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44 result(s) for "Dienemann, H."
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Randomized study on early detection of lung cancer with MSCT in Germany: study design and results of the first screening round
Purpose Low-dose multislice-CT (MSCT) detects many early-stage lung cancers with good prognosis, but whether it decreases lung cancer mortality and at which costs is yet insufficiently explored. Scope of the present study is to examine within a common European effort whether MSCT screening is capable to reduce the lung cancer mortality by at least 20 % and at which amount of undesired side effects this could be achieved. Methods Overall 4,052 heavy smoking men and women were recruited by a population-based approach and randomized into a screening arm with five annual MSCT screens and an initial quit-smoking counseling, and a control arm with initial quit-smoking counseling and five annual questionnaire inquiries. Results In the first screening round, 2,029 participants received a MSCT providing 1,488 negative and 540 suspicious screens with early recalls (early recall rate 26.6 %) leading to 31 biopsies (biopsy rate 1.5 %) and 22 confirmed lung cancers (detection rate 1.1 %). Among the lung cancers, 15 were adenocarcinomas, 3 squamous cell carcinomas, one small-cell lung cancer, and 3 others, whereby 18 were in clinical stage I, one in stage II, and 3 in stage III. One interval cancer occurred. Conclusions The indicated performance indicators fit into the range observed in comparable trials. The study continues finalizing the second screening round and for the first participants even the last screening round. The unresolved issue of the precise amount of side effects and the high early recall rate precludes currently the recommendation of MSCT as screening tool for lung cancer.
Tumour cell proliferation (Ki-67) in non-small cell lung cancer: a critical reappraisal of its prognostic role
Background: Uncontrolled proliferation is a hallmark of malignant tumour growth. Its prognostic role in non-small cell lung cancer (NSCLC) has been investigated in numerous studies with controversial results. We aimed to resolve these controversies by assessing the Ki-67 proliferation index (PI) in three large, independent NSCLC cohorts. Methods: Proliferation index was retrospectively analysed by immunohistochemistry in a cohort of 1065 NSCLC and correlated with clinicopathological data including outcome and therapy. Results were validated in two independent cohorts of 233 squamous cell carcinomas (SQCC) and 184 adenocarcinomas (ADC). Results: Proliferation index (overall mean: 40.7%) differed significantly according to histologic subtypes with SQCC showing a mean PI (52.8%) twice as high as ADC (25.8%). In ADC PI was tightly linked to growth patterns. In SQCC and ADC opposing effects of PI on overall (OS), disease-specific and disease-free survival were evident, in ADC high PI (optimised validated cut-off: 25%) was a stage-independent negative prognosticator (hazard ratio, HR OS: 1.56, P =0.004). This prognostic effect was largely attenuated by adjuvant radio-/chemotherapy. In SQCC high PI (optimised validated cut-off: 50%) was associated with better survival (HR OS: 0.65, P =0.007). Conclusions: Our data demonstrate that PI is a clinically meaningful biomarker in NSCLC with entity-dependent cut-off values that allow reliable estimation of prognosis and may potentially stratify ADC patients for the need of adjuvant therapy.
Epigenetic screen identifies genotype-specific promoter DNA methylation and oncogenic potential of CHRNB4
Genome-wide association studies have highlighted three major lung cancer susceptibility regions at 15q25.1, 5p15.33 and 6p21.33. To gain insight into the possible mechanistic relevance of the genes in these regions, we investigated the regulation of candidate susceptibility gene expression by epigenetic alterations in healthy and lung tumor tissues. For genes up or downregulated in lung tumors, the influence of genetic variants on DNA methylation was investigated and in vitro studies were performed. We analyzed 394 CpG units within 19 CpG islands in the susceptibility regions in a screening set of 34 patients. Significant findings were validated in an independent patient set ( n =50) with available DNA and RNA. The most consistent overall DNA methylation difference between tumor and adjacent normal tissue on 15q25 was tumor hypomethylation in the promoter region of CHRNB4 with a median difference of 8% ( P <0.001), which resulted in overexpression of the transcript in tumors ( P <0.001). Confirming previous studies, we also found hypermethylation in CHRNA3 and telomerase reverse transcriptase ( TERT ) with significant expression changes. Decitabine treatment of H1299 cells resulted in reduced methylation levels in gene promoters, elevated transcript levels of CHRNB4 and CHRNA3 , and a slight downregulation of TERT demonstrating epigenetic regulation of lung cancer cells. Single-nucleotide polymorphisms rs421629 on 5p15.33 and rs1948, rs660652, rs8040868 and rs2036527 on 15q25.1, previously identified as lung cancer risk or nicotine-addiction modifiers, were associated with tumor DNA methylation levels in the promoters of TERT and CHRNB4 ( P <0.001), respectively, in two independent sample sets ( n =82; n =150). In addition, CHRNB4 knockdown in two different cell lines (A549 and H1299) resulted in reduced proliferation ( P A549 <0.05; P H1299 <0.001) and propensity to form colonies in H1299 cells. These results suggest epigenetic deregulation of nicotinic acetylcholine receptor subunit ( nAChR ) genes which in the case of CHRNB4 is strongly associated with genetic lung cancer susceptibility variants and a functional impact on tumorigenic potential.
