The NF-κB transcription factors are activated via diverse molecular mechanisms in response to various types of stimuli. A plethora of functions associated with specific sets of target genes could be regulated differentially by this factor, affecting cellular response to stress including an anticancer treatment. Here we aimed to compare subsets of NF-κB-dependent genes induced in cells stimulated with a pro-inflammatory cytokine and in cells damaged by a high dose of ionizing radiation (4 and 10 Gy). The RelA-containing NF-κB species were activated by the canonical TNFα-induced and the atypical radiation-induced pathways in human osteosarcoma cells. NF-κB-dependent genes were identified using the gene expression profiling (by RNA-Seq) in cells with downregulated RELA combined with the global profiling of RelA binding sites (by ChIP-Seq), with subsequent validation of selected candidates by quantitative PCR. There were 37 NF-κB-dependent protein-coding genes identified: in all cases RelA bound in their regulatory regions upon activation while downregulation of RELA suppressed their stimulus-induced upregulation, which apparently indicated the positive regulation mode. This set of genes included a few “novel” NF-κB-dependent species. Moreover, the evidence for possible negative regulation of ATF3 gene by NF-κB was collected. The kinetics of the NF-κB activation was slower in cells exposed to radiation than in cytokine-stimulated ones. However, subsets of NF-κB-dependent genes upregulated by both types of stimuli were essentially the same. Hence, one should expect that similar cellular processes resulting from activation of the NF-κB pathway could be induced in cells responding to pro-inflammatory cytokines and in cells where so-called “sterile inflammation” response was initiated by radiation-induced damage.

NF-κB 转录因子通过不同的分子机制响应各种类型的刺激而被激活。与特定靶基因组相关的大量功能可以通过该因子进行差异调节，从而影响细胞对压力的反应，包括抗癌治疗。在这里，我们的目的是比较促炎细胞因子刺激的细胞和高剂量电离辐射（4 和 10 Gy）损伤的细胞中诱导的 NF-κB 依赖性基因子集。人骨肉瘤细胞中含有 RelA 的 NF-κB 物质被经典 TNFα 诱导和非典型辐射诱导途径激活。使用RELA下调的细胞中的基因表达谱（通过 RNA-Seq）结合 RelA 结合位点的全局谱（通过 ChIP-Seq）鉴定 NF-κB 依赖性基因，随后通过定量 PCR 验证选定的候选基因。鉴定出 37 个 NF-κB 依赖性蛋白编码基因：在所有情况下，RelA 在激活后都结合在其调节区域，而RELA的下调抑制了刺激诱导的上调，这显然表明了正调节模式。这组基因包括一些“新的”NF-κB 依赖性物种。此外，还收集了 NF-κB 可能对ATF3基因进行负调控的证据。暴露于辐射的细胞中 NF-κB 激活的动力学比细胞因子刺激的细胞更慢。然而，两种刺激上调的 NF-κB 依赖性基因子集本质上是相同的。 因此，人们应该预期，在对促炎细胞因子做出反应的细胞中，以及在由辐射引起的损伤引发所谓的“无菌炎症”反应的细胞中，可以诱导由 NF-κB 通路激活引起的类似细胞过程。