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1.
Eur J Cancer ; 207: 114144, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38852290

ABSTRACT

PURPOSE: Providing patient access to precision oncology (PO) is a major challenge of clinical oncologists. Here, we provide an easily transferable model from strategic management science to assess the outreach of a cancer center. METHODS: As members of the German WERA alliance, the cancer centers in Würzburg, Erlangen, Regensburg and Augsburg merged care data regarding their geographical impact. Specifically, we examined the provenance of patients from WERA´s molecular tumor boards (MTBs) between 2020 and 2022 (n = 2243). As second dimension, we added the provenance of patients receiving general cancer care by WERA. Clustering our catchment area along these two dimensions set up a four-quadrant matrix consisting of postal code areas with referrals towards WERA. These areas were re-identified on a map of the Federal State of Bavaria. RESULTS: The WERA matrix overlooked an active screening area of 821 postal code areas - representing about 50 % of Bavaria´s spatial expansion and more than six million inhabitants. The WERA matrix identified regions successfully connected to our outreach structures in terms of subsidiarity - with general cancer care mainly performed locally but PO performed in collaboration with WERA. We also detected postal code areas with a potential PO backlog - characterized by high levels of cancer care performed by WERA and low levels or no MTB representation. CONCLUSIONS: The WERA matrix provided a transparent portfolio of postal code areas, which helped assessing the geographical impact of our PO program. We believe that its intuitive principle can easily be transferred to other cancer centers.

2.
Am J Nucl Med Mol Imaging ; 13(5): 208-216, 2023.
Article in English | MEDLINE | ID: mdl-38023816

ABSTRACT

BACKGROUND: The aim of this study was to determine the read-out capabilities of the novel C-X-C motif chemokine receptor 4 (CXCR4)-targeting radiotracer [68Ga]Ga-PentixaFor compared to the reference radiotracer [18F]FDG in untreated individuals with head and neck squamous cell carcinoma (HNSCC). MATERIAL AND METHODS: 12 patients with histologically confirmed HNSCC were scheduled for [18F]FDG and [68Ga]Ga-PentixaFor PET/CT. Maximum standardized uptake values (SUVmax) and target-to-background ratios (TBR) were applied with vena cava superior serving as reference. In addition, we compared [68Ga]Ga-PentixaFor-PET findings with immunohistochemical (IHC) results of CXCR4 expression. RESULTS: On visual assessment, [18F]FDG identified more sites of disease, with increased detection rates for both the primary tumor ([18F]FDG, 12/12 [100%] vs. [68Ga]Ga-PentixaFor, 10/12 [83%]) and LN metastases ([18F]FDG, 9/12 [75%] vs. [68Ga]Ga-PentixaFor, 8/12 [67%]). Indicative for improved image contrast using [18F]FDG, quantification showed a higher TBR for the latter radiotracer, when compared to [68Ga]Ga-PentixaFor for all lesions ([18F]FDG, 11.7 ± 8.5 vs. [68Ga]Ga-PentixaFor, 4.3 ± 1.3; P=0.03), primary tumors ([18F]FDG, 13.6 ± 8.7 vs. [68Ga]Ga-PentixaFor, 4.4 ± 1.4; P<0.01), and LN lesions ([18F]FDG, 9.3 ± 10.6 vs. [68Ga]Ga-PentixaFor, 4.7 ± 1.5; P=0.3). IHC showed variable CXCR4 expression in the primary and LN, along with no associations between ex-vivo CXCR4 upregulation and [68Ga]Ga-PentixaFor-based TBR (R=0.33, P=0.39) or SUVmax (R=0.44, P=0.2). Of note, IHC also revealed heterogeneous expression of CXCR4 in immune cells in the tumor microenvironment and in germinal centers, indicative for inflammatory reactions. CONCLUSIONS: In HNSCC, [18F]FDG demonstrated superior diagnostic performance relative to [68Ga]Ga-PentixaFor, in particular for assessment of the primary. Based on the IHC analyses, these findings may be explained by CXCR4 upregulation not only by tumor but also by immune cells in the tumor microenvironment.

