Biomedical subjects

D Marx

Publications and source records attributed to D Marx.

131 records · Page 8Linked to original sources

PubMedDate not supplied

Hormonal treatment with sex steroids in women is associated with lower p105 serum concentrations.

BACKGROUND: In breast and ovarian cancer patients elevated serum levels of the oncoprotein p105 were detected. We examined the influence of endocrine factors on the p105 serum concentration. MATERIALS AND METHODS: The sera of 115 and non-pregnant women were analysed. Of the premenopausal women (n = 77) hormonal contraception was used by 30 women, and of the postmenopausal women (n = 33) there were 15 women using hormonal replacement therapy (HRT). The serum specimens were analysed by ELISA. RESULTS: Women with hormonal contraception had significantly lower serum levels than premenospausal controls (82-138 fmol/ml, median 109 fmol/ml vs. 103-183 fmol/ml, median 130 fmol/ml; P < 0.001). In postmenopausal women with HRT serum levels were significantly lower than in postmenopausal controls (88-136 fmol/ml, median 117 fmol/ml vs. 99-261 fmol/ml, median 148 fmol/ml; P < 0.001). CONCLUSIONS: Sex steroids seem to modulate c-erbB-2 activity. These results are important with regard to clinical studies on p105 oncoprotein in cancer patients.

Contraceptives, Oral, Hormonal↗

PubMedDate not supplied

Deregulated simultaneous expression of multiple glucose transporter isoforms in malignant cells and tissues.

To evaluate the molecular and functional characteristics of upregulated glucose uptake in malignant cells, the expression of four glucose transporter (Glut) isoforms as well as glucose transport were determined in benign and malignant cell lines and tissues. In vivo distribution of Glut proteins was examined by immunocytochemistry in 30 breast cancer samples. In comparison with benign controls upregulation of Glut 1 mRNA and Glut 3 mRNA was shown. Glut 2 mRNA could not be detected. Glut 4 mRNA was found in various malignant cell lines in contrast to the physiological restriction of Glut 4 to terminally differentiated muscle and fat cells. While Glut 3 protein was not detectable in non-neuronal tissues, the degree of overexpression of Glut 1 and 4 corresponded to the expression level of the respective mRNAs. 57% of the breast cancer tissues showed positivity for Glut 1, 43% for Glut 4. Functional integrity of Glut 4 was demonstrated by preserved insulin-responsiveness. In cell lines, glucose transport activity was positively correlated with proliferation rate. Enhanced translocation of Glut 4 to the plasma membrane in correlation with high Ki-67 positivity in tissues pointed to the same association in vivo. C-myc overexpression had no detectable influence on Glut expression. In conclusion, malignant cells demonstrate quantitative as well qualitative changes of Glut expression and activity. Alteration of differentiation-adapted transcription and expression of cell-specific Gluts may represent a part of the transformation process and contribute to tumor progression.

Adult↗

PubMedDate not supplied

Breast preserving surgery decision making.

Mammography, and in special cases MRT, allow the detection of DCIS and microcarcinomas. Breast preserving surgery needs intraoperative care for tumor free margins. Decision making under favourable and unfavourable conditions is discussed. Tumor grading is important with respect to locoregional recurrences. Improvements in breast cancer diagnosis are discussed in a separate paper in the same volume. The significance of c-erbB2 in pT1N0M0 stage has been determined in 472 cases. Within the c-erbB family, c-erbB2 has highest significance. p53 should also be evaluated with respect to tumor progress. In a few cases of malignant cystosarcoma phyllodes, p53 reaction was found in epithelial and mesenchymal cell systems. These results correspond to the results of Domagala et al (90) which show that vimentin positivity correlates with high proliferation, a high degree of malignancy and c-erbB2 positivity. Finally, the significance of angiogenesis with respect to the ineffective knot-formation for tumor cell transport and detachment of epithelia with apoptosis are discussed. The significance of proteolytic activity of cancer according to the results of Schmitt et al (89) is included in the discussion. Biochemical analysis seems to be much more effective for prediction of metastatic process as compared with immunohistochemical evaluations.

Breast Neoplasms↗

PubMedDate not supplied

Detection of p105 (c-erbB-2, HER2/neu) serum levels by a new ELISA in patients with ovarian carcinoma.

BACKGROUND: Immunohistochemical detection of the oncogene c-erbB-2 (HER2/neu) has been shown to be an important prognostic marker in ovarian cancer. In this study we evaluated a new developed polyclonal detector antibody-based ELISA for the extracellular domain of p185 to determine whether the soluble oncoprotein fragment p105 can be detected in the serum of ovarian cancer patients. MATERIALS AND METHODS: The relationship between p105 serum levels and various tumor parameters in 53 patients with newly diagnosed, untreated ovarian cancer was studied. Serum specimens were obtained prior initial surgery, and p105 levels were determined using a new developed, polyclonal detector antibody-based human neu quantitative ELISA assay. RESULTS: Using the polyclonal detector antibody-based ELISA, elevated p105 serum levels were not related to tumor stage, grade, histology and residual tumor after primary surgery. CONCLUSIONS: These results suggest that particular statements concerning the preoperatively taken p105 level using the polyclonal antibody-based ELISA in patients with primary ovarian cancer cannot be brawn yet.

Adult↗

PubMedDate not supplied

Co-expression of the MDR1 gene and HSP27 in human ovarian cancer.

Heat-shock proteins seem to play a still undefined role in cancer. One of them particularly, the low molecular weight HSP27, seems to be involved in resistance to chemotherapy. This phenomenon has been reported in breast cancer cell lines, and the aim of this study was to investigate if it also takes place in clinical tumour samples from ovarian cancer patients. We studied ovarian carcinoma samples from 95 patients by means of immunohistochemistry for the overexpression of both the product of the multidrug-resistance gene (P-glycoprotein) and HSP27. The expression of the MDR1 gene in more than 50% of the tumour cells was associated with an almost significantly shorter survival of patients with stage II, III and IV tumours (p = 0.05), although intriguingly not with the response to chemotherapy. Tumours expressing the MDR1 gene, furthermore, also tended to co-express HSP27 (64.9% vs. 42.1%), and this difference was statistically significant (p = 0.026).

ATP Binding Cassette Transporter, Subfamily B, Mem↗