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Bromodomains (BRDs) are conserved protein interaction modules which recognize (read) acetyl-lysine modifications, however their role(s) in regulating cellular states and their potential as targets for the development of targeted treatment strategies is poorly understood. Here we present a set of 25 chemical probes, selective small molecule inhibitors, covering 29 human bromodomain targets. We comprehensively evaluate the selectivity of this probe-set using BROMOscan and demonstrate the utility of the set identifying roles of BRDs in cellular processes and potential translational applications. For instance, we discovered crosstalk between histone acetylation and the glycolytic pathway resulting in a vulnerability of breast cancer cell lines under conditions of glucose deprivation or GLUT1 inhibition to inhibition of BRPF2/3 BRDs. This chemical probe-set will serve as a resource for future applications in the discovery of new physiological roles of bromodomain proteins in normal and disease states, and as a toolset for bromodomain target validation.
Ferroptosis is an iron-dependent form of cell death, which is triggered by disturbed membrane integrity due to an overproduction of lipid peroxides. Induction of ferroptosis comprises several alterations, i.e. altered iron metabolism, response to oxidative stress, or lipid peroxide production. At the physiological level transcription, translation, and microRNAs add to the appearance and/or activity of building blocks that negatively or positively balance ferroptosis. Ferroptosis contributes to tissue damage in the case of, e.g., brain and heart injury but may be desirable to overcome chemotherapy resistance. For a more complete picture, it is crucial to also consider the cellular microenvironment, which during inflammation and in the tumor context is dominated by hypoxia. This graphical review visualizes basic mechanisms of ferroptosis, categorizes general inducers and inhibitors of ferroptosis, and puts a focus on microRNAs, iron homeostasis, and hypoxia as regulatory components.
The integrated stress response (ISR) is a central cellular adaptive program that is activated by diverse stressors including ER stress, hypoxia and nutrient deprivation to orchestrate responses via activating transcription factor 4 (ATF4). We hypothesized that ATF4 is essential for the adaptation of human glioblastoma (GB) cells to the conditions of the tumor microenvironment and is contributing to therapy resistance against chemotherapy. ATF4 induction in GB cells was modulated pharmacologically and genetically and investigated in the context of temozolomide treatment as well as glucose and oxygen deprivation. The relevance of the ISR was analyzed by cell death and metabolic measurements under conditions to approximate aspects of the GB microenvironment. ATF4 protein levels were induced by temozolomide treatment. In line, ATF4 gene suppressed GB cells (ATF4sh) displayed increased cell death and decreased survival after temozolomide treatment. Similar results were observed after treatment with the ISR inhibitor ISRIB. ATF4sh and ISRIB treated GB cells were sensitized to hypoxia-induced cell death. Our experimental study provides evidence for an important role of ATF4 for the adaptation of human GB cells to conditions of the tumor microenvironment characterized by low oxygen and nutrient availability and for the development of temozolomide resistance. Inhibiting the ISR in GB cells could therefore be a promising therapeutic approach.
The DNA damage response (DDR) is a vast network of molecules that preserves genome integrity and allow the faithful transmission of genetic information in human cells. While the usual response to the detection of DNA lesions in cells involves the control of cell-cycle checkpoints, repair proteins or apoptosis, alterations of the repair processes can lead to cellular dysfunction, diseases, or cancer. Besides, cancer patients with DDR alterations often show poor survival and chemoresistance. Despite the progress made in recent years in identifying genes and proteins involved in DDR and their roles in cellular physiology and pathology, the question of the involvement of DDR in metabolism remains unclear. It remains to study the metabolites associated with specific repair pathways or alterations and to investigate whether differences exist depending on cellular origin. The identification of DDR-related metabolic pathways and of the pathways that cause metabolic reprogramming in DDR-deficient cells may produce new targets for the development of new therapies.
In this thesis, nuclear magnetic resonance spectroscopy (NMR) was used to assess the metabolic consequence of the loss of two central DNA repair proteins with importance in diseases context, ATM and RNase H2, in haematological cells. An increase in intracellular taurine was found in RNase H2- and ATM-deficient cells compared to wild-type cells for these genes and in cells after exposition to a source of DNA damage. The rise in taurine does not appear to result from an increase in its biosynthesis from cysteine, but more likely from other cellular processes such as degradation pathways.