3.
Clin Nucl Med ; 48(11): 923-927, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37756444

ABSTRACT

BACKGROUND: Given their neuroendocrine origin, head and neck paragangliomas (HNPGLs) can be imaged with somatostatin receptor (SSTR)-directed PET/CT. We aimed to determine whether the in vivo PET signal can differentiate between varying HNPGL subtypes. PATIENTS AND METHODS: Fourteen patients with HNPGL received pretherapeutic SSTR-PET/CTs using 68 Ga-DOTATOC. Six (42.9%) patients had a jugular paraganglioma (PGL-J), 5 (35.7%) were diagnosed with carotid paraganglioma (PGL-Cs), and the remaining 3 patients (21.4%) had PGL-C with pathogenic SDHx germline variants (PGL-C-SDH). A visual and quantitative assessment of the primary tumor on SSTR-PET was performed, including SUV max and target-to-background ratio (TBR). Quantitative values were then compared between subgroups of patients affected with different HNPGL entities. RESULTS: On visual assessment, all primary HNPGLs could be identified on SSTR-PET/CT. Quantification of HNPGL revealed substantially elevated SUV max in PGL-J (101.7 ± 58.5) when compared with PGL-C-SDH (13.4 ± 5.6, P < 0.05), but not when compared with PGL-C (66.7 ± 27.3, P = 0.4; PGL-C vs PGL-C-SDH, P = 0.2). TBR of PGL-J (202.9 ± 82.2), however, further differentiated between PGL-C (95.7 ± 45.4, P < 0.05) and PGL-C-SDH (20.4 ± 12.2, P < 0.01; PGL-C vs PGL-C-SDH, P = 0.3). Moreover, whole-body readout revealed metastases in 2/3 (66.7%) of PGL-C-SDH patients, with a single SSTR-expressing skeletal lesion in one subject and bipulmonary lesions in the other patient. CONCLUSIONS: In patients with HNPGL, SSTR-PET/CT identified the primary and metastatic disease and provides substantially elevated TBR, indicating excellent image contrast. PET-based quantification can also differentiate between varying HNPGL subtypes.


Subject(s)
Head and Neck Neoplasms , Paraganglioma, Extra-Adrenal , Paraganglioma , Humans , Positron Emission Tomography Computed Tomography/methods , Receptors, Somatostatin , Head and Neck Neoplasms/diagnostic imaging , Paraganglioma, Extra-Adrenal/pathology , Paraganglioma/diagnostic imaging
4.
Front Oncol ; 13: 1231601, 2023.
Article in English | MEDLINE | ID: mdl-37664054

ABSTRACT

Diagnosing any of the more than 30 types of T-cell lymphomas is considered a challenging task for many pathologists and currently requires morphological expertise as well as the integration of clinical data, immunophenotype, flow cytometry and clonality analyses. Even considering all available information, some margin of doubt might remain using the current diagnostic procedures. In recent times, the genetic landscape of most T-cell lymphomas has been elucidated, showing a number of diagnostically relevant mutations. In addition, recent data indicate that some of these genetic alterations might bear prognostic and predictive value. Extensive genetic analyses, such as whole exome or large panel sequencing are still expensive and time consuming, therefore limiting their application in routine diagnostic. We therefore devoted our effort to develop a lean approach for genetic analysis of T-cell lymphomas, focusing on maximum efficiency rather than exhaustively covering all possible targets. Here we report the results generated with our small amplicon-based panel that could be used routinely on paraffin-embedded and even decalcified samples, on a single sample basis in parallel with other NGS-panels used in our routine diagnostic lab, in a relatively short time and with limited costs. We tested 128 available samples from two German reference centers as part of our routine work up (among which 116 T-cell lymphomas), which is the largest routine diagnostic series reported to date. Our results showed that this assay had a very high rate of technical success (97%) and could detect mutations in the majority (79%) of tested T-cell lymphoma samples.

5.
Pathol Res Pract ; 249: 154779, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37633005

ABSTRACT

Rhabdomyosarcoma (RMS) with EWSR1/FUS::TFCP2 fusion is an emerging, molecularly defined, rare subtype of RMS. It can affect patients in a wide age range and follows an aggressive clinical course according to the reported cases. Due to its unusual clinical and pathohistological features, with a typical intraosseous presentation and common cytokeratin expression, the diagnosis is challenging, and metastatic undifferentiated/sarcomatoid carcinoma can be an important differential diagnosis. We report here a case of a 55-year-old woman with an RMS with EWSR1::TFCP2 fusion mimicking metastatic lung cancer in view of the clinical and microscopic presentation. However, further molecular workup, including RNA sequencing, led to the proper diagnosis. Although these tumors are rare, knowledge of their unique features is essential for correct diagnosis as a basis for clinical management and optimization of therapeutic approaches.


