@article{DjuzenovaZimmermannKatzeretal.2015,
  author    = {Djuzenova, Cholpon S. and Zimmermann, Marcus and Katzer, Astrid and Fiedler, Vanessa and Distel, Luitpold V. and Gasser, Martin and Waaga-Gasser, Anna-Maria and Flentje, Michael and Polat, B{\"u}lent},
  title     = {A prospective study on histone γ-H2AX and 53BP1 foci expression in rectal carcinoma patients: correlation with radiation therapy-induced outcome},
  series = {BMC Cancer},
  volume    = {15},
  journal   = {BMC Cancer},
  number    = {856},
  doi       = {10.1186/s12885-015-1890-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125303},
  year      = {2015},
  abstract  = {Background The prognostic value of histone γ-H2AX and 53BP1 proteins to predict the radiotherapy (RT) outcome of patients with rectal carcinoma (RC) was evaluated in a prospective study. High expression of the constitutive histone γ-H2AX is indicative of defective DNA repair pathway and/or genomic instability, whereas 53BP1 (p53-binding protein 1) is a conserved checkpoint protein with properties of a DNA double-strand breaks sensor. Methods Using fluorescence microscopy, we assessed spontaneous and radiation-induced foci of γ-H2AX and 53BP1 in peripheral blood mononuclear cells derived from unselected RC patients (n = 53) undergoing neoadjuvant chemo- and RT. Cells from apparently healthy donors (n = 12) served as references. Results The γ-H2AX assay of in vitro irradiated lymphocytes revealed significantly higher degree of DNA damage in the group of unselected RC patients with respect to the background, initial (0.5 Gy, 30 min) and residual (0.5 Gy and 2 Gy, 24 h post-radiation) damage compared to the control group. Likewise, the numbers of 53BP1 foci analyzed in the samples from 46 RC patients were significantly higher than in controls except for the background DNA damage. However, both markers were not able to predict tumor stage, gastrointestinal toxicity or tumor regression after curative RT. Interestingly, the mean baseline and induced DNA damage was found to be lower in the group of RC patients with tumor stage IV (n = 7) as compared with the stage III (n = 35). The difference, however, did not reach statistical significance, apparently, because of the limited number of patients. Conclusions The study shows higher expression of γ-H2AX and 53BP1 foci in rectal cancer patients compared with healthy individuals. Yet the data in vitro were not predictive in regard to the radiotherapy outcome.},
  language  = {en}
}
@article{DjuzenovaElsnerKatzeretal.2013,
  author    = {Djuzenova, Cholpon S. and Elsner, Ines and Katzer, Astrid and Worschech, Eike and Distel, Luitpold V. and Flentje, Michael and Polat, B{\"u}lent},
  title     = {Radiosensitivity in breast cancer assessed by the histone γ-H2AX and 53BP1 foci},
  series = {Radiation Oncology},
  journal   = {Radiation Oncology},
  doi       = {10.1186/1748-717X-8-98},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96110},
  year      = {2013},
  abstract  = {Background High expression of constitutive histone γ-H2AX, a sensitive marker of DNA damage, might be indicative of defective DNA repair pathway or genomic instability. 53BP1 (p53-binding protein 1) is a conserved checkpoint protein with properties of a DNA double-strand breaks sensor. This study explores the relationship between the clinical radiosensitivity of tumor patients and the expression/induction of γ-H2AX and 53BP1 in vitro. Methods Using immunostaining, we assessed spontaneous and radiation-induced foci of γ-H2AX and 53 BP1 in peripheral blood mononuclear cells derived from unselected breast cancer (BC) patients (n=57) undergoing radiotherapy (RT). Cells from apparently healthy donors (n=12) served as references. Results Non-irradiated cells from controls and unselected BC patients exhibited similar baseline levels of DNA damage assessed by γ-H2AX and 53BP1 foci. At the same time, the γ-H2AX assay of in vitro irradiated cells revealed significant differences between the control group and the group of unselected BC patients with respect to the initial (0.5 Gy, 30 min) and residual (2 Gy, 24 h post-radiation) DNA damage. The numbers of 53BP1 foci analyzed in 35 BC patients were significantly higher than in controls only in case of residual DNA damage. A weak correlation was found between residual foci of both proteins tested. In addition, cells from cancer patients with an adverse acute skin reaction (grade 3) to RT showed significantly increased radiation-induced γ-H2AX foci and their protracted disappearance compared to the group of BC patients with normal skin reaction (grade 0-1). The mean number of γ-H2AX foci after 5 clinical fractions was significantly higher than that before RT, especially in clinically radiosensitive patients. Conclusions The γ-H2AX assay may have potential for screening individual radiosensitivity of breast cancer patients.},
  subject      = {DNS-Sch{\"a}digung},
  language  = {en}
}
@article{HechtErberHarreretal.2015,
