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"Hovens, Christopher M"
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Tracking the origins and drivers of subclonal metastatic expansion in prostate cancer
by
Lunke, Sebastian
,
Rosenfeld, Nitzan
,
Ryan, Andrew
in
692/420/2489/68
,
692/699/67/322
,
692/699/67/589/466
2015
Tumour heterogeneity in primary prostate cancer is a well-established phenomenon. However, how the subclonal diversity of tumours changes during metastasis and progression to lethality is poorly understood. Here we reveal the precise direction of metastatic spread across four lethal prostate cancer patients using whole-genome and ultra-deep targeted sequencing of longitudinally collected primary and metastatic tumours. We find one case of metastatic spread to the surgical bed causing local recurrence, and another case of cross-metastatic site seeding combining with dynamic remoulding of subclonal mixtures in response to therapy. By ultra-deep sequencing end-stage blood, we detect both metastatic and primary tumour clones, even years after removal of the prostate. Analysis of mutations associated with metastasis reveals an enrichment of
TP53
mutations, and additional sequencing of metastases from 19 patients demonstrates that acquisition of
TP53
mutations is linked with the expansion of subclones with metastatic potential which we can detect in the blood.
Primary prostate tumours are known to be genetically heterogeneous and clonal selection has the potential to drive metastasis. Here Hong
et al
. show that the acquisition of TP53 mutations is linked to clonal expansion and metastatic progression to lethality.
Journal Article
An immune suppressive tumor microenvironment in primary prostate cancer promotes tumor immune escape
by
Neeson, Paul J.
,
Corcoran, Niall M.
,
Hutchinson, Ryan
in
Aged
,
Analysis
,
Antigen (tumor-associated)
2024
Immunotherapy has demonstrated limited activity in prostate cancer to date. This likely reflects an immune suppressive tumor microenvironment (TME), with previous studies suggesting low PD-L1 expression and a sparse immune cell infiltrate. We aimed to further characterise the immune TME in primary prostate cancer and correlate immune subset densities with clinical outcomes.
Two distinct cohorts of patients treated with radical prostatectomy were identified, based on the development of biochemical recurrence (BCR), one subgroup with high International Society of Urological Pathologists (ISUP) grade group, recurrent disease and a second with low grade, non-recurrent disease. A prostate immunohistochemical (IHC) antibody cocktail was used to differentiate tumor and peritumoral benign tissue. Specific CD8+, CD4+, FoxP3+, CD20+ and CD68+ cell subsets were identified using IHC staining of consecutive slides. PD-L1 and CD8/PD-L1 dual staining were also performed. Cell subset densities were quantified within tumor and peritumoral regions. We used descriptive statistics to report cell subset densities and T-tests to compare groups by age, grade and the development of BCR. Univariable and multivariable logistic regression were used to analyse risk factors for BCR and the development of metastatic disease.
A total of 175 patients were included, with a median age of 63 years and median pre-operative PSA of 8.2ng/ml. BCR occurred in 115 patients (66%) and 56 (32%) developed metastatic disease. CD68+ cells were the most abundant (median 648.8/mm2 intratumoral, 247.6/mm2 peritumoral), while PD-L1+ and PD-L1/CD8+ cell density was low overall (PD-L1+ median 162.4/mm2 intratumoral, 141.7/mm2 peritumoral; PD-L1/CD8+ (median 5.52/mm2 intratumoral, 3.41/mm2 peritumoral). Overall, grade group and T-stage were independently associated with BCR and metastatic disease. Higher density of peritumoral PD-L1+ cells was an independent risk factor for BCR (OR 5.33, 95%CI 1.31-21.61, p = 0.019).Although higher densities of CD8+ and CD4+ cells were observed in higher grade group 3-5 tumors, these were not associated with the development of BCR or metastasis.
In our cohort of prostate cancer patients who underwent radical prostatectomy, higher grade group and T-stage were independent predictors of BCR and metastasis. Despite higher grade group being associated with higher CD8+ cell density, PD-L1+ and PD-L1/CD8+ cell densities were low overall, suggesting lower T cell receptor recognition of tumor antigens. Further understanding of this phenomenon would influence development of future immunotherapeutic strategies in prostate cancer.
