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1.
N Engl J Med ; 2024 May 25.
Article in English | MEDLINE | ID: mdl-38804514

ABSTRACT

BACKGROUND: Antibody-mediated rejection is a leading cause of kidney-transplant failure. The targeting of CD38 to inhibit graft injury caused by alloantibodies and natural killer (NK) cells may be a therapeutic option. METHODS: In this phase 2, double-blind, randomized, placebo-controlled trial, we assigned patients with antibody-mediated rejection that had occurred at least 180 days after transplantation to receive nine infusions of the CD38 monoclonal antibody felzartamab (at a dose of 16 mg per kilogram of body weight) or placebo for 6 months, followed by a 6-month observation period. The primary outcome was the safety and side-effect profile of felzartamab. Key secondary outcomes were renal-biopsy results at 24 and 52 weeks, donor-specific antibody levels, peripheral NK-cell counts, and donor-derived cell-free DNA levels. RESULTS: A total of 22 patients underwent randomization (11 to receive felzartamab and 11 to receive placebo). The median time from transplantation until trial inclusion was 9 years. Mild or moderate infusion reactions occurred in 8 patients in the felzartamab group. Serious adverse events occurred in 1 patient in the felzartamab group and in 4 patients in the placebo group; graft loss occurred in 1 patient in the placebo group. After week 24, resolution of morphologic antibody-mediated rejection was more frequent with felzartamab (in 9 of 11 patients [82%]) than with placebo (in 2 of 10 patients [20%]), for a difference of 62 percentage points (95% confidence interval [CI], 19 to 100) and a risk ratio of 0.23 (95% confidence interval [CI], 0.06 to 0.83). The median microvascular inflammation score was lower in the felzartamab group than in the placebo group (0 vs. 2.5), for a mean difference of -1.95 (95% CI, -2.97 to -0.92). Also lower was a molecular score reflecting the probability of antibody-mediated rejection (0.17 vs. 0.77) and the level of donor-derived cell-free DNA (0.31% vs. 0.82%). At week 52, the recurrence of antibody-mediated rejection was reported in 3 of 9 patients who had a response to felzartamab, with an increase in molecular activity and biomarker levels toward baseline levels. CONCLUSIONS: Felzartamab had acceptable safety and side-effect profiles in patients with antibody-mediated rejection. (Funded by MorphoSys and Human Immunology Biosciences; ClinicalTrials.gov number, NCT05021484; and EUDRACT number, 2021-000545-40.).

3.
Nat Rev Nephrol ; 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38632381

ABSTRACT

The kidney epithelium, with its intricate arrangement of highly specialized cell types, constitutes the functional core of the organ. Loss of kidney epithelium is linked to the loss of functional nephrons and a subsequent decline in kidney function. In kidney transplantation, epithelial injury signatures observed during post-transplantation surveillance are strong predictors of adverse kidney allograft outcomes. However, epithelial injury is currently neither monitored clinically nor addressed therapeutically after kidney transplantation. Several factors can contribute to allograft epithelial injury, including allograft rejection, drug toxicity, recurrent infections and postrenal obstruction. The injury mechanisms that underlie allograft injury overlap partially with those associated with acute kidney injury (AKI) and chronic kidney disease (CKD) in the native kidney. Studies using advanced transcriptomic analyses of single cells from kidney or urine have identified a role for kidney injury-induced epithelial cell states in exacerbating and sustaining damage in AKI and CKD. These epithelial cell states and their associated expression signatures are also observed in transplanted kidney allografts, suggesting that the identification and characterization of transcriptomic epithelial cell states in kidney allografts may have potential clinical implications for diagnosis and therapy.

