17 research outputs found
DNA-PKcs-Mediated Transcriptional Regulation Drives Prostate Cancer Progression and Metastasis.
Emerging evidence demonstrates that the DNA repair kinase DNA-PKcs exerts divergent roles in transcriptional regulation of unsolved consequence. Here, in vitro and in vivo interrogation demonstrate that DNA-PKcs functions as a selective modulator of transcriptional networks that induce cell migration, invasion, and metastasis. Accordingly, suppression of DNA-PKcs inhibits tumor metastases. Clinical assessment revealed that DNA-PKcs is significantly elevated in advanced disease and independently predicts for metastases, recurrence, and reduced overall survival. Further investigation demonstrated that DNA-PKcs in advanced tumors is highly activated, independent of DNA damage indicators. Combined, these findings reveal unexpected DNA-PKcs functions, identify DNA-PKcs as a potent driver of tumor progression and metastases, and nominate DNA-PKcs as a therapeutic target for advanced malignancies
Novel Oncogenic Transcription Factor Cooperation in RB-Deficient Cancer
The retinoblastoma tumor suppressor (RB) is a critical regulator of E2F-dependent transcription, controlling a multitude of protumorigenic networks including but not limited to cell-cycle control. Here, genome-wide assessment of E2F1 function after RB loss in isogenic models of prostate cancer revealed unexpected repositioning and cooperation with oncogenic transcription factors, including the major driver of disease progression, the androgen receptor (AR). Further investigation revealed that observed AR/E2F1 cooperation elicited novel transcriptional networks that promote cancer phenotypes, especially as related to evasion of cell death. These observations were reflected in assessment of human disease, indicating the clinical relevance of the AR/E2F1 cooperome in prostate cancer. Together, these studies reveal new mechanisms by which RB loss induces cancer progression and highlight the importance of understanding the targets of E2F1 function. SIGNIFICANCE: This study identifies that RB loss in prostate cancer drives cooperation between AR and E2F1 as coregulators of transcription, which is linked to the progression of advanced disease
A Novel Role for DNA-PK in Metabolism by Regulating Glycolysis in Castration Resistant Prostate Cancer
Published first January 24, 2022.Purpose: DNA-dependent protein kinase catalytic subunit (DNA-PKcs, herein referred as DNA-PK) is a multifunctional kinase of high cancer relevance. DNA-PK is deregulated in multiple tumor types, including prostate cancer, and is associated with poor outcomes. DNA-PK was previously nominated as a therapeutic target and DNA-PK inhibitors are currently undergoing clinical investigation. Although DNA-PK is well studied in DNA repair and transcriptional regulation, much remains to be understood about the way by which DNA-PK drives aggressive disease phenotypes. Experimental Design: Here, unbiased proteomic and metabolomic approaches in clinically relevant tumor models uncovered a novel role of DNA-PK in metabolic regulation of cancer progression. DNA-PK regulation of metabolism was interrogated using pharmacologic and genetic perturbation using in vitro cell models, in vivo xenografts, and ex vivo in patient-derived explants (PDE). Results: Key findings reveal: (i) the first-in-field DNA-PK protein interactome; (ii) numerous DNA-PK novel partners involved in glycolysis; (iii) DNA-PK interacts with, phosphorylates (in vitro), and increases the enzymatic activity of glycolytic enzymes ALDOA and PKM2; (iv) DNA-PK drives synthesis of glucosederived pyruvate and lactate; (v) DNA-PK regulates glycolysis in vitro, in vivo, and ex vivo; and (vi) combination of DNA-PK inhibitor with glycolytic inhibitor 2-deoxyglucose leads to additive anti-proliferative effects in aggressive disease. Conclusions: Findings herein unveil novel DNA-PK partners, substrates, and function in prostate cancer. DNA-PK impacts glycolysis through direct interaction with glycolytic enzymes and modulation of enzymatic activity. These events support energy production that may contribute to generation and/or maintenance of DNA-PK–mediated aggressive disease phenotypes.Emanuela Dylgjeri, Vishal Kothari, Ayesha A. Shafi, Galina Semenova, Peter T. Gallagher, Yi F. Guan, Angel Pang, Jonathan F. Goodwin, Swati Irani, Jennifer J. McCann, Amy C. Mandigo, Saswati Chand, Christopher M. McNair, Irina Vasilevskaya, MatthewJ. Schiewer, Costas D. Lallas, Peter A. McCue, Leonard G. Gomella, Erin L. Seifert, Jason S. Carroll, Lisa M. Butler, Jeff Holst, William K. Kelly, and Karen E. Knudse
The circadian cryptochrome, CRY1, is a pro-tumorigenic factor that rhythmically modulates DNA repair.