Tumour-site-dependent expression profile of angiogenic factors in tumour-associated stroma of primary colorectal cancer and metastases
Background: Tumour-associated stroma has a critical role in tumour proliferation. Our aim was to determine a specific protein expression profile of stromal angiogenic cytokines and matrix metalloproteinases (MMPs) to identify potential biomarkers or new therapy targets. Methods: Frozen tissue of primary colorectal cancer ( n =25), liver ( n =25) and lung metastases ( n =23) was laser-microdissected to obtain tumour epithelial cells and adjacent tumour-associated stroma. Protein expression of nine angiogenic cytokines and eight MMPs was analysed using a multiplex-based protein assay. Results: We found a differential expression of several MMPs and angiogenic cytokines in tumour cells compared with adjacent tumour stroma. Cluster analysis displayed a tumour-site-dependent stromal expression of MMPs and angiogenic cytokines. Univariate analysis identified stromal MMP-2 and MMP-3 in primary colorectal cancer, stromal MMP-1, -2, -3 and Angiopoietin-2 in lung metastases and stromal MMP-12 and VEGF in liver metastases as prognostic markers ( P >0.05, respectively). Furthermore, stroma-derived Angiopoietin-2 proved to be an independent prognostic marker in colorectal lung metastases. Conclusion: Expression of MMPs and angiogenic cytokines in tumour cells and adjacent tumour stroma is dependent on the tumour site. Stroma-derived MMPs and angiogenic cytokines may be useful prognostic biomarkers. These data can be helpful to identify new agents for a targeted therapy in patients with colorectal cancer.
Expression ratio of the TGFβ-inducible gene MYO10 is prognostic for overall survival of squamous cell lung cancer patients and predicts chemotherapy response
In lung cancer a deregulation of Transforming Growth Factor-β (TGFβ) signaling has been observed. Yet, the impact of TGFβ in squamous cell carcinoma of the lung (LUSC) remained to be determined. We combined phenotypic and transcriptome-wide studies and showed that the stimulation of the LUSC cell line SK-MES1 with TGFβ results in an increase of migratory invasive properties. The analysis of the dynamics of gene expression by next-generation sequencing revealed that TGFβ stimulation orchestrates the upregulation of numerous motility- and actin cytoskeleton-related genes. Among these the non-muscle myosin 10 ( MYO10 ) showed the highest upregulation in a LUSC patient cohort of the Cancer Genome Atlas (TCGA). Knockdown of MYO10 abrogated TGFβ-induced collagen gel invasion of SK-MES1 cells. The analysis of MYO10 mRNA expression in paired tissues of 151 LUSC patients with corresponding 80-month clinical follow-up data showed that the mRNA expression ratio of MYO10 in tumor and tumor-free tissue is prognostic for overall survival of LUSC patients and predictive for the response of these patients to adjuvant chemotherapy. Thus, MYO10 represents a new clinical biomarker for this aggressive disease and due to its role in cellular motility and invasion could serve as a potential molecular target for therapeutic interventions in patients with LUSC.
Simultaneous Computed Tomography-Guided Biopsy and Radiofrequency Ablation of Solitary Pulmonary Malignancy in High-Risk Patients
Background: In recent years experience has been accumulated in percutaneous radiofrequency ablation (RFA) of lung malignancies in nonsurgical patients. Objectives: In this study, we retrospectively evaluated a simultaneous diagnostic and therapeutic approach including CT-guided biopsy followed immediately by RFA of solitary malignant pulmonary lesions. Methods: CT-guided transthoracic core needle biopsy of solitary pulmonary lesions suspicious for malignancy was performed and histology was proven based on immediate frozen sections. RFA probes were placed into the pulmonary tumors under CT guidance and the ablation was performed subsequently. The procedure-related morbidity was analyzed. Follow-up included a CT scan and pulmonary function parameters. Results: A total of 33 CT-guided biopsies and subsequent RFA within a single procedure were performed. Morbidity of CT-guided biopsy included pulmonary hemorrhage (24%) and a mild pneumothorax (12%) without need for further interventions. The RFA procedure was not aggravated by the previous biopsy. The rate of pneumothorax requiring chest tube following RFA was 21%. Local tumor control was achieved in 77% with a median follow-up of 12 months. The morbidity of the CT-guided biopsy had no statistical impact on the local recurrence rate. Conclusions: The simultaneous diagnostic and therapeutic approach including CT-guided biopsy followed immediately by RFA of solitary malignant pulmonary lesions is a safe procedure. The potential of this combined approach is to avoid unnecessary therapies and to perform adequate therapies based on histology. Taking the local control rate into account, this approach should only be performed in those patients who are unable to undergo or who refuse surgery.
