Daniela Trog

Risk assessment, disease prevention and personalised treatments in breast cancer: is clinically qualified integrative approach in the horizon?

Breast cancer is a multifactorial disease. A spectrum of internal and external factors contributes to the disease promotion such as a genetic predisposition, chronic inflammatory processes, exposure to toxic compounds, abundant stress factors, a shift-worker job, etc. The cumulative effects lead to high incidence of breast cancer in populations worldwide. Breast cancer in the USA is currently registered with the highest incidence rates amongst all cancer related patient cohorts. Currently applied diagnostic approaches are frequently unable to recognise early stages in tumour development that impairs individual outcomes. Early diagnosis has been demonstrated to be highly beneficial for significantly enhanced therapy efficacy and possibly full recovery. Actual paper shows that the elaboration of an integrative diagnostic approach combining several levels of examinations creates a robust platform for the reliable risk assessment, targeted preventive measures and more effective treatments tailored to the person in the overall task of breast cancer management. The levels of examinations are proposed, and innovative technological approaches are described in the paper. The absolute necessity to create individual patient profiles and extended medical records is justified for the utilising by routine medical services. Expert recommendations are provided to promote further developments in the field.

Expression of ABC-1 transporter is elevated in human glioma cells under irradiation and temozolomide treatment

Summary.Objective: Chemo-therapeutic treatment of glioma patients has minor success. Little is known about mechanisms of a pronounced resistance of gliomas towards actual therapies, yet. ABC-1 belongs to the group of transporters known to be involved in the export of hydrophobic substances and vascular regulation. This study investigates an effect of both temozolomide (TMZ) treatment and/or irradiation on the expression of the ABC-1 transporter in human U87-MG glioma cells.Material and methods: In parallel experiments U87-MG cells underwent either irradiation (RT), chemo-treatment (CT) using TMZ, and combined chemo/radiation-treatment (CT/RT). After each treatment the cells were incubated either 2 or 24 hours at 37°C and counted before protein analysis using Western-Blot technique.Results and conclusions: An exponential growth of cellular density was observed for both untreated and irradiated cells being, however, about 2-times slower in irradiated compared to untreated cells. In contrast the density increase of chemo-treated cells as well as that of cells, which underwent the combined CT/RT treatment was of linear nature. ABC-1 expression was detected in untreated as well as treated cells. Increasing cell density and all kinds of treatment resulted in a considerably enhanced ABC-1 expression. CT treatment resulted in highly up-regulated ABC-1 expression especially in non-confluent cultures compared to untreated cells. Irradiation had a comparable or even higher inducible effect on the ABC-1 expression rates depending, however, on cell density. The highest expression rates were observed in cultures with high cellular density 2 hours after application of the combined treatment. Strong up-regulation of ABC-1 expression under both irradiation and chemo-treatment might be a clue to multidrug and irradiation cross-resistance mechanisms of malignant glioma cells converting the ABC-1 transporter into an attractive pharmacological target for a clinical breakthrough in the therapy of malignant gliomas.

Up-regulation of vimentin expression in low-density malignant glioma cells as immediate and late effects under irradiation and temozolomide treatment

Nervous system tumors are one of the leading causes of cancer related death. Specific mechanisms facilitating the invasive behavior of gliomas remain obscure. Advanced simulation models of the in vivo response to therapy conditions should potentially improve malignant glioma treatment. Expressional profiling of vimentin––one of reliable pro-invasive tumor makers––in those simulation models was the goal of this study, in order to estimate a pro-invasive response of surviving malignant glioma cells under clinically relevant therapeutic conditions. Human U87-MG malignant glioma cells were used. These cells are characterized by the wild p53-phenotype, which is relevant for the majority of primary malignant glioblastomas. Experimental design foresaw the cells to undergo either irradiation or chemo-treatment with temozolomide alone, or combined treatment. Expression profiling of vimentin was performed by quantitative “Real-Time”-PCR under all treatment conditions simulating diverse tumor regions. Here we demonstrated that vimentin expression patterns in human malignant glioma cells strongly depend on cellular density, algorithms of drug delivery and chemo/radio treatment. Substantial differences were recognized between immediate and late therapy effects. Significant increase in vimentin expression levels was detected particularly in low-density cell cultures under durable treatment with constant concentration levels of temezolomide. Simulation of variable intratumoral regional conditions (central intratumoral regions vs. disseminated malignant cells in peripheral regions) demonstrated differential response of vimentin expression in malignant glioma cell cultures treated under clinically relevant conditions. Slight ebbing of expression levels as late effects of the treatment in confluent cultures may correspond to necrotic processes clinically observed in central intratumoral regions. Contrary, in disseminated malignant cells of peripheral regions therapy resulted in vimentin-inducing effects. This is in agreement with the clinical observations of an increased aggressiveness and malignancy grade of post-operatively chemo/radio-treated malignant gliomas.