Journal Article
Perish and publish: Dynamics of biomedical publications by deceased authors
2022
The question of whether it is appropriate to attribute authorship to deceased individuals of original studies in the biomedical literature is contentious. Authorship guidelines utilized by journals do not provide a clear consensus framework that is binding on those in the field. To guide and inform the implementation of authorship frameworks it would be useful to understand the extent of the practice in the scientific literature, but studies that have systematically quantified the prevalence of this phenomenon in the biomedical literature have not been performed to date. To address this issue, we quantified the prevalence of publications by deceased authors in the biomedical literature from the period 1990–2020. We screened 2,601,457 peer-reviewed papers from the full text Europe PubMed Central database. We applied natural language processing, stringent filtering and manual curation to identify a final set of 1,439 deceased authors. We then determined these authors published a total of 38,907 papers over their careers with 5,477 published after death. The number of deceased publications has been growing rapidly, a 146-fold increase since the year 2000. This rate of increase was still significant when accounting for the growing total number of publications and pool of authors. We found that more than 50% of deceased author papers were first submitted after the death of the author and that over 60% of these papers failed to acknowledge the deceased authors status. Most deceased authors published less than 10 papers after death but a small pool of 30 authors published significantly more. A pool of 266 authors published more than 90% of their total publications after death. Our analysis indicates that the attribution of deceased authorship in the literature is not an occasional occurrence but a burgeoning trend. A consensus framework to address authorship by deceased scientists is warranted.
Journal Article
A urinary microRNA signature can predict the presence of bladder urothelial carcinoma in patients undergoing surveillance
by
Costello, Anthony J
,
Kowalczyk, Adam
,
Naeem, Haroon
in
631/337/384/331
,
692/699/67/1857
,
692/699/67/589/1336
2016
Background:
The objective of this study was to determine whether microRNA (miRNA) profiling of urine could identify the presence of urothelial carcinoma of the bladder (UCB) and to compare its performance characteristics to that of cystoscopy.
Methods:
In the discovery cohort we screened 81 patients, which included 21 benign controls, 30 non-recurrers and 30 patients with active cancer (recurrers), using a panel of 12 miRNAs. Data analysis was performed using a machine learning approach of a Support Vector Machine classifier with a Student’s
t
-test feature selection procedure. This was trained using a three-fold cross validation approach and performance was measured using the area under the receiver operator characteristic curve (AUC). The miRNA signature was validated in an independent cohort of a further 50 patients.
Results:
The best predictor to distinguish patients with UCB from non-recurrers was achieved using a combination of six miRNAs (AUC=0.85). This validated in an independent cohort (AUC=0.74) and detected UCB with a high sensitivity (88%) and sufficient specificity (48%) with all significant cancers identified. The performance of the classifier was best in detecting clinically significant disease such as presence of T1 Stage disease (AUC=0.92) and high-volume disease (AUC=0.81). Cystoscopy rates in the validation cohort would have been reduced by 30%.
Conclusions:
Urinary profiling using this panel of miRNAs shows promise for detection of tumour recurrence in the surveillance of UCB. Such a panel may be useful in reducing the morbidity and costs associated with cystoscopic surveillance, and now merits prospective evaluation.
Journal Article
Reducing the risk of false discovery enabling identification of biologically significant genome-wide methylation status using the HumanMethylation450 array
by
Pedersen, John S
,
Chatterton, Zac
,
Naeem, Haroon
in
Animal Genetics and Genomics
,
Biomedical and Life Sciences
,
Biotechnology industry
2014
Background
The Illumina HumanMethylation450 BeadChip (HM450K) measures the DNA methylation of 485,512 CpGs in the human genome. The technology relies on hybridization of genomic fragments to probes on the chip. However, certain genomic factors may compromise the ability to measure methylation using the array such as single nucleotide polymorphisms (SNPs), small insertions and deletions (INDELs), repetitive DNA, and regions with reduced genomic complexity. Currently, there is no clear method or pipeline for determining which of the probes on the HM450K bead array should be retained for subsequent analysis in light of these issues.
Results
We comprehensively assessed the effects of SNPs, INDELs, repeats and bisulfite induced reduced genomic complexity by comparing HM450K bead array results with whole genome bisulfite sequencing. We determined which CpG probes provided accurate or noisy signals. From this, we derived a set of high-quality probes that provide unadulterated measurements of DNA methylation.
Conclusions
Our method significantly reduces the risk of false discoveries when using the HM450K bead array, while maximising the power of the array to detect methylation status genome-wide. Additionally, we demonstrate the utility of our method through extraction of biologically relevant epigenetic changes in prostate cancer.
Journal Article
Detection of ctDNA in plasma of patients with clinically localised prostate cancer is associated with rapid disease progression
by
Corcoran, Niall M.
,
Ross, Mark T.
,
Kingsbury, Zoya
in
Bioinformatics
,
Biomarkers
,
Biomedical and Life Sciences
2020
Background
DNA originating from degenerate tumour cells can be detected in the circulation in many tumour types, where it can be used as a marker of disease burden as well as to monitor treatment response. Although circulating tumour DNA (ctDNA) measurement has prognostic/predictive value in metastatic prostate cancer, its utility in localised disease is unknown.
