Over the last years, the emergence of immune checkpoint inhibitors (ICI) has revolutionized the treatment of non-small cell lung cancer (NSCLC). Patients in a palliative setting with previously very poor prognosis may now show remarkable responses over years. Yet, ICI therapy is very cost-intensive and involves frequent contacts with healthcare resources.
View Article and Find Full Text PDFBackground: Recently, the combination of the programmed death-ligand 1 (PD-L1) inhibitor atezolizumab with first-line chemotherapy has demonstrated to improve outcome for patients with advanced small cell lung cancer (SCLC), leading to approval of this regimen. At the same time, accumulating (pre-)clinical data suggest synergisms of radiotherapy and immunotherapy via the radiation-mediated induction of anti-tumor immunogenicity. Combining the recent findings, the TREASURE trial aims at further enhancing response to upfront chemo-immunotherapy by the addition of thoracic radiotherapy (TRT).
View Article and Find Full Text PDFThe current risk stratification in prostate cancer (PCa) is frequently insufficient to adequately predict disease development and outcome. One hallmark of cancer is telomere maintenance. For telomere maintenance, PCa cells exclusively employ telomerase, making it essential for this cancer entity.
View Article and Find Full Text PDFBackground: Availability of potent anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKI) has pushed the median survival of ALK non-smallcell lung cancer (NSCLC) patients to over five years. In particular, second-generation ALK TKI have demonstrated superiority compared to the first-generation compound crizotinib and are meanwhile standard first-line treatment. However, clinical courses of individual patients vary widely, with secondary development of drug resistance and intracranial progression remaining important problems.
View Article and Find Full Text PDFBackground: Metastatic epidermal growth factor receptor-mutated (EGFR) non-small-cell lung cancer (NSCLC) can present or following previous nonmetastatic disease (secondary). Potential differences between these two patient subsets are unclear at present.
Methods: We retrospectively analyzed characteristics of tyrosine kinase inhibitor (TKI)-treated patients with vs.
Background: In selected patients with early-stage malignant pleural mesothelioma (MPM), a multimodal therapy that includes surgical cytoreduction, chemotherapy, and/or radiotherapy is recommended. Several clinical trials have demonstrated the beneficial effects of immune checkpoint inhibitors in pretreated MPM patients with advanced disease. Recent clinical data have suggested that the combination of chemotherapy and checkpoint inhibition might improve efficacy.
View Article and Find Full Text PDFBackground: Non-small cell lung cancer is the most common cause of cancer death worldwide, highlighting the need for novel therapeutic concepts. In particular, there is still a lack of treatment strategies for the group of elderly and frail patients, who are frequently not capable of receiving standard therapy regimens. Despite comprising the majority of lung cancer patients, this group is underrepresented in clinical trials.
View Article and Find Full Text PDFBackground: Etoposide-/platinum-based chemotherapy is the standard first-line treatment for extensive-disease small cell lung cancer (SCLC), but responses are short-lived and subsequent options limited. Here, we present our experience with paclitaxel in advanced treatment lines.
Methods: We retrospectively studied the clinical course of all paclitaxel-treated SCLC patients between 2005 and 2015 in our institution.
Background: The ends of linear chromosomes, the telomeres, comprise repetitive DNA sequences in complex with proteins that protects them from being processed by the DNA repair machinery. Cancer cells need to counteract the shortening of telomere repeats during replication for their unlimited proliferation by reactivating the reverse transcriptase telomerase or by using the alternative lengthening of telomeres (ALT) pathway. The different telomere maintenance (TM) mechanisms appear to involve hundreds of proteins but their telomere repeat length related activities are only partly understood.
View Article and Find Full Text PDFLeiomyosarcoma (LMS) is an aggressive mesenchymal malignancy with few therapeutic options. The mechanisms underlying LMS development, including clinically actionable genetic vulnerabilities, are largely unknown. Here we show, using whole-exome and transcriptome sequencing, that LMS tumors are characterized by substantial mutational heterogeneity, near-universal inactivation of TP53 and RB1, widespread DNA copy number alterations including chromothripsis, and frequent whole-genome duplication.