Molecular imaging system for possible prediction of active retinopathy in patients with Diabetes mellitus

Summary.Objective: The deposition of advanced glycation end products is enhanced in Diabetes mellitus (DM) and has been linked to diabetic complications such as a microvascular disease. Glycated proteins have receptors on mononuclear blood cells (MBCs) and have been shown to generate reactive oxygen species altering gene expression and modifying cellular targets, such as endothelial cells. Retinal angiopathy is a frequently observed microvascular complication in DM-patients. Because of the central role of activated MBCs, we hypothesised a functional link between specific alterations in gene expression of MBCs, an increased activity of matrix proteases in serum, and the extent of retinal angiopathy in DM.Material and methods: An appearance and proliferation index of diabetic retinopathy was evaluated in 38 DM-patients using fluorescein angiography. Alterations of gene transcription levels in MBCs were investigated using hybridisation of individual mRNA-pools to Atlas Array with a concomitant quantification of specific cDNAs by “Real-Time”-PCR. The activity of matrix metalloproteinases MMP-2 and MMP-9 in individual serum samples was measured by zymography combined with densitometric imaging system.Results and conclusions: Hybridisation to Atlas Array of mRNA-pools isolated from MBCs revealed an enhanced expression of recoverin in DM-patients compared to the control group. “Real-Time”-PCR showed the highest recoverin levels in the DM-subgroup with a high proliferation index. MMP-2 activity was highly increased in 36% of all patients, and in 44, 44, and 19% of patients with proliferative retinopathy, advanced proliferative retinopathy, and no detectable proliferation respectively. In those 3 groups MMP-9 activity was highly increased in 56, 67, and 31% of patients respectively, and in 44% of all DM-patients. In contrast to patients with active proliferation, the simultaneous high activation of all three genes was not observed in patients without active proliferation. The ex vivo molecular imaging system developed in this work may be helpful for the prediction of active proliferative retinopathy in DM.

Non-sufficient cell cycle control as possible clue for the resistance of human malignant glioma cells to clinically relevant treatment conditions

Summary.Objectives. Human gliomas have a catastrophic prognosis with a median survival in the range of one year even after therapeutic treatment. Relatively high resistance towards apoptotic stimuli is the characteristic feature of malignant gliomas. Since cell cycle control has been shown to be the key mechanism controlling both apoptosis and proliferation, this study focuses on DNA damage analysis and protein expression patterns of essential cell cycle regulators P53 and P21waf1/cip1 in glioma under clinically relevant therapeutic conditions. Material and methods. U87MG cell line, characterised by wild p53-phenotype relevant for the majority of primary malignant glioblastomas, was used. Glioma cells underwent either irradiation or temozolomide treatment alone, or combined radio/chemo treatment. DNA damage was analysed by the “Comet Assay”. Expression rates of target proteins were analysed using “Western-Blot” technique. Results and conclusions. “Comet Assay” demonstrated extensive DNA damage caused by temozolomide treatment alone and in combination with irradiation, correlating well with the low survival rate observed under these treatment conditions. In contrast, irradiation alone resulted in a relatively low DNA damage, correlating well with a high survival rate and indicating a poor therapeutic efficiency of irradiation alone. Unusually low up-regulation of P53 and P21waf1/cip1 expression patterns was produced by the hereby tested stressful conditions. A deficit in cell cycle control might be the clue to the high resistance of malignant glioma cells to established therapeutic approaches.