Subject(s)
Carcinoma , Lung Neoplasms , Rhabdomyosarcoma, Embryonal , Rhabdomyosarcoma , Female , Humans , Adult , Child , Middle Aged , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Diagnosis, Differential , Transcription Factors/genetics , RNA-Binding Protein EWS/genetics , DNA-Binding Proteins
6.
Nat Commun ; 14(1): 3659, 2023 06 20.
Article in English | MEDLINE | ID: mdl-37339985

ABSTRACT

Iron is essential to cells as a cofactor in enzymes of respiration and replication, however without correct storage, iron leads to the formation of dangerous oxygen radicals. In yeast and plants, iron is transported into a membrane-bound vacuole by the vacuolar iron transporter (VIT). This transporter is conserved in the apicomplexan family of obligate intracellular parasites, including in Toxoplasma gondii. Here, we assess the role of VIT and iron storage in T. gondii. By deleting VIT, we find a slight growth defect in vitro, and iron hypersensitivity, confirming its essential role in parasite iron detoxification, which can be rescued by scavenging of oxygen radicals. We show VIT expression is regulated by iron at transcript and protein levels, and by altering VIT localization. In the absence of VIT, T. gondii responds by altering expression of iron metabolism genes and by increasing antioxidant protein catalase activity. We also show that iron detoxification has an important role both in parasite survival within macrophages and in virulence in a mouse model. Together, by demonstrating a critical role for VIT during iron detoxification in T. gondii, we reveal the importance of iron storage in the parasite and provide the first insight into the machinery involved.


Subject(s)
Parasites , Toxoplasma , Animals , Mice , Toxoplasma/metabolism , Vacuoles/metabolism , Reactive Oxygen Species/metabolism , Membrane Transport Proteins/metabolism , Parasites/metabolism , Protozoan Proteins/genetics , Protozoan Proteins/metabolism
8.
J Clin Med ; 12(2)2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36675498

ABSTRACT

Due to the wide variety of benign and malignant salivary gland tumors, classification and malignant behavior determination based on histomorphological criteria can be difficult and sometimes impossible. Spectroscopical procedures can acquire molecular biological information without destroying the tissue within the measurement processes. Since several tissue preparation procedures exist, our study investigated the impact of these preparations on the chemical composition of healthy and tumorous salivary gland tissue by Fourier-transform infrared (FTIR) microspectroscopy. Sequential tissue cross-sections were prepared from native, formalin-fixed and formalin-fixed paraffin-embedded (FFPE) tissue and analyzed. The FFPE cross-sections were dewaxed and remeasured. By using principal component analysis (PCA) combined with a discriminant analysis (DA), robust models for the distinction of sample preparations were built individually for each parotid tissue type. As a result, the PCA-DA model evaluation showed a high similarity between native and formalin-fixed tissues based on their chemical composition. Thus, formalin-fixed tissues are highly representative of the native samples and facilitate a transfer from scientific laboratory analysis into the clinical routine due to their robust nature. Furthermore, the dewaxing of the cross-sections entails the loss of molecular information. Our study successfully demonstrated how FTIR microspectroscopy can be used as a powerful tool within existing clinical workflows.