4.
Transplantation ; 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38538559

ABSTRACT

BACKGROUND: Plasma donor-derived cell-free DNA (dd-cfDNA) is used to screen for rejection in heart transplants. We launched the Trifecta-Heart study (ClinicalTrials.gov No. NCT04707872), an investigator-initiated, prospective trial, to examine the correlations between genome-wide molecular changes in endomyocardial biopsies (EMBs) and plasma dd-cfDNA. The present report analyzes the correlation of plasma dd-cfDNA with gene expression in EMBs from 4 vanguard centers and compared these correlations with those in 604 kidney transplant biopsies in the Trifecta-Kidney study (ClinicalTrials.gov No. NCT04239703). METHODS: We analyzed 137 consecutive dd-cfDNA-EMB pairs from 70 patients. Plasma %dd-cfDNA was measured by the Prospera test (Natera Inc), and gene expression in EMBs was assessed by Molecular Microscope Diagnostic System using machine-learning algorithms to interpret rejection and injury states. RESULTS: Top transcripts correlating with dd-cfDNA were related to genes increased in rejection such as interferon gamma-inducible genes (eg, HLA-DMA ) but also with genes induced by injury and expressed in macrophages (eg, SERPINA1 and HMOX1 ). In gene enrichment analysis, the top dd-cfDNA-correlated genes reflected inflammation and rejection pathways. Dd-cfDNA correlations with rejection genes in EMB were similar to those seen in kidney transplant biopsies, with somewhat stronger correlations for TCMR genes in hearts and ABMR genes in kidneys. However, the correlations with parenchymal injury-induced genes and macrophage genes were much stronger in hearts. CONCLUSIONS: In this first analysis of Trifecta-Heart study, dd-cfDNA correlates significantly with molecular rejection but also with injury and macrophage infiltration, reflecting the proinflammatory properties of injured cardiomyocytes. The relationship supports the utility of dd-cfDNA in clinical management of heart transplant recipients.

5.
Am J Transplant ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38527588

ABSTRACT

The first-generation Molecular Microscope (MMDx) system for heart transplant endomyocardial biopsies used expression of rejection-associated transcripts (RATs) to diagnose not only T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR) but also acute injury. However, the ideal system should detect rejection without being influenced by injury, to permit analysis of the relationship between rejection and parenchymal injury. To achieve this, we developed a new rejection classification in an expanded cohort of 3230 biopsies: 1641 from INTERHEART (ClinicalTrials.gov NCT02670408), plus 1589 service biopsies added to improve the power of the machine learning algorithms. The new system used 6 rejection classifiers instead of RATs and generated 7 rejection archetypes: No rejection, 48%; Minor, 24%; TCMR1, 2.3%; TCMR2, 2.7%; TCMR/mixed, 2.7%; early-stage ABMR, 3.9%; and fully developed ABMR, 16%. Using rejection classifiers eliminated cross-reactions with acute injury, permitting separate assessment of rejection and injury. TCMR was associated with severe-recent injury and late atrophy-fibrosis and rarely had normal parenchyma. ABMR was better tolerated, seldom producing severe injury, but in later biopsies was often associated with atrophy-fibrosis, indicating long-term risk. Graft survival and left ventricular ejection fraction were reduced not only in hearts with TCMR but also in hearts with severe-recent injury and atrophy-fibrosis, even without rejection.

7.
Sci Rep ; 14(1): 2720, 2024 02 01.
Article in English | MEDLINE | ID: mdl-38302657

ABSTRACT

Here, we establish a CT-radiomics based method for application in invasive, orthotopic rodent brain tumour models. Twenty four NOD/SCID mice were implanted with U87R-Luc2 GBM cells and longitudinally imaged via contrast enhanced (CE-CT) imaging. Pyradiomics was employed to extract CT-radiomic features from the tumour-implanted hemisphere and non-tumour-implanted hemisphere of acquired CT-scans. Inter-correlated features were removed (Spearman correlation > 0.85) and remaining features underwent predictive analysis (recursive feature elimination or Boruta algorithm). An area under the curve of the receiver operating characteristic curve was implemented to evaluate radiomic features for their capacity to predict defined outcomes. Firstly, we identified a subset of radiomic features which distinguish the tumour-implanted hemisphere and non- tumour-implanted hemisphere (i.e, tumour presence from normal tissue). Secondly, we successfully translate preclinical CT-radiomic pipelines to GBM patient CT scans (n = 10), identifying similar trends in tumour-specific feature intensities (E.g. 'glszm Zone Entropy'), thereby suggesting a mouse-to-human species conservation (a conservation of radiomic features across species). Thirdly, comparison of features across timepoints identify features which support preclinical tumour detection earlier than is possible by visual assessment of CT scans. This work establishes robust, preclinical CT-radiomic pipelines and describes the application of CE-CT for in-depth orthotopic brain tumour monitoring. Overall we provide evidence for the role of pre-clinical 'discovery' radiomics in the neuro-oncology space.


