High levels of 5-hydroxymethylcytosine (5hmC) is an adverse predictor of biochemical recurrence after prostatectomy in ERG-negative prostate cancer

Abstract

BackgroundProstate cancer (PC) can be stratified into distinct molecular subtypes based on TMPRSS2-ERG gene fusion status, but its potential prognostic value remains controversial. Likewise, routine clinicopathological features cannot clearly distinguish aggressive from indolent tumors at the time of diagnosis; thus, new prognostic biomarkers are urgently needed. The DNA methylation variant 5-hydroxymethylcytosine (5hmC, an oxidized derivative of 5-methylcytosine) has recently emerged as a new diagnostic and/or prognostic biomarker candidate for several human malignancies. However, this remains to be systematically investigated for PC. In this study, we determined 5hmC levels in 311 PC (stratified by ERG status) and 228 adjacent non-malignant (NM) prostate tissue specimens by immunohistochemical analysis of a tissue microarray, representing a large radical prostatectomy (RP) cohort with long clinical follow-up. We investigated possible correlations between 5hmC and routine clinicopathological variables and assessed the prognostic potential of 5hmC by Kaplan-Meier and uni- and multivariate Cox regression analyses in ERG+ (n = 178) vs. ERG− (n = 133) PCs using biochemical recurrence (BCR) as endpoint.ResultsWe observed a borderline significant (p = 0.06) reduction in 5hmC levels in PC compared to NM tissue samples, which was explained by a highly significant (p < 0.001) loss of 5hmC in ERG− PCs. ERG status was not predictive of BCR in this cohort (p = 0.73), and no significant association was found between BCR and 5hmC levels in ERG+ PCs (p = 0.98). In contrast, high 5hmC immunoreactivity was a significant adverse predictor of BCR after RP in ERG− PCs, independent of Gleason score, pathological tumor stage, surgical margin status, and pre-operative prostate-specific antigen (PSA) level (hazard ratio (HR) (95 % confidence interval (CI)): 1.62 (1.15–2.28), p = 0.006).ConclusionsThis is the first study to demonstrate a prognostic potential for 5hmC in PC. Our findings highlight the importance of ERG stratification in PC biomarker studies and suggest that epigenetic mechanisms involving 5hmC are important for the development and/or progression of ERG− PC.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-015-0146-5) contains supplementary material, which is available to authorized users.

Epigenetics Reactivation of Nrf2 in Prostate TRAMP C1 Cells by Curcumin Analogue FN1

“…8, 44–46 Hence, DNA methyltransferases (DNMTs) and histone deacetylases (HDACs), which induce DNA methylation and histone acetylation modification and gene expression silencing are becoming new targets for prostate cancer prevention and therapy. 17, 47–49 We previously reported that Nrf2 is epigenetically silenced by hypermethylation of the first five CpG islands during prostate cancer development in TRAMP mice and TRAMP-C1 cells.…”

DNA Methylation and Hydroxymethylation in Cervical Cancer: Diagnosis, Prognosis and Treatment

“…Genome-wide DNA hydroxymethylation has been considered a sensitive biomarker for prostate cancer (PCa) detection. Owing to the loss of hydroxymethylation, different cancers maintain low levels of 5-hmC (Feng et al, 2015;Strand et al, 2015;Kamdar et al, 2016;Spans et al, 2016). However, Grelus et al (2017) have shown that hydroxymethylation markers cannot be single biomarkers for PCa diagnosis.…”

Low 5-hydroxymethylcytosine level is an independent predictor of high histological grade in locally advanced breast cancer

“…These data together suggest that the alteration of 5hmC could potentially contribute to tumorigenesis and progression of tumors [32]. In the clinical setting, low levels of 5hmC have been associated with poor outcomes, such as long-term prognosis and early recurrence, in different solid tumor cancers, including kidney cancer, esophageal cancer, and breast cancer [34][35][36][37].…”