9.
Malar J ; 22(1): 5, 2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36604655

ABSTRACT

BACKGROUND: Polymorphisms in ATP2B4 coding for PMCA4b, the primary regulator of erythrocyte calcium concentration, have been shown by GWAS and cross-sectional studies to protect against severe malaria but the mechanism remains unknown. METHODS: Using a recall-by-genotype design, we investigated the impact of a common haplotype variant in ATP2B4 using in vitro assays that model erythrocyte stage malaria pathogenesis. Ninety-six donors representing homozygote (carriers of the minor allele, C/C), heterozygote (T/C) and wildtype (T/T) carriers of the tagging SNP rs1541252 were selected from a cohort of over 12,000 participants in the Keneba Biobank. RESULTS: Red blood cells (RBCs) from homozygotes showed reduced PMCA4b protein expression (mean fluorescence intensities (MFI = 2428 ± 124, 3544 ± 159 and 4261 ± 283], for homozygotes, heterozygotes and wildtypes respectively, p < 0.0001) and slower rates of calcium expulsion (calcium t½ ± SD = 4.7 ± 0.5, 1.8 ± 0.3 and 1.9 ± 0.4 min, p < 0.0001). Growth of a Plasmodium falciparum laboratory strain (FCR3) and two Gambian field isolates was decreased in RBCs from homozygotes compared to heterozygotes and wildtypes (p < 0.01). Genotype group did not affect parasite adhesion in vitro or var-gene expression in malaria-infected RBCs. Parasite growth was inhibited by a known inhibitor of PMCA4b, aurintricarboxylic acid (IC50 = 122uM CI: 110-134) confirming its sensitivity to calcium channel blockade. CONCLUSION: The data support the hypothesis that this ATP2B4 genotype, common in The Gambia and other malaria-endemic areas, protects against severe malaria through the suppression of parasitaemia during an infection. Reduction in parasite density plays a pivotal role in disease outcome by minimizing all aspects of malaria pathogenesis. Follow up studies are needed to further elucidate the mechanism of protection and to determine if this ATP2B4 genotype carries a fitness cost or increases susceptibility to other human disease.


Subject(s)
Malaria, Falciparum , Plasma Membrane Calcium-Transporting ATPases , Adult , Humans , Calcium/metabolism , Cross-Sectional Studies , Erythrocytes/parasitology , Gambia , Malaria, Falciparum/genetics , Plasma Membrane Calcium-Transporting ATPases/genetics , Plasma Membrane Calcium-Transporting ATPases/metabolism , Plasmodium falciparum , Polymorphism, Single Nucleotide
10.
J Cancer Res Clin Oncol ; 149(8): 5417-5428, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36451043

ABSTRACT

PURPOSE: Therapeutic options for breast cancer (BC) treatment are constantly evolving. The Human Epidermal Growth Factor 2 (HER2)-low BC entity is a new subgroup, representing about 55% of all BC patients. New antibody-drug conjugates demonstrated promising results for this BC subgroup. Currently, there is limited information about the conversion of HER2 subtypes between primary tumor and recurrent disease. METHODS: This retrospective study included women with BC at the University Medical Centre Wuerzburg from 1998 to 2021. Data were retrieved from patients' records. HER2 evolution from primary diagnosis to the first relapse and the development of secondary metastases was investigated. RESULTS: In the HR-positive subgroup without HER2 overexpression, HER2-low expression in primary BC was 56.7 vs. 14.6% in the triple-negative subgroup (p < 0.000). In the cohort of the first relapse, HER2-low represented 64.1% of HR-positive vs. 48.2% of the triple-negative cohort (p = 0.03). In patients with secondary metastases, HER2-low was 75.6% vs. 50% in the triple negative subgroup (p = 0.10). The subgroup of HER2-positive breast cancer patients numerically increased in the course of disease; the HER2-negative overall cohort decreased. A loss of HER2 expression from primary BC to the first relapse correlated with a better OS (p = 0.018). No clinicopathological or therapeutic features could be identified as potential risk factors for HER2 conversion. CONCLUSION: HER2 expression is rising during the progression of BC disease. In view of upcoming therapeutical options, the re-analysis of newly developed metastasis will become increasingly important.


Subject(s)
Breast Neoplasms , Neoplasms, Second Primary , Female , Humans , Breast Neoplasms/pathology , Prognosis , Retrospective Studies , Receptor, ErbB-2/metabolism , Neoplasms, Second Primary/complications , Recurrence , Melanoma, Cutaneous Malignant
11.
Diagnostics (Basel) ; 14(1)2023 Dec 30.
Article in English | MEDLINE | ID: mdl-38201401

