放射治疗对乳腺癌患者血浆中microRNAs表达的影响

Radiotherapy induced microRNA expression in the plasma of breast cancer patients

目的 分析乳腺癌放疗患者血浆中miR-210-3p、miR-221-3p、miR-21-5p、miR-150-5p的表达水平的变化,为寻找非均匀辐射致损伤的早期生物标记物提供实验依据。方法 选取乳腺癌患者13例,于放疗前（0 Gy）、放疗2、10、20和30 Gy后的24 h采血。采用实时荧光定量PCR（qRT-PCR）法检测受检者血浆miRNAs的表达水平。结果 不同剂量照射后miR-210-3p、miR-221-3p、miR-21-5p的表达差异无统计学意义（P〉0.05）。miR-150-5p 2 Gy照射后与照射前表达水平差异无统计学意义,但随着照射剂量增加,其表达水平显著下调,分别为照射前的0.808、0.605、0.565（χ2=18.76,P〈0.05）。而在人表皮生长因子受体2（HER2）、雌激素受体（ER）、孕激素受体（PR）的阴性组和阳性组中,miR-150-5p表达差异均无统计学意义（P〉0.05）。结论 电离辐射可诱导miR-150表达显著下调,且存在一定的剂量依赖关系。

Objective To investigate the expressions of miR-210-3p, miR-221-3p, miR-21-5p and miR-150-5p in the plasma of breast cancer patients before and after radiotherapy in order to establish reliable early biomarkers of non-uniform radiation injuries. Methods Blood samples were collected from 13 patients before radiotherapy （0 Gy） and 24 h after radiotherapy of 2, 10, 20, 30 Gy. The miRNAs in the blood plasma were detected with qRT-PCR. Results The levels of miR-210-3p, miR-221-3p, miR-21-5p had no significant difference among different dosage groups after radiotherapy（P〉0.05）. There was no significant difference between the expression of miR-150-5p before and after 2 Gy radiotherapy（P〉0.05）. While the relative level of miR-150-5p gradually decreased to 0.808, 0.605, 0.565 （χ2=18.76, P〈0.05） with increased accumulative dosage of 10, 20, and 30 Gy, respectively. In addition, the miR-150-5p expression levels had no relationship（P〉0.05）with situations （positive or negative group） of human epidermal growth factor receptor 2 （HER2）, estrogen receptor （ER） and progesterone receptor （PR） in the breast cancer cells. Conclusions Ionizing radiation could reduce the expression of miR-150 in the plasma of breast cancer patients in a dose-dependent manner.