42 research outputs found
A philosophical analysis of the evidence-based medicine debate
BACKGROUND: The term "evidence-based medicine" (or EBM) was introduced about ten years ago, and there has been considerable debate about the value of EBM. However, this debate has sometimes been obscured by a lack of conceptual clarity concerning the nature and status of EBM. DISCUSSION: First, we note that EBM proponents have obscured the current debate by defining EBM in an overly broad, indeed almost vacuous, manner; we offer a clearer account of EBM and its relation to the alternative approaches to medicine. Second, while EBM proponents commonly cite the philosophical work of Thomas Kuhn and claim that EBM is a Kuhnian 'paradigm shift,' we argue that such claims are seriously mistaken and unduly polarize the EBM debate. Third, we suggest that it is much more fruitful to understand the relationship between EBM and its alternatives in light of a different philosophical metaphor: W.V. Quine's metaphor of the web of belief. Seen in this way, we argue that EBM is an approach to medical practice that is indeed importantly different from the alternatives. SUMMARY: We can have a more productive debate about the value of EBM by being clearer about the nature of EBM and its relationship to alternative approaches to medicine
Genome-wide interrogation of structural variation reveals novel African-specific prostate cancer oncogenic drivers
ADDITIONAL FILE 1: FIGURE S1. Concordant SV call generation from Manta
and GRIDSS. FIGURE S2. Summary of SVs in each type, compared to other
studies. FIGURE S3. CIRCOS plot of hyper-SV mutated tumours. FIGURE S4. The spread of SV breakpoints and samples in each 1 Mbp genomic bin. FIGURE S5. TMPRSS2-ERG fusion with interstitial region retention.
TABLE S1. Clinical and pathological characteristics of 180 prostate cancer
patients included in this study. TABLE S2. Biallelic assessment of CDK12
in hyper-duplicated samples. TABLE S3. Biallelic assessment of BRCA2 in
hyper-deleted samples.ADDITIONAL FILE 2: TABLE S4. Summary of gene fusions identified from SVs.
ADDITIONAL FILE 3: TABLE S5. SV calls resulting in gene fusions.DATA AND MATERIALS AVAILABILITY : The datasets analysed in this study were obtained and accessible through
Jaratlerdsiri et al [6], with sequence data deposited in the European GenomePhenome Archive (EGA; https://ega-archive.org) under overarching accession
EGAS00001006425 and including the Southern African Prostate Cancer Study
(SAPCS) Dataset (EGAD00001009067) and Garvan/St Vincent’s Prostate Cancer
Database (EGAD00001009066). The computational code used to analyse SV
subtypes, SV hotspots and gene fusions is available on GitHub [68].BACKGROUND : African ancestry is a significant risk factor for advanced prostate cancer (PCa). Mortality rates in sub-
Saharan Africa are 2.5-fold greater than global averages. However, the region has largely been excluded from the
benefits of whole genome interrogation studies. Additionally, while structural variation (SV) is highly prevalent, PCa
genomic studies are still biased towards small variant interrogation.
METHODS : Using whole genome sequencing and best practice workflows, we performed a comprehensive analysis
of SVs for 180 (predominantly Gleason score ≥ 8) prostate tumours derived from 115 African, 61 European and four
ancestrally admixed patients. We investigated the landscape and relationship of somatic SVs in driving ethnic disparity
(African versus European), with a focus on African men from southern Africa.
RESULTS : Duplication events showed the greatest ethnic disparity, with a 1.6- (relative frequency) to 2.5-fold (count)
increase in African-derived tumours. Furthermore, we found duplication events to be associated with CDK12 inactivation
and MYC copy number gain, and deletion events associated with SPOP mutation. Overall, African-derived
tumours were 2-fold more likely to present with a hyper-SV subtype. In addition to hyper-duplication and deletion
subtypes, we describe a new hyper-translocation subtype. While we confirm a lower TMPRSS2-ERG fusion-positive rate
in tumours from African cases (10% versus 33%), novel African-specific PCa ETS family member and TMPRSS2 fusion
partners were identified, including LINC01525, FBXO7, GTF3C2, NTNG1 and YPEL5. Notably, we found 74 somatic SV
hotspots impacting 18 new candidate driver genes, with CADM2, LSAMP, PTPRD, PDE4D and PACRG having therapeutic
implications for African patients.
CONCLUSIONS : In this first African-inclusive SV study for high-risk PCa, we demonstrate the power of SV interrogation
for the identification of novel subtypes, oncogenic drivers and therapeutic targets. Identifying a novel spectrum of SVs
in tumours derived from African patients provides a mechanism that may contribute, at least in part, to the observed
ethnic disparity in advanced PCa presentation in men of African ancestry.The Medical Health and Medical Research Council (NHMRC) of Australia, University of Sydney Bridging Grant, the USA. Department of Defense (DoD) Prostate Cancer Research Program (PCRP) Idea Development.https://genomemedicine.biomedcentral.comam2023School of Health Systems and Public Health (SHSPH
African-specific molecular taxonomy of prostate cancer
Data availability
DNA-sequencing data have been deposited at the European Genome-
Phenome Archive (EGA) under overarching accession EGAS00001006425
and including the Southern African Prostate Cancer Study (SAPCS)
Dataset (EGAD00001009067 and Garvan/St Vincent’s Prostate Cancer
Database EGAD00001009066). Academic researchers meeting the
data-access policy criteria may apply for data access through the
respective data access committees. CPGEA data are available through
http://www.cpgea.com. PCAWG data are available at ICGC Data Portal
(https://dcc.icgc.org/releases/PCAWG).Prostate cancer is characterized by considerable geo-ethnic disparity. African ancestry is a significant risk factor, with mortality rates across sub-Saharan Africa of 2.7-fold higher than global averages. The contributing genetic and non-genetic factors, and associated mutational processes, are unknown. Here, through whole-genome sequencing of treatment-naive prostate cancer samples from 183 ancestrally (African versus European) and globally distinct patients, we generate a large cancer genomics resource for sub-Saharan Africa, identifying around 2 million somatic variants. Significant African-ancestry-specific findings include an elevated tumour mutational burden, increased percentage of genome alteration, a greater number of predicted damaging mutations and a higher total of mutational signatures, and the driver genes NCOA2, STK19, DDX11L1, PCAT1 and SETBP1. Examining all somatic mutational types, we describe a molecular taxonomy for prostate cancer differentiated by ancestry and defined as global mutational subtypes (GMS). By further including Chinese Asian data, we confirm that GMS-B (copy-number gain) and GMS-D (mutationally noisy) are specific to African populations, GMS-A (mutationally quiet) is universal (all ethnicities) and the African–European-restricted subtype GMS-C (copy-number losses) predicts poor clinical outcomes. In addition to the clinical benefit of including individuals of African ancestry, our GMS subtypes reveal different evolutionary trajectories and mutational processes suggesting that both common genetic and environmental factors contribute to the disparity between ethnicities. Analogous to gene–environment interaction—defined here as a different effect of an environmental surrounding in people with different ancestries or vice versa—we anticipate that GMS subtypes act as a proxy for intrinsic and extrinsic mutational processes in cancers, promoting global inclusion in landmark studies.The National Health and Medical Research Council (NHMRC) of Australia, NHMRC Ideas Grants, University of Sydney Bridging Grant, the US Department of Defense (DoD) Prostate Cancer Research Program (PCRP) Idea Development Award TARGET Africa.http://www.nature.com/natuream2023School of Health Systems and Public Health (SHSPH