ABSTRACT

Salivary gland tumors (SGTs) are a relevant, highly diverse subgroup of head and neck tumors whose entity determination can be difficult. Confocal Raman imaging in combination with multivariate data analysis may possibly support their correct classification. For the analysis of the translational potential of Raman imaging in SGT determination, a multi-stage evaluation process is necessary. By measuring a sample set of Warthin tumor, pleomorphic adenoma and non-tumor salivary gland tissue, Raman data were obtained and a thorough Raman band analysis was performed. This evaluation revealed highly overlapping Raman patterns with only minor spectral differences. Consequently, a principal component analysis (PCA) was calculated and further combined with a discriminant analysis (DA) to enable the best possible distinction. The PCA-DA model was characterized by accuracy, sensitivity, selectivity and precision values above 90% and validated by predicting model-unknown Raman spectra, of which 93% were classified correctly. Thus, we state our PCA-DA to be suitable for parotid tumor and non-salivary salivary gland tissue discrimination and prediction. For evaluation of the translational potential, further validation steps are necessary.

12.
Cell Death Discov ; 8(1): 505, 2022 Dec 31.
Article in English | MEDLINE | ID: mdl-36587029

ABSTRACT

Altered features of tumor cells acquired across therapy can result in the survival of treatment-resistant clones that may cause minimal residual disease (MRD). Despite the efficacy of ibrutinib in treating relapsed/refractory mantle cell lymphoma, the obstacle of residual cells contributes to relapses of this mature B-cell neoplasm, and the disease remains incurable. RNA-seq analysis of an ibrutinib-sensitive mantle cell lymphoma cell line following ibrutinib incubation of up to 4 d, corroborated our previously postulated resistance mechanism of a metabolic switch to reliance on oxidative phosphorylation (OXPHOS) in surviving cells. Besides, we had shown that treatment-persisting cells were characterized by increased CD52 expression. Therefore, we hypothesized that combining ibrutinib with another agent targeting these potential escape mechanisms could minimize the risk of survival of ibrutinib-resistant cells. Concomitant use of ibrutinib with OXPHOS-inhibitor IACS-010759 increased toxicity compared to ibrutinib alone. Targeting CD52 was even more efficient, as addition of CD52 mAb in combination with human serum following ibrutinib pretreatment led to rapid complement-dependent-cytotoxicity in an ibrutinib-sensitive cell line. In primary mantle cell lymphoma cells, a higher toxic effect with CD52 mAb was obtained, when cells were pretreated with ibrutinib, but only in an ibrutinib-sensitive cohort. Given the challenge of treating multi-resistant mantle cell lymphoma patients, this work highlights the potential use of anti-CD52 therapy as consolidation after ibrutinib treatment in patients who responded to the BTK inhibitor to achieve MRD negativity and prolong progression-free survival.

13.
Virchows Arch ; 481(6): 935-943, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36219238

ABSTRACT

The subclassification of diffuse large B-cell lymphoma (DLBCL) into germinal center B-cell-like (GCB) and activated B-cell-like (ABC) subtypes has become mandatory in the 2017 update of the WHO classification of lymphoid neoplasms and will continue to be used in the WHO 5th edition. The RNA-based Lymph2Cx assay has been validated as a reliable surrogate of high-throughput gene expression profiling assays for distinguishing between GCB and ABC DLBCL and provides reliable results from formalin-fixed, paraffin-embedded (FFPE) material. This test has been previously used in clinical trials, but experience from real-world routine application is rare. We routinely applied the Lymph2Cx assay to day-to-day diagnostics on a series of 147 aggressive B-cell lymphoma cases and correlated our results with the immunohistochemical subclassification using the Hans algorithm and fluorescence in situ hybridization findings using break-apart probes for MYC, BCL2, and BCL6. The routine use of the Lymph2Cx assay had a high technical success rate (94.6%) with a low rate of failure due to poor material and/or RNA quality. The Lymph2Cx assay was discordant with the Hans algorithm in 18% (23 of 128 cases). Discordant cases were mainly classified as GCB by the Hans algorithm and as ABC by Lymph2Cx (n = 11, 8.6%). Only 5 cases (3.9%) were classified as non-GCB by the Hans algorithm and as GCB by Lymph2Cx. Additionally, 5.5% of cases (n = 7) were left unclassified by Lymph2Cx, whereas they were defined as GCB (n = 4) or non-GCB (n = 3) by the Hans algorithm. Our data support the routine applicability of the Lymph2Cx assay.


