[摘 要] 目的：探究甘氨胆酸（GCA）对肺腺癌A549细胞移植瘤小鼠放射治疗敏感性的影响及其机制。方法：建立A549人肺腺癌细胞裸鼠移植瘤模型，随机分为移植瘤对照组（对照组）、GCA组、放疗组（RT组）和GCA + 放疗组（GCA + RT组）。RT组和GCA + RT组接受单次10  Gy照射，GCA组及GCA + RT组连续7 d每日灌胃GCA 280  mg/kg。间隔2 d测量1次移植瘤体积，末次给药后处死小鼠并取移植瘤组织，检测移植瘤组织中超氧化物歧化酶（SOD）与谷胱甘肽过氧化物酶（GSH-Px）活性，qPCR法和WB法分别检测放疗关键基因（MCM6、ITGA6、CASP3等）mRNA和蛋白表达水平，H-E染色观察移植瘤组织的形态变化。通过GEO（GSE276500、GSE294906、GSE218171）及TCGA数据库数据验证放疗关键基因。结果：GCA单用对瘤体生长有一定抑制作用，但联合放疗的GCA + RT组相比单纯放疗组表现出放疗抵抗的效应（P < 0.05）。GCA处理显著提高移植瘤组织SOD活性（P < 0.01）、降低GSH-Px活性（P < 0.01），提示GCA可改变移植瘤抗氧化酶平衡，减弱放疗诱导的氧化应激。GCA干预上调移植瘤组织中MCM6与ITGA6 mRNA表达、下调CASP3 mRNA表达（均P < 0.05）。GCA + RT组移植瘤组织中的MCM6蛋白表达显著高于对照组（P < 0.05）。H-E染色显示，GCA组部分瘤组织坏死，而GCA + RT组坏死组织面积较RT组有所缩小。GEO和TCGA数据库验证支持MCM6、ITGA6高表达与放疗抵抗和预后不良相关。结论：GCA通过增强SOD活性、降低GSH-Px活性并上调ITGA6、MCM6的表达改变氧化应激与关键信号网络，从而削弱A549移植瘤对放疗的敏感性。

Objective To study the application of regional localization method in the thoracoscopic resection of small pulmonary nodule.Methods Sixty-eight cases of small pulmonary nodules were located by applying the small pulmonary nodules regional localization method,and the clinical effect was intraoperatively observed.The ROC curve was used to find the best node for the nodule maximum diameter and minimum distance from the pleural.Results The once successful localization was obtained in 65 cases with the success rate of 95.6％.The best node of the maximum diameter of small pulmonary nodules was 1.0 cm,and the shortest distance from the pleura was 1.3 cm.Conclusion The regional localization method in the thoracoscopic resection of small pulmonary nodule has high accuracy.

Objective To investigate the expression of long chain non-coding(lnc) RNA LOC285194 in breast cancer tissue and paracancerous tissue and its clinical significance.Methods Forty-two samples of paraffin embedded breast cancer tissue and 16 samples of paraffin embedded paracancerous tissue were selected.The expression of lncRNA LOC285194 in these tissue were detected by using quantitative real-time polymerase chain reaction(PCR).Then its correlation with clinicopathological features was analyzed.Results The expression level of lncRNA LOC285194 in breast cancer tissue was significantly lower that in the paracancerous tissue (P＜0.01);the level of lncRNA LOC285194 in human epidermal growth factor receptor-2(HER2)overexpression tissues was up-regulated compared with HER2 negative breast cancer tissue(P =0.013),there was a positive correlation between them(r=0.385,P=0.012).Conclusion lncRNA LOC285194 may play the role of cancer suppressor gene and may be involved in the generation of breast cancer by HER2 association,which may become a target gene of breast cancer treatment.