Dexamethasone-induced cisplatin and gemcitabine resistance in lung carcinoma samples treated ex vivo
Chemotherapy for lung cancer not only has severe side effects but frequently also exhibits limited, if any clinical effectiveness. Dexamethasone (DEX) and similar glucocorticoids (GCs) such as prednisone are often used in the clinical setting, for example, as cotreatment to prevent nausea and other symptoms. Clinical trials evaluating the impact of GCs on tumour control and patient survival of lung carcinoma have never been performed. Therefore, we isolated cancer cells from resected lung tumour specimens and treated them with cisplatin in the presence or absence of DEX. Cell number of viable and dead cells was evaluated by trypan blue exclusion and viability was measured by the MTT-assay. We found that DEX induced resistance toward cisplatin in all of 10 examined tumour samples. Similar results were found using gemcitabine as cytotoxic drug. Survival of drug-treated lung carcinoma cells in the presence of DEX was longlasting as examined 2 and 3 weeks after cisplatin treatment of a lung carcinoma cell line. These data corroborate recent in vitro and in vivo xenograft findings and rise additional concerns about the widespread combined use of DEX with antineoplastic drugs in the clinical management of patients with lung cancer.
Epigenetic screen identifies genotype-specific promoter DNA methylation and oncogenic potential of CHRNB4
Genome-wide association studies have highlighted three major lung cancer susceptibility regions at 15q25.1, 5p15.33 and 6p21.33. To gain insight into the possible mechanistic relevance of the genes in these regions, we investigated the regulation of candidate susceptibility gene expression by epigenetic alterations in healthy and lung tumor tissues. For genes up or downregulated in lung tumors, the influence of genetic variants on DNA methylation was investigated and in vitro studies were performed. We analyzed 394 CpG units within 19 CpG islands in the susceptibility regions in a screening set of 34 patients. Significant findings were validated in an independent patient set (n = 50) with available DNA and RNA. The most consistent overall DNA methylation difference between tumor and adjacent normal tissue on 15q25 was tumor hypomethylation in the promoter region of CHRNB4 with a median difference of 8% (P<0.001), which resulted in overexpression of the transcript in tumors (P<0.001). Confirming previous studies, we also found hypermethylation in CHRNA3 and telomerase reverse transcriptase (TERT) with significant expression changes. Decitabine treatment of H1299 cells resulted in reduced methylation levels in gene promoters, elevated transcript levels of CHRNB4 and CHRNA3, and a slight downregulation of TERT demonstrating epigenetic regulation of lung cancer cells. Single-nucleotide polymorphisms rs421629 on 5p15.33 and rs1948, rs660652, rs8040868 and rs2036527 on 15q25.1, previously identified as lung cancer risk or nicotine-addiction modifiers, were associated with tumor DNA methylation levels in the promoters of TERT and CHRNB4 (P<0.001), respectively, in two independent sample sets (n = 82;n = 150). In addition, CHRNB4 knockdown in two different cell lines (A549 and H1299) resulted in reduced proliferation ([P.sub.A549] <0.05;[P.sub.H1299] < 0.001) and propensity to form colonies in H1299 cells. These results suggest epigenetic deregulation of nicotinic acetylcholine receptor subunit (nAChR) genes which in the case of CHRNB4 is strongly associated with genetic lung cancer susceptibility variants and a functional impact on tumorigenic potential.
Molecular profiles of non-small cell lung cancers in cigarette smoking and never-smoking patients
Purpose: Molecular features of non-small cell lung cancer (NSCLC) in never-smokers are not well recognized. We assessed the expression of genes potentially related to lung cancer etiology in smoking vs. never-smoking NSCLC patients. Methods: We assayed frozen tumor samples from surgically resected 31 never-smoking and 54 clinically pair-matched smoking NSCLC patients, and from corresponding normal lung tissue from 27 and 43 patients, respectively. Expression of 21 genes, including cell membrane kinases, sex hormone receptors, transcription factors, growth factors and others was assessed by reverse transcription - quantitative PCR. Results: Expression of 5 genes was significantly higher in tumors of non-smokers vs. smokers: CSF1R (p<0.0001), RRAD (p<0.0001), PR (p=0.0004), TGFBR2 (p=0.0027) and EPHB6 (p=0.0033). Expression of AKR1B10 (p<0.0001), CDKN2A (p<0.0001), CHRNA6 (p<0.0001), SOX9 (p<0.0001), survivin (p<0.0001) and ER2 (p=0.002) was significantly higher in tumors compared to normal lung tissue. Expression of AR (p<0.0001), EPHB6 (p<0.0001), PR (p<0.0001), TGFBR2 (p<0.0001), TGFBR3 (p<0.0001), ER1 (p=0.0006) and DLG1 (p=0.0016) was significantly lower in tumors than in normal lung tissue. Expression of IGF2 was higher in tumors than in healthy lung tissue in never-smokers (p=0.003), and expression of AHR (p<0.0001), CSF1R (p<0.0001) and RRAD (p<0.0001) was lower in tumors than in healthy lung tissue in smokers. Conclusion: Expression of several genes in NSCLC is strongly related to smoking history. Lower expression of PR and higher expression of ER2 in tumors suggests a possibility of hormonal therapeutic intervention in selected NSCLC patients. Distinct molecular features of NSCLC in never-smokers, e.g. CHRNA6 upregulation, may prompt new treatment strategies.