Subject(s)
Lymphoma, Large B-Cell, Diffuse , Humans , In Situ Hybridization, Fluorescence , Prospective Studies , Lymphoma, Large B-Cell, Diffuse/diagnosis , Lymphoma, Large B-Cell, Diffuse/genetics , Germinal Center/pathology , RNA/metabolism , RNA/therapeutic use
14.
Nat Commun ; 13(1): 6220, 2022 10 20.
Article in English | MEDLINE | ID: mdl-36266281

ABSTRACT

Hotspot mutations in the PEST-domain of NOTCH1 and NOTCH2 are recurrently identified in B cell malignancies. To address how NOTCH-mutations contribute to a dismal prognosis, we have generated isogenic primary human tumor cells from patients with Chronic Lymphocytic Leukemia (CLL) and Mantle Cell Lymphoma (MCL), differing only in their expression of the intracellular domain (ICD) of NOTCH1 or NOTCH2. Our data demonstrate that both NOTCH-paralogs facilitate immune-escape of malignant B cells by up-regulating PD-L1, partly dependent on autocrine interferon-γ signaling. In addition, NOTCH-activation causes silencing of the entire HLA-class II locus via epigenetic regulation of the transcriptional co-activator CIITA. Notably, while NOTCH1 and NOTCH2 govern similar transcriptional programs, disease-specific differences in their expression levels can favor paralog-specific selection. Importantly, NOTCH-ICD also strongly down-regulates the expression of CD19, possibly limiting the effectiveness of immune-therapies. These NOTCH-mediated immune escape mechanisms are associated with the expansion of exhausted CD8+ T cells in vivo.


Subject(s)
Lymphoma , Receptor, Notch1 , Humans , Receptor, Notch1/metabolism , B7-H1 Antigen/metabolism , Interferon-gamma/metabolism , CD8-Positive T-Lymphocytes/metabolism , Epigenesis, Genetic , Signal Transduction , Receptor, Notch2/genetics , Receptor, Notch2/metabolism , Lymphoma/genetics
15.
Cancers (Basel) ; 14(20)2022 Oct 14.
Article in English | MEDLINE | ID: mdl-36291825

ABSTRACT

(1) Background: molecular tumor boards (MTBs) are crucial instruments for discussing and allocating targeted therapies to suitable cancer patients based on genetic findings. Currently, limited evidence is available regarding the regional impact and the outreach component of MTBs; (2) Methods: we analyzed MTB patient data from four neighboring Bavarian tertiary care oncology centers in Würzburg, Erlangen, Regensburg, and Augsburg, together constituting the WERA Alliance. Absolute patient numbers and regional distribution across the WERA-wide catchment area were weighted with local population densities; (3) Results: the highest MTB patient numbers were found close to the four cancer centers. However, peaks in absolute patient numbers were also detected in more distant and rural areas. Moreover, weighting absolute numbers with local population density allowed for identifying so-called white spots-regions within our catchment that were relatively underrepresented in WERA MTBs; (4) Conclusions: investigating patient data from four neighboring cancer centers, we comprehensively assessed the regional impact of our MTBs. The results confirmed the success of existing collaborative structures with our regional partners. Additionally, our results help identifying potential white spots in providing precision oncology and help establishing a joint WERA-wide outreach strategy.

16.
Cell Biosci ; 12(1): 50, 2022 Apr 27.
Article in English | MEDLINE | ID: mdl-35477555

ABSTRACT

BACKGROUND: Despite advances in treatment of patients with non-small cell lung cancer, carriers of certain genetic alterations are prone to failure. One such factor frequently mutated, is the tumor suppressor PTEN. These tumors are supposed to be more resistant to radiation, chemo- and immunotherapy. RESULTS: We demonstrate that loss of PTEN led to altered expression of transcriptional programs which directly regulate therapy resistance, resulting in establishment of radiation resistance. While PTEN-deficient tumor cells were not dependent on DNA-PK for IR resistance nor activated ATR during IR, they showed a significant dependence for the DNA damage kinase ATM. Pharmacologic inhibition of ATM, via KU-60019 and AZD1390 at non-toxic doses, restored and even synergized with IR in PTEN-deficient human and murine NSCLC cells as well in a multicellular organotypic ex vivo tumor model. CONCLUSION: PTEN tumors are addicted to ATM to detect and repair radiation induced DNA damage. This creates an exploitable bottleneck. At least in cellulo and ex vivo we show that low concentration of ATM inhibitor is able to synergise with IR to treat PTEN-deficient tumors in genetically well-defined IR resistant lung cancer models.