Subject(s)
Brain Neoplasms , Radiomics , Humans , Animals , Mice , Mice, Inbred NOD , Mice, SCID , Brain Neoplasms/diagnostic imaging , Tomography, X-Ray Computed/methods
8.
Transplantation ; 108(1): 45-71, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37310258

ABSTRACT

This review outlines the molecular disease states in kidney transplant biopsies as documented in the development of the Molecular Microscope Diagnostic System (MMDx). These states include T cell-mediated rejection (TCMR), antibody-mediated rejection (AMR), recent parenchymal injury, and irreversible atrophy-fibrosis. The MMDx project, initiated through a Genome Canada grant, is a collaboration involving many centers. MMDx uses genome-wide microarrays to measure transcript expression, interprets the results using ensembles of machine learning algorithms, and generates a report. Experimental studies in mouse models and cell lines were extensively used to annotate molecular features and interpret the biopsy results. Over time, MMDx revealed unexpected aspects of the disease states: for example, AMR is usually C4d-negative and often DSA-negative, and subtle "Minor" AMR-like states are frequent. Parenchymal injury correlates with both reduced glomerular filtration rate and increased risk of graft loss. In kidneys with rejection, injury features, not rejection activity, are the strongest predictors of graft survival. Both TCMR and AMR produce injury, but TCMR induces immediate nephron injury and accelerates atrophy-fibrosis, whereas AMR induces microcirculation and glomerular damage that slowly leads to nephron failure and atrophy-fibrosis. Plasma donor-derived cell-free DNA levels correlate strongly with AMR activity, acute kidney injury, and in a complex way with TCMR activity. Thus, the MMDx project has documented the molecular processes that underlie the clinical and histologic states in kidney transplants, and provides a diagnostic tool that can be used to calibrate biomarkers, optimize histology interpretation, and guide clinical trials.


Subject(s)
Kidney Transplantation , Animals , Mice , Kidney Transplantation/adverse effects , Kidney/pathology , Antibodies , Phenotype , Fibrosis , Atrophy/etiology , Atrophy/pathology , Graft Rejection/diagnosis , Biopsy
9.
Transplantation ; 108(2): 445-454, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37726883

ABSTRACT

BACKGROUND: The Banff system for histologic diagnosis of rejection in kidney transplant biopsies uses guidelines to assess designated features-lesions, donor-specific antibody (DSA), and C4d staining. We explored whether using regression equations to interpret the features as well as current guidelines could establish the relative importance of each feature and improve histologic interpretation. METHODS: We developed logistic regression equations using the designated features to predict antibody-mediated rejection (AMR/mixed) and T-cell-mediated rejection (TCMR/mixed) in 1679 indication biopsies from the INTERCOMEX study ( ClinicalTrials.gov NCT01299168). Equations were trained on molecular diagnoses independent of the designated features. RESULTS: In regression and random forests, the important features predicting molecular rejection were as follows: for AMR, ptc and g, followed by cg; for TCMR, t > i. V-lesions were relatively unimportant. C4d and DSA were also relatively unimportant for predicting AMR: by AUC, the model excluding them (0.853) was nearly as good as the model including them (0.860). Including time posttransplant slightly but significantly improved all models. By AUC, regression predicted molecular AMR and TCMR better than Banff histologic diagnoses. More importantly, in biopsies called "no rejection" by Banff guidelines, regression equations based on histology features identified histologic and molecular rejection-related changes in some biopsies and improved survival predictions. Thus, regression can screen for missed rejection. CONCLUSIONS: Using lesion-based regression equations in addition to Banff histology guidelines defines the relative important of histology features for identifying rejection, allows screening for potential missed diagnoses, and permits early estimates of AMR when C4d and DSA are not available.


