Biomedical subjects

M Darsow

Publications and source records attributed to M Darsow.

10 recordsLinked to original sources

PubMed2000

Long-term morbidity following axillary dissection in breast cancer patients--clinical assessment, significance for life quality and the impact of demographic, oncologic and therapeutic factors.

OBJECTIVE: This study describes in detail the surgery-related symptoms following axillary lymph node dissection in breast cancer patients and considers both their significance for long term quality of life and the impact of possible influencing factors. MATERIAL AND METHODS: Three hundred and ninety six patients were studied retrospectively using a self-report questionnaire and a clinical examination. The symptoms, numbness, pain, edema, arm strength and mobility were evaluated. The subjective assessment of the degree of symptom intensity was compared with objective measurements. The extent of surgery (number of resected nodes, level of dissection) as well as the influence of demographic, oncologic and adjuvant measures (age, time interval, number of involved nodes, chemotherapy) were evaluated. RESULTS: Shoulder-arm morbidity and fear of cancer recurrence were the most important long-term sources of distress following breast cancer surgery in our study population. Demographic, oncologic and therapeutic measures including the extent of surgery had no influence on long-term morbidity. The intensity of all evaluated symptoms was reported to be more severe in patients' subjective statements than in the results of clinical assessment. CONCLUSION: Shoulder-arm morbidity following axillary dissection is a frustrating polysymptomatic disease that seems to be relatively unaffected by therapeutic measures. The surgical trauma necessary for adequate tumor staging (removal of 10 lymph nodes) seems decisive for the postsurgery syndrome following axillary dissection. For node-positive patients complete axillary clearing may improve tumor control without worsening long-termmorbidity. New techniques, such as the sentinel-node-biopsy, that selects patients with negative axillary status while preserving the integrity of axillary structures, may improve the overall morbidity.

Adult↗

PubMed1999

Drug-induced apoptosis in chronic lymphocytic leukemia.

Glucocorticoids and fludarabine are able to induce typical features of apoptosis in CLL lymphocytes. Cysteinyl aspartate specific proteases (caspases) play a key biochemical role in the apoptotic pathway. Caspase activation following cytotoxic stimuli leads to highly specific proteolytic cleavage of functionally important cellular enzymes. One of them is poly ADP-ribose) polymerase (PARP). To some extent caspase activation seems to be under the control of the Bcl-2 family of interacting proteins. We determined the role of Bcl-2-family proteins Bcl-2 (anti-apoptotic) and Bax (pro-apoptotic), activation of caspase-3 (CPP32/Yama) and activation of PARP in CLL apoptosis. All 21 analyzed CLL samples expressed Bcl-2 and Bax. Four of 13 (31%) samples with a low Bcl-2/Bax ratio exhibited in vitro prednisolone resistance, whereas eight of nine (88%) samples with a high Bcl-2/Bax ratio were in vitro resistant (</=0.025). There was no significant correlation between clinical pre-treatment status and Bcl-2/Bax ratio. Caspase-3/CPP32 activity increase was registered after dexamethasone as well as after fludarabine treatment in CLL lymphocytes in vitro. Caspase inhibitor Z-VAD.fmk was only able to partially block dexamethasone-induced and spontaneous apoptosis but not fludarabine-induced apoptosis in CLL lymphocytes. PARP activity decreased after dexamethasone and fludarabine treatment. PARP inhibitor 3-aminobenzamide (3-AB) was able to partially inhibit dexamethasone-induced apoptosis but not fludarabine-induced and spontaneous apoptosis.

Aged↗

PubMed1996

Autoantibodies against p53 are not increased in human ascites and pleural effusions.

Mutated human p53 may give rise to the formation of autoantibodies and may be a marker for a worse prognosis. We speculated that ascites or pleural effusions may enhance the formation of such autoantibodies in cancer patients and, therefore, we measured the presence of autoantibodies in the ascites or pleural effusion of 40 patients with advanced malignancies. As controls, p53 autoantibodies were measured in 15 patients with effusions who did not have a malignancy. Using a specific enzyme-linked immunosorbent assay, p53 autoantibodies could only be detected in the effusions of 5/40 patients (12.5%) with known malignancies. The formation of autoantibodies did not correlate with the presence or absence of tumor cells in the effusion. The effusions of the patients without tumor were all negative for p53 autoantibodies. Our study shows that malignant or reactive effusions do not stimulate the local or systemic production of autoantibodies against p53.