17.
Front Cell Dev Biol ; 10: 785252, 2022.
Article in English | MEDLINE | ID: mdl-35372352

ABSTRACT

Macroautophagy (hereafter referred to as autophagy) is a homeostatic process that preserves cellular integrity. In mice, autophagy regulates pancreatic ductal adenocarcinoma (PDAC) development in a manner dependent on the status of the tumor suppressor gene Trp53. Studies published so far have investigated the impact of autophagy blockage in tumors arising from Trp53-hemizygous or -homozygous tissue. In contrast, in human PDACs the tumor suppressor gene TP53 is mutated rather than allelically lost, and TP53 mutants retain pathobiological functions that differ from complete allelic loss. In order to better represent the patient situation, we have investigated PDAC development in a well-characterized genetically engineered mouse model (GEMM) of PDAC with mutant Trp53 (Trp53 R172H ) and deletion of the essential autophagy gene Atg7. Autophagy blockage reduced PDAC incidence but had no impact on survival time in the subset of animals that formed a tumor. In the absence of Atg7, non-tumor-bearing mice reached a similar age as animals with malignant disease. However, the architecture of autophagy-deficient, tumor-free pancreata was effaced, normal acinar tissue was largely replaced with low-grade pancreatic intraepithelial neoplasias (PanINs) and insulin expressing islet ß-cells were reduced. Our data add further complexity to the interplay between Atg7 inhibition and Trp53 status in tumorigenesis.

18.
Autophagy ; 18(12): 2880-2893, 2022 12.
Article in English | MEDLINE | ID: mdl-35343375

ABSTRACT

The notion that macroautophagy/autophagy is a potentially attractive therapeutic target for a variety of diseases, including cancer, largely stems from pre-clinical mouse studies. Most of these examine the effects of irreversible and organ confined autophagy deletion using site specific Cre-loxP recombination of the essential autophagy regulating genes Atg7 or Atg5. Model systems with the ability to impair autophagy systemically and reversibly at all disease stages would allow a more realistic approach to evaluate the consequences of authophagy inhibition as a therapeutic concept and its potential side effects. Here, we present shRNA transgenic mice that via doxycycline (DOX) regulable expression of a highly efficient miR30-E-based shRNA enabled knockdown of Atg7 simultaneously in the majority of organs, with the brain and spleen being noteable exceptions. Induced animals deteriorated rapidly and experienced profound destruction of the exocrine pancreas, severe hypoglycemia and depletion of hepatic glycogen storages. Cessation of DOX application restored apparent health, glucose homeostasis and pancreatic integrity. In a similar Atg5 knockdown model we neither observed loss of pancreatic integrity nor diminished survival after DOX treatment, but identified histological changes consistent with steatohepatitis and hepatic fibrosis in the recovery period after termination of DOX. Regulable Atg7-shRNA mice are valuable tools that will enable further studies on the role of autophagy impairment at various disease stages and thereby help to evaluate the consequences of acute autophagy inhibition as a therapeutic concept.Abbreviations: ACTB: actin, beta; AMY: amylase complex; ATG4B: autophagy related 4B, cysteine peptidase; ATG5: autophagy related 5; ATG7: autophagy related 7; Cag: CMV early enhancer/chicken ACTB promoter; Col1a1: collagen, type I, alpha 1; Cre: cre recombinase; DOX: doxycycline; GCG: glucagon; GFP: green fluorescent protein; INS: insulin; LC3: microtubule-associated protein 1 light chain 3; miR30-E: optimized microRNA backbone; NAFLD: non-alcoholic fatty liver disease; NASH: non-alcoholic steatohepatitis; PNLIP: pancreatic lipase; rtTA: reverse tetracycline transactivator protein; SQSTM1/p62: sequestome 1; TRE: tetracycline responsive element.


