Comparison of radiation-induced rat mammary carcinomas from individuals with different sensitivity to diet-induced obesity

Understanding the relationship between radiation-induced breast cancer and obesity, together with information on underlying mechanisms, are potentially useful in risk management and prevention of second cancer in patients receiving radiotherapy. The present study aims to develop a novel animal model to study the relationship by combining two Sprague-Dawley rat models of radiation carcinogenesis and diet-induced obesity. Mammary carcinomas were induced in female obese and lean rats by irradiation with 4 Gy of gamma rays. Gene expression of mammary carcinomas and normal mammary tissues were analyzed with Agilent Whole Rat Genome DNA microarray. The result indicated that genes related to translation and oxidative phosphorylation were upregulated in carcinomas of obese rats.解析辐射诱导乳腺癌与肥胖的关联及其潜在分子机制，有望为接受放疗的患者的风险管控与继发肿瘤预防提供重要理论依据。本研究旨在构建全新动物模型，通过结合辐射致癌与饮食诱导肥胖两种斯普拉格-道利（Sprague-Dawley）大鼠模型，探究上述关联。本研究通过4戈瑞（Gy）γ射线照射，在雌性肥胖大鼠与正常体重对照大鼠体内诱导乳腺腺癌；采用安捷伦（Agilent）全大鼠基因组DNA微阵列芯片，对乳腺腺癌及正常乳腺组织的基因表达水平进行分析。结果显示，肥胖大鼠的乳腺腺癌中，与蛋白质翻译及氧化磷酸化相关的基因呈上调表达。