Subject(s)
Kidney Transplantation , Kidney Transplantation/adverse effects , Graft Rejection , Graft Survival , Antibodies , T-Lymphocytes , Biopsy
10.
Am J Transplant ; 24(3): 338-349, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38032300

ABSTRACT

The XVI-th Banff Meeting for Allograft Pathology was held at Banff, Alberta, Canada, from 19th to 23rd September 2022, as a joint meeting with the Canadian Society of Transplantation. To mark the 30th anniversary of the first Banff Classification, premeeting discussions were held on the past, present, and future of the Banff Classification. This report is a summary of the meeting highlights that were most important in terms of their effect on the Classification, including discussions around microvascular inflammation and biopsy-based transcript analysis for diagnosis. In a postmeeting survey, agreement was reached on the delineation of the following phenotypes: (1) "Probable antibody-mediated rejection (AMR)," which represents donor-specific antibodies (DSA)-positive cases with some histologic features of AMR but below current thresholds for a definitive AMR diagnosis; and (2) "Microvascular inflammation, DSA-negative and C4d-negative," a phenotype of unclear cause requiring further study, which represents cases with microvascular inflammation not explained by DSA. Although biopsy-based transcript diagnostics are considered promising and remain an integral part of the Banff Classification (limited to diagnosis of AMR), further work needs to be done to agree on the exact classifiers, thresholds, and clinical context of use.


Subject(s)
Kidney Transplantation , Humans , Complement C4b , Canada , Kidney/pathology , Inflammation/pathology , Isoantibodies , Biopsy
11.
J Heart Lung Transplant ; 43(3): 508-518, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38042442

ABSTRACT

BACKGROUND: We explored the changes in gene expression correlating with dysfunction and graft failure in endomyocardial biopsies. METHODS: Genome-wide microarrays (19,462 genes) were used to define mRNA changes correlating with dysfunction (left ventricular ejection fraction [LVEF] ≤ 55) and risk of graft loss within 3 years postbiopsy. LVEF data was available for 1,013 biopsies and survival data for 779 patients (74 losses). Molecular classifiers were built for predicting dysfunction (LVEF ≤ 55) and postbiopsy 3-year survival. RESULTS: Dysfunction is correlated with dedifferentiation-decreased expression of normal heart transcripts, for example, solute carriers, along with increased expression of inflammation genes. Many genes with reduced expression in dysfunction were matrix genes such as fibulin 1 and decorin. Gene ontology (GO) categories suggested matrix remodeling and inflammation, not rejection. Genes associated with the risk of failure postbiopsy overlapped dysfunction genes but also included genes affecting microcirculation, for example, arginase 2, which reduces NO production, and endothelin 1. GO terms also reflected increased glycolysis and response to hypoxia, but decreased VEGF and angiogenesis pathways. T cell-mediated rejection was associated with reduced survival and antibody-mediated rejection with relatively good survival, but the main determinants of survival were features of parenchymal injury. Both dysfunction and graft loss were correlated with increased biopsy expression of BNP (gene NPPB). Survival probability classifiers divided hearts into risk quintiles, with actuarial 3-year postbiopsy survival >95% for the highest versus 50% for the lowest. CONCLUSIONS: Dysfunction in transplanted hearts reflects dedifferentiation, decreased matrix genes, injury, and inflammation. The risk of short-term loss includes these changes but is also associated with microcirculation abnormalities, glycolysis, and response to hypoxia.


Subject(s)
Heart Transplantation , Ventricular Function, Left , Humans , Stroke Volume , Hypoxia , Inflammation
12.
Am J Transplant ; 24(5): 743-754, 2024 May.
Article in English | MEDLINE | ID: mdl-38097018

ABSTRACT

Antibody-mediated rejection (ABMR) is a leading cause of graft failure. Emerging evidence suggests a significant contribution of natural killer (NK) cells to microvascular inflammation (MVI). We investigated the influence of genetically determined NK cell functionality on ABMR development and activity. The study included 86 kidney transplant recipients subjected to systematic biopsies triggered by donor-specific antibody detection. We performed killer immunoglobulin-like receptor typing to predict missing self and genotyped polymorphisms determining NK cell functionality (FCGR3AV/F158 [rs396991], KLRC2wt/del, KLRK1HNK/LNK [rs1049174], rs9916629-C/T). Fifty patients had ABMR with considerable MVI and elevated NK cell transcripts. Missing self was not related to MVI. Only KLRC2wt/wt showed an association (MVI score: 2 [median; interquartile range: 0-3] vs 0 [0-1] in KLRC2wt/del recipients; P = .001) and remained significant in a proportional odds multivariable model (odds ratio, 7.84; 95% confidence interval, 2.37-30.47; P = .001). A sum score incorporating all polymorphisms and missing self did not outperform a score including only KLRC2 and FCGR3A variants, which were predictive in univariable analysis. NK cell genetics did not affect graft functional decline and survival. In conclusion, a functional KLRC2 polymorphism emerged as an independent determinant of ABMR activity, without a considerable contribution of missing self and other NK cell gene polymorphisms.