Overall, evidence for metabolic reprogramming in haematological cells with faults in DNA repair resulting from ATM or RNase H2 deficiencies or upon exposition to a source of DNA damage is presented in this study.
To explore and describe attitudes and opinions towards suicidality in healthcare professionals (HCPs) working with oncological patients. Methods: A 48-item online questionnaire was developed and distributed to HCPs working with cancer patients. Three hundred fifty-four answered questionnaires were analyzed. Results: The majority of HCPs reported that they were able to understand why a cancer patient would commit suicide (87.8%) or would seek help from an assisted suicide organization (ASO; 83.9%). The understandable reasons were pain and physical impairments (51.4%), social isolation (19.8%), loss of control and autonomy (18.1%), terminal disease (17.2%), loss of meaning (15.3%), desperation (14.7%), and psychic distress (9.3%). Personal experiences with suicidality lead only 44.8% of HCPs to believe that thereby they would be better able to understand a patients’ wish for suicide. Religion was negatively associated with understanding of suicide and why a cancer patient would seek help from an ASO. Knowledge of suicidality was positively associated with why a cancer patient would seek help from an ASO. Conclusions: There is still little knowledge in oncology about the relation of HCPs’ attitudes toward suicidality in their patients and how those attitudes influence their behavior, especially care and treatment of patients. More research on this topic is needed. It stands to reason that more education about suicidality in cancer patients seems likely to improve understanding and attitudes and thereby influence care for cancer patients.
Background: Evaluation of automated attenuation-based tube potential selection and its impact on image quality and radiation dose in CT (computed tomography) examinations for cancer staging.
Methods: A total of 110 (59 men, 51 women) patients underwent chest-abdomen-pelvis CT examinations; 55 using a fixed tube potential of 120 kV/current of 210 Reference mAs (using CareDose4D), and 55 using automated attenuation-based tube potential selection (CAREkV) also using a current of 210 Reference mAs. This evaluation was performed as a single-centre, observer-blinded retrospective analysis. Image quality was assessed by two readers in consensus. Attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured or calculated for objective image evaluation. For the evaluation of radiation exposure, dose-length-product (DLP) values were compared and Size-specific dose estimates (SSDE) values were calculated.
Results: Diagnostic image quality was obtained from all patients. The median DLP (703.5 mGy · cm, range 390–2203 mGy · cm) was 7.9% lower when using the algorithm compared with the standard 120 kV protocol (median 756 mGy · cm, range 345–2267 mGy · cm). A reduction in potential to 100 kV occurred in 32 cases; therefore, these patients received significantly lower radiation exposure compared with the 120 kV protocol.
Conclusion: Automated attenuation-based tube potential selection produces good diagnostic image quality in chest-abdomen-pelvis CT and reduces the patient’s overall radiation dose by 7.9% compared to the standard 120 kV protocol.
Clinical outcomes of cancer-associated isolated superficial vein thrombosis in daily practice
(2022)
Highlights
• In acute isolated SVT, the prevalence of cancer is almost 7 %.
• Cancer increases the SVT-associated VTE risk at 3 and 12 months.
• Cancer patients with isolated SVT may benefit from prolonged anticoagulation.
Abstract
Background: Despite significant progress in the understanding of paraneoplastic deep vein thrombosis (DVT) and pulmonary embolism (PE), little is known about the outcomes of cancer-associated superficial vein thrombosis (SVT) in daily practice.
Methods: INSIGHTS-SVT was a prospective observational study on patients with acute isolated SVT. Primary outcome measure was symptomatic venous thromboembolism (VTE), a composite of DVT, PE, and SVT extension/recurrence, at 3 months. Clinically relevant bleeding was also assessed.
