National Atomic Energy Commission (CNEA), Bariloche Nuclear Medicine and Radiotherapy Integral Center - Institute of Nuclear Technologies for Health Foundation (INTECNUS); Laboratory of Radiobiology and Biodosimetry, S.C. de Bariloche, Argentina.
National Scientific and Technical Research Council (CONICET), Scientific Technical Center CONICET - North Patagonia, Patagonian Andean Institute of Biological and Geo-Environmental Technologies (IPATEC), S.C. de Bariloche, Argentina.
Radiother Oncol. 2021 Jan;154:21-28. doi: 10.1016/j.radonc.2020.09.010. Epub 2020 Sep 12.
The high-throughput analysis of gene expression in ionizing radiation (IR)-exposed human peripheral white blood cells (WBC) has emerged as a novel method for biodosimetry markers detection. We aimed to detect IR-exposure differential expressed genes (DEGs) as potential predictive biomarkers for biodosimetry and radioinduced-response.
We performed a meta-analysis of raw data from public microarrays of ex vivo low linear energy transfer-irradiated human peripheral WBC. Functional enrichment and transcription factors (TF) detection from resulting DEGs were assessed. Six selected DEGs among studies were validated by qRT-PCR on mRNA from human peripheral blood samples from nine healthy human donors 24 h after ex vivo X-rays-irradiation.
We identified 275 DEGs after IR-exposure (parameters: |lfc| ≥ 0.7, q value <0.05), enriched in processes such as regulation after IR-exposure, DNA damage checkpoint, signal transduction by p53 and mitotic cell cycle checkpoint. Among these DEGs, DRAM1, NUDT15, PCNA, PLK2 and TIGAR were selected for qRT-PCR validation. Their expression levels significantly increased at 1-4 Gy respect to non-irradiated controls. Particularly, PCNA increased dose dependently. Curiously, TCF4 (Entrez Gene: 6925), detected as overrepresented TF in the radioinduced DEGs set, significantly decreased post-irradiation.
These six DEGs show potential to be proposed as candidates for IR-exposure biomarkers, considering their observed molecular radioinduced-response. Among them, TCF4, bioinformatically detected, was validated herein as an IR-responsive gene.
利用高通量分析技术对电离辐射（IR）暴露的人外周血白细胞（WBC）中的基因表达进行分析，已成为生物剂量学标志物检测的新方法。我们旨在检测IR 暴露差异表达基因（DEGs），作为生物剂量学和放射性反应的潜在预测生物标志物。
我们对来自体外低线性能量转移 IR 暴露的人外周 WBC 的公共微阵列原始数据进行了荟萃分析。从得到的 DEGs 中评估功能富集和转录因子（TF）检测。在体外 X 射线照射后 24 小时，从 9 名健康人类供体的人外周血样本中提取 mRNA，对 6 项研究中选定的 DEGs 进行 qRT-PCR 验证。
我们在 IR 暴露后鉴定出 275 个 DEGs（参数：| lfc |≥0.7，q 值<0.05），富集于 IR 暴露后的调节、DNA 损伤检查点、p53 信号转导和有丝分裂细胞周期检查点等过程。在这些 DEGs 中，选择了 DRAM1、NUDT15、PCNA、PLK2 和 TIGAR 进行 qRT-PCR 验证。与未照射对照相比，它们的表达水平在 1-4Gy 时显著增加。特别是，PCNA 呈剂量依赖性增加。有趣的是，TCF4（Entrez Gene：6925）作为在放射性诱导的 DEGs 中过度表达的 TF 被检测到，在照射后显著降低。
考虑到这些基因观察到的分子放射性反应，这六个 DEGs 显示出作为 IR 暴露生物标志物候选物的潜力。其中，TCF4 是通过生物信息学检测到的，本文验证了其作为 IR 响应基因的作用。