Subject(s)
Graft Rejection , Graft Survival , Inflammation , Isoantibodies , Kidney Transplantation , Killer Cells, Natural , Tissue Donors , Humans , Killer Cells, Natural/immunology , Graft Rejection/immunology , Graft Rejection/etiology , Graft Rejection/pathology , Kidney Transplantation/adverse effects , Male , Female , Middle Aged , Tissue Donors/supply & distribution , Isoantibodies/immunology , Prognosis , Inflammation/immunology , Follow-Up Studies , Graft Survival/immunology , Adult , Risk Factors , Microvessels/pathology , Microvessels/immunology , Genotype , Kidney Failure, Chronic/surgery , Kidney Failure, Chronic/immunology , Kidney Failure, Chronic/genetics , Kidney Function Tests , Biomarkers/analysis , Biomarkers/metabolism
13.
Transplantation ; 108(4): 898-910, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38150492

ABSTRACT

BACKGROUND: Among all biopsies in the Trifecta-Kidney Study ( ClinicalTrials.gov NCT04239703), elevated plasma donor-derived cell-free DNA (dd-cfDNA) correlated most strongly with molecular antibody-mediated rejection (AMR) but was also elevated in other states: T cell-mediated rejection (TCMR), acute kidney injury (AKI), and some apparently normal biopsies. The present study aimed to define the molecular correlates of plasma dd-cfDNA within specific states. METHODS: Dd-cfDNA was measured by the Prospera test. Molecular rejection and injury states were defined using the Molecular Microscope system. We studied the correlation between dd-cfDNA and the expression of genes, transcript sets, and classifier scores within specific disease states, and compared AMR, TCMR, and AKI to biopsies classified as normal and no injury (NRNI). RESULTS: In all 604 biopsies, dd-cfDNA was elevated in AMR, TCMR, and AKI. Within AMR biopsies, dd-cfDNA correlated with AMR activity and stage. Within AKI, the correlations reflected acute parenchymal injury, including cell cycling. Within biopsies classified as MMDx Normal and archetypal No injury (NRNI), dd-cfDNA still correlated significantly with rejection- and injury-related genes. TCMR activity (eg, the TCMR Prob classifier) correlated with dd-cfDNA, but within TCMR biopsies, top gene correlations were complex and not the top TCMR-selective genes. CONCLUSIONS: In kidney transplants, elevated plasma dd-cfDNA is associated with 3 distinct molecular states in the donor tissue: AMR, recent parenchymal injury (including cell cycling), and TCMR, potentially complicated by parenchymal disruption. Moreover, subtle rejection- and injury-related changes in the donor tissue can contribute to dd-cfDNA elevations in transplants considered to have no rejection or injury.


Subject(s)
Acute Kidney Injury , Cell-Free Nucleic Acids , Kidney Transplantation , Humans , Kidney Transplantation/adverse effects , Antibodies , Tissue Donors , Cell-Free Nucleic Acids/genetics , Graft Rejection/genetics
14.
Neurosurg Rev ; 46(1): 295, 2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37940745

ABSTRACT

Only a limited number of studies have focused on the results of the Endoscopic Endonasal Approach (EEA) for treatment of prolactinomas. We sought to assess the effectiveness of EEA for prolactinoma surgery, identify factors for disease remission, and present our approach for the management of persistent disease. Forty-seven prolactinomas operated over 10 years, with a mean follow-up of 59.9 months, were included. The primary endpoints were early disease remission and remission at last follow-up. Resistance/intolerance to DA were surgical indications in 76.7%. Disease remission was achieved in 80% of microprolactinomas and 100% of microprolactinomas enclosed by the pituitary. Early disease remission was correlated with female gender (p=0.03), lower preoperative PRL levels (p=0.014), microadenoma (p=0.001), lack of radiological hemorrhage (p=0.001), absence of cavernous sinus (CS) invasion (p<0.001), and extent of resection (EOR) (p<0.001). Persistent disease was reported in 48.9% of patients, with 47% of them achieving remission at last follow-up with DA therapy alone. Repeat EEA and/or radiotherapy were utilized in 6 patients, with 66.7% achieving remission. Last follow-up remission was achieved in 76.6%, with symptomatic improvement in 95.8%. Factors predicting last follow-up remission were no previous operation (p=0.001), absence of CS invasion (p=0.01), and EOR (p<0.001). Surgery is effective for disease control in microprolactinomas. In giant and invasive tumors, it may significantly reduce the tumor volume. A multidisciplinary approach may lead to long-term disease control in three-quarters of patients, with symptomatic improvement in an even greater proportion.