Methods
We performed whole-genome sequencing of tumour-normal pairs in eight patients with clinically localised disease undergoing prostatectomy, identifying high confidence genomic aberrations. A bespoke DNA capture and amplification panel against the highest prevalence, highest confidence aberrations for each individual was designed and used to interrogate ctDNA isolated from plasma prospectively obtained pre- and post- (24 h and 6 weeks) surgery. In a separate cohort (
n
= 189), we identified the presence of ctDNA
TP53
mutations in preoperative plasma in a retrospective cohort and determined its association with biochemical- and metastasis-free survival.
Results
Tumour variants in ctDNA were positively identified pre-treatment in two of eight patients, which in both cases remained detectable postoperatively. Patients with tumour variants in ctDNA had extremely rapid disease recurrence and progression compared to those where variants could not be detected. In terms of aberrations targeted, single nucleotide and structural variants outperformed indels and copy number aberrations. Detection of ctDNA
TP53
mutations was associated with a significantly shorter metastasis-free survival (6.2 vs. 9.5 years (HR 2.4; 95% CIs 1.2–4.8,
p
= 0.014).
Conclusions
CtDNA is uncommonly detected in localised prostate cancer, but its presence portends more rapidly progressive disease.
Journal Article
Curated MicroRNAs in Urine and Blood Fail to Validate as Predictive Biomarkers for High-Risk Prostate Cancer
by
Hong, Matthew K. H.
,
Lewis, Heather
,
Costello, Anthony J.
in
Aged
,
Aged, 80 and over
,
Analysis
2014
The purpose of this study was to determine if microRNA profiling of urine and plasma at radical prostatectomy can distinguish potentially lethal from indolent prostate cancer.
A panel of microRNAs was profiled in the plasma of 70 patients and the urine of 33 patients collected prior to radical prostatectomy. Expression of microRNAs was correlated to the clinical endpoints at a follow-up time of 3.9 years to identify microRNAs that may predict clinical response after radical prostatectomy. A machine learning approach was applied to test the predictive ability of all microRNAs profiled in urine, plasma, and a combination of both, and global performance assessed using the area under the receiver operator characteristic curve (AUC). Validation of urinary expression of miRNAs was performed on a further independent cohort of 36 patients.
The best predictor in plasma using eight miRs yielded only moderate predictive performance (AUC = 0.62). The best predictor of high-risk disease was achieved using miR-16, miR-21 and miR-222 measured in urine (AUC = 0.75). This combination of three microRNAs in urine was a better predictor of high-risk disease than any individual microRNA. Using a different methodology we found that this set of miRNAs was unable to predict high-volume, high-grade disease.
Our initial findings suggested that plasma and urinary profiling of microRNAs at radical prostatectomy may allow prognostication of prostate cancer behaviour. However we found that the microRNA expression signature failed to validate in an independent cohort of patients using a different platform for PCR. This highlights the need for independent validation patient cohorts and suggests that urinary microRNA signatures at radical prostatectomy may not be a robust way to predict the course of clinical disease after definitive treatment for prostate cancer.
Journal Article
Phase II randomised placebo-controlled trial of sodium selenate as a disease-modifying treatment in chronic drug-resistant temporal lobe epilepsy: the SeLECT study protocol
by
Nicolo, John-Paul
,
Johns, Hannah
,
Shultz, Sandy R
in
Biomarkers
,
clinical trial
,
Clinical trials
2023
IntroductionEpilepsy is one of the most common neurological conditions worldwide. Despite many antiseizure medications (ASMs) being available, up to one-third of patients do not achieve seizure control. Preclinical studies have shown treatment with sodium selenate to have a disease-modifying effect in a rat model of chronic temporal lobe epilepsy (TLE).AimThis randomised placebo-controlled trial aims to evaluate the antiseizure and disease-modifying effects of sodium selenate in people with drug-resistant TLE.MethodsThis will be a randomised placebo-controlled trial of sodium selenate. One hundred and twenty-four adults with drug-resistant TLE and ≥4 countable seizures/month will be recruited. Outcomes of interest will be measured at baseline, week 26 and week 52 and include an 8-week seizure diary, 24-hour electroencephalogram and cognitive, neuropsychiatric and quality of life measures. Participants will then be randomised to receive a sustained release formulation of sodium selenate (initially 10 mg three times a day, increasing to 15 mg three times a day at week 4 if tolerated) or a matching placebo for 26 weeks.OutcomesThe primary outcome will be a consumer codesigned epilepsy-Desirability of Outcome Rank (DOOR), combining change in seizure frequency, adverse events, quality of life and ASM burden measures into a single outcome measure, compared between treatment arms over the whole 52-week period. Secondary outcomes will compare baseline measures to week 26 (antiseizure) and week 52 (disease modification). Exploratory measures will include biomarkers of treatment response.Ethics and disseminationThe study has been approved by the lead site, Alfred Hospital Ethics Committee (594/20). Each participant will provide written informed consent prior to any trial procedures. The results of the study will be presented at national and international conferences, published in peer-reviewed journals and disseminated through consumer organisations.ConclusionThis study will be the first disease-modification randomised controlled trial in patients with drug-resistant TLE.Trial registration numberANZCTR; ACTRN12623000446662.
