原发性肺癌患者结核分枝杆菌感染调查及Notch信号通路表达分析

An investigation of Mycobacterium tuberculosis infection and expression of the Notch signaling pathway in patients with primary lung cancer

目的:探究原发性肺癌患者结核分枝杆菌(Mycobacterium tuberculosis,MTB)感染调查及Notch信号通路表达情况。方法:选取2022年1月至2022年6月在重庆大学附属肿瘤医院接受根治术治疗的96例原发性肺癌患者为研究对象,采用原位分子杂交技术和抗酸染色法对肺组织的MTB及其L型进行检测,药敏试验分析其耐药性,测序鉴定靶基因位点突变情况,蛋白印迹法检测肺组织Notch1、Notch2和Notch3蛋白表达。结果:96例原发性肺癌组织标本MTB-L型阳性率为38.54%(37/96),阳性患者痰标本共分离出MTB-L菌株68株;分离MTB-L型菌株对一线抗结核药物耐药率为60.29%(41/68),其中对异烟肼、链霉素、利福平及乙胺丁醇联合使用耐药率最高(22.06%);分离MTB-L型菌株对二线抗结核药物耐药率为36.76%(25/68),其中对氧氟沙星单一用药耐药率最高(14.70%);MTB-L型菌株药物靶基因突变率前3位分别为异烟肼靶基因katG S315T(45.58%)、链霉素靶基因rpsL K43R(42.65%)、利福平靶基因rpoB S450L(20.59%);MTB-L型感染阳性患者肺组织中Notch1、Notch2、Notch3蛋白相对表达量高于MTB-L型阴性者(P<0.05)。结论:原发性肺癌患者MTB感染类型主要为L型,其耐药形势严峻,合并MTB-L型感染患者存在Notch信号通路的异常激活。

Objective:To explore Mycobacterium tuberculosis(MTB)infection and the expression of the Notch signaling pathway in pa⁃tients with primary lung cancer.Methods:A total of 96 patients with primary lung cancer who underwent radical surgery at Chongqing University Cancer Hospital between January 2022 and June 2022 were enrolled as research subjects.MTB and its L-forms in the lung tissue were detected using in situ molecular hybridization and acid-fast staining.Drug resistance was analyzed using a drug susceptibil⁃ity test.Mutations at the sites of target genes were identified using sequencing.The expressions of Notch1,Notch2 and Notch3 proteins in the lung tissue were determined using Western blot.Results:Of the 96 patients with primary lung cancer,the positive rate of MTB-L forms was 38.54%(37/96),with 68 MTB-L strains isolated from the sputum samples of the positive patients.The resistance rate of the isolated MTB-L strains to first-line anti-tuberculosis drugs was 60.29%(41/68),with the highest drug resistance rate of 22.06%for the combination of isoniazid,streptomycin,rifampicin,and ethambutol.The resistance rate of the isolated MTB-L strains to secondline anti-tuberculosis drugs was 36.76%(25/68),with the highest drug resistance rate of 14.70%for ofloxacin alone.The target genes with the top three mutation rates at the drug sites of the MTB-L strains were isoniazid katG S315T(45.58%),streptomycin rpsL K43R(42.65%),and rifampicin rpoB S450L(20.59%).The relative expression levels of Notch1,Notch2,and Notch3 proteins in the lung tissue of patients with positive MTB-L infections were higher than those in the lung tissue of patients with negative MTB-L infections(P<0.05).Conclusion:MTB infection in patients with primary lung cancer is mainly caused by MTB L-forms,and drug resistance is severe.Abnormal activation of the Notch signaling pathway is ob⁃served in patients with MTB-L infection.