Mechanisms regulating DNA repair processes remain incompletely defined. Here, the circadian factor CRY1, an evolutionally conserved transcriptional coregulator, is identified as a tumor specific regulator of DNA repair. Key findings demonstrate that CRY1 expression is androgen-responsive and associates with poor outcome in prostate cancer. Functional studies and first-in-field mapping of the CRY1 cistrome and transcriptome reveal that CRY1 regulates DNA repair and the G2/M transition. DNA damage stabilizes CRY1 in cancer (in vitro, in vivo, and human tumors ex vivo), which proves critical for efficient DNA repair. Further mechanistic investigation shows that stabilized CRY1 temporally regulates expression of genes required for homologous recombination. Collectively, these findings reveal that CRY1 is hormone-induced in tumors, is further stabilized by genomic insult, and promotes DNA repair and cell survival through temporal transcriptional regulation. These studies identify the circadian factor CRY1 as pro-tumorigenic and nominate CRY1 as a new therapeutic target
Risk factors associated with short-term complications in mandibular fractures: the MANTRA study—a Maxillofacial Trainee Research Collaborative (MTReC)
Abstract Introduction Complications following mandibular fractures occur in 9–23% of patients. Identifying those at risk is key to prevention. Previous studie
Risk factors associated with short-term complications in mandibular fractures: the MANTRA study—a Maxillofacial Trainee Research Collaborative (MTReC)
Abstract
Introduction
Complications following mandibular fractures occur in 9–23% of patients. Identifying those at risk is key to prevention. Previous studies highlighted smoking, age and time from injury to presentation as risk factors but rarely recorded other possible confounders. In this paper, we use a collaborative snapshot audit to document novel risk factors and confirm established risks for complications following the treatment of mandibular fractures.
Methods
The audit was carried out by 122 OMFS trainees across the UK and Ireland (49 centres) over 6Â months, coordinated by the Maxillofacial Surgery Trainees Research Collaborative. Variables recorded included basic demography, medical and social history, injury mechanism and type, management and 30-day outcome.
Results
Nine hundred and forty-seven (947) patients with fractured mandibles were recorded. Surgical management was carried out in 76.3%. Complications at 30Â days occurred 65 (9%) of those who were managed surgically. Risk factors for complications included male sex, increasing age, any medical history, increasing number of cigarettes smoked per week, increasing alcohol use per week, worse oral hygiene and increased time from injury to presentation.
Discussion
We have used a large prospective snapshot audit to confirm established risk factors and identify novel risk factors. We demonstrate that time from injury to presentation is confounded by other indicators of poor health behaviour. These results are important in designing trial protocols for management of mandibular fractures and in targeting health interventions to patients at highest risk of complications.
</jats:sec
FUNCTIONAL MRI IN MALFORMATIONS OF CORTICAL DEVELOPMENT: ACTIVATION OF DYSPLASTIC TISSUE AND FUNCTIONAL REORGANIZATION.
BACKGROUND AND PURPOSE: Functional neuroimaging and electrophysiological studies suggest that dysplastic neural tissue in malformations of cortical development may participate in task performance, and that functional organization can be altered beyond visible lesion boundaries. The aim of this work was to investigate cortical function in a heterogeneous group of patients with malformations of cortical development. METHODS: Twelve patients participated in the study, 2 for each of the following categories: subcortical, periventricular, and band heterotopia, unilateral and bilateral polymicrogyria, and focal cortical dysplasia. Functional magnetic resonance imaging was performed with finger tapping, somatosensory and visual stimulation, and language-related tasks. RESULTS: We found activations within the dysplastic tissue in subcortical heterotopia, band heterotopia, and polymicrogyria, but not in periventricular heterotopic nodules. In one of the patients with focal cortical dysplasia, language-related activation involved part of the lesion. Functional reorganization beyond visible lesion boundaries was seen, with different patterns, in 4 patients. CONCLUSIONS: In accordance with previous reports, our findings indicate that dysplastic neural tissue can be activated during task performance, and that in some patients, extensive functional reorganization occurs, highlighting the importance of functional magnetic resonance imaging in presurgical planning in those patients for whom epilepsy surgery is considered as an option