Subject(s)
Pituitary Neoplasms , Prolactinoma , Humans , Female , Prolactinoma/surgery , Prolactinoma/pathology , Pituitary Neoplasms/surgery , Pituitary Neoplasms/pathology , Prognosis , Treatment Outcome , Retrospective Studies
15.
Acta Neurochir (Wien) ; 165(12): 3585-3592, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37971621

ABSTRACT

BACKGROUND: Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated (HA) diarrhoea, contributing to patient morbidity and prolonged length-of-stay (LOS). We retrospectively assessed CDI over a decade in a national neurosurgical centre, with a multi-disciplinary approach to CDI surveillance and antimicrobial stewardship, by comparing CDI patients with other patient groups. METHODS: Data on CDI in neurosurgical inpatients between January 2012 and December 2021 were collated. Disease-specific variables were compared to other inpatients with CDI. Rates per 10,000 bed days used were calculated. Patient-specific differences were compared with neurosurgical patients without CDI. CDI rates by patient group were explored using odds ratio (OR) and χ2 analyses. Negative binomial regression was used to investigate CDI rates over time. RESULTS: Of 50 neurosurgical patients with CDI, all were HA; the average age was 53 years (standard deviation (SD) 16.3 years), 49 were first-episode CDI, and three had severe CDI. The majority (76.7%) had received recent antimicrobials. Compared with non-neurosurgical CDI patients, neurosurgical CDI rates differed significantly (1.9 versus 3.6 per 10,000 bed days used, p < 0.05), neurosurgical patients were younger (p ≤ 0.01), C. difficile testing was more likely to be requested by neurosurgeons (OR 2.4; p ≤ 0.01), and the proportion of severe CDI was higher (6% versus 2%, OR 3.0, p = 0.07, confidence interval (CI) 0.54 to 11.3). Within the neurosurgical cohort, CDI patients had an average LOS four times that of other patients (CI 15.2 to 35.1; p < 0.01) and were older (53.5 versus 47.8 years, CI 0.1 to 11 years; p < 0.05). Only one CDI outbreak was linked to neurosurgical patients. CONCLUSION: CDI in neurosurgery patients differed from the wider hospital, with greater awareness of CDI testing. Longer LOS impacted bed utilisation with limited capacity. Robust surveillance supports proactive antimicrobial stewardship programmes in this vulnerable population.


Subject(s)
Clostridioides difficile , Clostridium Infections , Cross Infection , Humans , Middle Aged , Length of Stay , Retrospective Studies , Inpatients , Clostridium Infections/epidemiology , Cross Infection/epidemiology
16.
Cell Death Dis ; 14(10): 705, 2023 10 28.
Article in English | MEDLINE | ID: mdl-37898609

ABSTRACT

Medulloblastoma is the most common malignant paediatric brain tumour, representing 20% of all paediatric intercranial tumours. Current aggressive treatment protocols and the use of radiation therapy in particular are associated with high levels of toxicity and significant adverse effects, and long-term sequelae can be severe. Therefore, improving chemotherapy efficacy could reduce the current reliance on radiation therapy. Here, we demonstrated that systems-level analysis of basal apoptosis protein expression and their signalling interactions can differentiate between medulloblastoma cell lines that undergo apoptosis in response to chemotherapy, and those that do not. Combining computational predictions with experimental BH3 profiling, we identified a therapeutically-exploitable dependence of medulloblastoma cells on BCL-XL, and experimentally validated that BCL-XL targeting, and not targeting of BCL-2 or MCL-1, can potentiate cisplatin-induced cytotoxicity in medulloblastoma cell lines with low sensitivity to cisplatin treatment. Finally, we identified MCL-1 as an anti-apoptotic mediator whose targeting is required for BCL-XL inhibitor-induced apoptosis. Collectively, our study identifies that BCL-XL and MCL-1 are the key anti-apoptotic proteins in medulloblastoma, which mediate distinct protective roles. While BCL-XL has a first-line role in protecting cells from apoptosis basally, MCL-1 represents a second line of defence that compensates for BCL-XL upon its inhibition. We provide rationale for the further evaluation of BCL-XL and MCL-1 inhibitors in the treatment of medulloblastoma, and together with current efforts to improve the cancer-specificity of BCL-2 family inhibitors, these novel treatment strategies have the potential to improve the future clinical management of medulloblastoma.