Volumetric changes of the breast during radiotherapy. Is a replanning necessary for the electron boost

Hintergrund und Ziel:Eine Radiotherapie der Mamma induziert eine Gewebereaktion mit daraus resultierendem Ödem. Dieses Ödem führt zu einer Volumenzunahme der Mamma. Ziel der Studie war es, diese Volumenzunahme zu quantifizieren und deren Einfluss auf die Planung des Elektronenboosts zu analysieren.Patienten und Methodik:Bei 140 Patientinnen mit Mammakarzinom nach brusterhaltender Therapie erfolgte vor, während und/oder nach der Bestrahlung eine CT-Planung, um die Volumenveränderungen während der Bestrahlung zu evaluieren. Die ermittelten CT-Daten wurden unter Verwendung des HELAX-TMS-Planungssystems zur Bestimmung der Dosisverteilung ausgewertet. Die Bestimmung des Brustvolumens erfolgte mittels Interpolationsalgorithmus. Gemessen am Ausgangsvolumen wurden die Patientinnen in drei Subgruppen unterteilt: Gruppe 1 (n = 47): ≤ 670 cm3, Gruppe 2 (n = 46): 671–999 cm3 und Gruppe 3 (n = 47): ≥ 1 000 cm3 Brustvolumen.Ergebnisse:Initial zeigte sich ein mittleres Brustvolumen von 907 cm3 (100–3 073 cm3). Nach Radiotherapie kam es zu einem Anstieg des Brustvolumens um durchschnittlich 81 cm3 auf 988 cm3 (109–3 185 cm3). Signifikant messbare Volumenzunahmen traten ab einer Zielvolumendosis von 40 Gy auf. Bezogen auf die drei Subgruppen ergaben sich folgende mittlere Volumenzunahmen: Gruppe 1: 53 cm3 (3–120 cm3), Gruppe 2: 85 cm3 (20–200 cm3) und Gruppe 3: 105 cm3 (5–340 cm3). Der Zuwachs war in allen drei Gruppen mit einem p-Wert von p < 0,001 hochsignifikant. Je nach Volumenzunahme der Brust resultierte eine Änderung der Herdtiefe um bis zu 1,0 cm.Schlussfolgerung:Aufgrund der interkurrenten Volumenänderungen unter Bestrahlung erscheint eine zweite CT-Untersuchung zur Nachplanung vor Boostbestrahlung sinnvoll. Die zweite CT-Planung sollte ab 40 Gy erfolgen, um das Ödem ausreichend erfassen zu können.Background and Purpose:Radiotherapy can induce tissue reactions with an edema leading to increased breast volume. The aim of the present study was to quantify this increase and analyze its effect on the electron boost technique.Patients and Methods:140 patients with breast cancer treated with breast-conserving surgery underwent CT planning before, during and/or after radiotherapy in order to evaluate breast volume changes due to radiotherapy. CT data were analyzed using the HELAX planning system and dose distribution was assessed. Determination of the breast volume was achieved using an interpolation algorithm. Three subgroups were analyzed: group 1 (n = 47): ≤ 670 cm3, group 2 (n = 46): 671–999 cm3, and group 3 (n = 47): ≥ 1000 cm3 breast volume.Results:The mean initial breast volume was 907 cm3 (100–3073 cm3). After radiotherapy, mean breast volume increased by 81 cm3 to 988 cm3 (109–3185 cm3). Significant changes in volume were observed after a dose of 40 Gy. According to the subgroups mean volume increase was as follows: group 1: 53 cm3 (3–120 cm3), group 2: 85 cm3 (20–200 cm3), and group 3: 105 cm3 (5–340 cm3). This difference was statistically significant for all subgroups (p < 0.001). Corresponding to the volume increase, depth of the boost target volume changed up to 1.0 cm.Conclusion:As radiotherapy may lead to a significant increase in breast volume, it seems appropriate to perform a second planning CT after about 40 Gy in order to optimize dose distribution for boost irradiation.