Subject(s)
Autophagy-Related Protein 7 , Autophagy , Fatty Liver , Pancreas , Animals , Mice , Autophagy/genetics , Autophagy-Related Protein 7/genetics , Doxycycline , Mice, Transgenic , RNA, Small Interfering , Genes, Lethal , Pancreas/pathology , Gene Knockdown Techniques
19.
Histopathology ; 80(7): 1071-1080, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35322462

ABSTRACT

AIMS: To investigate Epstein-Barr virus (EBV) latency types in 19 cases of EBV-positive nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), as such information is currently incomplete. METHODS AND RESULTS: Immunohistochemistry (IHC) for CD20, CD79a, PAX5, OCT2, CD30, CD15, CD3 and programmed cell death protein 1 was performed. For EBV detection, in-situ hybridisation (ISH) for EBV-encoded RNA (EBER) was employed combined with IHC for EBV-encoded latent membrane protein (LMP)-1, EBV-encoded nuclear antigen (EBNA)-2, and EBV-encoded BZLF1. In 95% of the cases, neoplastic cells with features of Hodgkin and Reed-Sternberg (HRS) cells were present, mostly showing expression of CD30. In all cases, the B-cell phenotype was largely intact, and delineation from classic Hodgkin lymphoma (CHL) was further supported by myocyte enhancer factor 2B (MEF2B) detection. All tumour cells were EBER-positive except in two cases. EBV latency type II was most frequent (89%) and type I was rare. Cases with latency type I were CD30-negative. Five cases contained some BZLF1-positive and/or EBNA-2-positive bystander lymphocytes. CONCLUSIONS: As HRS morphology of neoplastic cells and CD30 expression are frequent features of EBV-positive NLPHL, preservation of the B-cell transcription programme, MEF2B expression combined with NLPHL-typical architecture and background composition facilitate distinction from CHL. EBER ISH is the method of choice to identify these cases. The majority present with EBV latency type II, and only rare cases present with latency type I, which can be associated with missing CD30 expression. The presence of occasional bystander lymphocytes expressing BZLF1 and/or EBNA-2 and the partial EBV infection of neoplastic cells in some cases could indicate that EBV is either not primarily involved or is only a transient driver in the pathogenesis of EBV-positive NLPHL.


Subject(s)
Epstein-Barr Virus Infections , Hodgkin Disease , Epstein-Barr Virus Infections/pathology , Herpesvirus 4, Human/genetics , Hodgkin Disease/pathology , Humans , Ki-1 Antigen/metabolism , Lymphocytes/pathology , Reed-Sternberg Cells/metabolism
20.
Br J Haematol ; 196(1): 116-126, 2022 01.
Article in English | MEDLINE | ID: mdl-34520052

ABSTRACT

High programmed cell death 1 ligand 1 (PD-L1) protein expression and copy number alterations (CNAs) of the corresponding genomic locus 9p24.1 in Hodgkin- and Reed-Sternberg cells (HRSC) have been shown to be associated with favourable response to anti-PD-1 checkpoint inhibition in relapsed/refractory (r/r) classical Hodgkin lymphoma (cHL). In the present study, we investigated baseline 9p24.1 status as well as PD-L1 and major histocompatibility complex (MHC) class I and II protein expression in 82 biopsies from patients with early stage unfavourable cHL treated with anti-PD-1-based first-line treatment in the German Hodgkin Study Group (GHSG) NIVAHL trial (ClinicalTrials.gov Identifier: NCT03004833). All evaluated specimens showed 9p24.1 CNA in HRSC to some extent, but with high intratumoral heterogeneity and an overall smaller range of alterations than reported in advanced-stage or r/r cHL. All but two cases (97%) showed PD-L1 expression by the tumour cells in variable amounts. While MHC-I was rarely expressed in >50% of HRSC, MHC-II expression in >50% of HRSC was found more frequently. No obvious impact of 9p24.1 CNA or PD-L1 and MHC-I/II expression on early response to the highly effective anti-PD-1-based NIVAHL first-line treatment was observed. Further studies evaluating an expanded panel of potential biomarkers are needed to optimally stratify anti-PD-1 first-line cHL treatment.


Subject(s)
B7-H1 Antigen/genetics , Chromosomes, Human, Pair 9 , Hodgkin Disease/diagnosis , Hodgkin Disease/etiology , Translocation, Genetic , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor , Combined Modality Therapy , DNA Copy Number Variations , Disease Management , Genetic Association Studies , Genetic Predisposition to Disease , Germany , Hodgkin Disease/mortality , Hodgkin Disease/therapy , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Prognosis , Treatment Outcome
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