Subject(s)
Antineoplastic Agents , Cerebellar Neoplasms , Medulloblastoma , Humans , Child , Apoptosis Regulatory Proteins/metabolism , Myeloid Cell Leukemia Sequence 1 Protein/metabolism , bcl-X Protein/metabolism , Medulloblastoma/drug therapy , Medulloblastoma/genetics , Cisplatin/pharmacology , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Apoptosis , Antineoplastic Agents/pharmacology , Cerebellar Neoplasms/drug therapy , Cerebellar Neoplasms/genetics , Cell Line, Tumor
17.
Am J Transplant ; 23(12): 1922-1938, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37295720

ABSTRACT

In lung transplantation, antibody-mediated rejection (AMR) diagnosed using the International Society for Heart and Lung Transplantation criteria is uncommon compared with other organs, and previous studies failed to find molecular AMR (ABMR) in lung biopsies. However, understanding of ABMR has changed with the recognition that ABMR in kidney transplants is often donor-specific antibody (DSA)-negative and associated with natural killer (NK) cell transcripts. We therefore searched for a similar molecular ABMR-like state in transbronchial biopsies using gene expression microarray results from the INTERLUNG study (#NCT02812290). After optimizing rejection-selective transcript sets in a training set (N = 488), the resulting algorithms separated an NK cell-enriched molecular rejection-like state (NKRL) from T cell-mediated rejection (TCMR)/Mixed in a test set (N = 488). Applying this approach to all 896 transbronchial biopsies distinguished 3 groups: no rejection, TCMR/Mixed, and NKRL. Like TCMR/Mixed, NKRL had increased expression of all-rejection transcripts, but NKRL had increased expression of NK cell transcripts, whereas TCMR/Mixed had increased effector T cell and activated macrophage transcripts. NKRL was usually DSA-negative and not recognized as AMR clinically. TCMR/Mixed was associated with chronic lung allograft dysfunction, reduced one-second forced expiratory volume at the time of biopsy, and short-term graft failure, but NKRL was not. Thus, some lung transplants manifest a molecular state similar to DSA-negative ABMR in kidney and heart transplants, but its clinical significance must be established.


Subject(s)
Kidney Transplantation , Lung Transplantation , Killer Cells, Natural , Kidney Transplantation/adverse effects , Kidney/pathology , Biopsy , Lung Transplantation/adverse effects , Antibodies , Graft Rejection/diagnosis , Graft Rejection/etiology
18.
J Neurooncol ; 163(1): 269-279, 2023 May.
Article in English | MEDLINE | ID: mdl-37165117

ABSTRACT

PURPOSE: Neurosurgery (NS) is an essential modality for large brain metastases (BM). Postoperative stereotactic radiosurgery (SRS) is the standard of care adjuvant treatment. Pachymeningeal failure (PMF) is a newly described entity, distinct from classical leptomeningeal failure (LMF), that is uniquely observed in postoperative patients treated with adjuvant SRS. We sought to identify risk factors for PMF in patients treated with NS + SRS. METHODS: From a prospective registry (2009 to 2021), we identified all patients treated with NS + SRS. Clinical, imaging, pathological, and treatment factors were analyzed. PMF incidence was evaluated using a competing risks model. RESULTS: 144 Patients were identified. The median age was 62 (23-90). PMF occurred in 21.5% (31/144). Female gender [Hazard Ratio (HR) 2.65, p = 0.013], higher Graded Prognostic Assessment (GPA) index (HR 2.4, p < 0.001), absence of prior radiation therapy (HR N/A, p = 0.018), controlled extracranial disease (CED) (HR 3.46, p = 0.0038), and pia/dura contact (PDC) (HR 3.30, p = 0.0053) were associated with increased risk for PMF on univariate analysis. In patients with PDC, wider target volumes correlated with reduced risk of PMF. Multivariate analysis indicated PDC (HR 3.51, p = 0.0053), piecemeal resection (HR 2.38, p = 0.027), and CED (HR 3.97, p = 0.0016) independently correlated with PMF risk. PMF correlated with reduced OS (HR 2.90, p < 0.001) at a lower rate compared to LMF (HR 10.15, p < 0.001). CONCLUSION: PMF correlates with tumor PDC and piecemeal resection in patients treated with NS + SRS. For unclear reasons, it is also associated with CED. In tumors with PDC, wider dural radiotherapy coverage was associated with a lower risk of PMF.