  author    = {Hecht, Markus and Erber, Sonja and Harrer, Thomas and Klinker, Hartwig and Roth, Thomas and Parsch, Hans and Fiebig, Nora and Fietkau, Rainer and Distel, Luitpold V.},
  title     = {Efavirenz Has the Highest Anti-Proliferative Effect of Non-Nucleoside Reverse Transcriptase Inhibitors against Pancreatic Cancer Cells},
  series = {PLoS ONE},
  volume    = {10},
  journal   = {PLoS ONE},
  number    = {6},
  doi       = {10.1371/journal.pone.0130277},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151694},
  pages     = {e0130277},
  year      = {2015},
  abstract  = {Background Cancer prevention and therapy in HIV-1-infected patients will play an important role in future. The non-nucleoside reverse transcriptase inhibitors (NNRTI) Efavirenz and Nevirapine are cytotoxic against cancer cells in vitro. As other NNRTIs have not been studied so far, all clinically used NNRTIs were tested and the in vitro toxic concentrations were compared to drug levels in patients to predict possible anti-cancer effects in vivo. Methods Cytotoxicity was studied by Annexin-V-APC/7AAD staining and flow cytometry in the pancreatic cancer cell lines BxPC-3 and Panc-1 and confirmed by colony formation assays. The 50\% effective cytotoxic concentrations (EC50) were calculated and compared to the blood levels in our patients and published data. Results The in vitro EC50 of the different drugs in the BxPC-3 pancreatic cancer cells were: Efavirenz 31.5\(\mu\)mol/l (= 9944ng/ml), Nevirapine 239\(\mu\)mol/l (= 63786ng/ml), Etravirine 89.0\(\mu\)mol/l (= 38740ng/ml), Lersivirine 543\(\mu\)mol/l (= 168523ng/ml), Delavirdine 171\(\mu\)mol/l (= 78072ng/ml), Rilpivirine 24.4\(\mu\)mol/l (= 8941ng/ml). As Efavirenz and Rilpivirine had the highest cytotoxic potential and Nevirapine is frequently used in HIV-1 positive patients, the results of these three drugs were further studied in Panc-1 pancreatic cancer cells and confirmed with colony formation assays. 205 patient blood levels of Efavirenz, 127 of Rilpivirine and 31 of Nevirapine were analyzed. The mean blood level of Efavirenz was 3587ng/ml (range 162-15363ng/ml), of Rilpivirine 144ng/ml (range 0-572ng/ml) and of Nevirapine 4955ng/ml (range 1856-8697ng/ml). Blood levels from our patients and from published data had comparable Efavirenz levels to the in vitro toxic EC50 in about 1 to 5\% of all patients. Conclusion All studied NNRTIs were toxic against cancer cells. A low percentage of patients taking Efavirenz reached in vitro cytotoxic blood levels. It can be speculated that in HIV-1 positive patients having high Efavirenz blood levels pancreatic cancer incidence might be reduced. Efavirenz might be a new option in the treatment of cancer.},
  language  = {en}
}
@article{KroeberWengerSchwegleretal.2015,
  author    = {Kroeber, Jana and Wenger, Barbara and Schwegler, Manuela and Daniel, Christoph and Schmidt, Manfred and Djuzenova, Cholpon S and Polat, B{\"u}lent and Flentje, Michael and Fietkau, Rainer and Distel, Luitpold V.},
  title     = {Distinct increased outliers among 136 rectal cancer patients assessed by \(\gamma\)H2AX},
  series = {Radiation Oncology},
  volume    = {10},
  journal   = {Radiation Oncology},
  number    = {36},
  doi       = {10.1186/s13014-015-0344-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144085},
  year      = {2015},
  abstract  = {Background: In recent years attention has focused on \(\gamma\)H2AX as a very sensitive double strand break indicator. It has been suggested that \(\gamma\)H2AX might be able to predict individual radiosensitivity. Our aim was to study the induction and repair of DNA double strand breaks labelled by \(\gamma\)H2AX in a large cohort. Methods: In a prospective study lymphocytes of 136 rectal cancer (RC) patients and 59 healthy individuals were ex vivo irradiated (IR) and initial DNA damage was compared to remaining DNA damage after 2 Gy and 24 hours repair time and preexisting DNA damage in unirradiated lymphocytes. Lymphocytes were immunostained with anti-\(\gamma\)H2AX antibodies and microscopic images with an extended depth of field were acquired. \(\gamma\)H2AX foci counting was performed using a semi-automatic image analysis software. Results: Distinct increased values of preexisting and remaining \(\gamma\)H2AX foci in the group of RC patients were found compared to the healthy individuals. Additionally there are clear differences within the groups and there are outliers in about 12\% of the RC patients after ex vivo IR. Conclusions: The \(\gamma\)H2AX assay has the capability to identify a group of outliers which are most probably patients with increased radiosensitivity having the highest risk of suffering radiotherapy-related late sequelae.},
  language  = {en}
}
@article{BohnertSeiffertTrellaetal.2020,
  author    = {Bohnert, Simone and Seiffert, Anja and Trella, Stefanie and Bohnert, Michael and Distel, Luitpold and Ondruschka, Benjamin and Monoranu, Camelia-Marie},
  title     = {TMEM119 as a specific marker of microglia reaction in traumatic brain injury in postmortem examination},