Journal Article
Brain‐derived tau to measure treatment effect in Alzheimer's disease and frontotemporal dementia
by
Marotta, Cassandra
,
Turton, Michael
,
O'Brien, Terence J.
in
Alzheimer's disease
,
anti-tau treatment
,
Atrophy
2025
INTRODUCTION Brain‐derived tau (BD‐tau) measures tau specifically from brain‐derived sources and can differentiate Alzheimer's disease (AD) from other diseases. This study investigated BD‐tau as a potential biomarker of treatment effect. METHODS BD‐tau and phosphorylated tau‐217 (p‐tau217) levels were measured after treatment with an anti‐tau drug in AD and behavioral variant frontotemporal dementia (bvFTD) clinical trials, and the association with total tau (t‐tau), p‐tau181, and amyloid beta 42 (Aβ42) was examined. RESULTS Cerebrospinal fluid (CSF) BD‐tau decreased after treatment in the AD cohort; however, no change was seen in bvFTD or p‐tau217 in either cohort. CSF t‐tau and p‐tau181 correlated with BD‐tau in AD (r = 0.9113 and 0.7746, p < 0.0001) and bvFTD (r = 1.0 and r = 0.79, p < 0.05). CSF BD‐tau did not correlate with serum or plasma BD‐tau in bvFTD. DISCUSSION CSF BD‐tau shows potential as a biomarker of treatment effect in AD but not bvFTD. Further research is needed to investigate this effect in blood‐based samples and in other neurodegenerative diseases. Trial registration: ACTRN12611001200976, ACTRN12617001218381. Highlights Cerebrospinal fluid (CSF) brain‐derived tau (BD‐tau) levels decreased with sodium selenate treatment in patients with Alzheimer's disease (AD). CSF BD‐tau levels did not change with sodium selenate treatment in bvFTD. Baseline CSF BD‐tau correlated with CSF total tau (t‐tau) and phosphorylated tau‐181 (p‐tau181) in AD and behavioral variant frontotemporal dementia (bvFTD). Baseline serum and plasma BD‐tau levels did not correlate with CSF BD‐tau in bvFTD. CSF p‐tau217 did not change with sodium selenate treatment in AD or bvFTD.
Journal Article
A study protocol for a phase II randomised, double-blind, placebo-controlled trial of sodium selenate as a disease-modifying treatment for behavioural variant frontotemporal dementia
by
O'Brien, Terence J
,
Churilov, Leonid
,
Malpas, Charles B
in
Australia
,
Biomarkers
,
Brain research
2020
IntroductionBehavioural variant frontotemporal dementia (bvFTD) is a neurodegenerative disorder often neuropathologically associated with the accumulation of abnormally hyperphosphorylated tau, for which there is currently no disease-modifying treatment. Previous work by our group has shown sodium selenate upregulates the activity of protein phosphatase 2 in the brain, increasing the rate of tau dephosphorylation. The objective of this study is to evaluate the efficacy and safety of sodium selenate as a disease-modifying treatment for bvFTD.Methods and analysisThis will be a multisite, phase IIb, double-blind placebo-controlled trial of sodium selenate. One hundred and twenty participants will be enrolled across 4 Australian academic hospitals. Following screening eligible participants will be randomised (1:1) to sodium selenate (15 mg three times a day) or placebo for 52 weeks. Participants will have regular safety and efficacy visits throughout the study period. The primary study outcome will be percentage brain volume change (PBVC) as measured on MRI over 52 weeks of treatment. This will be analysed with a general linear model (analysis of covariance (ANCOVA)) with the PBVC as an output, the treatment as an input and the baseline brain volume as covariate for adjustment purposes. Secondary outcomes include safety and tolerability measures, and efficacy measures; change in cerebrospinal fluid total-tau, Addenbrooke’s Cognitive Examination-III and Cambridge Behavioural Inventory-Revised scores over the 52 weeks of treatment. These will also be analysed with ANCOVA where the corresponding baseline measure will be incorporated in the model. Additional exploratory outcomes will include other imaging, cognitive and biospecimen analyses.Ethics and disseminationThe study was approved by the Human Research and Ethics Committee of the lead site as part of the Australian Multisite Ethics approval system. The results of the study will be presented at national and international conferences and published in peer-reviewed journals.Trial registration numberACTRN12620000236998 .
Journal Article