Udali Silvia, De Santis Domenica, Mazzi Filippo, Moruzzi Sara, Ruzzenente Andrea, Castagna Annalisa, Pattini Patrizia, Beschin Greta, Franceschi Antonia, Guglielmi Alfredo, Martinelli Nicola, Pizzolo Francesca, Ambrosani Francesca, Olivieri Oliviero, Choi Sang-Woon, Friso Simonetta
Department of Medicine, University of Verona, Verona, Italy.
Department of Surgery, University of Verona, Verona, Italy.
Front Oncol. 2021 Jan 28;10:596040. doi: 10.3389/fonc.2020.596040. eCollection 2020.
Mechanisms underlying hepatocellular carcinoma (HCC) development are largely unknown. The role of trace elements and proteins regulating metal ions homeostasis, i.e. metallothioneins (MTs), recently gained an increased interest. Object of the study was to investigate the role of promoter DNA methylation in MTs transcriptional regulation and the possible prognostic significance of serum trace elements in HCC.
Forty-nine HCC patients were enrolled and clinically characterized. Cu, Se, and Zn contents were measured by Inductively Coupled Plasma Mass Spectrometry in the serum and, for a subset of 27 patients, in HCC and homologous non-neoplastic liver (N) tissues. and gene expression in hepatic tissues was assessed by Real-Time RT-PCR and the specific promoter DNA methylation by Bisulfite-Amplicon Sequencing.
Patients with Cu serum concentration above the 80 percentile had a significantly decreased survival rate (P < 0.001) with a marked increased hazard ratio for mortality (HR 6.88 with 95% CI 2.60-18.23, P < 0.001). Se and Zn levels were significantly lower in HCC as compared to N tissues (P < 0.0001). and gene expression was significantly down-regulated in HCC as compared to N tissues (P < 0.05). MTs promoter was hypermethylated in 9 out of the 19 HCC tissues showing MTs down-regulation and methylation levels of three specific CpGs paralleled to an increased mortality rate among the 23 patients analyzed (P = 0.015).
and act as potential tumor suppressor genes regulated through promoter DNA methylation and, together with serum Cu concentrations, be related to survival rate in HCC.
肝细胞癌（HCC）发生的机制在很大程度上尚不清楚。微量元素和调节金属离子稳态的蛋白质，即金属硫蛋白（MTs）的作用，最近受到了越来越多的关注。本研究的目的是探讨启动子DNA甲基化在MTs转录调控中的作用以及血清微量元素在HCC中的可能预后意义。
招募49例HCC患者并进行临床特征分析。采用电感耦合等离子体质谱法测定血清中的铜、硒和锌含量，对27例患者的HCC组织和同源非肿瘤性肝（N）组织进行检测。通过实时逆转录聚合酶链反应评估肝组织中MT-1和MT-2基因的表达，并通过亚硫酸氢盐扩增子测序评估特定启动子DNA甲基化情况。
血清铜浓度高于第80百分位数的患者生存率显著降低（P < 0.001），死亡风险比显著增加（HR 6.88，95% CI 2.60 - 18.23，P < 0.001）。与N组织相比，HCC组织中的硒和锌水平显著降低（P < 0.0001）。与N组织相比，HCC组织中MT-1和MT-2基因表达显著下调（P < 0.05）。在19例MTs表达下调的HCC组织中，有9例MTs启动子发生高甲基化，在分析的23例患者中，三个特定CpG的甲基化水平与死亡率增加平行（P = 0.015）。
MT-1和MT-2作为潜在的肿瘤抑制基因，通过启动子DNA甲基化进行调控，并且与血清铜浓度一起，与HCC的生存率相关。