  series = {International Journal of Legal Medicine},
  volume    = {134},
  journal   = {International Journal of Legal Medicine},
  issn      = {0937-9827},
  doi       = {10.1007/s00414-020-02384-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235346},
  pages     = {2167-2176},
  year      = {2020},
  abstract  = {The aim of the present study was a refined analysis of neuroinflammation including TMEM119 as a useful microglia-specific marker in forensic assessments of traumatic causes of death, e.g., traumatic brain injury (TBI). Human brain tissue samples were obtained from autopsies and divided into cases with lethal TBI (n = 25) and subdivided into three groups according to their trauma survival time and compared with an age-, gender-, and postmortem interval-matched cohort of sudden cardiovascular fatalities as controls (n = 23). Brain tissue samples next to cortex contusions and surrounding white matter as well as samples of the ipsilateral uninjured brain stem and cerebellum were collected and stained immunohistochemically with antibodies against TMEM119, CD206, and CCR2. We could document the highest number of TMEM119-positive cells in acute TBI death with highly significant differences to the control numbers. CCR2-positive monocytes showed a significantly higher cell count in the cortex samples of TBI cases than in the controls with an increasing number of immunopositive cells over time. The number of CD206-positive M2 microglial cells increased survival time-dependent. After 3 days of survival, the cell number increased significantly in all four regions investigated compared with controls. In sum, we validate a specific and robustly expressed as well as fast reacting microglia marker, TMEM119, which distinguishes microglia from resident and infiltrating macrophages and thus offers a great potential for the estimation of the minimum survival time after TBI.},
  language  = {en}
}
@article{HechtMeierZimmeretal.2018,
  author    = {Hecht, Markus and Meier, Friedegund and Zimmer, Lisa and Polat, B{\"u}lent and Loquai, Carmen and Weishaupt, Carsten and Forschner, Andrea and Gutzmer, Ralf and Utikal, Jochen S. and Goldinger, Simone M. and Geier, Michael and Hassel, Jessica C. and Balermpas, Panagiotis and Kiecker, Felix and Rauschenberg, Ricarda and Dietrich, Ursula and Clemens, Patrick and Berking, Carola and Grabenbauer, Gerhard and Schadendorf, Dirk and Grabbe, Stephan and Schuler, Gerold and Fietkau, Rainer and Distel, Luitpold V. and Heinzerling, Lucie},
  title     = {Clinical outcome of concomitant vs interrupted BRAF inhibitor therapy during radiotherapy in melanoma patients},
  series = {British Journal of Cancer},
  volume    = {118},
  journal   = {British Journal of Cancer},
  doi       = {10.1038/bjc.2017.489},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227970},
  pages     = {785-792},
  year      = {2018},
  abstract  = {Background: Concomitant radiation with BRAF inhibitor (BRAFi) therapy may increase radiation-induced side effects but also potentially improve tumour control in melanoma patients. Methods: A total of 155 patients with BRAF-mutated melanoma from 17 European skin cancer centres were retrospectively analysed. Out of these, 87 patients received concomitant radiotherapy and BRAFi (59 vemurafenib, 28 dabrafenib), while in 68 patients BRAFi therapy was interrupted during radiation (51 vemurafenib, 17 dabrafenib). Overall survival was calculated from the first radiation (OSRT) and from start of BRAFi therapy (OSBRAFi). Results: The median duration of BRAFi treatment interruption prior to radiotherapy was 4 days and lasted for 17 days. Median OSRT and OSBRAFi in the entire cohort were 9.8 and 12.6 months in the interrupted group and 7.3 and 11.5 months in the concomitant group (P=0.075/P=0.217), respectively. Interrupted vemurafenib treatment with a median OSRT and OSBRAFi of 10.1 and 13.1 months, respectively, was superior to concomitant vemurafenib treatment with a median OSRT and OSBRAFi of 6.6 and 10.9 months (P=0.004/P=0.067). Interrupted dabrafenib treatment with a median OSRT and OSBRAFi of 7.7 and 9.8 months, respectively, did not differ from concomitant dabrafenib treatment with a median OSRT and OSBRAFi of 9.9 and 11.6 months (P=0.132/P=0.404). Median local control of the irradiated area did not differ in the interrupted and concomitant BRAFi treatment groups (P=0.619). Skin toxicity of grade ≥2 (CTCAE) was significantly increased in patients with concomitant vemurafenib compared to the group with treatment interruption (P=0.002). Conclusions: Interruption of vemurafenib treatment during radiation was associated with better survival and less toxicity compared to concomitant treatment. Due to lower number of patients, the relevance of treatment interruption in dabrafenib treated patients should be further investigated. The results of this analysis indicate that treatment with the BRAFi vemurafenib should be interrupted during radiotherapy. Prospective studies are desperately needed.},
  language  = {en}
}