View Article and Find Full Text PDFThe microscopic analysis of telomere features provides a wealth of information on the mechanism by which tumor cells maintain their unlimited proliferative potential. Accordingly, the analysis of telomeres in tissue sections of patient tumor samples can be exploited to obtain diagnostic information and to define tumor subgroups. In many instances, however, analysis of the image data is conducted by manual inspection of 2D images at relatively low resolution for only a small part of the sample.
View Article and Find Full Text PDFTelomere maintenance is a hallmark of cancer as it provides cancer cells with cellular immortality. A significant fraction of tumors uses the alternative lengthening of telomeres (ALT) pathway to elongate their telomeres and to gain an unlimited proliferation potential. Since the ALT pathway is unique to cancer cells, it represents a potentially valuable, currently unexploited target for anti-cancer therapies.
View Article and Find Full Text PDFUpon genome damage, large-scale protein sumoylation occurs from yeast to humans to promote DNA repair. Currently, the underlying mechanism is largely unknown. Here we show that, upon DNA break induction, the budding yeast SUMO ligase Siz2 collaborates with the ssDNA-binding complex RPA (replication protein A) to induce the sumoylation of recombination factors and confer damage resistance.
View Article and Find Full Text PDFThe alternative lengthening of telomeres (ALT) mechanism allows cancer cells to escape senescence and apoptosis in the absence of active telomerase. A characteristic feature of this pathway is the assembly of ALT-associated promyelocytic leukemia (PML) nuclear bodies (APBs) at telomeres. Here, we dissected the role of APBs in a human ALT cell line by performing an RNA interference screen using an automated 3D fluorescence microscopy platform and advanced 3D image analysis.
View Article and Find Full Text PDFThe Ku70-Ku80 ring complex encloses DNA ends to facilitate telomere maintenance and DNA break repair. Many studies focus on the ring-forming regions of subunits Ku70 and Ku80. Less is known about the Ku70 C-terminal tail, which lies outside the ring.
View Article and Find Full Text PDFThe unlimited proliferation potential of cancer cells requires the maintenance of their telomeres. This is frequently accomplished by reactivation of telomerase. However, in a significant fraction of tumors an alternative lengthening of telomeres (ALT) mechanism is active.
View Article and Find Full Text PDFTelomerase-negative tumor cells use an alternative lengthening of telomeres (ALT) pathway that involves DNA recombination and repair to maintain their proliferative potential. The cytological hallmark of this process is the accumulation of promyelocytic leukemia (PML) nuclear protein at telomeric DNA to form ALT-associated PML bodies (APBs). Here, the de novo formation of a telomeric PML nuclear subcompartment was investigated by recruiting APB protein components.
View Article and Find Full Text PDFPromyelocytic leukemia nuclear bodies (PML-NBs) are mobile subnuclear organelles formed by PML and Sp100 protein. They have been reported to have a role in transcription, DNA replication and repair, telomere lengthening, cell cycle control and tumor suppression. We have conducted high-resolution 4Pi fluorescence laser-scanning microscopy studies complemented with correlative electron microscopy and investigations of the accessibility of the PML-NB subcompartment.
View Article and Find Full Text PDFTelomerase-negative tumor cells maintain their telomeres via an alternative lengthening of telomeres (ALT) mechanism. This process involves the association of telomeres with promyelocytic leukemia nuclear bodies (PML-NBs). Here, the mobility of both telomeres and PML-NBs as well as their interactions were studied in human U2OS osteosarcoma cells, in which the ALT pathway is active.
View Article and Find Full Text PDFEvolutionary conserved mitochondrial nucleases are involved in programmed cell death and normal cell proliferation in lower and higher eukaryotes. The endo/exonuclease Nuc1p, also termed 'yeast Endonuclease G (EndoG)', is a member of this class of enzymes that differs from mammalian homologs by the presence of a 5'-3' exonuclease activity in addition to its broad spectrum endonuclease activity. However, this exonuclease activity is thought to be essential for a function of the yeast enzyme in DNA recombination and repair.
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