Antibody Specificity↗

PubMed1996

Association of bcl-2, bax, bcl-xL and interleukin-1 beta-converting enzyme expression with initial response to chemotherapy in acute myeloid leukemia.

Bcl-2 expression is able to confer drug resistance to chemotherapy-induced programmed cell death. Bax, a partner protein of bcl-2 with extensive aminoacid homology, is a promoter of apoptosis. Apparently the equilibrium of bcl-2 and bax hetero- and homodimers is important for the susceptibility of cells for stimuli inducing apoptosis. In this study we determined the role of bcl-2 to bax expression ratio, bcl-xL and ICE expression level for predicting clinical response to chemotherapy in acute myelold leukemia (AML). Bone marrow samples from 14 patients with AML were examined using an immunophosphatase staining method. Initial bone marrow blast portion was over 80% in all cases. Clinical response was defined by bone marrow aspiration 4 weeks after treatment initiation. There was a significant correlation between bcl-2 to bax expression ratio and clinical response (P < 0.005). No patients with a bcl-2/bax ratio >1.0 achieved complete remission after induction therapy. No significant correlation between bcl-2- and p-glycoprotein-expression was observed in this group. Conversely a high expression of ICE indicated a good clinical response (P < 0.01), whereas expression of bcl-xL had no influence on therapeutic success in this group.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1994

[Expression of transforming growth factor beta-3 (TGF-beta-3) on reactive and malignant cells in ascites and pleural effusion].

PATIENTS AND METHOD: The expression of TGF-beta-3 was examined in 64 patients with reactive and malignant effusion by immunocytochemistry. RESULT: In about half of the patients with malignant effusions (especially breast cancer, gastric cancer, and carcinomas of unknown primary) TGF-beta positive tumor cells could be detected. We could show here for the first time that reactive mesothelial cells could also express TGF-beta. Lymphatic cells were negative in all cases. TGF-beta-3 bioactivity could also be detected in the effusions studied. In our group of patients with far advanced cancer, the expression of TGF-beta had no clear-cut clinical or prognostic correlate. However, the expression of TGF-beta on tumor cells should be interpreted as a marker of tumor progression, taking into account the fibrogenic, angiogenic and immunosuppressive properties of TGF-beta. CONCLUSION: Further research is necessary to answer the question if the 3 isoforms of TGF-beta are coordinately expressed and to elucidate the involvement of this cytokine in tumor progression and metastasis.

Adult↗

PubMed1993

Effects of tumor necrosis-factor on primary human leukemia cells: ultrastructural changes.

We investigated the ultrastructural effects of recombinant tumor necrosis factor alpha (TNF) on primary leukemia cells of 8 patients (4 cases of acute myelogenous leukemia and 4 cases of chronic myelogenous leukemia) as well as on bone marrow cells of 1 normal control. The cells were kept in liquid culture for up to 92 h in the presence of up to 10,000 U/ml of recombinant human TNF without adding colony-stimulating factors. Under these conditions the concentration of viable leukemic cells decreased by 14 to 53%, compared to control cultures. In acute myelogenous leukemia, all cases to some degree developed an enlargement of mitochondria; in 2 cases prominent cytoplasmic processes, and in 2 cases cytoplasmic vacuoles were observed. In chronic myelogenous leukemia, an enlargement and deformation of all cell types was observed to varying degrees. In the normal bone marrow sample only minor cytoplasmic changes occurred. In all cultures apoptotic changes were rarely observed and--if present--were observed also in cultures without TNF. When the DNA of leukemic cells treated with TNF was separated on agarose, no fragments characteristic of apoptosis were visible. Our results demonstrate that TNF does not induce direct cytotoxicity or apoptosis in acute or chronic myeloid leukemias and are compatible with the notion that some leukemic cells may be activated or stimulated by TNF. The mitochondrion appears to be one of the primary targets of TNF. Electron microscopy is useful for monitoring the changes induced by TNF.

Apoptosis↗

PubMed1992

TNF induces cytoplasmic vesicles in actinomycin D-treated K 562 cells.

We report here that tumor necrosis factor alpha (TNF) induces peculiar cytoplasmic vesicles in the human erythromyeloid leukemia cell line K 562, sensitized to the cytotoxic action of TNF by a treatment with the inhibitor of transcription actinomycin D. These vesicles are well delineated ultrastructurally. The formation of these vesicles is characteristic for the combination of actinomycin D with TNF and precedes the changes of apoptosis and cellular disintegration. These vesicles correspond to an intermediate step in the cytotoxicity caused by TNF and may indicate that reactive metabolites are involved in the mechanism of action of TNF.