Results: Of 1151 patients included, 6.7 % either had active cancer at baseline or were diagnosed with cancer during 12 months of follow-up. At 3 months, symptomatic VTE had occurred in 13.0 % and 5.4 % of cancer and non-cancer patients, respectively (HR 2.6, 95 % CI 1.3–5.0). Regarding secondary outcomes, cancer patients had increased risks of DVT and PE (HR 3.9, 95 % CI 1.3–11.8) and hospitalization due to VTE (HR 11.0, 95 % CI 2.5–49.0). The rate of clinically relevant bleeding was numerically higher in the cancer cohort (3.9 % vs 1.3 %, HR 3.1, 95 % CI 0.9–10.7). At 12 months, the primary composite outcome had occurred in 15.6 % and 11.9 % of cancer and non-cancer patients, respectively (HR 1.9, 95 % CI 1.0–3.5). After adjusting for additional risk factors, including age, history of DVT/PE and cardiovascular risk factors/diseases, the association of cancer with the primary outcome remained statistically significant.
Conclusion: Cancer patients with isolated SVT are at significant risk of symptomatic VTE. While most events occur within 3 months, the VTE risk remains elevated up to one year of follow-up.
ClinicalTrials.gov identifier: NCT02699151.
Chimeric antigen receptor (CAR)-T cell therapies are on the verge of becoming powerful immunotherapeutic tools for combating hematological diseases confronted with pressing medical needs. Lately, CAR-NK cell therapies have also come into focus as novel therapeutic options to address hurdles related to CAR-T cell therapies, such as therapy-induced side effects. Currently, more than 500 CAR-T and 17 CAR-NK cell trials are being conducted worldwide including the four CAR-T cell products Kymriah, Yescarta, Tecartus and Breyanzi, which are already available on the market. Most CAR-T cell-based gene therapy products that are under clinical evaluation consist of autologous enriched T cells, whereas CAR-NK cell-based approaches can be generated from allogeneic donors. Besides modification based on a second-generation CAR, more advanced CAR-immune cell therapeutics are being tested, which utilize precise insertion of genes to circumvent graft-versus-host disease (GvHD) or employ a dual targeting approach and adapter CARs in order to avoid therapy resistance caused by antigen loss. In this review, we are going to take a closer look at the commercial CAR-T cell therapies, as well as on CAR-T and CAR-NK cell products, which are currently under evaluation in clinical trials, that are being conducted in Germany.
Chordomas are rare bone tumors with few therapeutic options. Here we show, using whole-exome and genome sequencing within a precision oncology program, that advanced chordomas (n = 11) may be characterized by genomic patterns indicative of defective homologous recombination (HR) DNA repair and alterations affecting HR-related genes, including, for example, deletions and pathogenic germline variants of BRCA2, NBN, and CHEK2. A mutational signature associated with HR deficiency was significantly enriched in 72.7% of samples and co-occurred with genomic instability. The poly(ADP-ribose) polymerase (PARP) inhibitor olaparib, which is preferentially toxic to HR-incompetent cells, led to prolonged clinical benefit in a patient with refractory chordoma, and whole-genome analysis at progression revealed a PARP1 p.T910A mutation predicted to disrupt the autoinhibitory PARP1 helical domain. These findings uncover a therapeutic opportunity in chordoma that warrants further exploration, and provide insight into the mechanisms underlying PARP inhibitor resistance.
Objective: To analyze the financial burden of complementary and alternative medicine (CAM) in cancer treatment. Materials and Methods: Based on a systematic search of the literature (Medline and the Cochrane Library, combining the MeSH terms ‘complementary therapies', ‘neoplasms', ‘costs', ‘cost analysis', and ‘cost-benefit analysis'), an expert panel discussed different types of analyses and their significance for CAM in oncology. Results: Of 755 publications, 43 met our criteria. The types of economic analyses and their parameters discussed for CAM in oncology were cost, cost-benefit, cost-effectiveness, and cost-utility analyses. Only a few articles included arguments in favor of or against these different methods, and only a few arguments were specific for CAM because most CAM methods address a broad range of treatment aim parameters to assess effectiveness and are hard to define. Additionally, the choice of comparative treatments is difficult. To evaluate utility, healthy subjects may not be adequate as patients with a life-threatening disease and may be judged differently, especially with respect to a holistic treatment approach. We did not find any arguments in the literature that were directed at the economic analysis of CAM in oncology. Therefore, a comprehensive approach assessment based on criteria from evidence-based medicine evaluating direct and indirect costs is recommended. Conclusion: The usual approaches to conventional medicine to assess costs, benefits, and effectiveness seem adequate in the field of CAM in oncology. Additionally, a thorough deliberation on the comparator, endpoints, and instruments is mandatory for designing studies.