Microarray analysis of hub genes, non-coding RNAs and pathways in lung after whole body irradiation in a mouse model

Previous research has highlighted the impact of radiation damage, with cancer patients developing acute disorders including radiation induced pneumonitis or chronic disorders including pulmonary fibrosis months after radiation therapy ends. We sought to discover biomarkers that predict these injuries and develop treatments that mitigate this damage and improve quality of life. Six- to eight-week-old female C57BL/6 mice received 1, 2, 4, 8, 12 Gy or sham whole body irradiation. Animals were euthanized 48 h post exposure and lungs removed, snap frozen and underwent RNA isolation. Microarray analysis was performed to determine dysregulation of messenger RNA (mRNA), microRNA (miRNA), and long non-coding RNA (lncRNA) after radiation injury. We observed sustained dysregulation of specific RNA markers including: mRNAs, lncRNAs, and miRNAs across all doses. We also identified significantly upregulated genes that can indicate high dose exposure, including Cpt1c, Pdk4, Gdf15, and Eda2r, which are markers of senescence and fibrosis. Only three miRNAs were significantly dysregulated across all radiation doses: miRNA-142-3p and miRNA-142-5p were downregulated and miRNA-34a-5p was upregulated. IPA analysis predicted inhibition of several molecular pathways with increasing doses of radiation, including: T cell development, Quantity of leukocytes, Quantity of lymphocytes, and Cell viability. These RNA biomarkers might be highly relevant in the development of treatments and in predicting normal tissue injury in patients undergoing radiation treatment. We are conducting further experiments in our laboratory, which includes a human lung-on-a-chip model, to develop a decision tree model using RNA biomarkers.既往研究已证实辐射损伤的危害：癌症患者在放射治疗结束数月后，可能出现包括放射性肺炎在内的急性病症，或包括肺纤维化在内的慢性病症。本研究旨在发掘可预测此类辐射损伤的生物标志物，并开发能够减轻损伤、提升患者生活质量的治疗方案。本实验选用6至8周龄的雌性C57BL/6小鼠，分别给予1、2、4、8、12戈瑞（Gy）的全身照射或假照射处理；于照射后48小时处死小鼠，摘取肺组织并快速冷冻，随后进行核糖核酸（RNA）提取。通过微阵列分析检测辐射损伤后信使核糖核酸（mRNA）、微小核糖核酸（miRNA）及长链非编码核糖核酸（lncRNA）的表达失调情况。结果显示，在所有照射剂量下，特定的RNA标志物（包括mRNA、lncRNA及miRNA）均呈现持续的表达失调。本研究还鉴定出可提示高剂量辐射暴露的显著上调基因，包括Cpt1c、Pdk4、Gdf15及Eda2r，这些基因均为衰老与纤维化的标志物。在所有辐射剂量下，仅有3种miRNA呈现显著表达失调：miRNA-142-3p与miRNA-142-5p表达下调，而miRNA-34a-5p表达上调。IPA分析预测，随着辐射剂量升高，多条分子通路会受到抑制，包括T细胞发育、白细胞数量、淋巴细胞数量及细胞活力相关通路。此类RNA生物标志物或可用于放疗相关治疗方案的开发，以及预测接受放射治疗的患者发生正常组织损伤的风险。本团队目前正在实验室中开展进一步实验，包括构建人类肺芯片模型，以期利用RNA生物标志物开发决策树模型。