Volumetrische Veränderungen der Mamma während der Radiotherapie

Hintergrund und Ziel:Eine Radiotherapie der Mamma induziert eine Gewebereaktion mit daraus resultierendem Ödem. Dieses Ödem führt zu einer Volumenzunahme der Mamma. Ziel der Studie war es, diese Volumenzunahme zu quantifizieren und deren Einfluss auf die Planung des Elektronenboosts zu analysieren.Patienten und Methodik:Bei 140 Patientinnen mit Mammakarzinom nach brusterhaltender Therapie erfolgte vor, während und/oder nach der Bestrahlung eine CT-Planung, um die Volumenveränderungen während der Bestrahlung zu evaluieren. Die ermittelten CT-Daten wurden unter Verwendung des HELAX-TMS-Planungssystems zur Bestimmung der Dosisverteilung ausgewertet. Die Bestimmung des Brustvolumens erfolgte mittels Interpolationsalgorithmus. Gemessen am Ausgangsvolumen wurden die Patientinnen in drei Subgruppen unterteilt: Gruppe 1 (n = 47): ≤ 670 cm3, Gruppe 2 (n = 46): 671–999 cm3 und Gruppe 3 (n = 47): ≥ 1 000 cm3 Brustvolumen.Ergebnisse:Initial zeigte sich ein mittleres Brustvolumen von 907 cm3 (100–3 073 cm3). Nach Radiotherapie kam es zu einem Anstieg des Brustvolumens um durchschnittlich 81 cm3 auf 988 cm3 (109–3 185 cm3). Signifikant messbare Volumenzunahmen traten ab einer Zielvolumendosis von 40 Gy auf. Bezogen auf die drei Subgruppen ergaben sich folgende mittlere Volumenzunahmen: Gruppe 1: 53 cm3 (3–120 cm3), Gruppe 2: 85 cm3 (20–200 cm3) und Gruppe 3: 105 cm3 (5–340 cm3). Der Zuwachs war in allen drei Gruppen mit einem p-Wert von p < 0,001 hochsignifikant. Je nach Volumenzunahme der Brust resultierte eine Änderung der Herdtiefe um bis zu 1,0 cm.Schlussfolgerung:Aufgrund der interkurrenten Volumenänderungen unter Bestrahlung erscheint eine zweite CT-Untersuchung zur Nachplanung vor Boostbestrahlung sinnvoll. Die zweite CT-Planung sollte ab 40 Gy erfolgen, um das Ödem ausreichend erfassen zu können.Background and Purpose:Radiotherapy can induce tissue reactions with an edema leading to increased breast volume. The aim of the present study was to quantify this increase and analyze its effect on the electron boost technique.Patients and Methods:140 patients with breast cancer treated with breast-conserving surgery underwent CT planning before, during and/or after radiotherapy in order to evaluate breast volume changes due to radiotherapy. CT data were analyzed using the HELAX planning system and dose distribution was assessed. Determination of the breast volume was achieved using an interpolation algorithm. Three subgroups were analyzed: group 1 (n = 47): ≤ 670 cm3, group 2 (n = 46): 671–999 cm3, and group 3 (n = 47): ≥ 1000 cm3 breast volume.Results:The mean initial breast volume was 907 cm3 (100–3073 cm3). After radiotherapy, mean breast volume increased by 81 cm3 to 988 cm3 (109–3185 cm3). Significant changes in volume were observed after a dose of 40 Gy. According to the subgroups mean volume increase was as follows: group 1: 53 cm3 (3–120 cm3), group 2: 85 cm3 (20–200 cm3), and group 3: 105 cm3 (5–340 cm3). This difference was statistically significant for all subgroups (p < 0.001). Corresponding to the volume increase, depth of the boost target volume changed up to 1.0 cm.Conclusion:As radiotherapy may lead to a significant increase in breast volume, it seems appropriate to perform a second planning CT after about 40 Gy in order to optimize dose distribution for boost irradiation.