Cell Division↗

PubMed1984

Mitochondrial changes in malignant lymphoma cells.

Mitochondrial changes (enlargement, loss of cristae, finely granular content) were observed in 5-25% of the lymphoma cells of 6 patients suffering from different types of non-Hodgkin's lymphomas. These cytoplasmic inclusions may also be visible in light microscopic preparations and may give reason for misinterpretation.

Bone Marrow↗

PubMedDate not supplied

P53-immunoreactive cells in benign and malignant effusions: diagnostic value using a panel of monoclonal antibodies and comparison with CEA-staining.

The diagnosis of malignancy in peritoneal and pleural effusions can be difficult, because activated mesothelial cells may resemble malignant cells. P53 mutations are the most frequent genetic changes in human cancer and translate into an overexpression of the p53 protein detectable by immunocytochemistry. In this study, we investigated the sensitivity and specificity of 4 different monoclonal antibodies (moAB) against p53 for the diagnosis of malignancy in effusions. We also compared p53 staining with CEA immunocytochemistry which previous work had established as a specific marker of malignancy in body cavity effusions. Normal and malignant cells from 28 benign and 52 malignant effusions (pleura and ascites) were examined by indirect immuno-alkaline phosphatase method. Four different moAB against p53 (PAB 1801, PAB 240, DO-1 and DO-7) and one moAB against CEA (CEA-84) were used. Antibodies p1801, p240 and DO-1 react with 52-75% of cases of effusions with malignant cells, but also with 38-80% of benign effusions. Only the antibody DO-7 and the CEA moAB show specificity for malignant cells reacting respectively with 20 (55%) of cases. A combination of these 2 markers does not enhance the sensitivity for the detection of tumor cells. No direct correlation between CEA and p53 immunostaining could be established. The sensitivity and specificity of staining p53 in malignant cells by immunocytochemistry depend strongly on the antibody used. Some p53 moAB are positive with reactive cells in ascites and pleural effusions. Currently, p53 staining of expressing cells does not improve the identification of malignant cells in comparison with CEA immunocytochemistry, but may help to screen for patients with p53 mutations.

Antibodies, Monoclonal↗

PubMedDate not supplied

Value of human chorionic gonadotropin compared to CEA in discriminating benign from malignant effusions.

Human chorionic gonadotropin (HCG) is expressed in germ cell tumors and urothelial, breast, lung and colon cancers. The aim of the study was to investigate if the determination of HCG in comparison with CEA is able to discriminate between malignant and benign effusions. Effusion and partially serum samples of 61 patients with benign (g.i., heart/kidney isnuff.) and 116 patients with malignant diseases (g.i., gynec., lung, misc., CUP) were investigated. HCG was specifically determined by an IRMA using 2 monoclonal antibodies, CEA by a conventional double Ab RIA. Cytological staining was preformed using the Pappenheim-method on cytospin preparations. Significant differences (p < 0.001) were found for HCG between benign and malignant ascitic effusions with the best discrimination at 5 IU/l (ROC) and an overall sensitivity of 31.3% (spec. vs benign eff. 93.4%) increasing in subgroups from hematol. (5.8%) < misc. (31.3%) < gynec. (32.1%) < g.i. (36%) < lung (38.1%) to CUP (50%). CEA also showed significant differences between benign and malignant total and ascitic effusions, and weaker for the pleural subgroup (cutoff 9 ng/ml) with a total sensitivity of 44.6% (sp = 100%) increasing from misc. (30.8%) < lung (47.1%) < CUP (50%) < gynec. (60%) < g.i. (60.9%). Comparative cytology and TM determinations increased the positiverate of cytology (45.2%) to 58.3% for either cytology or HCG positive cases, or to 61.6% for either cytology or CEA positive cases. For the combined determination of cytologoy and HCG and CEA, the overall TM positive rate for 33 cytology-pos. cases was 78.8%, but in 40 cytology-negative cases 37.5% for TM positive cases. In conclusion HCG is useful in ascitic > pleural effusions with high specificity (90% at 5 IU/l) but low sensitivity of 31% increasing in g.i., lung and gynecologic cases, CEA a more general TM with higher sensitivity of 45% increasing in g.i., gynecologic and lung cases (sp. 100% at 9 ng/ml) both adding significantly to cytology-negative effusions.

Biomarkers, Tumor↗