Brett Delahunt

Brett Delahunt


Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 December 2018 in Histopathology
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Journal Article
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BDBrett Delahunt
Brett Delahunt
JEJohn N Eble
John N Eble
LELars Egevad
Lars Egevad
HSHemamali Samaratunga
Hemamali Samaratunga

18 July 2017 in Histopathology
Verified
Journal Article
Closed access
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JDJulien Dagher
Julien Dagher
BDBrett Delahunt
Brett Delahunt
NRNathalie Rioux‐Leclercq
Nathalie Rioux‐Leclercq
LELars Egevad
Lars Egevad
JSJohn R Srigley
John R Srigley
HSHemamali Samaratunga
Hemamali Samaratunga

1 September 2020 in Journal of Clinical Pathology
Verified
Journal Article
Open access
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MTMichelle Thunders
Michelle Thunders
BDBrett Delahunt
Brett Delahunt
Transmembrane serine protease 2 is encoded by the TMPRSS2 gene. The gene is widely conserved and has two isoforms, both being autocatalytically activated from the inactive zymogen form. A fusion gene between the TMPRSS2 gene and ERG (erythroblast-specific-related gene), an oncogenic transcription factor, is the most common chromosomal aberration detected in prostate cancer, responsible for driving carcinogenesis. The other key role of TMPRSS2 is in priming the viral spike protein which facilitates viral entry essential for viral infectivity. The protease activates a diverse range of viruses. Both SARS-CoV and SARS-CoV-2 (COVID-19) use angiotensin-converting enzyme 2 (ACE2) and TMPRSS2 to facilitate entry to cells, but with SARS-CoV-2 human-to-human transmission is much higher than SARS-CoV. As TMPRSS2 is expressed outside of the lung, and can therefore contribute to extrapulmonary spread of viruses, it warrants further exploration as a potential target for limiting viral spread and infectivity.

1 January 2021 in Pathology
Verified
Journal Article
Closed access
BDBrett Delahunt
Brett Delahunt
JEJohn N. Eble
John N. Eble
HSHemamali Samaratunga
Hemamali Samaratunga
MTMichelle Thunders
Michelle Thunders
JYJohn W. Yaxley
John W. Yaxley
LELars Egevad
Lars Egevad

8 December 2020 in Journal of Clinical Pathology
Verified
Journal Article
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MTMichelle Thunders
Michelle Thunders
BDBrett Delahunt
Brett Delahunt
DICER1 is a highly conserved RNaseIII endoribonuclease that has a critical role in the biogenesis of microRNAs (miRNAs). miRNAs are small regulatory RNAs responsible for post-transcriptional gene silencing, controlling more than half of human protein-coding genes. This is achieved through the targeting and regulation of complementary RNA transcripts and has a well-documented role in post-transcriptional gene regulation and transposon repression. DICER1 deficiency results in dysregulation of miRNAs, changing the expression of many genes. DICER1 syndrome represents a collection of benign and malignant tumours arising from an autosomally inherited germline mutation leading to an inherited predisposition to cancer. The syndrome represents an unusual form of Knudson’s two-hit hypothesis, where individuals with a pathogenic germline DICER1 variant acquire a second trans-somatic missense DICER1 mutation. This somatic mutation appears to have to occur in one of five hotspots codons and may contribute towards the incomplete penetrance observed within DICER1 syndrome families. In this case, DICER1 is haploinsuffcient with only one deletion required and partial loss of function being advantageous to tumours over complete loss of function. As increasing data emerge reaffirming the pivotal role of DICER1 in the maintenance of human physiology, DICER1 is likely to become an increasingly attractive target for novel therapeutic strategies.

17 March 2022 in European Journal of Nuclear Medicine and Molecular Imaging
Verified
Journal Article
Open access
PDF file
MRMatthew J Roberts
Matthew J Roberts
AMAndrew Morton
Andrew Morton
NPNathan Papa
Nathan Papa
AFAnthony Franklin
Anthony Franklin
SRSheliyan Raveenthiran
Sheliyan Raveenthiran
JYJohn W. Yaxley
John W. Yaxley
Purpose: The prognostic value of PSMA intensity on PSMA PET/CT due to underlying biology and subsequent clinical implications is an emerging topic of interest. We sought to investigate whether primary tumour PSMA PET intensity contributes to pre- and post-operative prediction of oncological outcomes following radical prostatectomy. Methods: We performed a retrospective cohort study of 848 men who underwent all of multiparametric MRI (mpMRI), transperineal prostate biopsy, and 68 Ga-PSMA PET/CT prior to radical prostatectomy. PSMA intensity, quantified as maximum standard uptake value (SUVmax), and other clinical variables were considered relative to post-operative biochemical recurrence-free survival (BRFS) using Cox regression and Kaplan–Meier analysis. Results: After a median follow-up of 41 months, 219 events occurred; the estimated 3-year BRFS was 79% and the 5-year BRFS was 70%. Increasing PSMA intensity was associated with less favourable BRFS overall (Log rank p < 0.001), and within subgroups of Gleason score category (Log rank p < 0.03). PSMA intensity was significantly associated with shorter time to biochemical recurrence, after adjusting for pre-operative (HR per 5-unit SUVmax increase = 1.15) and post-operative (HR per 5-unit SUVmax increase = 1.10) parameters. Conclusion: These results in a large series of patients confirm PSMA intensity to be a novel, independent prognostic factor for BRFS.