Subject(s)
Brain Neoplasms , Radiosurgery , Humans , Male , Female , Brain Neoplasms/radiotherapy , Brain Neoplasms/secondary , Brain Neoplasms/surgery , Postoperative Complications , Adult , Middle Aged , Aged , Aged, 80 and over , Treatment Outcome , Meningeal Neoplasms/radiotherapy , Meningeal Neoplasms/secondary
19.
J Neurooncol ; 163(2): 327-338, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37237151

ABSTRACT

BACKGROUND: Glioblastoma (GBM) is an aggressive brain cancer that typically results in death in the first 15 months after diagnosis. There have been limited advances in finding new treatments for GBM. In this study, we investigated molecular differences between patients with extremely short (≤ 9 months, Short term survivors, STS) and long survival (≥ 36 months, Long term survivors, LTS). METHODS: Patients were selected from an in-house cohort (GLIOTRAIN-cohort), using defined inclusion criteria (Karnofsky score > 70; age < 70 years old; Stupp protocol as first line treatment, IDH wild type), and a multi-omic analysis of LTS and STS GBM samples was performed. RESULTS: Transcriptomic analysis of tumour samples identified cilium gene signatures as enriched in LTS. Moreover, Immunohistochemical analysis confirmed the presence of cilia in the tumours of LTS. Notably, reverse phase protein array analysis (RPPA) demonstrated increased phosphorylated GAB1 (Y627), SRC (Y527), BCL2 (S70) and RAF (S338) protein expression in STS compared to LTS. Next, we identified 25 unique master regulators (MR) and 13 transcription factors (TFs) belonging to ontologies of integrin signalling and cell cycle to be upregulated in STS. CONCLUSION: Overall, comparison of STS and LTS GBM patients, identifies novel biomarkers and potential actionable therapeutic targets for the management of GBM.


Subject(s)
Brain Neoplasms , Glioblastoma , Humans , Aged , Glioblastoma/pathology , Prognosis , Brain Neoplasms/pathology , Brain/pathology , Survivors
20.
Transplantation ; 107(5): 1027-1041, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36944603

ABSTRACT

Today we know that both the humoral and the cellular arm of the immune system are engaged in severe immunological challenges. A close interaction between B and T cells can be observed in most "natural" challenges, including infections, malignancies, and autoimmune diseases. The importance and power of humoral immunity are impressively demonstrated by the current coronavirus disease 2019 pandemic. Organ transplant rejection is a normal immune response to a completely "artificial" challenge. It took a long time before the multifaceted action of different immunological forces was recognized and a unified, generally accepted opinion could be formed. Here, we address prominent paradigms and paradigm shifts in the field of transplantation immunology. We identify several instances in which the transplant community missed a timely paradigm shift because essential, available knowledge was ignored. Moreover, we discuss key findings that critically contributed to our understanding of transplant immunology but sometimes developed with delay and in a roundabout way, as was the case with antibody-mediated rejection-a main focus of this article. These include the discovery of the molecular principles of histocompatibility, the recognition of the microcirculation as a key interface of immune damage, the refinement of alloantibody detection, the description of C4d as a footmark of endothelium-bound antibody, and last but not least, the developments in biopsy-based diagnostics beyond conventional morphology, which only now give us a glimpse of the enormous complexity and pathogenetic diversity of rejection.


Subject(s)
COVID-19 , Organ Transplantation , Humans , Isoantibodies , Graft Rejection , Organ Transplantation/adverse effects , Transplantation Immunology
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