Highlights d Clock-like mutation process attributed to APOBEC3 mediates earliest mutations in PC d Identification of four molecular subgroups that stratifies intermediate-risk disease d Rearrangements at the ESRP1 locus associated with aggressive and proliferative cancer d Development of method to predict clinical trajectories of PC from DNA sequencing data
Despite much evidence on epigenetic abnormalities in cancer, it is currently unclear to what extent epigenetic alterations can be associated with tumors' clonal genetic origins. Here, we show that the prostate intratumor heterogeneity in DNA methylation and copy-number patterns can be explained by a unified evolutionary process. By assaying multiple topographically distinct tumor sites, premalignant lesions, and lymph node metastases within five cases of prostate cancer, we demonstrate that both DNA methylation and copy-number heterogeneity consistently reflect the life history of the tumors. Furthermore, we show cases of genetic or epigenetic convergent evolution and highlight the diversity in the evolutionary origins and aberration spectrum between tumor and metastatic subclones. Importantly, DNA methylation can complement genetic data by serving as a proxy for activity at regulatory domains, as we show through identification of high epigenetic heterogeneity at androgen-receptor-bound enhancers. Epigenome variation thereby expands on the current genome-centric view on tumor heterogeneity.
Despite a multitude of p53 immunohistochemistry (IHC) studies, data on the combined effect of nuclear p53 protein accumulation and TP53 genomic inactivation are lacking for prostate cancer. A tissue microarray including 11,152 prostate cancer samples was analyzed by p53 IHC and fluorescence in situ hybridization. Nuclear p53 accumulation was found in 10.1% of patients including 1.4% with high-level and 8.7% with low-level immunostaining. TP53 sequencing revealed that 17 of 22 (77%) cases with high-level p53 immunostaining, but only 3% (1 of 31) low-level p53 cases carried putative dominantnegative mutations. TP53 deletions occurred in 14.8% of cancers. Both deletions and protein accumulation were linked to unfavorable tumor phenotype and prostate specific antigen (PSA) recurrence (p < 0.0001 each). The combination of both methods revealed subgroups with remarkable differences in their clinical course. Tumors with either TP53 deletion (14%) or lowlevel p53 positivity (8.7%) had identical risks of PSA recurrence, which were markedly higher than in cancers without p53 alterations (p < 0.0001). Tumors with both p53 deletion and low-level p53 positivity (1.5%) had a worse prognosis than patients with only one of these alterations (p < 0.0001). Tumors with strong p53 immunostaining or homozygous inactivation through deletion of one allele and disrupting translocation involving the second allele had the worst outcome, independent from clinical and pathological parameters. These data demonstrate a differential clinical impact of various TP53 alterations in prostate cancer. Strong p53 immunostaining-most likely accompanying dominant negative or oncogenic p53 mutation-has independent prognostic relevance and may thus represent a clinical useful molecular feature of prostate cancer.Dysregulation of the p53 tumor suppressor belongs to the most frequent genetic alterations in malignant tumors. Reduced p53 function compromises cellular programs inducing apoptosis in DNA damaged cells and consequently enables tumor progression through acquisition of additional genetic changes. Mechanisms for TP53 inactivation include functionally relevant point mutations of the gene as well as gross chromosomal alterations, mostly 17p deletions. Disrupting breaks of the TP53 gene have only recently been described as an alternative mechanism for p53 inactivation. 1 Furthermore, at least certain p53 mutations can exhibit oncogenic properties through mutation-specific protein interactions that may be independent of the physiological gene function. For example, transgenic mice with particular p53 mutations develop a spectrum of primary cancers and metastases that is more aggressive and phenotypically different from those observed in mice with a p53-null allele. 2 Irrespective of their functional consequences, tumorigenic p53 mutations frequently accompany markedly increased levels of altered p53 protein in affected cells. 3 Immunohistochemistry (IHC) is thus commonly used to detect p53-mutated cancers.In prostate cancer, p53 alterations are less c...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.