structural chromosome aberrations were found. Monosomy of chromosome 22 was found in six cases and was associated with other random aberrations. Clonal or random aberrations without monosomy 22 were present in 11 cases, including one case with trisomy 7 and another case with a stable translocation marker, t(4;7). In these latter two cases, EGF-receptor binding was not elevated, compared to other meningiomas. Our results illustrate that, in addition to the frequent involvement of chromosome 22, numerous other individual clonal karyotype aberrations exist in meningioma cell populations, reflecting the heterogeneity of biological and pathological findings.

Adult↗
PubMed1988

Glioma biology in vitro: goals and concepts.

Gliomas are heterogeneous in their cellular composition, affecting therapeutic efforts such as surgical removal, radiotherapy, chemotherapy and immunotherapy. 106 gliomas were taken into culture in our laboratory and 12 cell lines could be established there from. Experiments were carried out in as many early cultures as possible and with the constant experimental system of the cell lines. To subdivide and possibly classify the heterogeneous group of gliomas the following approaches emerged: Immunostaining of cells for glial markers such as GFAP, A4, A2B5, Leu 7 as well as fibronectin will allow one to distinguish different groups of glial cultures. Performance of growth factor sensitivity tests allows the assessment of major aspects of growth control in cultured gliomas. Cytogenetic evaluation in early cultures and correlation with the expression of oncogenes may yield useful information on mechanisms of escape from normal growth control. One of our cell lines (NCE-G28) in which cells switch from GFAP to fibronectin expression and transiently express the x-hapten may serve as a model to study crucial aspects of cellular differentiation. Using different extracellular matrices for the initiation of cultures even from very benign lesions with low proliferative potential it is possible to include these into comparative studies with glioblastomas.

Animals↗
PubMed1988

Clinical and laboratory findings in patients with multiple meningiomas.

A series of eight patients with multiple meningiomas is presented. Up to 14 meningiomas were diagnosed in one patient. The clinical and laboratory findings suggest that multiple meningiomas do not constitute a disease entity of their own featuring disease-specific clinical or laboratory findings. In our series we find a female predominance with seven female and one male patient. The histological findings were mixed, even within the individual cases. There are no consistent patterns of steroid receptor levels or chromosomal aberrations in the more recent cases in which these parameters could be investigated.

Adult↗
PubMed1987

Initiation of primary cell cultures from human intracranial tumors on extracellular matrix from bovine corneal endothelial cells.

Tissue specimens from 105 human gliomas and 57 human meningiomas were obtained at surgery, dissociated into single cells and small cell aggregates and then plated onto plain plastic tissue culture dishes and dishes which had been precoated with an extracellular matrix (ECM) derived from bovine corneal endothelium. In 80% of the glioma cases we observed a marked improvement in initial plating efficiency, colony formation and speed of attachment when cells were plated on ECM. In 5 cases cells attached only to the ECM-coated dishes but remained afloat in the untreated dishes. In addition it could be noted that over the first 2 days, those cells which had been initiated on ECM showed more signs of morphological differentiation, i.e., extension of cytoplasmic processes or formation of fiber networks between cell groups. If adaptation occurred and proliferation began in vitro, either immediately or after a several days' lag phase, both the ECM-cultured cells as well as those which slowly had adapted to culture on plastic could be passed on to untreated culture ware and perpetuated thereon. In the case of well-differentiated low-grade gliomas where no growth in culture took place, the cultures on ECM could at least be used for initial experiments in the primary cultures (P0). Meningiomas usually attached well to both, plastic or ECM. In 50% of our cases the plating efficiency was higher on ECM but after successful initial culture, the delay until the cells on plastic reached confluence in comparison with those on ECM was 1 or 2 days. Again there were 2 cases in which the cells would not plate on plastic. Here the cells which after 1 day were still afloat plated to more than 80% within the first 2 h after transfer to ECM. In all cases the cells from plastic and ECM cultures were indistinguishable and could be passed onto untreated dishes henceforth. In later culture stages ECM offers several advantages: It is easier to shift cells to serum-free defined culture conditions, the cells will grow at a faster rate on ECM when in higher passages and the maximal number of passages possible is higher on ECM.

Animals↗
PubMed1985

Effectiveness of antineoplastic drugs on the proliferation of human mammary and ovarian carcinoma cells in monolayer culture.

Procedures for the in vitro determination of the drug-induced inhibition of mammary and ovarian carcinoma cell growth were established. In monolayer cultures derived from advanced tumors, separation of epithelial carcinoma cells from concomitant cells of fibroblast-like or mesothelial appearance was achieved by differential trypsinization. The carcinoma cell character of the stock cultures was verified by chromosome analyses showing a high degree of aneuploidy for the epitheloid cell lines and euploidy for cells of apparently mesenchymal origin. When cultured carcinoma cells were injected in nu/nu mice, the tissue and cell cultures obtained from the heterotransplantation tumors closely resembled the original tumors and cell cultures in morphology, karyotype, and expression of tumor markers. The action of carcinostatic drugs in the logarithmic phase of the carcinoma cell proliferation was tested by kinetics experiments in multiple experimental cultures. In cell proliferation assays based on cell counts the 50% inhibition dose (ID50) of the drug effects was determined from the dose-response curves. Comparison of the ID50s revealed highly differential effectiveness of the drugs examined. The inhibitory effects were reproducible, rendering the procedures used suitable for testing the chemosensitivity of newly explanted gynecological carcinoma cells by proliferation assays.

Adenocarcinoma↗
PubMed1984

Alteration of steroid hormone sensitivity during the cultivation of human mammary carcinoma cells.

During early cultivation steps of the newly derived and karyotyped human mammary carcinoma line EFM-19, the cells developed faster growth rates and became increasingly less responsive to the presence of serum in the culture medium. No drastic alterations of the morphology and of the karyotype were observed, and carcinoembryogenic antigen remained expressed during the course of the cultivation. In experimental incubations at various time intervals after the explantation, the cell proliferation was analyzed for dose-dependent effects of estradiol, cortisol, progesterone, and testosterone. After 16 wk of cultivation of the stock culture in the presence of estradiol, the cells had acquired a distinct sensitivity to estradiol resulting in permanent growth enhancement. The withdrawal of cortisol from the medium of the stock culture subsequently provoked the loss of the initially noted stimulation of the proliferation by cortisol. The stimulatory effect of progesterone on the proliferation was reversed to inhibition when the stock culture was deprived of cortisol in the growth medium. The results indicate that the choice of steroid hormones in the stock culture medium was determining the quality of the cellular growth responses.

Blood↗
PubMed1983

Cell lines derived from human ovarian carcinomas: growth stimulation by gonadotropic and steroid hormones.

Carcinoma cell lines established from 5 patients with advanced tumors of ovarian location were characterized by karyotypes and growth properties in serum-free medium. In early passages of the cultivation, the growth of cell lines derived from tumors of fairly differentiated histology was stimulated by human follicle-stimulating hormone or human chorionic gonadotropin-human luteinizing hormone. Cells obtained from poorly differentiated carcinomas were unresponsive to gonadotropins. The proliferation of cell lines derived from a malignant clear cell carcinoma and from the ovarian metastasis of an advanced mammary carcinoma was enhanced by cortisol. The results imply that hormonal factors in concentrations physiologically occurring in human serum may support the in vivo growth of ovarian tumors.

Carcinoma↗